Topography of the interaction of HPr(Ser) kinase with HPr

Research was conducted to identify the specificity requirements for phosphorylation of Mycoplasma capricolum HPr. A mutagenesis method was used in which residues 43-57 in a chimera were replaced by the Escherichia coli sequence. Results indicate that the kinase-HPr interaction takes place mostly through a hydrophobic region. Comparisons conducted between the chimeric construct and M. capricolum provide a basis for the interpretation of activity assays results.