Dataset Information

Phosphoproteomic analysis of Staphylococcus aureus

ABSTRACT: S. aureus is one of the major human pathogens that greatly impacts individuals and causes a variety of illnesses ranging from minor skin infections to life-threatening diseases, such as endocarditis, pneumonia, septicemia and toxic shock syndrome. Stk1/Stp1 are particular important for S. aureus pathogenesis and survival as they are thought to participate in regulating virulence, cell wall structure and antibiotic resistance. Understanding how Ser/Thr phosphorylation regulates virulence and antibiotic resistance will provide foundation for the development of novel therapeutic strategies against S. aureus infection. The phosphoproteomic analysis of Staphylococcus aureus Newman strain led to the identification of 76 peptides with mapped phosphorylation sites belonging to 29 distinct proteins. In the case of Stk1, only one peptide (residues 157-182), with the sequence ALSETSLTQTNHVLGTVQYFSPEQAK, was predicted to have a cluster of six phosphorylation sites (Ser159, Thr161, Ser162, Thr164, Thr166 and Thr172). This segment overlaps with the sequence of kinase activation loop (residues 154-176) in Stk1. Further biochemical studies revealed cis autophosphorylation of Thr172 in the GT/S motif is necessary for self-activation and kinase activity of Stk1, whereas the trans autophosphorylation of other activation loop serines/threonins are essential for the optimal kinase activity of Stk1.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Staphylococcus Aureus

SUBMITTER: Weihao Zheng

LAB HEAD: Zigang Li

PROVIDER: PXD006285 | Pride | 2018-10-24

REPOSITORIES: Pride

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Publications

Autophosphorylation Mechanism of the Ser/Thr Kinase Stk1 From Staphylococcus aureus.

Zheng Weihao W Cai Xiaodan X Li Shuiming S Li Zigang Z

Frontiers in microbiology 20180420

The eukaryotic-like Ser/Thr kinase Stk1 is crucial for virulence, cell wall biosynthesis, and drug susceptibility in methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA). Importantly, MRSA lacking Stk1 become sensitive to β-lactam antibiotics, implying that Stk1 could be an alternative target for combination therapy. However, the autophosphorylation mechanism of Stk1 remains elusive. Using a phosphoproteomic study, we identified six in vivo phosphorylated activatio ...[more]

PMID: 29731745

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Dataset Information

Phosphoproteomic analysis of Staphylococcus aureus

Publications

Autophosphorylation Mechanism of the Ser/Thr Kinase Stk1 From <i>Staphylococcus aureus</i>.

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