Xanthosine utilization in Salmonella enterica serovar Typhimurium is recovered by a single aspartate-to-glycine substitution in xanthosine phosphorylase.
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ABSTRACT:
SUBMITTER: Hansen MR
PROVIDER: S-EPMC1482901 | biostudies-literature | 2006 Jun
REPOSITORIES: biostudies-literature
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Xanthosine utilization in Salmonella enterica serovar Typhimurium is recovered by a single aspartate-to-glycine substitution in xanthosine phosphorylase.
Hansen Michael Riis MR Tranekjaer Jørgensen Jesper J Dandanell Gert G
Journal of bacteriology 20060601 11
xapABR from Salmonella enterica was analyzed and compared with the corresponding Escherichia coli genes. xapB and xapR, but not xapA, encode functional proteins. An S. enterica XapA(Asp72Gly) mutant that restores the phosphorolytic activity was selected. The purified mutant enzyme has different kinetic constants than the E. coli enzyme but similar substrate specificity. ...[more]
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