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Volume 3, Issue 2
ISSN: 2470-9905
Crystallography 2017
October 16-17, 2017
2
nd
International Conference on
October 16-17, 2017 | Chicago, USA
Applied Crystallography
Crystal structures of a polypeptide processing and secretion transporter
David Lin
Iowa State University, USA
B
acteria secrete peptides and proteins to communicate, to poison competitors, and to manipulate host cells. In Gram-positive
bacteria, peptidase-containing ABC transporters (PCATs) function both as maturation proteases and as exporters for quorum-
sensing or antimicrobial polypeptides. In Gram-negative bacteria, PCATs interact with two other membrane proteins to form the
type 1 secretion system. We showed here the first crystal structures of PCAT1 from
Clostridium thermocellum
in two different
conformations. These structures, accompanied by biochemical data, show that the translocation pathway is a large α-helical barrel
sufficient to accommodate small folded proteins. ATP binding alternates access to the transmembrane pathway and regulates the
protease activity, thereby coupling substrate processing to translocation.
dylin@iastate.eduStruct Chem Crystallogr Commun, 3:2
DOI: 10.21767/2470-9905-C1-003