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Fitting the Pieces of the ?-Barrel Assembly Machinery Complex.

ABSTRACT: ?-Barrel membrane proteins are found in the outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria; however, exactly how they are folded and inserted remains unknown. Over the past decade, both functional and structural studies have greatly contributed to addressing this elusive mechanism. It is known that a conserved core machinery is required for each organelle, though the overall composition varies significantly. The vast majority of studies that aimed to understand the biogenesis of ?-barrel membrane proteins has been conducted in Gram-negative bacteria. Here, it is the task of a multicomponent complex known as the ?-barrel assembly machinery (BAM) complex to fold and insert new ?-barrel membrane proteins into the outer membrane. In this review, we will discuss recent discoveries with the goal of utilizing all reported structural and functional studies to piece together a current structural model for the fully assembled BAM complex.

SUBMITTER: O'Neil PK

PROVIDER: S-EPMC4631317 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Fitting the Pieces of the β-Barrel Assembly Machinery Complex.

O'Neil Patrick K PK Rollauer Sarah E SE Noinaj Nicholas N Buchanan Susan K SK

Biochemistry 20151006 41

β-Barrel membrane proteins are found in the outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria; however, exactly how they are folded and inserted remains unknown. Over the past decade, both functional and structural studies have greatly contributed to addressing this elusive mechanism. It is known that a conserved core machinery is required for each organelle, though the overall composition varies significantly. The vast majority of studies that aimed to understand the bio ...[more]

PMID: 26394220

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