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A new structural class of bacterial thioester domains reveals a slipknot topology.

ABSTRACT: An increasing number of surface-associated proteins identified in Gram-positive bacteria are characterized by intramolecular cross-links in structurally conserved thioester, isopeptide, and ester domains (TIE proteins). Two classes of thioester domains (TEDs) have been predicted based on sequence with, to date, only representatives of Class I structurally characterized. Here, we present crystal structures of three Class II TEDs from Bacillus anthracis, vancomycin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus faecium. These proteins are structurally distinct from Class I TEDs due to a ?-sandwich domain that is inserted into the conserved TED fold to form a slipknot structure. Further, the B. anthracis TED domain is presented in the context of a full-length sortase-anchored protein structure (BaTIE). This provides insight into the three-dimensional arrangement of TIE proteins, which emerge as very abundant putative adhesins of Gram-positive bacteria.

SUBMITTER: Miller OK

PROVIDER: S-EPMC6194298 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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A new structural class of bacterial thioester domains reveals a slipknot topology.

Miller Ona K OK Banfield Mark J MJ Schwarz-Linek Ulrich U

Protein science : a publication of the Protein Society 20180925 9

An increasing number of surface-associated proteins identified in Gram-positive bacteria are characterized by intramolecular cross-links in structurally conserved thioester, isopeptide, and ester domains (TIE proteins). Two classes of thioester domains (TEDs) have been predicted based on sequence with, to date, only representatives of Class I structurally characterized. Here, we present crystal structures of three Class II TEDs from Bacillus anthracis, vancomycin-resistant Staphylococcus aureus, ...[more]

PMID: 30052296

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Dataset Information

A new structural class of bacterial thioester domains reveals a slipknot topology.

Publications

A new structural class of bacterial thioester domains reveals a slipknot topology.

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