development-an-experimental-setup-for-measurement-coefficient

Development of an Experimental Setup for the Measurement of the Coefficient of Restitution under Vacuum Conditions

The Discrete Element Method is used for the simulation of particulate systems to describe and analyze them, to predict and afterwards optimize their ...

Technische Universität Braunschweig

The interaction force between single cells in contact is of high interest in various interdisciplinary fields of biotechnology, for instance, in cultivation or biofilm formation. A method for the determination of adhesion forces between two single Aspergillus niger spores in different aqueous solutions was established in this study. Adhesion force distributions were determined at three different sodium chloride concentrations and two different pH values using an atomic force microscope (AFM). It was pointed out that adhesion data can be described by log-normal density functions, of which corresponding parameters have been estimated. Using the knowledge of distribution shape, the influence of the environmental condition on the mean values of adhesion force could be studied quantitatively. The highest value of 0.95 nN was observed at pH 2.5 and an ionic strength of 0.5 mol L(-1). Decreasing the ionic strength to 0.05 mol L(-1) decreases the adhesion force mean for about 25%. Increasing the pH value to pH 5 at a sodium chloride concentration of 0.154 mol L(-1) entails a decrease of adhesion from 0.88 to 0.56 nN. These results qualitatively agree with the absolute value of the expected surface potential of Aspergillus niger spores, which is much higher at pH 5 and should take more effect at lower concentrations of counterions.

Determination of adhesion between single Aspergillus niger spores in aqueous solutions using an atomic force microscope.

In the past years atomic force microscopy (AFM) techniques have turned out to be a suitable and versatile tool for probing the physical properties of microbial cell surfaces. Besides interaction forces, nanomechanical properties can be obtained from force spectroscopic measurements. Analyzing the recorded force curves by applying appropriate models allows the extraction of cell mechanical parameters, e.g. the Young's modulus or the cellular spring constant. In the present work the nanomechanical properties of the baker's yeast Saccharomyces cerevisiae are extensively studied by force spectroscopy using an AFM. Single cells deform purely elastically so that a cellular spring constant can reliably be determined. It is presented, how this spring constant depends on the probing position on the cell, and how it depends on the extracellular osmotic conditions. Investigations aiming a statistically firm description of the nanomechanical behavior of the yeast cell population are conducted. Finally, the informative value of the cellular spring constant as a cell mechanical parameter is critically discussed.

Atomic force microscopy studies on the nanomechanical properties of Saccharomyces cerevisiae.

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In various biotechnological processes, filamentous fungi, e.g. Aspergillus niger, are widely applied for the production of high value-added products due to their secretion efficiency. There is, however, a tangled relationship between the morphology of these microorganisms, the transport phenomena and the related productivity. The morphological characteristics vary between freely dispersed mycelia and distinct pellets of aggregated biomass. Hence, advantages and disadvantages for mycel or pellet cultivation have to be balanced out carefully. Due to this inadequate understanding of morphogenesis of filamentous microorganisms, fungal morphology, along with reproducibility of inocula of the same quality, is often a bottleneck of productivity in industrial production. To obtain an optimisation of the production process it is of great importance to gain a better understanding of the molecular and cell biology of these microorganisms as well as the approaches in biochemical engineering and particle technique, in particular to characterise the interactions between the growth conditions, cell morphology, spore-hyphae-interactions and product formation. Advances in particle and image analysis techniques as well as micromechanical devices and their applications to fungal cultivations have made available quantitative morphological data on filamentous cells. This chapter provides the ambitious aspects of this line of action, focussing on the control and characterisation of the morphology, the transport gradients and the approaches to understand the metabolism of filamentous fungi. Based on these data, bottlenecks in the morphogenesis of A. niger within the complex production pathways from gene to product should be identified and this may improve the production yield.

Morphology of Filamentous Fungi: Linking Cellular Biology to Process Engineering Using Aspergillus niger.

Dans divers proc&eacute;d&eacute;s biotechnologiques, champignons filamenteux, p. ex. Aspergillus niger, sont largement utilis&eacute;s pour la production de produits &agrave; forte valeur ajout&eacute;es en raison de l&#39;efficacit&eacute; de leur s&eacute;cr&eacute;tion. Il y a, cependant, une relation enchev&ecirc;tr&eacute;e entre la morphologie de ces micro-organismes, les ph&eacute;nom&egrave;nes de transport et de la productivit&eacute; connexe. Les caract&eacute;ristiques morphologiques varient entre myc&eacute;liums librement dispers&eacute;es et distinctes granules de biomasse agr&eacute;g&eacute;e. Donc, avantages et inconv&eacute;nients pour la culture de Lyne ou granul&eacute;s doivent &ecirc;tre compens&eacute;s avec soin. En raison de cette compr&eacute;hension inad&eacute;quate de la morphog&eacute;n&egrave;se des microorganismes filamenteuses, morphologie fongique, ainsi que de la reproductibilit&eacute; des inoculums de m&ecirc;me qualit&eacute;, est souvent un goulot d&#39;&eacute;tranglement de la productivit&eacute; dans la production industrielle. Pour obtenir une optimisation de la production processus il est tr&egrave;s important pour acqu&eacute;rir une meilleure compr&eacute;hension de la biologie mol&eacute;culaire et cellulaire de ces micro-organismes ainsi que les approches en g&eacute;nie biochimique et technique de particules, en particulier pour caract&eacute;riser les interactions entre les conditions de croissance, cellule formation morphologie, spore-hyphes-interactions et produit. Les progr&egrave;s dans les techniques d&#39;analyse de particules et de l&#39;image ainsi que des dispositifs microm&eacute;caniques et leurs applications aux cultures fongiques ont fait des donn&eacute;es morphologiques quantitatifs disponibles sur cellules filamenteuses. Ce chapitre pr&eacute;sente les aspects ambitieuses de cette ligne d&#39;action, en mettant l&#39;accent sur le contr&ocirc;le et la caract&eacute;risation de la morphologie, les gradients de transport et les approches pour comprendre le m&eacute;tabolisme des champignons filamenteux. Selon ces donn&eacute;es, goulots d&#39;&eacute;tranglement dans la morphogen&egrave;se d&#39;a. niger dans les fili&egrave;res de production complexes du g&egrave;ne produit doivent &ecirc;tre identifi&eacute;s et cela peut am&eacute;liorer le rendement de production.

Morphologie des champignons filamenteux : reliant biologie cellulaire au processus technique &agrave; l&#39;aide de Aspergillus niger.

In verschiedenen biotechnologischen Prozessen werden filament&ouml;se Pilze, z. B. Aspergillus Niger, weithin f&uuml;r die Produktion von hohen Mehrwert-Produkte aufgrund ihrer Effizienz Sekretion angewendet. Es gibt jedoch eine verworrene Beziehung zwischen der Morphologie dieser Mikroorganismen, die TRANSPORTPH&Auml;NOMENE und die damit verbundenen Produktivit&auml;t. Die morphologischen Merkmale schwanken zwischen frei verteilten Mycel und verschiedene Pellets von aggregierten Biomasse. Daher m&uuml;ssen vor- und Nachteile f&uuml;r Mycel oder Pellet-Anbau sorgf&auml;ltig ausgeglichen werden. Aufgrund dieser unzureichenden Verst&auml;ndnis der Morphogenese von filament&ouml;sen Mikroorganismen ist pilzartige Morphologie, zusammen mit der Reproduzierbarkeit der Inokula von gleicher Qualit&auml;t, oft ein Engpass der Produktivit&auml;t in der industriellen Produktion. Eine Optimierung der Produktion erhalten Prozess ist es von gro&szlig;er Bedeutung zu gewinnen, ein besseres Verst&auml;ndnis der molekularer und Zelle Biologie dieser Mikroorganismen sowie die Ans&auml;tze in biochemische Technik und Partikel-Technik, insbesondere die Interaktionen zwischen den Wachstumsbedingungen zu pr&auml;gen Zelle Morphologie, Spore-Hyphen-Interaktionen und Produkt-Bildung. Fortschritte in der Partikel und Image-Analyse-Techniken sowie mikromechanischen Ger&auml;ten und ihre Anwendungen auf pilzartigen Kulturen haben morphologische quantitative Daten zur faserigen Zellen gemacht. Dieses Kapitel enth&auml;lt die ambitionierte Aspekte dieser Linie der Ma&szlig;nahme, die Fokussierung auf die Kontrolle und die Charakterisierung der Morphologie, die Transport-Farbverl&auml;ufe und die Ans&auml;tze, den Stoffwechsel von filament&ouml;sen Pilzen zu verstehen. Basierend auf diesen Daten, Engp&auml;sse in der Morphogenese von A. Niger innerhalb der komplexen Herstellungswege vom Gen zum Produkt sollten identifiziert werden und damit kann die Produktionsausbeute erh&ouml;ht.

Morphologie der filament&ouml;se Pilze: Zellbiologie mit Process Engineering mithilfe von Aspergillus Niger zu verkn&uuml;pfen.

In vari processi biotecnologici, funghi filamentosi, p.e. Aspergillus niger, sono ampiamente applicate per la produzione di prodotti ad alto valore aggiunto a causa della loro efficienza di secrezione. Vi &egrave;, tuttavia, un&#39;intricata relazione tra la morfologia di questi microrganismi, i fenomeni di trasporto e la produttivit&agrave; correlata. Le caratteristiche morfologiche variano tra micelio liberamente dispersi e distinti pellet di biomassa aggregato. Quindi, i vantaggi e gli svantaggi per la coltivazione di mycel o pellet devono essere bilanciato con attenzione fuori. A causa di questa comprensione inadeguata della morfogenesi dei microrganismi filamentosi, morfologia fungina, insieme con riproducibilit&agrave; di inoculi della stessa qualit&agrave;, &egrave; spesso un collo di bottiglia della produttivit&agrave; nella produzione industriale. Per ottenere un&#39;ottimizzazione della produzione processo &egrave; di grande importanza per ottenere una migliore comprensione della biologia molecolare e cellulare di questi microrganismi, nonch&eacute; gli approcci in ingegneria biochimica e tecnica delle particelle, in particolare a caratterizzare le interazioni tra le condizioni di crescita, cellule morfologia, spora-IFE-interazioni e prodotto la formazione. Progressi nelle tecniche di analisi della particella e l&#39;immagine cos&igrave; come dispositivi micromeccanici e loro applicazioni alle colture fungine hanno reso disponibili dati morfologici quantitativi sulle cellule filamentose. Questo capitolo fornisce gli aspetti ambiziosi di questa linea di azione, incentrato sul controllo e caratterizzazione della morfologia, i gradienti di trasporto e gli approcci per comprendere il metabolismo di funghi filamentosi. Sulla base di questi dati, i colli di bottiglia nella morfogenesi a. niger entro i percorsi di produzione complessi da gene al prodotto devono essere identificate e questo pu&ograve; migliorare il rendimento di produzione.

Morfologia dei funghi filamentosi: collegamento biologia cellulare processo ingegneria utilizzando Aspergillus niger.

&#x69D8;&#x3005; &#x306A;&#x30D0;&#x30A4;&#x30AA; &#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x3001;&#x7CF8;&#x72B6;&#x83CC;&#x3001;&#x4F8B;&#x3048;&#x3070;&#x30B3;&#x30A6;&#x30B8;&#x30AB;&#x30D3; &#x30CB;&#x30B8;&#x30A7;&#x30FC;&#x30EB;&#x3001;&#x5E83;&#x304F;&#x305D;&#x306E;&#x5206;&#x6CCC;&#x52B9;&#x7387;&#x306B;&#x3088;&#x308B;&#x9AD8;&#x4ED8;&#x52A0;&#x4FA1;&#x5024;&#x88FD;&#x54C1;&#x306E;&#x751F;&#x7523;&#x306E;&#x305F;&#x3081;&#x306B;&#x9069;&#x7528;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x3057;&#x304B;&#x3057;&#x3001;&#x3053;&#x308C;&#x3089;&#x306E;&#x5FAE;&#x751F;&#x7269;&#x3001;&#x8F38;&#x9001;&#x73FE;&#x8C61;&#x3068;&#x95A2;&#x9023;&#x3059;&#x308B;&#x751F;&#x7523;&#x6027;&#x306E;&#x5F62;&#x614B;&#x306E;&#x3082;&#x3064;&#x308C;&#x305F;&#x95A2;&#x4FC2;&#x3067;&#x3059;&#x3002;&#x5F62;&#x614B;&#x306E;&#x7279;&#x5FB4;&#x306F;&#x3001;&#x81EA;&#x7531;&#x306B;&#x5206;&#x6563;&#x3057;&#x305F;&#x83CC;&#x7CF8;&#x4F53;&#x3068;&#x660E;&#x77AD;&#x306A;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x96C6;&#x8A08;&#x30D0;&#x30A4;&#x30AA;&#x30DE;&#x30B9;&#x306E;&#x9593;&#x7570;&#x306A;&#x308A;&#x307E;&#x3059;&#x3002;&#x3057;&#x305F;&#x304C;&#x3063;&#x3066;&#x3001;mycel &#x307E;&#x305F;&#x306F;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x683D;&#x57F9;&#x306E;&#x9577;&#x6240;&#x3068;&#x77ED;&#x6240;&#x3092;&#x614E;&#x91CD;&#x306B;&#x30D0;&#x30E9;&#x30F3;&#x30B9;&#x3092;&#x3068;&#x3089;&#x308C;&#x308B;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x3053;&#x306E;&#x7CF8;&#x72B6;&#x5FAE;&#x751F;&#x7269;&#x306E;&#x5F62;&#x614B;&#x5F62;&#x6210;&#x306E;&#x4E0D;&#x5341;&#x5206;&#x306A;&#x7406;&#x89E3;&#x306B;&#x3088;&#x308A;&#x3001;&#x540C;&#x3058;&#x54C1;&#x8CEA;&#x306E;&#x63A5;&#x7A2E;&#x306E;&#x518D;&#x73FE;&#x6027;&#x3068;&#x3068;&#x3082;&#x306B;&#x3001;&#x771F;&#x83CC;&#x306E;&#x5F62;&#x614B;&#x306F;&#x3001;&#x3057;&#x3070;&#x3057;&#x3070;&#x5DE5;&#x696D;&#x751F;&#x7523;&#x306B;&#x304A;&#x3051;&#x308B;&#x751F;&#x7523;&#x6027;&#x306E;&#x30DC;&#x30C8;&#x30EB;&#x30CD;&#x30C3;&#x30AF;&#x3067;&#x3059;&#x3002;&#x751F;&#x7523;&#x306E;&#x6700;&#x9069;&#x5316;&#x3092;&#x53D6;&#x5F97;&#x3059;&#x308B;&#x306B;&#x306F;&#x3001;&#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x306E;&#x751F;&#x7269;&#x5316;&#x5B66;&#x5DE5;&#x5B66;&#x304A;&#x3088;&#x3073;&#x30D1;&#x30FC;&#x30C6;&#x30A3;&#x30AF;&#x30EB;&#x624B;&#x6CD5;&#x3067;&#x30A2;&#x30D7;&#x30ED;&#x30FC;&#x30C1;&#x3068;&#x540C;&#x69D8;&#x306B;&#x3053;&#x308C;&#x3089;&#x306E;&#x5FAE;&#x751F;&#x7269;&#x306E;&#x5206;&#x5B50;&#x304A;&#x3088;&#x3073;&#x7D30;&#x80DE;&#x751F;&#x7269;&#x5B66;&#x306E;&#x7406;&#x89E3;&#x3092;&#x5F97;&#x308B;&#x305F;&#x3081;&#x306B;&#x975E;&#x5E38;&#x306B;&#x91CD;&#x8981;&#x3067;&#x3059;&#x7279;&#x306B;&#x6210;&#x9577;&#x6761;&#x4EF6;&#x9593;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x3092;&#x7279;&#x5FB4;&#x4ED8;&#x3051;&#x308B;&#x305F;&#x3081;&#x7D30;&#x80DE;&#x5F62;&#x614B;, &#x80DE;&#x5B50;&#x83CC;&#x7CF8;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x304A;&#x3088;&#x3073;&#x88FD;&#x54C1;&#x5F62;&#x6210;&#x3002;&#x30DE;&#x30A4;&#x30AF;&#x30ED;&#x30E1;&#x30AB;&#x30CB;&#x30AB;&#x30EB; &#x30C7;&#x30D0;&#x30A4;&#x30B9;&#x3068;&#x540C;&#x69D8;&#x306B;&#x7C92;&#x5B50;&#x3068;&#x753B;&#x50CF;&#x89E3;&#x6790;&#x6280;&#x8853;&#x306E;&#x9032;&#x6B69;&#x304A;&#x3088;&#x3073;&#x771F;&#x83CC;&#x57F9;&#x990A;&#x3078;&#x306E;&#x5FDC;&#x7528;&#x5229;&#x7528;&#x306E;&#x5B9A;&#x91CF;&#x7684;&#x5F62;&#x614B;&#x30C7;&#x30FC;&#x30BF;&#x7CF8;&#x72B6;&#x7D30;&#x80DE;&#x3092;&#x4F5C;&#x3063;&#x305F;&#x3002;&#x5236;&#x5FA1;&#x3068;&#x30AD;&#x30E3;&#x30E9;&#x30AF;&#x30BF;&#x30EA;&#x30BC;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x306E;&#x5F62;&#x614B;&#x3068;&#x30C8;&#x30E9;&#x30F3;&#x30B9;&#x30DD;&#x30FC;&#x30C8; &#x30B0;&#x30E9;&#x30C7;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x3068;&#x7CF8;&#x72B6;&#x83CC;&#x306E;&#x4EE3;&#x8B1D;&#x3092;&#x7406;&#x89E3;&#x3059;&#x308B;&#x30A2;&#x30D7;&#x30ED;&#x30FC;&#x30C1;&#x306B;&#x7126;&#x70B9;&#x3092;&#x5F53;&#x3066;&#x3001;&#x884C;&#x52D5;&#x306E;&#x3053;&#x306E;&#x30E9;&#x30A4;&#x30F3;&#x306E;&#x91CE;&#x5FC3;&#x7684;&#x306A;&#x5074;&#x9762;&#x306B;&#x3064;&#x3044;&#x3066;&#x8AAC;&#x660E;&#x3057;&#x307E;&#x3059;&#x3002;&#x3053;&#x308C;&#x3089;&#x306E;&#x30C7;&#x30FC;&#x30BF;&#x306B;&#x57FA;&#x3065;&#x3044;&#x3066;&#x3001;A. &#x30CB;&#x30B8;&#x30A7;&#x30FC;&#x30EB;&#x907A;&#x4F1D;&#x5B50;&#x304B;&#x3089;&#x88FD;&#x54C1;&#x306E;&#x8907;&#x96D1;&#x306A;&#x751F;&#x7523;&#x7D4C;&#x8DEF;&#x5185;&#x306E;&#x5F62;&#x614B;&#x5F62;&#x6210;&#x306B;&#x304A;&#x3051;&#x308B;&#x30DC;&#x30C8;&#x30EB;&#x30CD;&#x30C3;&#x30AF;&#x3092;&#x7279;&#x5B9A;&#x3059;&#x308B;&#x5FC5;&#x8981;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3001;&#x3053;&#x306E;&#x751F;&#x7523;&#x6B69;&#x7559;&#x308A;&#x5411;&#x4E0A;&#x53EF;&#x80FD;&#x6027;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;

&#x7CF8;&#x72B6;&#x83CC;&#x306E;&#x5F62;&#x614B;: &#x7D30;&#x80DE;&#x751F;&#x7269;&#x5B66;&#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x5DE5;&#x5B66;&#x3092;&#x7528;&#x3044;&#x305F;&#x30B3;&#x30A6;&#x30B8;&#x30AB;&#x30D3; &#x30CB;&#x30B8;&#x30A7;&#x30FC;&#x30EB;&#x306B;&#x30EA;&#x30F3;&#x30AF;&#x3057;&#x307E;&#x3059;&#x3002;

&#xB2E4;&#xC591; &#xD55C; &#xBC14;&#xC774;&#xC624; &#xD504;&#xB85C;&#xC138;&#xC2A4;&#xC5D0;&#xC11C; filamentous &#xACF0; &#xD321;&#xC774;, &#xC608;&#xB97C; &#xB4E4;&#xBA74; &#xB204; &#xB2C8;&#xC81C;&#xB974;, &#xADF8;&#xB4E4;&#xC758; &#xBD84; &#xBE44; &#xD6A8;&#xC728;&#xC73C;&#xB85C; &#xC778;&#xD574; &#xACE0;&#xBD80;&#xAC00;&#xAC00;&#xCE58; &#xC81C;&#xD488;&#xC758; &#xC0DD;&#xC0B0;&#xC5D0; &#xB300; &#xD55C; &#xAD11;&#xBC94;&#xC704; &#xD558; &#xAC8C; &#xC801;&#xC6A9; &#xB429;&#xB2C8;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098;, &#xC774;&#xB7EC;&#xD55C; &#xBBF8;&#xC0DD;&#xBB3C;, &#xC804;&#xC1A1; &#xD604;&#xC0C1;&#xACFC; &#xAD00;&#xB828;&#xB41C; &#xC0DD;&#xC0B0;&#xC131;&#xC758; &#xD615;&#xD0DC; &#xC0AC;&#xC774;&#xC758; &#xC5BD;&#xD78C;&#xB41C; &#xAD00;&#xACC4;&#xC785;&#xB2C8;&#xB2E4;. &#xD615;&#xD0DC;&#xD559; &#xD2B9;&#xC131; &#xC790;&#xC720;&#xB86D;&#xAC8C; &#xBD84;&#xC0B0; &#xB41C; &#xC0AC;&#xCCB4; &#xBC0F; &#xC9D1;&#xACC4; &#xB41C; &#xBC14;&#xC774;&#xC624; &#xB9E4;&#xC2A4;&#xC758; &#xB69C;&#xB837;&#xD55C; &#xD3A0; &#xB9BF;&#xC5D0; &#xB530;&#xB77C; &#xB2E4;&#xB985;&#xB2C8;&#xB2E4;. &#xB530;&#xB77C;&#xC11C;, mycel &#xB610;&#xB294; &#xD3A0; &#xB81B; &#xC7AC;&#xBC30;&#xC5D0; &#xB300; &#xD55C; &#xC7A5;&#xB2E8;&#xC810; &#xBC16;&#xC73C;&#xB85C; &#xADE0;&#xD615;&#xC744; &#xC2E0;&#xC911; &#xD558; &#xAC8C; &#xD574;&#xC57C; &#xD569;&#xB2C8;&#xB2E4;. Morphogenesis filamentous &#xBBF8;&#xC0DD;&#xBB3C;&#xC758;&#xC774; &#xBD88; &#xCDA9; &#xBD84; &#xD55C; &#xC774;&#xD574;, &#xB3D9;&#xC77C;&#xD55C; &#xD488;&#xC9C8;&#xC758; inocula&#xC758; &#xC7AC;&#xD604;&#xC131; &#xD568;&#xAED8; &#xACF0; &#xD321;&#xC774; &#xD615;&#xD0DC; &#xC885;&#xC885; &#xC0B0;&#xC5C5; &#xC0DD;&#xC0B0;&#xC5D0;&#xC11C; &#xC0DD;&#xC0B0;&#xC131;&#xC758; &#xBCD1;&#xBAA9;&#xC740;. &#xC0DD;&#xC0B0;&#xC758; &#xCD5C;&#xC801;&#xD654;&#xB97C; &#xACFC;&#xC815; &#xADF8;&#xAC83;&#xC740; &#xC774;&#xB7EC;&#xD55C; &#xBBF8;&#xC0DD;&#xBB3C; &#xC0DD;&#xBB3C; &#xACF5;&#xD559; &#xBC0F; &#xC785;&#xC790; &#xAE30;&#xC220;&#xC5D0; &#xC811;&#xADFC;&#xC758; &#xBD84;&#xC790; &#xBC0F; &#xC138;&#xD3EC; &#xC0DD;&#xBB3C;&#xD559;&#xC758; &#xB354; &#xB098;&#xC740; &#xC774;&#xD574;&#xB97C; &#xC5BB;&#xAE30; &#xC704;&#xD574; &#xB9E4;&#xC6B0; &#xC911;&#xC694; &#xD2B9;&#xD788; characterise &#xC131;&#xC7A5; &#xC870;&#xAC74; &#xAC04;&#xC758; &#xC0C1;&#xD638; &#xC791;&#xC6A9;&#xC744; &#xC138;&#xD3EC; &#xD615;&#xD0DC;, &#xD3EC;&#xC790; &#xADE0; &#xC0C1;&#xD638; &#xC791;&#xC6A9; &#xBC0F; &#xC81C;&#xD488; &#xD615;&#xC131;. &#xC785;&#xC790; &#xBC0F; &#xC774;&#xBBF8;&#xC9C0; &#xBD84;&#xC11D; &#xAE30;&#xBC95;&#xC73C;&#xB85C; micromechanical &#xC7A5;&#xCE58;&#xC5D0; &#xBC1C;&#xC804;&#xACFC; &#xC751;&#xC6A9; &#xD504;&#xB85C;&#xADF8;&#xB7A8;&#xC744; &#xACF0; &#xD321;&#xC774; &#xC9C0;&#xCF1C;&#xC628; filamentous &#xC140;&#xC5D0; &#xC0AC;&#xC6A9;&#xD560; &#xC218; &#xC788;&#xB294; &#xC591;&#xC801; &#xD615;&#xD0DC;&#xD559; &#xB370;&#xC774;&#xD130;&#xB97C; &#xB9CC;&#xB4E4;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xC774; &#xC7A5;&#xC5D0;&#xC11C; &#xB3D9;&#xC791;, &#xCEE8;&#xD2B8;&#xB864; &#xBC0F; &#xD615;&#xD0DC;, &#xC804;&#xC1A1; &#xADF8;&#xB77C;&#xB514;&#xC5B8;&#xD2B8; filamentous &#xACF0; &#xD321;&#xC774;&#xC758; &#xBB3C;&#xC9C8; &#xB300;&#xC0AC;&#xB97C; &#xC774;&#xD574; &#xC811;&#xADFC;&#xBC95;&#xC758; &#xD2B9;&#xC131; &#xBD84;&#xC11D;&#xC5D0; &#xAD6D;&#xD55C;&#xC758;&#xC774; &#xB77C;&#xC778;&#xC758; &#xC57C;&#xC2EC;&#xCC2C; &#xCE21;&#xBA74;. &#xC774;&#xB7EC;&#xD55C; &#xB370;&#xC774;&#xD130;&#xB97C; &#xBC14;&#xD0D5;&#xC73C;&#xB85C;, &#xC720;&#xC804;&#xC790; &#xC81C;&#xD488;&#xC758; &#xBCF5;&#xC7A1; &#xD55C; &#xC0DD;&#xC0B0; &#xACBD;&#xB85C; &#xB0B4;&#xC5D0;&#xC11C; A. &#xB2C8;&#xC81C;&#xB974; morphogenesis&#xC758; &#xBCD1;&#xBAA9; &#xC0C1;&#xD0DC;&#xB97C; &#xC2DD;&#xBCC4; &#xD558; &#xACE0;&#xC774; &#xC0DD;&#xC0B0; &#xC218;&#xC728;&#xC744; &#xD5A5;&#xC0C1; &#xC2DC;&#xD0AC; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

Filamentous &#xACF0; &#xD321;&#xC774;&#xC758; &#xD615;&#xD0DC;: &#xC138;&#xD3EC; &#xC0DD;&#xBB3C;&#xD559; &#xD504;&#xB85C;&#xC138;&#xC2A4; &#xC5D4;&#xC9C0;&#xB2C8;&#xC5B4;&#xB9C1;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xB204; &#xB2C8;&#xC81C;&#xB974;&#xC5D0; &#xC5F0;&#xACB0; &#xD569;&#xB2C8;&#xB2E4;.

En diversos procesos biotecnol&oacute;gicos, hongos filamentosos, por ejemplo Aspergillus N&iacute;ger, se aplican ampliamente para la producci&oacute;n de productos de alto valor a&ntilde;adidos debido a su eficacia de secreci&oacute;n. Sin embargo, hay una relaci&oacute;n enredada entre la morfolog&iacute;a de estos microorganismos, los fen&oacute;menos de transporte y la productividad relacionada. Las caracter&iacute;sticas morfol&oacute;gicas var&iacute;an entre micelio libremente disperso y distintos pellets de biomasa agregada. Por lo tanto, ventajas y desventajas para el cultivo mycel o di&aacute;bolo deben sopesarse cuidadosamente hacia fuera. Debido a esta falta de comprensi&oacute;n de la morfog&eacute;nesis de microorganismos filamentosos, morfolog&iacute;a de hongo, junto con la reproducibilidad de los in&oacute;culos de la misma calidad, es a menudo un cuello de botella de la productividad en la producci&oacute;n industrial. Para obtener una optimizaci&oacute;n de la producci&oacute;n proceso es de gran importancia para lograr una mejor comprensi&oacute;n de la biolog&iacute;a molecular y celular de estos microorganismos, as&iacute; como los enfoques en Ingenier&iacute;a Bioqu&iacute;mica y t&eacute;cnica de la part&iacute;cula, en particular para caracterizar las interacciones entre las condiciones de crecimiento, c&eacute;lula de morfolog&iacute;a, espora-hifas-interacciones y producto de la formaci&oacute;n. Avances en t&eacute;cnicas de an&aacute;lisis de part&iacute;culas y de imagen, as&iacute; como dispositivos de Micromec&aacute;nica y sus aplicaciones a los cultivos de hongos han hecho disponibles datos morfol&oacute;gicos cuantitativos sobre c&eacute;lulas filamentosas. Este cap&iacute;tulo proporciona lo ambicioso de esta l&iacute;nea de acci&oacute;n, centr&aacute;ndose en el control y la caracterizaci&oacute;n de la morfolog&iacute;a, los gradientes de transporte y los enfoques para comprender el metabolismo de hongos filamentosos. Basado en estos datos, se deben identificar los cuellos de botella en la morfog&eacute;nesis de a. niger en las v&iacute;as de producci&oacute;n compleja de gene al producto y esto puede mejorar el rendimiento de la producci&oacute;n.

Morfolog&iacute;a de hongos filamentosos: enlazan a la biolog&iacute;a celular a proceso ingenier&iacute;a con Aspergillus niger.

The electrostatic surface potential of fungal spores is generally regarded as potentially influencing spore aggregation and pellet formation in submerged cultures of filamentous fungi. Spores of Aspergillus niger are typically characterized by negative zeta potentials over a wide range of pH values. In this study, this particular behavior is ascribed to the presence of an extensive melanin coating. It is proposed on the basis of zeta potential and pigment extraction experiments that this outermost layer affects the pH-dependent surface potential in two manners: (i) by the addition of negative charges to the spore surface and (ii) by the pH-dependent release of melanin pigment. Chemical analyses revealed that deprotonation of melanin-bound carboxyl groups is most probably responsible for pigment release under acidic conditions. These findings were incorporated into a simple model which has the ability to qualitatively explain the results of zeta potential experiments and, moreover, to provide the basis for quantitative investigations on the role of electrostatics in spore aggregation.

On the origin of the electrostatic surface potential of Aspergillus niger spores in acidic environments.

&#x771F;&#x83CC;&#x5728;&#x5404;&#x79CD;&#x5404;&#x6837;&#x7684;&#x6709;&#x673A;&#x548C;&#x65E0;&#x673A;&#x6750;&#x6599;&#x4E0A;&#x751F;&#x957F;&#x3002;&#x6B96;&#x6C11;&#x5730;&#x5EFA;&#x7ACB;&#x548C;&#x56FA;&#x4F53;&#x8868;&#x9762;&#x751F;&#x957F;&#x9700;&#x8981;&#x7684;&#x5B62;&#x5B50;&#x548C;&#x83CC;&#x4E1D;&#x5728;&#x57FA;&#x4F53;&#x7684;&#x9644;&#x7740;&#x529B;&#xFF0C;&#x800C;&#x5B62;&#x5B50;&#x6216;&#x83CC;&#x4E1D;&#x7EC6;&#x80DE;-&#x7EC6;&#x80DE;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x662F;&#x4E09;&#x7EF4;&#x7684;&#x83CC;&#x4E1D;&#x7ED3;&#x6784;&#xFF0C;&#x5982;&#x5FAE;&#x4E38;&#x6216;&#x751F;&#x7269;&#x819C;&#x53D1;&#x5C55;&#x7684;&#x5148;&#x51B3;&#x6761;&#x4EF6;&#x3002;&#x8868;&#x9762;&#x9075;&#x5B88;&#x5DF2;&#x88AB;&#x63CF;&#x8FF0;&#x4E3A;&#x4E00;&#x4E2A;&#x4E24;&#x6B65;&#x8FC7;&#x7A0B;&#xFF0C;&#x7EC4;&#x6210;&#x7684;&#x521D;&#x59CB;&#x9644;&#x4EF6;&#x672A;&#x840C;&#x53D1;&#x7684;&#x5206;&#x751F;&#x5B62;&#x5B50;&#x8DDF;&#x8FDB;&#x4E00;&#x6B65;&#x7C98;&#x8FDE;&#x5F62;&#x6210;&#x80DA;&#x7BA1;&#x548C;&#x8D8A;&#x6765;&#x8D8A;&#x591A;&#x7684;&#x83CC;&#x4E1D;&#x3002;&#x5728;&#x672C;&#x7814;&#x7A76;&#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x5206;&#x6790;&#x4E86;&#x672A;&#x840C;&#x53D1;&#x7684;&#x5B62;&#x5B50;&#x9897;&#x7C92;&#x548C;&#x751F;&#x7269;&#x819C;&#x5F62;&#x6210;&#x7684;&#x9ED1;&#x66F2;&#x9709;&#x7C98;&#x9644;&#x7684;&#x8D21;&#x732E;&#x3002;&#x9ED1;&#x8272;&#x7D20;&#x751F;&#x7269;&#x5408;&#x6210;&#x7F3A;&#x9677;&#x7A81;&#x53D8;&#x4F53;&#x5EFA;&#x9020;&#x4E86;&#x5220;&#x9664;&#x7684; alb1 &#x57FA;&#x56E0;&#xFF0C;&#x7F16;&#x7801;&#x805A;&#x916E;&#x5408;&#x9176;&#x7D20;&#x751F;&#x7269;&#x5408;&#x6210;&#x7684;&#x5FC5;&#x8981;&#x6761;&#x4EF6;&#x3002;&Delta;alb1 &#x5206;&#x751F;&#x5B62;&#x5B50;&#x6709;&#x66F4;&#x6539;&#x7684;&#x8868;&#x9762;&#x7ED3;&#x6784;&#x548C;&#x7269;&#x5316;&#x8868;&#x9762;&#x5C5E;&#x6027;&#x66F4;&#x6539;&#x3002;&#x5B62;&#x5B50;&#x805A;&#x96C6;&#x7684;&#x6DB2;&#x4F53;&#x57F9;&#x517B;&#x4EE5;&#x53CA;&#x5B62;&#x5B50;&#x8868;&#x9762;&#x9644;&#x4EF6;&#x91CE;&#x751F;&#x578B;&#x4E0E;&#x7A81;&#x53D8;&#x4F53;&#x4E4B;&#x95F4;&#x4E0D;&#x540C; pH &#x4F9D;&#x8D56;&#x7684;&#x65B9;&#x5F0F;&#x3002;&#x5728;&#x6DB2;&#x4F53;&#x57F9;&#x517B;&#x8FDB;&#x4E00;&#x6B65;&#x9897;&#x7C92;&#x5F62;&#x6210;&#x4E0D;&#x53D7;&#x66F4;&#x6539;&#x7684;&#x5B62;&#x5B50;&#x5B62;&#x5B50;&#x7684;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#xFF0C;&#x6307;&#x793A;&#x82BD;&#x7BA1;&#x548C;&#x83CC;&#x4E1D;&#x9075;&#x5B88;&#x53EF;&#x4EE5;&#x5F25;&#x8865;&#x4E0D;&#x8DB3;&#x4E4B;&#x5904;&#x7684;&#x5B62;&#x5B50;&#x9644;&#x4EF6;&#x7684;&#x7B2C;&#x4E00;&#x6B65;&#x3002;&#x76F8;&#x6BD4;&#x4E4B;&#x4E0B;&#xFF0C;&#x4FC3;&#x8FDB; &Delta;alb1 &#x5206;&#x751F;&#x5B62;&#x5B50;&#x5BF9;&#x805A;&#x5408;&#x7269;&#x8868;&#x9762;&#x7C98;&#x9644;&#x7684;&#x6761;&#x4EF6;&#x4E0B;&#x7684;&#x7A81;&#x53D8;&#x5F62;&#x5F0F;&#x66F4;&#x7A33;&#x5B9A;&#x751F;&#x7269;&#x819C;&#x6BD4;&#x91CE;&#x751F;&#x578B;&#xFF0C;&#x8FD9;&#x8868;&#x660E;&#x521D;&#x59CB;&#x5B62;&#x5B50;&#x7C98;&#x9644;&#x652F;&#x6301;&#x56FA;&#x7740;&#x751F;&#x957F;&#x3002;

&#x521D;&#x59CB;&#x5B62;&#x5B50;&#x7C98;&#x9644;&#x5728;&#x9ED1;&#x66F2;&#x9709;&#x7403;&#x56E2;&#x4E0E;&#x751F;&#x7269;&#x819C;&#x5F62;&#x6210;&#x7684;&#x4F5C;&#x7528;&#x3002;

Fungi grow on a great variety of organic and inorganic materials. Colony establishment and growth on solid surfaces require adhesion of spores and hyphae to the substrate, while cell-to-cell interactions among spores and/or hyphae are a prerequisite for the development of three-dimensional mycelial structures such as pellets or biofilms. Surface adherence has been described as a two-step process, comprised of the initial attachment of ungerminated conidia followed by further adhesion of the forming germ tubes and growing hyphae. In the present study, we analyzed the contribution of adhesion of ungerminated spores to pellet and biofilm formation in Aspergillus niger. Mutants deficient in melanin biosynthesis were constructed by the deletion of the alb1 gene, encoding a polyketide synthase essential for pigment biosynthesis. Î”alb1 conidia have an altered surface structure and changed physicochemical surface properties. Spore aggregation in liquid culture as well as spore surface attachment differ between the wild type and the mutant in a pH-dependent manner. In liquid culture further pellet formation is unaffected by altered spore-spore interactions, indicating that germ tube and hyphal adherence can compensate for deficiencies in the initial step of spore attachment. In contrast, under conditions promoting adhesion of Î”alb1 conidia to polymer surfaces the mutant forms more stable biofilms than the wild type, suggesting that initial spore adhesion supports sessile growth.

The role of initial spore adhesion in pellet and biofilm formation in Aspergillus niger.

Les champignons poussent sur une grande vari&eacute;t&eacute; de mat&eacute;riaux organiques et inorganiques. Cr&eacute;ation de la colonie et de la croissance sur des surfaces solides requi&egrave;rent adh&eacute;sion des spores et des hyphes au substrat, tandis que les interactions cellule-cellule parmi des spores ou des hyphes sont une condition sine qua non pour d&eacute;velopper des structures de myc&eacute;liums en trois dimensions tels que les granul&eacute;s ou les biofilms. Adh&eacute;rence de surface a &eacute;t&eacute; d&eacute;crit comme un processus en deux &eacute;tapes, compos&eacute; de la saisie initiale des conidies non germ&eacute;es suivie d&#39;adh&eacute;rence suppl&eacute;mentaire du formage des tubes germinatifs et des hyphes croissants. Dans la pr&eacute;sente &eacute;tude, nous avons analys&eacute; la contribution de l&#39;adh&eacute;rence des spores germ&eacute;es pour granuler et la formation de biofilm chez Aspergillus niger. Mutants d&eacute;ficients dans la biosynth&egrave;se de la m&eacute;lanine ont &eacute;t&eacute; construits par la d&eacute;l&eacute;tion du g&egrave;ne alb1, codant une synthase de polyketide essentielle pour la biosynth&egrave;se des pigments. Les conidies de &Delta;alb1 ont une structure de surface alt&eacute;r&eacute;e et chang&eacute; les propri&eacute;t&eacute;s physico-chimiques de la surface. Agr&eacute;gation de spore en culture liquide comme attachement surface spore diff&egrave;rent entre le type sauvage et le mutant d&#39;une mani&egrave;re d&eacute;pendante du pH. En granul&eacute;s autre culture liquide formation est affect&eacute;e par les interactions de spore-spore alt&eacute;r&eacute;e, indiquant que tube germinatif et l&#39;adh&eacute;rence des hyphes peuvent compenser les insuffisances dans l&#39;&eacute;tape initiale de l&#39;attachement de la spore. En revanche, dans des conditions favorisant l&#39;adh&eacute;rence des conidies de &Delta;alb1 aux surfaces polym&egrave;res les formes mutantes stable plus biofilms que le type sauvage, ce qui sugg&egrave;re qu&#39;adh&eacute;rence initiale spore prend en charge la croissance sessile.

Le r&ocirc;le de l&#39;adh&eacute;rence initiale de spore &agrave; pellet et biofilm formation chez Aspergillus niger.

Pilze wachsen auf einer Vielzahl von organischen und anorganischen Materialien. Kolonie-Gr&uuml;ndung und das Wachstum auf festen Oberfl&auml;chen erfordern Haftung von Sporen und Hyphen auf das Substrat w&auml;hrend Zell-Zell-Interaktionen zwischen/Sporen oder hyphen Voraussetzung f&uuml;r die Entwicklung von dreidimensionalen mycelial Strukturen wie Pellets oder Biofilme sind. Einhaltung der Oberfl&auml;che wurde als ein zweistufiger Prozess, bestehend aus der urspr&uuml;nglichen Anlage ungerminated Konidien, gefolgt von weiteren Adh&auml;sion der Umformung Keim-Rohre und zunehmenden Hyphen beschrieben. In der vorliegenden Studie analysierten wir den Beitrag der Haftung von ungerminated Sporen f&uuml;r pellet und Biofilm-Bildung in Aspergillus Niger. Durch die Streichung des Gens alb1 Codierung ein Polyketide Synthase f&uuml;r Pigment-Biosynthese Mutanten einen Mangel an Melanin Biosynthese entstanden. &Delta;alb1 Konidien haben eine ver&auml;nderte Oberfl&auml;chenstruktur und physikalisch-chemischen Eigenschaften der Oberfl&auml;che ver&auml;ndert. Spore-Aggregation in fl&uuml;ssiger Kultur sowie Spore Oberfl&auml;che Anlage unterscheiden den Wildtyp und den Mutanten in einer pH-abh&auml;ngigen Weise. In fl&uuml;ssiger Kultur weitere Pellet ist Bildung unabh&auml;ngig von ver&auml;nderten Spore-Spore-Interaktionen, darauf hinweist, dass M&auml;ngel im ersten Schritt der Spore Anlage Keim Rohr und geflochtenen Einhaltung ausgleichen k&ouml;nnen. Die mutierten Formen stabil dagegen unter Bedingungen, die F&ouml;rderung der Adh&auml;sion von &Delta;alb1 Konidien auf Polymer-Oberfl&auml;chen mehr Biofilme als der Wildtyp, was darauf hindeutet, dass anf&auml;ngliche Spore Adh&auml;sion sessile Wachstum unterst&uuml;tzt.

Die Rolle des urspr&uuml;nglichen Spore Adh&auml;sion in Pellet und Biofilm Formation Aspergillus Niger.

Funghi crescono su una grande variet&agrave; di materiali organici e inorganici. Stabilimento di Colonia e di crescita su superfici solide richiedono adesione delle spore e IFE al substrato, mentre interazioni cellula-cellula fra le spore o IFE sono un prerequisito per lo sviluppo di strutture miceliari tridimensionali come pellets o biofilm. Aderenza superficiale &egrave; stato descritto come un processo in due fasi, compreso l&#39;attacco iniziale dei conidi ungerminated seguita da ulteriore adesione della formatura tubi germe e crescente IFE. Nel presente studio, abbiamo analizzato il contributo di adesione delle spore ungerminated a pellet e formazione di biofilm in Aspergillus niger. Mutanti carenti nella biosintesi di melanina furono costruite da delezione del gene alb1, che codifica un synthase di polyketide essenziale per la biosintesi di pigmento. &Delta;alb1 conidi hanno una struttura superficiale alterata e cambiato propriet&agrave; fisico-chimiche della superficie. Aggregazione di spore in coltura liquida cos&igrave; come attaccamento superficiale spora differiscono tra wild type e il mutante in modo pH-dipendente. Nel pellet ulteriore liquido cultura formazione &egrave; influenzato da interazioni alterata di spore spore, indicando che germe tubo e aderenza ifale possono compensare le carenze nel passo iniziale di attacco di spora. Al contrario, in condizioni di promuovere l&#39;adesione di conidi di &Delta;alb1 di superfici polimeriche le forme mutanti pi&ugrave; stabili biofilm rispetto al tipo di selvatico, suggerendo che adesione iniziale spora supporta la crescita sessile.

Il ruolo dell&#39;adesione iniziale spora in formazione di pellet e biofilm in Aspergillus niger.

&#x83CC;&#x985E;&#x306F;&#x3001;&#x7121;&#x6A5F;&#x30FB;&#x6709;&#x6A5F;&#x6750;&#x6599;&#x306E;&#x591A;&#x7A2E;&#x591A;&#x69D8;&#x306A;&#x6210;&#x9577;&#x3057;&#x307E;&#x3059;&#x3002;&#x7D30;&#x80DE;&#x9593;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x306E;&#x80DE;&#x5B50;&#x3084;&#x83CC;&#x7CF8;&#x83CC;&#x7CF8;&#x4E09;&#x6B21;&#x5143;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x3084;&#x30D0;&#x30A4;&#x30AA; &#x30D5;&#x30A3;&#x30EB;&#x30E0;&#x306A;&#x3069;&#x306E;&#x958B;&#x767A;&#x306E;&#x305F;&#x3081;&#x306E;&#x524D;&#x63D0;&#x6761;&#x4EF6;&#x3067;&#x3059;&#x304C;&#x30B3;&#x30ED;&#x30CB;&#x30FC;&#x306E;&#x78BA;&#x7ACB;&#x304A;&#x3088;&#x3073;&#x6210;&#x9577;&#x56FA;&#x4F53;&#x8868;&#x9762;&#x4E0A;&#x306E;&#x80DE;&#x5B50;&#x3068;&#x83CC;&#x7CF8;&#x3001;&#x57FA;&#x677F;&#x3078;&#x306E;&#x5BC6;&#x7740;&#x6027;&#x304C;&#x5FC5;&#x8981;&#x3067;&#x3059;&#x3002;&#x8868;&#x9762;&#x4ED8;&#x7740;&#x306B;&#x3088;&#x308B;&#x3055;&#x3089;&#x306A;&#x308B;&#x63A5;&#x7740;&#x6210;&#x5F62;&#x767A;&#x82BD;&#x7BA1;&#x3068;&#x62E1;&#x5927;&#x306E;&#x83CC;&#x7CF8;&#x306E;&#x7D9A;&#x304F;&#x5206;&#x751F;&#x80DE;&#x5B50;&#x306E;&#x521D;&#x671F;&#x306E;&#x6DFB;&#x4ED8;&#x30D5;&#x30A1;&#x30A4;&#x30EB;&#x3067;&#x69CB;&#x6210;&#x3055;&#x308C;&#x3066; 2 &#x6BB5;&#x968E;&#x306E;&#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x3068;&#x3057;&#x3066;&#x8A18;&#x8F09;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x672C;&#x7814;&#x7A76;&#x3067;&#x306F;&#x3001;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x3092;&#x672A;&#x767A;&#x82BD;&#x306E;&#x80DE;&#x5B50;&#x3068;&#x30D0;&#x30A4;&#x30AA; &#x30D5;&#x30A3;&#x30EB;&#x30E0;&#x5F62;&#x6210;&#x30B3;&#x30A6;&#x30B8;&#x30AB;&#x30D3; &#x30CB;&#x30B8;&#x30A7;&#x30FC;&#x30EB;&#x3067;&#x306E;&#x63A5;&#x7740;&#x306E;&#x8CA2;&#x732E;&#x5EA6;&#x3092;&#x5206;&#x6790;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x30E1;&#x30E9;&#x30CB;&#x30F3;&#x751F;&#x5408;&#x6210;&#x7A81;&#x7136;&#x5909;&#x7570; alb1 &#x907A;&#x4F1D;&#x5B50;&#x306E;&#x524A;&#x9664;&#x306B;&#x3088;&#x3063;&#x3066;&#x3001;&#x30DD;&#x30EA;&#x30B1;&#x30BF;&#x30A4;&#x30C9;&#x5408;&#x6210;&#x9175;&#x7D20;&#x306E;&#x8272;&#x7D20;&#x306E;&#x751F;&#x5408;&#x6210;&#x306E;&#x5FC5;&#x9808;&#x30A8;&#x30F3;&#x30B3;&#x30FC;&#x30C7;&#x30A3;&#x30F3;&#x30B0;&#x306B;&#x5EFA;&#x8A2D;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;&Delta;alb1 &#x80DE;&#x5B50;&#x306F;&#x3001;&#x8868;&#x9762;&#x69CB;&#x9020;&#x306E;&#x5909;&#x5316;&#x304C;&#x3042;&#x308A;&#x8868;&#x9762;&#x7269;&#x6027;&#x3092;&#x5909;&#x66F4;&#x3057;&#x307E;&#x3059;&#x3002;&#x80DE;&#x5B50;&#x96C6;&#x7D04;&#x80DE;&#x5B50;&#x8868;&#x9762;&#x6DFB;&#x4ED8;&#x30D5;&#x30A1;&#x30A4;&#x30EB;&#x3068;&#x540C;&#x69D8;&#x306B;&#x6DB2;&#x4F53;&#x57F9;&#x990A;&#x3067;&#x7570;&#x306A;&#x308B;&#x91CE;&#x751F;&#x578B;&#x3068;&#x5909;&#x7570;&#x4F53;&#x9593;&#x306F; pH &#x4F9D;&#x5B58;&#x7684;&#x306B;&#x3002;&#x6DB2;&#x4F53;&#x6587;&#x5316;&#x3055;&#x3089;&#x306B;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x306E;&#x5F62;&#x6210;&#x306F;&#x751F;&#x6B96;&#x7BA1;&#x3068;&#x83CC;&#x7CF8;&#x306E;&#x4ED8;&#x7740;&#x80DE;&#x5B50;&#x306E;&#x6DFB;&#x4ED8;&#x30D5;&#x30A1;&#x30A4;&#x30EB;&#x306E;&#x6700;&#x521D;&#x306E;&#x30B9;&#x30C6;&#x30C3;&#x30D7;&#x306E;&#x4E0D;&#x5099;&#x3092;&#x88DC;&#x3046;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x307E;&#x3059;&#x3092;&#x793A;&#x3059;&#x5909;&#x66F4;&#x3055;&#x308C;&#x305F;&#x80DE;&#x5B50;&#x304C;&#x80DE;&#x5B50;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x306B;&#x3088;&#x3063;&#x3066;&#x5F71;&#x97FF;&#x3092;&#x53D7;&#x3051;&#x308B;&#x3067;&#x3059;&#x3002;&#x5BFE;&#x7167;&#x7684;&#x306B;&#x3001;&Delta;alb1 &#x5206;&#x751F;&#x5B50;&#x9AD8;&#x5206;&#x5B50;&#x8868;&#x9762;&#x3078;&#x306E;&#x63A5;&#x7740;&#x3092;&#x4FC3;&#x9032;&#x3059;&#x308B;&#x6761;&#x4EF6;&#x306E;&#x4E0B;&#x3067;&#x7A81;&#x7136;&#x5909;&#x7570;&#x4F53;&#x306E;&#x30D5;&#x30A9;&#x30FC;&#x30E0;&#x3088;&#x308A;&#x30D0;&#x30A4;&#x30AA; &#x30D5;&#x30A3;&#x30EB;&#x30E0;&#x521D;&#x671F;&#x80DE;&#x5B50;&#x63A5;&#x7740;&#x7121;&#x67C4;&#x306E;&#x6210;&#x9577;&#x3092;&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3059;&#x308B;&#x3053;&#x3068;&#x3092;&#x793A;&#x5506;&#x306F;&#x91CE;&#x751F;&#x578B;&#x3088;&#x308A;&#x3082;&#x5B89;&#x5B9A;&#x3002; &#x306B;&#x3057;&#x307E;&#x3059;&#x3002;

&#x30B3;&#x30A6;&#x30B8;&#x30AB;&#x30D3; &#x30CB;&#x30B8;&#x30A7;&#x30FC;&#x30EB;&#x306B;&#x304A;&#x3051;&#x308B;&#x30DA;&#x30EC;&#x30C3;&#x30C8;&#x3068;&#x30D0;&#x30A4;&#x30AA; &#x30D5;&#x30A3;&#x30EB;&#x30E0;&#x5F62;&#x6210;&#x306B;&#x304A;&#x3051;&#x308B;&#x521D;&#x671F;&#x80DE;&#x5B50;&#x4ED8;&#x7740;&#x306E;&#x5F79;&#x5272;&#x3002;

&#xB2E4;&#xC591; &#xD55C; &#xC720;&#xAE30; &#xBC0F; &#xBB34;&#xAE30; &#xC7AC;&#xB8CC;&#xC5D0; &#xACF0; &#xD321;&#xC774; &#xC131;&#xC7A5;. &#xC2DD;&#xBBFC;&#xC9C0; &#xC124;&#xB9BD; &#xBC0F; &#xACE0;&#xCCB4; &#xD45C;&#xBA74;&#xC5D0; &#xC131;&#xC7A5; &#xC140; &#xD3EC;&#xC790; &#xB610;&#xB294; &#xADE0; &#xC0AC;&#xC774; &#xC0C1;&#xD638; &#xC791;&#xC6A9;&#xC740; &#xD3A0; &#xB9BF; &#xB610;&#xB294; biofilms &#xAC19;&#xC740; 3 &#xCC28;&#xC6D0; &#xC0AC;&#xCCB4; &#xAD6C;&#xC870; &#xAC1C;&#xBC1C;&#xC744; &#xC704;&#xD55C; &#xC804;&#xC81C; &#xC870;&#xAC74; &#xD3EC;&#xC790;&#xC640; &#xADE0; &#xAE30;&#xD310;&#xC5D0;&#xC758; &#xC811;&#xCC29; &#xB825;&#xC774; &#xD544;&#xC694; &#xD569;&#xB2C8;&#xB2E4;. &#xD45C;&#xBA74; &#xBC00;&#xCC29; ungerminated conidia &#xB4A4;&#xC5D0; &#xCD94;&#xAC00; &#xC811;&#xCC29; &#xB825;&#xC744; &#xD615;&#xC131; &#xC138;&#xADE0; &#xD29C;&#xBE0C; &#xBC0F; &#xC131;&#xC7A5; &#xD558; &#xACE0; &#xC788;&#xB294; &#xADE0;&#xC758; &#xCD08;&#xAE30; &#xBD80;&#xCC29;&#xC73C;&#xB85C; &#xC774;&#xB8E8;&#xC5B4;&#xC9C4; 2 &#xB2E8;&#xACC4; &#xACFC;&#xC815;&#xC73C;&#xB85C; &#xC124;&#xBA85; &#xD558;&#xACE0;&#xC788;&#xB2E4;. &#xD604;&#xC7AC;&#xC758; &#xC5F0;&#xAD6C;&#xC5D0;&#xC11C; &#xC6B0;&#xB9AC;&#xB294; &#xD3A0; &#xB81B;&#xC744; ungerminated &#xD3EC;&#xC790;&#xC640; Aspergillus &#xB2C8;&#xC81C;&#xB974;&#xC5D0;&#xC11C; biofilm &#xD615;&#xC131;&#xC758; &#xC811;&#xCC29;&#xC758; &#xAE30;&#xC5EC;&#xB97C; &#xBD84;&#xC11D; &#xD588;&#xB2E4;. &#xBA5C; &#xB77C; &#xB2CC; &#xC0DD; &#xD569;&#xC131; &#xACB0;&#xD54D; &#xB3CC;&#xC5F0;&#xBCC0;&#xC774; polyketide synthase &#xC0C9;&#xC18C;&#xC758; &#xC0DD; &#xD569;&#xC131;&#xC5D0; &#xD544;&#xC218;&#xC801;&#xC778; &#xC778;&#xCF54;&#xB529; alb1 &#xC720;&#xC804;&#xC790;&#xC758; &#xC0AD;&#xC81C;&#xC5D0; &#xC758;&#xD574; &#xAC74;&#xC124; &#xB418;&#xC5C8;&#xB2E4;. &Delta;alb1 conidia &#xBCC0;&#xACBD; &#xB41C; &#xD45C;&#xBA74; &#xAD6C;&#xC870; &#xBC0F; &#xBB3C;&#xB9AC; &#xD654;&#xD559;&#xC801; &#xD45C;&#xBA74; &#xC18D;&#xC131; &#xBCC0;&#xACBD;. &#xC561;&#xCCB4; &#xBB38;&#xD654; &#xD3EC;&#xC790; &#xD45C;&#xBA74; &#xCCA8;&#xBD80; &#xD30C;&#xC77C;&#xC5D0; &#xC9D1;&#xACC4; &#xD3EC;&#xC790; pH &#xC758;&#xC874; &#xBC29;&#xC2DD;&#xC5D0;&#xC11C; &#xC57C;&#xC0DD; &#xC885;&#xB958;&#xC640; &#xB3CC;&#xC5F0;&#xBCC0;&#xC774; &#xC0AC;&#xC774; &#xB2E4;. &#xC561;&#xCCB4; &#xBB38;&#xD654; &#xB354; &#xD3A0; &#xB81B;&#xC5D0; &#xD615;&#xC131; &#xC138;&#xADE0; &#xD29C;&#xBE0C; &#xBC0F; hyphal &#xC900;&#xC218; &#xD3EC;&#xC790; &#xCCA8;&#xBD80; &#xD30C;&#xC77C;&#xC758; &#xCD08;&#xAE30; &#xB2E8;&#xACC4;&#xC5D0;&#xC11C; &#xACB0;&#xD568;&#xC5D0; &#xB300; &#xD55C; &#xBCF4;&#xC0C1; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4; &#xB098;&#xD0C0;&#xB0B4;&#xB294; &#xBCC0;&#xACBD; &#xB41C; &#xC2A4; &#xD3EC;&#xC5B4; &#xC2A4; &#xD3EC;&#xC5B4; &#xC0C1;&#xD638; &#xC791;&#xC6A9;&#xC5D0; &#xC758;&#xD574; &#xC601;&#xD5A5;&#xC744; &#xBC1B;&#xC9C0; &#xC54A;&#xC2B5;&#xB2C8;&#xB2E4;. &#xB300;&#xC870;&#xC801;&#xC73C;&#xB85C;, &Delta;alb1 conidia &#xD3F4;&#xB9AC;&#xBA38; &#xD45C;&#xBA74;&#xC5D0; &#xC811;&#xCC29;&#xC744; &#xD64D;&#xBCF4; &#xD558;&#xB294; &#xC870;&#xAC74; &#xD558;&#xC5D0;&#xC11C; &#xB3CC;&#xC5F0;&#xBCC0;&#xC774; &#xD615;&#xD0DC; &#xBCF4;&#xB2E4; &#xC548;&#xC815;&#xC801;&#xC778; biofilms &#xCD08;&#xAE30; &#xD3EC;&#xC790; &#xC811;&#xCC29; &#xCC29; &#xC131;&#xC7A5;&#xC744; &#xC9C0;&#xC6D0; &#xC81C;&#xC548; &#xC57C;&#xC0DD; &#xD0C0;&#xC785; &#xBCF4;&#xB2E4;.

&#xCD08;&#xAE30; &#xD3EC;&#xC790; &#xC811;&#xCC29; &#xB204; &#xB2C8;&#xC81C;&#xB974;&#xC5D0;&#xC11C; &#xD3A0; &#xB9BF; &#xBC0F; biofilm &#xD615;&#xC131;&#xC5D0;&#xC758; &#xC5ED;&#xD560;.

Hongos crecen en una gran variedad de materiales org&aacute;nicos e inorg&aacute;nicos. Establecimiento de la Colonia y el crecimiento en las superficies s&oacute;lidas requieren adhesi&oacute;n de esporas e hifas al substrato, mientras que las interacciones c&eacute;lula a c&eacute;lula entre esporas o hifas son un requisito previo para el desarrollo de estructuras tridimensionales miceliales como bolitas o biofilms. Adherencia superficial ha sido descrito como un proceso de dos pasos, compuesto por la fijaci&oacute;n inicial de conidios ungerminated seguida de m&aacute;s adherencia de los tubos de germen formando y crecientes hifas. En el presente estudio, analizamos la contribuci&oacute;n de adhesi&oacute;n de esporas ungerminated de pellets y la formaci&oacute;n de biopel&iacute;culas de Aspergillus niger. Mutantes deficientes en la bios&iacute;ntesis de melanina fueron construidos por la supresi&oacute;n del gen alb1, codificaci&oacute;n un polic&eacute;tido sintasa esencial para la bios&iacute;ntesis de pigmento. Conidios de &Delta;alb1 tienen una estructura superficial alterada y cambiaron propiedades fisicoqu&iacute;micas de la superficie. Agregaci&oacute;n de espora en cultivo l&iacute;quido as&iacute; como accesorio superficie espora difieren en el tipo salvaje y mutante en una forma dependiente de pH. En pellets m&aacute;s cultivo l&iacute;quido formaci&oacute;n se ve afectada por interacciones alterada espora-espora, indicando que tubo de germen y adherencia hifal pueden compensar las deficiencias en el paso inicial del accesorio de la espora. En cambio, en condiciones de promover la adhesi&oacute;n de conidios de &Delta;alb1 a las superficies de pol&iacute;mero las formas mutantes m&aacute;s estable biofilms que el tipo salvaje, sugiriendo que la adhesi&oacute;n inicial de la espora apoya crecimiento s&eacute;sil.

El papel de la adhesi&oacute;n de esporas inicial en la formaci&oacute;n de pellets y biofilm en Aspergillus niger.

Filamentous fungi have been widely applied in industrial biotechnology for many decades. In submerged culture processes, they typically exhibit a complex morphological life cycle that is related to production performance--a link that is of high interest for process optimization. The fungal forms can vary from dense spherical pellets to viscous mycelia. The resulting morphology has been shown to be influenced strongly by process parameters, including power input through stirring and aeration, mass transfer characteristics, pH value, osmolality and the presence of solid micro-particles. The surface properties of fungal spores and hyphae also play a role. Due to their high industrial relevance, the past years have seen a substantial development of tools and techniques to characterize the growth of fungi and obtain quantitative estimates on their morphological properties. Based on the novel insights available from such studies, more recent studies have been aimed at the precise control of morphology, i.e., morphology engineering, to produce superior bio-processes with filamentous fungi.

Characterization and control of fungal morphology for improved production performance in biotechnology.

The mechanical properties of aggregated colloids depend on the mutual interplay of inter-particle potentials, contact forces, aggregate structure and material properties of the bare particles. Owing to this variety of influences, experimental results from macroscopic mechanical testings were mostly compared to time-consuming, microscopic simulations rather than to analytical theories. The aim of the present paper was to relate both macroscopic and microscopic mechanical data with each other and simple analytical models. We investigated dense amorphous aggregates made from monodisperse poly-methyl methacrylate (PMMA) particles (diameter: 1.6 μm via nanoindentation in combination with confocal microscopy. The resulting macroscopic information was complemented by the three-dimensional aggregate structure as well as the microscopic strain field and strain tensor. The measured strain field and tensor were in reasonable agreement with the predictions from analytical continuum theories. Consequently, the measured force-depth curves could be analyzed within a theoretical framework that had been frequently used for nanoindentation of atomic matter such as metals, ceramics and polymers. The extracted values for hardness and effective Young's modulus represented average values characteristic of the aggregate. On the basis of of these parameters we discuss the influence of the strength of particle bonds by introducing polystyrene (PS) between the particles.

Colloidal aggregates tested via nanoindentation and quasi-simultaneous 3D imaging.

Planetary ball mills are well known and used for particle size reduction on laboratory and pilot scales for decades while during the last few years the application of planetary ball mills has extended to mechanochemical approaches. Processes inside planetary ball mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding balls, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary ball mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary ball mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary ball mills on the energy entry. In addition the imaging of motion patterns inside a planetary ball mill from simulations and video recordings is shown.

Process engineering with planetary ball mills.

Particulate coatings are used in a wide range of technical applications. The application affecting properties of these coatings depend strongly on the structure formation along the production process. Thus, primary and secondary particle size, size distribution, particle morphology as well as the particle-particle and particle-fluid interactions of the used formulation affect the resulting coating properties.

Influence of electrostatic particle interactions on the properties of particulate coatings of titanium dioxide.

The effect of medium pH on conidial aggregation during submerged cultivation of Aspergillus niger is considered to originate from the electrostatic surface properties of the spores. As previously shown, these properties are greatly influenced by the presence of a melanin-containing surface coating covering the outer spore wall layer. The present study was designed to elucidate the impact of such a coating on the spores' surface potential and their electrostatic repulsion under acidic conditions. A Poisson-Boltzmann model was proposed and potential profiles across the surface coating of noninteracting and interacting spores were calculated. The surface potentials thus obtained were in line with the observed pH dependence of the zeta potential. This dependence was consistent with the outcome of aggregation experiments. Apparently contradictory results regarding the zeta potential and the aggregation behavior of the spores were obtained when the ionic strength was varied. However, both of these observations could be explained by the model.

Arno Kwade

Institute for Particle Technology

Technische Universität Braunschweig

Development of an Experimental Setup for the Measurement of the Coefficient of Restitution under Vacuum Conditions

Arno Kwade

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institute for Particle Technology

Technische Universität Braunschweig

Development of an Experimental Setup for the Measurement of the Coefficient of Restitution under Vacuum Conditions

Institute for Particle Technology