Serine 83 in DosR, a response regulator from Mycobacterium tuberculosis, promotes its transition from an activated, phosphorylated state to an inactive, unphosphorylated state.
A sensor kinase, DosS, and its corresponding response regulator, DosR, constitute a two component system for regulating gene expression under hypoxic conditions in Mycobacterium tuberculosis. Among response regulators in M. tuberculosis, NarL has high sequence similarity to DosR, and autophosphorylated DosS transfers its phosphate group not only to DosR but also to NarL. Phosphorylated DosR is more rapidly dephosphorylated than phosphorylated NarL. DosR and NarL differ with respect to the amino acids at positions T+1 and T+2 around the phosphorylation sites in the N-terminal phosphoacceptor domain; NarL has S83 and Y84, whereas DosR has A90 and H91. A DosR S83A mutant shows prolonged phosphorylation. Structural comparison with a histidinol phosphate phosphatase suggests that the hydroxyl group of DosR S83 could play a role in activating the water molecule involved in the triggering of autodephosphorylation.
School of Life Sciences and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea.
Ha Yeon
HY
Cho
School of Life Sciences and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address: bskang2@knu.ac.kr.
Beom Sik
BS
Kang
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D008958:Models, Molecular; D009169:Mycobacterium tuberculosis / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010766:Phosphorylation; D017354:Point Mutation; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012694:Serine / Q000235:genetics / Q000378:metabolism; D014376:Tuberculosis / Q000382:microbiology*
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C542863:DosR protein, Mycobacterium tuberculosis; D012694:Serine; D011494:Protein Kinases
Autodephosphorylation; DosR; DosS; Mycobacterium tuberculosis; Response regulator; Sensor kinase