A Porphyromonas gingivalis haloacid dehalogenase family phosphate interacts with human phosphoproteins and is important for invasion

Department of Oral Biology, University of Florida School of Dentistry, Gainesville, FL 32610-0424, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 08/2006; 103(29):11027-32. DOI: 10.1073/pnas.0509813103
Source: PubMed


Haloacid dehalogenase (HAD) family phosphatases are widespread in prokaryotes and are generally involved in metabolic processes. Porphyromonas gingivalis, an invasive periodontal pathogen, secretes the HAD family phosphoserine phosphatase SerB653 when in contact with gingival epithelial cells. Here we characterize the structure and enzymatic activity of SerB653 and show that a SerB653 allelic replacement mutant of P. gingivalis is deficient in internalization and persistence in gingival epithelial cells. In contrast, mutation of a second HAD family serine phosphatase of P. gingivalis (SerB1170), or of a serine transporter, did not affect invasion. A pull-down assay identified GAPDH and heat-shock protein 90 as potential substrates for SerB653. Furthermore, exogenous phosphatase regulated microtubule dynamics in host cells. These data indicate that P. gingivalis has adapted a formerly metabolic enzyme to facilitate entry into host cells by modulating host cytoskeletal architecture. Our findings define a virulence-related role of a HAD family phosphatase and reveal an invasin of an important periodontal pathogen.

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Available from: Gena D Tribble, Apr 23, 2015
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    • "As part of its strategies for survival into the host, P. gingivalis is able to invade cells and tissues (Yilmaz, 2008), thus avoiding the immune surveillance. Porphyromonas gingivalis can actively invade gingival epithelial cells, where it can maintain viability and replicate (Belton et al., 1999; Tribble et al., 2006). This invasive property is dependent on its major fimbriae, which bind to b1 integrin on the surface of host cells, an event that causes rearrangements of the actin cytoskeleton to allow internalization (Yilmaz et al., 2002, 2003). "
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