the-multibac-protein-complex-production-platform-at-the-embl

The MultiBac Protein Complex Production Platform at the EMBL

Proteomics  research revealed the impressive complexity of eukaryotic proteomes in  unprecedented detail. It is now a commonly accepted notion that ...

EMBL Grenoble Outstation and Unit of Virus Host Cell Interactions (UVHCI) UMR5322

The human ATP-binding cassette (ABC) transporter ABCB6 is involved in haem-precursor transport across the mitochondrial membrane. The crystal structure of its nucleotide-binding domain (NBD) has been determined in the apo form and in complexes with ADP, with ADP and Mg(2+) and with ATP at high resolution. The overall structure is L-shaped and consists of two lobes, consistent with other reported NBD structures. Nucleotide binding is mediated by the highly conserved Tyr599 and the Walker A motif, and induces notable structural changes. Structural comparison with other structurally characterized NBDs and full-length ABC transporters gives the first insight into the possible catalytic mechanism of ABCB6 and the role of the N-terminal helix alpha(1) in full-length ABCB6.

Structures of the nucleotide-binding domain of the human ABCB6 transporter and its complexes with nucleotides.

Le transporteur ATP-binding cassette (ABC) ABCB6 est impliqu&eacute; dans le transport de l&#39;h&egrave;me-pr&eacute;curseur &agrave; travers la membrane mitochondriale. A d&eacute;termin&eacute; la structure cristalline de son domaine de liaison de nucl&eacute;otides (NBD) sous la forme de l&#39;apo et complexes avec ADP, ADP et Mg(2+) et ATP &agrave; haute r&eacute;solution. La structure g&eacute;n&eacute;rale est en forme de L et se compose de deux lobes, compatibles avec d&#39;autres structures NBD signal&eacute;s. Liaison de nucl&eacute;otides est m&eacute;di&eacute;e par la Tyr599 hautement conserv&eacute;e et le motif de A Walker et induit des changements structurels importants. Comparaison structurelle avec les autres structurellement caract&eacute;ris&eacute; ADNB et pleine longueur transporteurs ABC donne le premier aper&ccedil;u le m&eacute;canisme catalytique possible de ABCB6 et le r&ocirc;le de la alpha(1) d&#39;h&eacute;lice N-terminale en pleine longueur ABCB6.

Structures du domaine liaison nucl&eacute;otidique du transporteur de ABCB6 humain et de ses complexes avec des nucl&eacute;otides.

Il trasportatore umano del ATP-binding cassette (ABC) ABCB6 &egrave; coinvolto nel trasporto di EME-precursore attraverso la membrana mitocondriale. La struttura di cristallo del suo dominio nucleotide-binding (NBD) &egrave; stata determinata in forma apo e nei complessi con ADP, ADP e Mg(2+) e con ATP ad alta risoluzione. La struttura complessiva &egrave; a forma di L e si compone di due lobi, coerente con le altre strutture NBD segnalati. Nucleotide binding &egrave; mediata dal Tyr599 altamente conservata e il motivo A Walker e induce notevoli cambiamenti strutturali. Confronto strutturale con altri strutturalmente caratterizzata NBDs e full-length dei trasportatori ABC d&agrave; il primo spaccato il possibile meccanismo catalitico di ABCB6 e il ruolo del N-terminale elica alpha(1) in ABCB6 full-length.

Strutture del dominio nucleotide-binding del trasportatore umano ABCB6 e suoi complessi con nucleotidi.

In enteropathogenic Yersinia, the expression of several early-phase virulence factors such as invasin is tightly regulated in response to environmental cues. The responsible regulatory network is complex, involving several regulatory RNAs and proteins such as the LysR-type transcription regulator (LTTR) RovM. In this study, the crystal structure of the effector-binding domain (EBD) of RovM, the first LTTR protein described as being involved in virulence regulation, was determined at a resolution of 2.4â€…Ã…. Size-exclusion chromatography and comparison with structures of full-length LTTRs show that RovM is most likely to adopt a tetrameric arrangement with two distant DNA-binding domains (DBDs), causing the DNA to bend around it. Additionally, a cavity was detected in RovM which could bind small inducer molecules.

Structure of the effector-binding domain of the LysR-type transcription factor RovM from Yersinia pseudotuberculosis.

Dans Yersinia ent&eacute;ropathog&egrave;ne, l&#39;expression de plusieurs facteurs de virulence de premi&egrave;res phases telles qu&#39;invasin est &eacute;troitement contr&ocirc;l&eacute;e en r&eacute;ponse &agrave; des stimuli environnementaux. Le r&eacute;seau de r&eacute;gulation responsable est complex, impliquant plusieurs ARN r&eacute;glementaires et des prot&eacute;ines comme le LysR-type r&eacute;gulateur de la transcription (r) RovM. Dans cette &eacute;tude, la structure cristalline du domaine effecteur-liaison (EBD) de RovM, la premi&egrave;re prot&eacute;ine r, d&eacute;crite comme &eacute;tant impliqu&eacute;s dans la r&eacute;gulation de la virulence, a &eacute;t&eacute; d&eacute;termin&eacute;e avec une r&eacute;solution de 2,4 &Aring;. chromatographie d&#39;exclusion st&eacute;rique et comparaison avec les structures de pleine longueur LTTRs montrent que RovM est plus susceptible d&#39;adopter un t&eacute;tram&egrave;re arrangement comporte deux domaines &eacute;loign&eacute;s de la liaison &agrave; l&#39;ADN (DBDs), provoquant l&#39;ADN de plier autour d&#39;elle. En outre, une cavit&eacute; a &eacute;t&eacute; d&eacute;tect&eacute;e dans RovM qui pourrait lier les mol&eacute;cules de petit inducteur.

Structure du domaine effecteur-liaison du facteur de transcription LysR-type RovM de Yersinia pseudotuberculosis.

In Yersinia enteropatogeno, l&#39;espressione di diversi fattori di virulenza di fase in anticipo come invasin &egrave; strettamente regolato in risposta a stimoli ambientali. Responsabile rete regolamentare &egrave; complessa, che coinvolge diverse normative RNAs e proteine come il regolatore della trascrizione di LysR-tipo (LTTR) RovM. In questo studio, &egrave; stata determinata la struttura cristallina del dominio effector-associazione (EBD) di RovM, la prima proteina LTTR descritta come essere coinvolto nella regolazione di virulenza, con una risoluzione di 2.4 &Aring;. Size exclusion chromatography e confronto con le strutture del full-length LTTRs dimostrare che RovM &egrave; pi&ugrave; probabile ad adottare una disposizione tetramerica con due domini di DNA-binding distanti (DBDs), causando il DNA di piegare intorno ad esso. Inoltre, &egrave; stata rilevata una cavit&agrave; in RovM che potrebbe legare induttore piccole molecole.

Matthias Haffke

EMBL Grenoble Outstation and Unit of Virus Host Cell Interactions (UVHCI) UMR5322

The MultiBac Protein Complex Production Platform at the EMBL