ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

The Escherichia coli Phosphotyrosine Proteome Relates to Core Pathways and Virulence

Hansen, Anne-Marie and Chaerkady, Raghothama and Sharma, Jyoti and Diaz-Mejia, Javier J and Tyagi, Nidhi and Renuse, Santosh and Jacob, Harrys KC and Pinto, Sneha M and Sahasrabuddhe, Nandini A and Kim, Min-Sik and Delanghe, Bernard and Srinivasan, Narayanaswamy and Emili, Andrew and Kaper, James B and Pandey, Akhilesh (2013) The Escherichia coli Phosphotyrosine Proteome Relates to Core Pathways and Virulence. In: PLOS PATHOGENS, 9 (6).

[img]
Preview
PDF
journal.ppat.1003403.pdf - Published Version
Available under License Creative Commons Attribution.

Download (3MB) | Preview
Official URL: http://dx.doi.org/10.1371/journal.ppat.1003403

Abstract

While phosphotyrosine modification is an established regulatory mechanism in eukaryotes, it is less well characterized in bacteria due to low prevalence. To gain insight into the extent and biological importance of tyrosine phosphorylation in Escherichia coli, we used immunoaffinity-based phosphotyrosine peptide enrichment combined with high resolution mass spectrometry analysis to comprehensively identify tyrosine phosphorylated proteins and accurately map phosphotyrosine sites. We identified a total of 512 unique phosphotyrosine sites on 342 proteins in E. coli K12 and the human pathogen enterohemorrhagic E. coli (EHEC) O157:H7, representing the largest phosphotyrosine proteome reported to date in bacteria. This large number of tyrosine phosphorylation sites allowed us to define five phosphotyrosine site motifs. Tyrosine phosphorylated proteins belong to various functional classes such as metabolism, gene expression and virulence. We demonstrate for the first time that proteins of a type III secretion system (T3SS), required for the attaching and effacing (A/E) lesion phenotype characteristic for intestinal colonization by certain EHEC strains, are tyrosine phosphorylated by bacterial kinases. Yet, A/E lesion and metabolic phenotypes were unaffected by the mutation of the two currently known tyrosine kinases, Etk and Wzc. Substantial residual tyrosine phosphorylation present in an etk wzc double mutant strongly indicated the presence of hitherto unknown tyrosine kinases in E. coli. We assess the functional importance of tyrosine phosphorylation and demonstrate that the phosphorylated tyrosine residue of the regulator SspA positively affects expression and secretion of T3SS proteins and formation of A/E lesions. Altogether, our study reveals that tyrosine phosphorylation in bacteria is more prevalent than previously recognized, and suggests the involvement of phosphotyrosine-mediated signaling in a broad range of cellular functions and virulence.

Item Type: Journal Article
Additional Information: Copyright of this article is belongs to the authors
Department/Centre: Division of Biological Sciences > Molecular Biophysics Unit
Depositing User: Id for Latest eprints
Date Deposited: 06 Sep 2013 07:36
Last Modified: 05 Mar 2019 09:24
URI: http://eprints.iisc.ac.in/id/eprint/47072

Actions (login required)

View Item View Item