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Publication Abstract from PubMed

Ser/Thr phosphorylation has emerged as a critical regulatory mechanism in a number of bacteria, including Mycobacterium tuberculosis. This problematic pathogen encodes 11 eukaryotic-like Ser/Thr kinases, yet few substrates or signaling targets have been characterized. Here, we report the structure of EmbR (2.0 A), a putative transcriptional regulator of key arabinosyltransferases (EmbC, -A, and -B), and an endogenous substrate of the Ser/Thr-kinase PknH. EmbR presents a unique domain architecture: the N-terminal winged-helix DNA-binding domain forms an extensive interface with the all-helical central bacterial transcriptional activation domain and is positioned adjacent to the regulatory C-terminal forkhead-associated (FHA) domain, which mediates binding to a Thr-phosphorylated site in PknH. The structure in complex with a phospho-peptide (1.9 A) reveals a conserved mode of phospho-threonine recognition by the FHA domain and evidence for specific recognition of the cognate kinase. The present structures suggest hypotheses as to how EmbR might propagate the phospho-relay signal from its cognate kinase, while serving as a template for the structurally uncharacterized Streptomyces antibiotic regulatory protein family of transcription factors.

Molecular structure of EmbR, a response element of Ser/Thr kinase signaling in Mycobacterium tuberculosis.,Alderwick LJ, Molle V, Kremer L, Cozzone AJ, Dafforn TR, Besra GS, Futterer K Proc Natl Acad Sci U S A. 2006 Feb 21;103(8):2558-63. Epub 2006 Feb 13. PMID:16477027^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.