Name: determining the ice-binding planes of antifreeze proteins by fluorescence-based ice plane affinity
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PLD担任加拿大蛋白质工程研究主席。这项工作由加拿大卫生研究所向民盟提供的赠款资助。这项工作还得到了日本科学促进协会（JSPS）和日本生物导向技术研究促进机构（BRAIN）的科学研究资助。我们感谢克里斯·马歇尔博士和迈克·奎珀博士开创性的工作，导致FIPA。我们还感谢萨凯·齐达博士为这项工作提供设施，并感谢劳里·格雷厄姆博士为荧光灯激发和排放过滤器的建立提供便利。

1. 生长单一冰晶
<ol><li>拿一个干净的金属锅（直径15厘米，高4.5厘米），适合，可以漂浮在乙烯乙二醇冷却浴。</li>
	<li>准备聚氯乙烯 （PVC） 圆柱形模具，直径 4.5 厘米，高 3-4 厘米，厚 4 毫米），从管道锯断面。<ol>
<li>一侧切一个档次（1毫米宽，2毫米高）（图1A）。</li>
		<li>准备尽可能多的模具，可以舒适地放入锅（图1B）。 注：一项研究表明，聚乙烯醇（PVA）可?...

<ol>
	<li>Devries, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antifreeze+peptides+and+glycopeptides+in+cold-water+fishes.">Antifreeze peptides and glycopeptides in cold-water fishes.</a> Annu. Rev. Physiol. 45, 245-260 (1983).</li><li>Sidebottom, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phytochemistry+-+heat-stable+antifreeze+protein+from+grass.">Phytochemistry - heat-stable antifreeze protein from grass.</a> Nature. 406 (6793), 256-256 (2000).</li><li>Tomczak, M. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mechanism+for+stabilization+of+membranes+at+low+temperatures+by+an+antifreeze+protein.">A mechanism for stabilization of membranes at low temperatures by an antifreeze protein.</a> Biophys. J. 82 (2), 874-881 (2002).</li><li>Gilbert, J. A., Davies, P. L., Laybourn-Parry, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperactive+Ca2+-dependent+antifreeze+protein+in+an+antarctic+bacterium.">Hyperactive Ca2+-dependent antifreeze protein in an antarctic bacterium.</a> FEMS Microbiol. Lett. 245 (1), 67-72 (2005).</li><li>Garnham, C. P., Campbell, R. L., Davies, P. 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U.S.A. 74 (6), 2589-2593 (1977).</li><li>Baardsnes, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+ice-binding+face+for+type+i+antifreeze+protein.">New ice-binding face for type i antifreeze protein.</a> FEBS Lett. 463 (1-2), 87-91 (1999).</li><li>Middleton, A. J., Brown, A. M., Davies, P. L., Walker, V. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+the+ice-binding+face+of+a+plant+antifreeze+protein.">Identification of the ice-binding face of a plant antifreeze protein.</a> FEBS Lett. 583 (4), 815-819 (2009).</li><li>Garnham, C. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compound+ice-binding+site+of+an+antifreeze+protein+revealed+by+mutagenesis+and+fluorescent+tagging.">Compound ice-binding site of an antifreeze protein revealed by mutagenesis and fluorescent tagging.</a> Biochemistry. 49 (42), 9063-9071 (2010).</li><li>Nutt, D. R., Smith, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual+function+of+the+hydration+layer+around+an+antifreeze+protein+revealed+by+atomistic+molecular+dynamics+simulations.">Dual function of the hydration layer around an antifreeze protein revealed by atomistic molecular dynamics simulations.</a> J. Am. Chem. Soc. 130 (39), 13066-13073 (2008).</li><li>Knight, C. A., Cheng, C. C., Devries, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adsorption+of+alpha-helical+antifreeze+peptides+on+specific+ice+crystal-surface+planes.">Adsorption of alpha-helical antifreeze peptides on specific ice crystal-surface planes.</a> Biophys. J. 59 (2), 409-418 (1991).</li><li>Antson, A. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+the+mechanism+of+ice+binding+by+type+iii+antifreeze+proteins.">Understanding the mechanism of ice binding by type iii antifreeze proteins.</a> J. Mol. Biol. 305 (4), 875-889 (2001).</li><li>Graether, S. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beta-helix+structure+and+ice-binding+properties+of+a+hyperactive+antifreeze+protein+from+an+insect.">Beta-helix structure and ice-binding properties of a hyperactive antifreeze protein from an insect.</a> Nature. 406 (6793), 325-328 (2000).</li><li>Pertaya, N., Marshall, C. B., Celik, Y., Davies, P. L., Braslavsky, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+visualization+of+spruce+budworm+antifreeze+protein+interacting+with+ice+crystals:+Basal+plane+affinity+confers+hyperactivity.">Direct visualization of spruce budworm antifreeze protein interacting with ice crystals: Basal plane affinity confers hyperactivity.</a> Biophys. J. 95 (1), 333-341 (2008).</li><li>Middleton, A. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antifreeze+protein+from+freeze-tolerant+grass+has+a+beta-roll+fold+with+an+irregularly+structured+ice-binding+site.">Antifreeze protein from freeze-tolerant grass has a beta-roll fold with an irregularly structured ice-binding site.</a> J. Mol. Biol. 416 (5), 713-724 (2012).</li><li>Scotter, A. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+basis+for+hyperactivity+of+antifreeze+proteins.">The basis for hyperactivity of antifreeze proteins.</a> Cryobiology. 53 (2), 229-239 (2006).</li><li>Knight, C. A., Wierzbicki, A., Laursen, R. A., Zhang, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adsorption+of+biomolecules+to+ice+and+their+effects+upon+ice+growth.+1.+Measuring+adsorption+orientations+and+initial+results.">Adsorption of biomolecules to ice and their effects upon ice growth. 1. Measuring adsorption orientations and initial results.</a> Crys. Growth Des. 1 (6), 429-438 (2001).</li><li>Hakim, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystal+structure+of+an+insect+antifreeze+protein+and+its+implications+for+ice+binding.">Crystal structure of an insect antifreeze protein and its implications for ice binding.</a> J. Biol. Chem. 288 (17), 12295-12304 (2013).</li><li>Garnham, C. P., Nishimiya, Y., Tsuda, S., Davies, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+a+naturally+inactive+isoform+of+type+iii+antifreeze+protein+into+one+that+can+stop+the+growth+of+ice.">Engineering a naturally inactive isoform of type iii antifreeze protein into one that can stop the growth of ice.</a> FEBS Lett. 586 (21), 3876-3881 (2012).</li><li>Holt, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+antifreeze+proteins+and+poly(vinyl+alcohol)+on+the+nucleation+of+ice:+A+preliminary+study.">The effect of antifreeze proteins and poly(vinyl alcohol) on the nucleation of ice: A preliminary study.</a> Cryo Letters. 24 (5), 323-330 (2003).</li><li>Knight, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+technique+for+growing+large,+optically+''perfect''+ice+crystals.">A simple technique for growing large, optically ''perfect'' ice crystals.</a> J. Glac. 42 (142), 585-587 (1996).</li><li>Hobbs, P. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Ice physics. , 200-248 (1974).</li><li>Knight, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+crystallographic+etch+pits+on+ice,+and+its+application+to+the+study+of+hailstones.">Formation of crystallographic etch pits on ice, and its application to the study of hailstones.</a> J. Appl. Meteorol. 5 (5), 710-714 (1966).</li><li>Yang, D. S., Sax, M., Chakrabartty, A., Hew, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystal+structure+of+an+antifreeze+polypeptide+and+its+mechanistic+implications.">Crystal structure of an antifreeze polypeptide and its mechanistic implications.</a> Nature. 333 (6170), 232-237 (1988).</li><li>Sicheri, F., Yang, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ice-binding+structure+and+mechanism+of+an+antifreeze+protein+from+winter+flounder.">Ice-binding structure and mechanism of an antifreeze protein from winter flounder.</a> Nature. 375 (6530), 427-431 (1995).</li><li>Devries, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+glycopeptides+and+peptides+in+inhibition+of+crystallization+of+water+in+polar+fishes.">Role of glycopeptides and peptides in inhibition of crystallization of water in polar fishes.</a> Philos. T Roy. Soc. B. 304 (1121), 575-588 (1984).</li><li>Pertaya, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence+microscopy+evidence+for+quasi-permanent+attachment+of+antifreeze+proteins+to+ice+surfaces.">Fluorescence microscopy evidence for quasi-permanent attachment of antifreeze proteins to ice surfaces.</a> Biophys. J. 92 (10), 3663-3673 (2007).</li><li>Kondo, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ice-binding+site+of+snow+mold+fungus+antifreeze+protein+deviates+from+structural+regularity+and+high+conservation.">Ice-binding site of snow mold fungus antifreeze protein deviates from structural regularity and high conservation.</a> Proc. Natl. Acad. Sci. U.S.A. 109 (24), 9360-9365 (2012).</li><li>Mok, Y. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+basis+for+the+superior+activity+of+the+large+isoform+of+snow+flea+antifreeze+protein.">Structural basis for the superior activity of the large isoform of snow flea antifreeze protein.</a> Biochemistry. 49 (11), 2593-2603 (2010).</li><li>Takamichi, M., Nishimiya, Y., Miura, A., Tsuda, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fully+active+qae+isoform+confers+thermal+hysteresis+activity+on+a+defective+sp+isoform+of+type+iii+antifreeze+protein.">Fully active qae isoform confers thermal hysteresis activity on a defective sp isoform of type iii antifreeze protein.</a> FEBS J. 276 (5), 1471-1479 (2009).</li><li>Bar-Dolev, M., Celik, Y., Wettlaufer, J. S., Davies, P. L., Braslavsky, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+insights+into+ice+growth+and+melting+modifications+by+antifreeze+proteins.">New insights into ice growth and melting modifications by antifreeze proteins.</a> J. R. Soc. Interface. 9 (77), 3249-3259 (2012).</li><li>Celik, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic+experiments+reveal+that+antifreeze+proteins+bound+to+ice+crystals+suffice+to+prevent+their+growth.">Microfluidic experiments reveal that antifreeze proteins bound to ice crystals suffice to prevent their growth.</a> Proc. Natl. Acad. Sci. U.S.A. 110 (4), 1309-1314 (2013).</li><li>Garnham, C. P., Campbell, R. L., Walker, V. K., Davies, P. 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查尔斯·奈特研制的冰蚀方法，用于确定法新社的冰平面，大大推进了对AFP冰结合机理的研究。虽然AFP的结构可以通过X射线晶体学26，27 来解决，但没有明显的方法来推断AFP绑定在冰上的互补表面。当I型法新社从冬季比目鱼的最初特征，它被假设绑定到冰28的主要棱镜平面。然而，奈特的破冰实验I型法新社显示，他们与冰13金字塔平面结合。这一结果促使法新社研究界重?...

抗冻蛋白（AFPs）的产生是生活在冰层中环境中的一些生物体的重要生存机制。直到最近，人们还认为AFP的唯一功能是防止或减缓内部冰晶的生长，这些冰晶会阻断循环，造成组织损伤和渗透应激。不能容忍任何程度的冰冻的生物，如鱼，表达AFP，以完全抑制冰晶生长1。其他，如草，是耐冻和表达AFP，以抑制冰的再封装，减少形成大冰晶在他们的组织2。在低温下稳定膜是另一个功能，建议为AFP3。最近，一个新的角色被建议为法新社的南极细菌， 马里诺莫纳斯原始，从冰覆盖的咸水湖4。这个AFP是一个更大的粘合蛋白5的一部分，被认为是附加细菌到冰上，以更好地获得氧气和营养物质6。其他微生物已知分泌AFP，这可能改变它们生活7的冰的结构。
在一些鱼类、昆虫、植物、藻类、细菌、硅藻和真菌中发现了AFP。它们具有显著不同的序列和结构，与不同祖先在不同场合的进化相一致：然而，它们都与冰结合，并通过吸附抑制机制8抑制其生长。AFP各有一个特定的表面，作为其冰结合点（IBS）。这些通常通过9-11表面残留物的现场定向突变来识别。IBS 假设将水分子排列在与特定冰平面相匹配的冰样图案中。因此，法新社形成其配体之前，绑定到它5，12。冰飞机可以通过米勒指数来定义，不同的AFP可以与不同的平面结合。因此，I型法新社从冬季比目鱼绑定到20-21金字塔平面13，III型法新社结合主棱镜和金字塔平面使用复合冰结合表面11，14，而云杉芽虫法新社，一个过度活跃的法新社，同时结合到主平面和基底平面15，16。其他过度活跃的AFP，如 MpAFP，与多个冰平面结合，如它们对单个冰晶半球5，17的完全覆盖所示。据推测，超活性AFP结合基底平面和其他飞机的能力，可能占其活性的10倍，比适度活跃的AFP18。虽然超活性AFP的效率是有据可查的，但它们与多个冰层结合的能力仍然不为人所知。
确定法新社飞往冰上飞机的最初方法是由查尔斯·奈特13，19开发的。在这种方法中，一个宏观的单一冰晶被安装在一个空心金属棒（冷手指）上，通过将其浸入装满脱气水的半球杯中形成半球。然后，半球被淹没在AFP的稀释溶液中，在几个小时内，由通过冷手指循环的乙二醇温度控制，从法新社溶液中长出一层冰到冰晶半球。冰晶从溶液中取出，从冷手指上分离出来，放置在-10至-15°C的冰柜室中。表面用锋利的刀片刮去防冻蛋白溶液的冷冻表面薄膜，冰晶允许升华至少3小时。升华后，由AFP绑定的冰平面可视为从残余蛋白质中提取的白色蚀刻图案。冰半球可以定向到其 c轴和 斧头，定位冰的基础平面和棱镜平面，并确定蚀刻补丁的米勒指数。
在这里，我们描述了对确定法新社绑定冰平面的原始方法的修改，我们称之为荧光基冰平面亲和力（FIPA）11。AFP 的荧光标记要么带有钟音标签，如绿色荧光蛋白 （GFP）11，16，17，20，要么与荧光染料共价绑定到 AFP5，21。荧光标记的AFP被吸收到一个冰晶中，并且使用与原始冰蚀实验相同的实验程序过度生长。在整个实验中，可以使用紫外线（UV）灯监测与生长的冰半球结合的AFP的程度。实验完成后，半球可以直接从冷手指上取下并成像，无需升华。然而，如果需要，半球可以留给升华，以可视化传统的冰蚀刻。对FIPA方法的修改将传统的冰蚀协议缩短了几个小时。此外，还有可能同时成像几个具有不同荧光标签的 AFP，以可视化 AFP 绑定冰平面的重叠模式。

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			<td height="42" style="height:42px;width:177px;">NESLAB RTE Refrigerating Bath/Circulators</td>
			<td style="width:95px;">Thermo Scientific</td>
			<td style="width:145px;">RTE7</td>
			<td style="width:189px;"></td>
		</tr>
		<tr height="48">
			<td height="48" style="height:48px;width:177px;">Ethylene glycol, Premixed Antifreeze/Coolant</td>
			<td style="width:95px;">Certified</td>
			<td style="width:145px;">29-3037-0</td>
			<td style="width:189px;">Common automotive antifreeze</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:177px;">Cold finger</td>
			<td style="width:95px;">not available</td>
			<td style="width:145px;">not available</td>
			<td style="width:189px;">Custom made with brass (9 cm long, 1.5 cm outer diameter)</td>
		</tr>
		<tr height="67">
			<td height="67" style="height:67px;width:177px;">Hemispherical cup</td>
			<td style="width:95px;">not available</td>
			<td style="width:145px;">not available</td>
			<td style="width:189px;">Custom made with resin (8 cm outer diameter, 6 cm inner diameter)</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:177px;">High Dual Output Lighting System</td>
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			<td style="width:189px;">Additional and custom excitation filters can be purchased from Lightools Research</td>
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			<td height="40" rowspan="2" style="height:40px;width:177px;">Camera</td>
			<td rowspan="2" style="width:95px;">Canon</td>
			<td rowspan="2" style="width:145px;">EOS 50D</td>
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			<td height="79" style="height:79px;width:177px;">Emission Filters</td>
			<td style="width:95px;">Lightools Research</td>
			<td style="width:145px;">LT-9EFPVG, LT-9GFPVG, LT-9RFPVG</td>
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</table>

determining the ice-binding planes of antifreeze proteins by fluorescence-based ice plane affinity

防冻蛋白 （AFP） 表现在各种冷硬生物体中，以防止或减缓内部冰的生长。AFP 通过冰结合表面与特定的冰平面结合。基于荧光的冰平面亲和力 （FIPA） 分析是一种用于确定 AFP 与之结合的冰平面的修改技术。FIPA 基于确定法新社绑定冰平面的原始冰蚀方法。它在缩短的实验时间内产生更清晰的图像。在 FIPA 分析中，AFP 被荧光标记为有幻想标记或共价染料，然后慢慢融入宏观单一冰晶中，该晶体已预制成半球，并定向以确定 a 轴 和 c 轴。法新社的冰半球在紫外线下被成像，使用过滤器来阻挡非特异性光，以可视化法新社的平面。AFP 的荧光标签允许实时监控 AFP 吸附到冰中。已发现这些标签不会影响 AFP 绑定的平面。FIPA 分析还引入了将多个不同标签的 AFP 绑在同一个单一冰晶上的选项，以帮助区分其绑定平面。FIPA的这些应用有助于增进我们对AFP如何与冰结合以阻止其生长的理解，以及为什么许多产生AFF的生物会表达多种AFP等形。

单个冰晶的准备和安装是 FIPA 程序的两个步骤，其中最常出错。确定准备好的冰晶是否为单一的，通过交叉极性体（图1D）检查它，如协议部分的第2.1步所概述。如果用于 FIPA 分析的多晶冰晶，则结果将是非晶体在半球的不连续绑定，而没有连贯的结合模式 （图 6B）。如果冰晶接口位于法新社绑定的冰层周围，最终结果可能无法解释。因此，在进入下一步之前，应仔细检...

Watch this Scientific Journal Video about Determining the Ice-binding Planes of Antifreeze Proteins by Fluorescence-based Ice Plane Affinity at JoVE.com

Determining the Ice-binding Planes of Antifreeze Proteins by Fluorescence-based Ice Plane Affinity

防冻蛋白 （AFP） 与特定的冰平面结合，以防止或减缓冰的生长。基于荧光的冰平面亲和力 （FIPA） 分析是对确定 AFP 绑定冰平面的原始冰蚀刻方法的修改。AFP 采用荧光标记，并融入宏观单一冰晶中，并在紫外线下可视化。

通过荧光基冰平面亲和力确定防冻蛋白的冰结合平面

Antifreeze proteins (AFPs) are expressed in a variety of cold-hardy organisms to prevent or slow internal ice growth. AFPs bind to specific planes of ice ...

Research

JoVE Journal

Chemistry

LabVIEW-operated Novel Nanoliter Osmometer for Ice Binding Protein Investigations

LabVIEW操作的新型纳升渗透压仪冰结合蛋白的调查

Ice-binding proteins (IBPs), including antifreeze proteins, ice structuring proteins, thermal hysteresis proteins, and ice recrystallization inhibition ...

科研

化学

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides

生物分子有序结构由短肽的自组装形成

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control ...

Submillisecond Conformational Changes in Proteins Resolved by Photothermal Beam Deflection

亚毫秒构象变化蛋白的光热光束偏转已解决

Photothermal beam deflection together with photo-acoustic calorimetry and thermal grating belongs to the family of photothermal methods that monitor the ...

Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog

PAD4活动通过亲荧光底物类似物基于荧光监测

Post-translational modifications may lead to altered protein functional states by increasing the covalent variations on the side chains of many protein ...

Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues

优化合成蛋白质：Interpositional依赖性的鉴定指示在结构和/或功能性连接的残留

Protein alignments are commonly used to evaluate the similarity of protein residues, and the derived consensus sequence used for identifying functional ...

In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS

In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS

在水中水合蛋白原位表征SALVI和TOF-SIMS

This work demonstrates in situ characterization of protein biomolecules in the aqueous solution using the System for Analysis at the Liquid Vacuum ...

Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand

分离硫酸选择性结晶用双 -  iminoguanidinium配体

A simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, ...

Determining the Chemical Composition of Corrosion Inhibitor/Metal Interfaces with XPS: Minimizing Post Immersion Oxidation

确定缓蚀剂/金属界面的化学成分与XPS：最小化后浸入氧化

An approach for acquiring more reliable X-ray photoelectron spectroscopy data from corrosion inhibitor/metal interfaces is described. More specifically, ...

An HS-MRM Assay for the Quantification of Host-cell Proteins in Protein Biopharmaceuticals by Liquid Chromatography Ion Mobility QTOF Mass Spectrometry

液相色谱离子迁移 QTOF 质谱测定蛋白质生物中宿主细胞蛋白的 HS-MRM 法

The analysis of low-level (1-100 ppm) protein impurities (e.g., host-cell proteins (HCPs)) in protein biotherapeutics is a challenging assay requiring ...

Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source

Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source

用干冰作为固体 CO2源实现密封容器中的适度压力

Herein is presented a general strategy to perform reactions under mild to moderate CO2 pressures with dry ice. This technique obviates the need for ...