3ori
From Proteopedia
Mycobacterium tuberculosis PknB kinase domain L33D mutant (crystal form 1)
Structural highlights
FunctionPKNB_MYCTU Key component of a signal transduction pathway that regulates cell growth and cell division via phosphorylation of target proteins such as GarA, GlmU, PapA5, PbpA, FhaB (Rv0019c), FhaA (Rv0020c), MviN, PstP, EmbR, Rv1422, Rv1747 and RseA. Shows a strong preference for Thr versus Ser as the phosphoacceptor.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] Publication Abstract from PubMedThe essential Mycobacterium tuberculosis Ser/Thr protein kinase (STPK), PknB, plays a key role in regulating growth and division, but the structural basis of activation has not been defined. Here, we provide biochemical and structural evidence that dimerization through the kinase-domain (KD) N-lobe activates PknB by an allosteric mechanism. Promoting KD pairing using a small-molecule dimerizer stimulates the unphosphorylated kinase, and substitutions that disrupt N-lobe pairing decrease phosphorylation activity in vitro and in vivo. Multiple crystal structures of two monomeric PknB KD mutants in complex with nucleotide reveal diverse inactive conformations that contain large active-site distortions that propagate > 30 A from the mutation site. These results define flexible, inactive structures of a monomeric bacterial receptor KD and show how "back-to-back" N-lobe dimerization stabilizes the active KD conformation. This general mechanism of bacterial receptor STPK activation affords insights into the regulation of homologous eukaryotic kinases that form structurally similar dimers. Allosteric activation mechanism of the Mycobacterium tuberculosis receptor Ser/Thr protein kinase, PknB.,Lombana TN, Echols N, Good MC, Thomsen ND, Ng HL, Greenstein AE, Falick AM, King DS, Alber T Structure. 2010 Dec 8;18(12):1667-77. doi: 10.1016/j.str.2010.09.019. PMID:21134645[12] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations No citations found See AlsoReferences
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