HPr kinase/phosphatase of Bacillus subtilis: expression of the gene and effects of mutations on enzyme activity, growth and carbon catabolite repression Hanson, K. G. and Steinhauer, Katrin and Reizer, Jonathan and Hillen, Wolfgang and Stülke, Jörg,, 148, 1805-1811 (2002), doi = https://doi.org/10.1099/00221287-148-6-1805, publicationName = Microbiology Society, issn = 1350-0872, abstract= HPr kinase/phosphatase (HPrK/P) is the key protein in regulation of carbon metabolism in Bacillus subtilis and many other Gram-positive bacteria. Whether this enzyme acts as a kinase or phosphatase is determined by the nutrient status of the cell. Mutational analysis of residues in a Walker A box nucleotide-binding motif revealed that it is not only important for kinase but is also involved in phosphatase activity. In addition, a signature sequence specifically conserved among HPrK/P orthologues is required for phosphatase activity and may be involved in interaction with HPr/HPr-(Ser46)-P. Carbon catabolite repression was abolished in a B. subtilis strain expressing a mutant form of HPrK/P deficient in kinase and phosphatase activities. The growth characteristics of this strain were similar to those of the wild-type. In contrast, B. subtilis strains expressing HPrK/P with partial kinase and no phosphatase activities showed growth impairment but exhibited catabolite repression., language=, type=