Paper Citing NAMD - Abstract
Noinaj, Nicholas; Kuszak, Adam J.; Balusek, Curtis; Gumbart, James C.; Buchanan, Susan K.
Lateral Opening and Exit Pore Formation Are Required for BamA Function
STRUCTURE, 22:1055-1062, JUL 8 2014
The outer membrane of Gram-negative bacteria is replete with a host of beta-barrel outer membrane proteins (OMPs). Despite serving a variety of essential functions, including immune response evasion, the exact mechanism of OMP folding and membrane insertion remains largely unclear. The beta-barrel assembly machinery complex is required for OMP biogenesis. Crystal structures and molecular dynamics (MD) simulations of the central and essential component, BamA, suggest a mechanism involving lateral opening of its barrel domain. MD simulations reported here reveal an additional feature of BamA: a substrate exit pore positioned above the lateral opening site. Disulfide crosslinks that prevent lateral opening and exit pore formation result in a loss of BamA function, which can be fully rescued by the reductant tris(2-carboxyethyl) phosphine. These data provide strong evidence that lateral opening and exit pore formation are required for BamA function.
