Patent ID: 7364856

Claim:
A method for identifying a substance which modulates the activity of a pknB protein kinase via its interaction with a ptsp2 phosphatase, comprising contacting a recombinant bacterial cell with the substance, wherein the recombinant bacterial cell comprises one or more vectors encoding the pknB protein kinase and the pstp2 phosphatase and wherein the recombinant bacterial cell expresses the pknB protein kinase and the pstp2 phosphatase, and wherein the pknB protein kinase consists of amino acids 1 to 279 of pknB protein kinase from M. tuberculosis or an amino acid sequence having at least 95% sequence identity to amino acids 1 to 279 of pknB protein kinase from M. tuberculosis and has protein kinase activity, and the pstp2 phosphatase comprises the amino acid sequence in SEQ ID NO:1 or an amino acid sequence that is at least 95% identical to SEQ ID NO:1 and that has phosphatase activity; measuring the pknB protein kinase activity in said bacterial cell; and comparing the pknB protein kinase activity in the recombinant bacterial cell contacted with the substance to a bacterial cell which has not been contacted with the substance, wherein a change in protein kinase activity in the recombinant bacterial cell contacted with the substance relative to the pknB kinase activity in the bacterial cell which has not been contacted with the substance indicates that the substance modulates the activity of pknB protein kinase via its interaction with the pstp2 phosphatase.