The Role of Heme Binding by DNA-protective Protein from Starved Cells (Dps) in the Tolerance of Porphyromonas gingivalis to Heme Toxicity
The Role of Heme Binding by DNA-protective Protein from Starved Cells (Dps) in the Tolerance of Porphyromonas gingivalis to Heme Toxicity
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DOI：
10.1074/jbc.m112.392787
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发表时间：
2012-12-07
影响因子：
4.8
通讯作者：
Ky-Anh Nguyen
中科院分区：
文献类型：
--
作者：
Gao, Jin-Long;Lu, Yanling;Ky-Anh Nguyen
The widely expressed DNA-protective protein from starved-cells (Dps) family proteins are considered major contributors to prokaryotic resistance to stress. We show here that Porphyromonas gingivalis Dps (PgDps), previously described as an iron-storage and DNA-binding protein, also mediates heme sequestration. We determined that heme binds strongly to PgDps with an apparent K-d of 3.7 x 10(-8) M and is coordinated by a single surface-located cysteine at the fifth axial ligand position. Heme and iron sequestered in separate sites by PgDps provide protection of DNA from H2O2-mediated free radical damage and were found to be important for growth of P. gingivalis under excess heme as the only iron source. Conservation of the heme-coordinating cysteine among Dps isoforms from the Bacteroidales order suggests that this function may be a common feature within these anaerobic bacteria.
