Many Families of Lids for TonB-dependent Transporters in Bacteroides

Price, M. N.; Deutschbauer, A. N.; Arkin, A. P.

doi:10.1101/2023.03.17.533168

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bioRxiv · 10.1101/2023.03.17.533168

Many Families of Lids for TonB-dependent Transporters in Bacteroides

Price, M. N.·Deutschbauer, A. N.·Arkin, A. P.

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Abstract

Most TonB-dependent transporters in Bacteroides belong to the SusC family and work with an outer-membrane lipoprotein from the SusD family that functions like a lid. But the best-studied strain, B. thetaiotaomicron VPI-5482, also contains 18 TonB-dependent transporters that are not from the SusC family. We identified six families of putative lids for these transporters. The putative lids are lipoproteins that are encoded next to TonB-dependent transporters, but they are not homologous to SusD. AlphaFold-Multimer predicts that the putative lids bind the outer faces of the corresponding TonB-dependent receptors. Genetic data suggests that members of four of these families are required for the activity of the corresponding TonB-dependent receptors. Overall, of the 18 TonB-dependent receptors that do not belong to the SusC family, we identified alternate lids for nine.

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Price, M. N., Deutschbauer, A. N., Arkin, A. P.. 2023-03-18. Many Families of Lids for TonB-dependent Transporters in Bacteroides. https://doi.org/10.1101/2023.03.17.533168

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