title: The phosphothreonine lyase activity of a bacterial type III effector family.
abstract: Pathogenic bacteria use the type III secretion system to deliver effector proteins into host cells to modulate the host signaling pathways. In this study, the Shigella type III effector OspF was shown to inactivate mitogen-activated protein kinases (MAPKs) [extracellular signal-regulated kinases 1 and 2 (Erk1/2), c-Jun N-terminal kinase, and p38]. OspF irreversibly removed phosphate groups from the phosphothreonine but not from the phosphotyrosine residue in the activation loop of MAPKs. Mass spectrometry revealed a mass loss of 98 daltons in p-Erk2, due to the abstraction of the alpha proton concomitant with cleavage of the C-OP bond in the phosphothreonine residue. This unexpected enzymatic activity, termed phosphothreonine lyase, appeared specific for MAPKs and was shared by other OspF family members.
authors.affiliation: National Institute of Biological Sciences, Beijing, 102206, China.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Li
authors.forename: Hao
authors.initials: H
authors.lastname: Xu
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Chengzu
authors.initials: C
authors.lastname: Long
authors.forename: Shuqin
authors.initials: S
authors.lastname: Li
authors.forename: She
authors.initials: S
authors.lastname: Chen
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Zhou
authors.forename: Feng
authors.initials: F
authors.lastname: Shao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006367:HeLa Cells; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016328:NF-kappa B / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D012486:Salmonella typhimurium; D012763:Shigella flexneri / Q000378:metabolism* / Q000502:physiology; D014443:Tyrosine / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D016328:NF-kappa B; D014443:Tyrosine; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D010749:Phosphoprotein Phosphatases