title: Identification of Ser/Thr kinase and forkhead associated domains in Mycobacterium ulcerans: characterization of novel association between protein kinase Q and MupFHA.
abstract: BACKGROUND
  Mycobacterium ulcerans, the causative agent of Buruli ulcer in humans, is unique among the members of Mycobacterium genus due to the presence of the virulence determinant megaplasmid pMUM001. This plasmid encodes multiple virulence-associated genes, including mup011, which is an uncharacterized Ser/Thr protein kinase (STPK) PknQ.
  
  
  RESULTS
  In this study, we have characterized PknQ and explored its interaction with MupFHA (Mup018c), a FHA domain containing protein also encoded by pMUM001. MupFHA was found to interact with PknQ and suppress its autophosphorylation. Subsequent protein-protein docking and molecular dynamic simulation analyses showed that this interaction involves the FHA domain of MupFHA and PknQ activation loop residues Ser170 and Thr174. FHA domains are known to recognize phosphothreonine residues, and therefore, MupFHA may be acting as one of the few unusual FHA-domain having overlapping specificity. Additionally, we elucidated the PknQ-dependent regulation of MupDivIVA (Mup012c), which is a DivIVA domain containing protein encoded by pMUM001. MupDivIVA interacts with MupFHA and this interaction may also involve phospho-threonine/serine residues of MupDivIVA.
  
  
  CONCLUSIONS
  Together, these results describe novel signaling mechanisms in M. ulcerans and show a three-way regulation of PknQ, MupFHA, and MupDivIVA. FHA domains have been considered to be only pThr specific and our results indicate a novel mechanism of pSer as well as pThr interaction exhibited by MupFHA. These results signify the need of further re-evaluating the FHA domain -pThr/pSer interaction model. MupFHA may serve as the ideal candidate for structural studies on this unique class of modular enzymes.
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India; Translational Health Science and Technology Institute, Gurgaon, India.
authors.forename: Gunjan
authors.initials: G
authors.lastname: Arora
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Andaleeb
authors.initials: A
authors.lastname: Sajid
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Anshika
authors.initials: A
authors.lastname: Singhal
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Jayadev
authors.initials: J
authors.lastname: Joshi
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Richa
authors.initials: R
authors.lastname: Virmani
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Meetu
authors.initials: M
authors.lastname: Gupta
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Nupur
authors.initials: N
authors.lastname: Verma
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Abhijit
authors.initials: A
authors.lastname: Maji
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Richa
authors.initials: R
authors.lastname: Misra
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS, UMR 5235, Place Eugène Bataillon, Montpellier, France.
authors.forename: Grégory
authors.initials: G
authors.lastname: Baronian
authors.affiliation: Translational Health Science and Technology Institute, Gurgaon, India.
authors.forename: Amit K
authors.initials: AK
authors.lastname: Pandey
authors.affiliation: Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS, UMR 5235, Place Eugène Bataillon, Montpellier, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Molle
authors.affiliation: CSIR- Institute of Genomics and Integrative Biology, Delhi, India.
authors.forename: Yogendra
authors.initials: Y
authors.lastname: Singh
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D019295:Computational Biology; D051858:Forkhead Transcription Factors / Q000737:chemistry* / Q000378:metabolism; D056004:Molecular Dynamics Simulation; D019911:Mycobacterium ulcerans / Q000737:chemistry* / Q000201:enzymology / Q000378:metabolism; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary
chemical_list: D001426:Bacterial Proteins; D051858:Forkhead Transcription Factors; D017346:Protein Serine-Threonine Kinases