Publication Date:
2015-07-24
Description:
Bacteria secrete peptides and proteins to communicate, to poison competitors, and to manipulate host cells. Among the various protein-translocation machineries, the peptidase-containing ATP-binding cassette transporters (PCATs) are appealingly simple. Each PCAT contains two peptidase domains that cleave the secretion signal from the substrate, two transmembrane domains that form a translocation pathway, and two nucleotide-binding domains that hydrolyse ATP. In Gram-positive bacteria, PCATs function both as maturation proteases and 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. Here we present 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 alpha-helical barrel sufficient to accommodate small folded proteins. ATP binding alternates access to the transmembrane pathway and also regulates the protease activity, thereby coupling substrate processing to translocation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lin, David Yin-wei -- Huang, Shuo -- Chen, Jue -- Howard Hughes Medical Institute/ -- England -- Nature. 2015 Jul 23;523(7561):425-30. doi: 10.1038/nature14623.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Laboratory of Membrane Biology and Biophysics, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA [2] Howard Hughes Medical Institute, 1230 York Avenue, New York, New York 10065, USA. ; Howard Hughes Medical Institute, 1230 York Avenue, New York, New York 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26201595" target="_blank"〉PubMed〈/a〉
Keywords:
ATP-Binding Cassette Transporters/*chemistry/metabolism
;
Adenosine Triphosphate/deficiency/metabolism
;
Clostridium thermocellum/*chemistry
;
Crystallography, X-Ray
;
Models, Molecular
;
Peptides/*metabolism/secretion
;
Protein Binding
;
Protein Multimerization
;
Protein Structure, Tertiary
;
Structure-Activity Relationship
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
