6izt
Crystal structure of Haemophilus Influenzae BamA POTRA3-5Crystal structure of Haemophilus Influenzae BamA POTRA3-5
Structural highlights
FunctionBAMA1_HAEIF Part of the outer membrane protein assembly complex, which is involved in assembly and insertion of beta-barrel proteins into the outer membrane.[HAMAP-Rule:MF_01430] Publication Abstract from PubMedAlmost all the outer membrane proteins (OMPs) fold into an invariant beta-barrel fold via the polypeptide-transport-associated (POTRA) motif and beta-barrel assembly machinery (BAM). However, whether and how poly-POTRAs interact with OMPs remain largely unknown. Here, we have characterized the structures of Haemophilus influenzae poly-POTRAs via X-ray crystallography, small angle X-ray scattering, and molecular dynamics simulation. Unexpectedly, crystal packing reveals a putative OMP travel pathway spiraled by the conserved alpha2-beta2 edges in poly-POTRAs. Supportively, the structure-based mutations targeting the OMP binding sites significantly disrupt OMP biogenesis, resulting in severe cell growth defects. Another notable feature in H. influenzae POTRA structures is flexibility. As characterized by ELISA assays, poly-POTRAs could recruit OMP substrates in a step-wise manner. More importantly, the restriction of POTRA-POTRA linkage and flexibility significantly impairs the BamA function and causes cell growth defect. Altogether, these results suggest that the beta-strand augmentations and intrinsic flexibility are important factors for BamA-OMP recruitment.-Ma, X., Wang, Q., Li, Y., Tan, P., Wu, H., Wang, P., Dong, X., Hong, L., Meng, G. How BamA recruits OMP substrates via poly-POTRAs domain. How BamA recruits OMP substrates via poly-POTRAs domain.,Ma X, Wang Q, Li Y, Tan P, Wu H, Wang P, Dong X, Hong L, Meng G FASEB J. 2019 Nov 8:fj201900681RR. doi: 10.1096/fj.201900681RR. PMID:31702961[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|