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Surface protein IsdC and Sortase B are required for heme-iron scavenging of Bacillus anthracis.

ABSTRACT: Bacillus anthracis, the spore-forming agent of anthrax, requires iron for growth and is capable of scavenging heme-iron during infection. We show here that the B. anthracis iron-regulated surface determinants (isd) locus encompasses isdC, specifying a heme-iron binding surface protein. Anchoring of IsdC to the cell wall envelopes of vegetative bacilli requires srtB, which encodes sortase B. Purified sortase B cleaves IsdC between the threonine and the glycine of its NPKTG motif sorting signal. B. anthracis variants lacking either isdC or srtB display defects in heme-iron scavenging, suggesting that IsdC binding to heme-iron in the cell wall envelope contributes to bacterial uptake of heme.

SUBMITTER: Maresso AW

PROVIDER: S-EPMC1698196 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Surface protein IsdC and Sortase B are required for heme-iron scavenging of Bacillus anthracis.

Maresso Anthony W AW Chapa Travis J TJ Schneewind Olaf O

Journal of bacteriology 20060929 23

Bacillus anthracis, the spore-forming agent of anthrax, requires iron for growth and is capable of scavenging heme-iron during infection. We show here that the B. anthracis iron-regulated surface determinants (isd) locus encompasses isdC, specifying a heme-iron binding surface protein. Anchoring of IsdC to the cell wall envelopes of vegetative bacilli requires srtB, which encodes sortase B. Purified sortase B cleaves IsdC between the threonine and the glycine of its NPKTG motif sorting signal. B ...[more]

PMID: 17012401

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