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bioRxiv · 10.1101/2023.11.16.567405

Homologs of the plastidal preprotein translocase Tic20 mediate organelle assembly in bacteria

Paulus, A.·Ahrens, F.·Schraut, A.·Hofman, H.·Schiller, T.·Sura, T.·Becher, D.·Uebe, R.
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Abstract

Organelle-specific protein translocation systems are essential for organelle biogenesis and maintenance in eukaryotes but thought to be absent from prokaryotic organelles. Here, we identified that MamF-like proteins involved in the formation of bacterial magnetosome organelles share an ancient origin with Tic20 protein translocases found in chloroplasts. Deletion of mamF-like genes in the alphaproteobacterium Magnetospirillum gryphiswaldense results in severe defects in organelle positioning, biomineralization, and magnetic navigation. Consistent with translocase-like functions, these defects are caused by the loss of magnetosome targeting of a subset of organellar proteins containing C-terminal glycine-rich integral membrane domains. Our findings suggest that organelle-specific protein translocation systems may indeed play a role in bacterial organelle formation.

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Paulus, A., Ahrens, F., Schraut, A., Hofman, H., Schiller, T., Sura, T., Becher, D., Uebe, R.. 2023-11-16. Homologs of the plastidal preprotein translocase Tic20 mediate organelle assembly in bacteria. https://doi.org/10.1101/2023.11.16.567405

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