A Modular BAM Complex in the Outer Membrane of the alpha-Proteobacterium Caulobacter crescentus

作者:Anwari Khatira*; Poggio Sebastian; Perry Andrew; Gatsos Xenia; Ramarathinam Sri Harsha; Williamson Nicholas A; Noinaj Nicholas; Buchanan Susan; Gabriel Kipros; Purcell Anthony W; Jacobs Wagner Christine; Lithgow Trevor
来源:PLos One, 2010, 5(1): e8619.
DOI:10.1371/journal.pone.0008619

摘要

Mitochondria are organelles derived from an intracellular alpha-proteobacterium. The biogenesis of mitochondria relies on the assembly of beta-barrel proteins into the mitochondrial outer membrane, a process inherited from the bacterial ancestor. Caulobacter crescentus is an alpha-proteobacterium, and the BAM (beta-barrel assembly machinery) complex was purified and characterized from this model organism. Like the mitochondrial sorting and assembly machinery complex, we find the BAM complex to be modular in nature. A similar to 150 kDa core BAM complex containing BamA, BamB, BamD, and BamE associates with additional modules in the outer membrane. One of these modules, Pal, is a lipoprotein that provides a means for anchorage to the peptidoglycan layer of the cell wall. We suggest the modular design of the BAM complex facilitates access to substrates from the protein translocase in the inner membrane.

  • 出版日期2010-1-8