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Published on: August 19, 2016
HtrA protease and processing of extracellular proteins of Streptococcus mutans
1Oral Biology, Dental School, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4BW, UK.
Abstract:
A homologue of the HtrA family of stress-response proteases was detected by analysis of the Streptococcus mutans genome sequence. Disabling of the S. mutans htrA gene by insertional inactivation resulted in bacterial clumping in liquid medium, altered colony morphology and a reduced ability to withstand high temperature, extremes of pH or oxidative stress. Seven different extracellular or wall-associated proteins that are known to be subject to post-translational proteolysis were examined in cultures of wild-type S. mutans and an htrA mutant. Inactivation of the htrA protease had no effect on degradation of the proteins.
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