The structures of BtuCD and MscS and their implications for transporter and channel function.
The passage of most molecules across biological membranes is mediated by specialized integral membrane proteins known as channels and transporters. Although these transport families encompass a wide range of functions, molecular architectures and mechanisms, there are common elements that must be incorporated within their structures, namely the translocation pathway, ligand specificity elements and regulatory sensors to control the rate of ligand flow across the membrane. This minireview discusses aspects of the structure and mechanism of two bacterial transport systems, the stretch-activated mechanosensitive channel of small conductance (MscS) and the ATP-dependent vitamin B12 uptake system (BtuCD), emphasizing their general implications for transporter function.
Bass
Randal B
RB
Division of Chemistry and Chemical Engineering, 114-96, California Institute of Technology, Pasadena, CA 91125, USA.
Locher
Kaspar P
KP
Borths
Elizabeth
E
Poon
Yan
Y
Strop
Pavel
P
Lee
Allen
A
Rees
Douglas C
DC
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism*; D015640:Ion Channel Gating; D007473:Ion Channels / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D011487:Protein Conformation; D014805:Vitamin B 12 / Q000378:metabolism
D018528:ATP-Binding Cassette Transporters; C050021:BtuC peptide, E coli; C050022:BtuD peptide, E coli; D029968:Escherichia coli Proteins; D007473:Ion Channels; C469542:MscS protein, E coli; D014805:Vitamin B 12