English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Outer membrane β-barrels (OMBBs) are toroidal arrays of antiparallel β-strands that span the outer membrane of Gram-negative bacteria and eukaryotic organelles. Although homologous, most families of bacterial OMBBs evolved through the independent amplification of an ancestral ββ-hairpin. In mitochondria, one family (SAM50) has a clear bacterial ancestry; the origin of the other family, consisting of 19-stranded OMBBs found only in mitochondria (MOMBBs), is substantially unclear. In a large-scale comparison of mitochondrial and bacterial OMBBs, we find evidence that the common ancestor of all MOMBBs emerged by the amplification of a double ββ-hairpin of bacterial origin, probably at the time of the Last Eukaryotic Common Ancestor. Thus, MOMBBs are indeed descended from bacterial OMBBs, but their fold formed independently in the proto-mitochondria, possibly in response to the need for a general-purpose polypeptide importer. This occurred by a process of amplification, despite the final fold having a prime number of strands.

The Origin of Mitochondria-Specific Outer Membrane β-Barrels from an Ancestral Bacterial Fragment