Secretins form megadalton bacterial-membrane channels in at least four sophisticated multiprotein systems that are crucial for translocation of proteins and assembled fibers across the outer membrane of many species of bacteria. Secretin subunits contain multiple domains, which interact with numerous other proteins, including pilotins, secretion-system partner proteins, and exoproteins. Our understanding of the structure of secretins is rapidly progressing, and it is now recognized that features common to all secretins include a cylindrical arrangement of 12-15 subunits, a large periplasmic vestibule with a wide opening at one end and a periplasmic gate at the other. Secretins might also play a key role in the biogenesis of their cognate secretion systems.
|Number of pages||11|
|Journal||Trends in Biochemical Sciences|
|State||Published - Aug 2011|
Bibliographical noteFunding Information:
We thank Stewart Turley, Steve Reichow, Jan Steyaert and Els Pardon for contributions to the studies on the T2SS secretin in our laboratories, Ariel Blocker for discussion of unpublished data, and Maria Sandkvist for stimulating discussions of secretion mechanism. This work was supported by award RO1AI34501 (to W.G.J.H) from the National Institute of Allergy and Infectious Diseases. We thank the Murdock Charitable Trust and the Washington Research Foundation for generous support of our cryo-EM laboratory. T.G. is a Howard Hughes Medical Institute Early Career Scientist.
ASJC Scopus subject areas
- Molecular Biology