Quantitative cell surface proteome profiling for SigB-dependent protein expression in the human pathogen Staphylococcus aureus via biotinylation approach.
Most of the Staphylococcus aureus virulence factors are either cell surface exposed or secreted. Here we report a global and quantitative analysis of staphylococcal cell surface-associated proteins using a combination of (14)N(15)N metabolic labeling, biotinylation, and GeLC-MS/MS. To address the important question of S. aureus pathophysiology, we analyzed the influence of the alternative sigma factor sigma(B) on the expression of cell surface-associated proteins. Therefore, we compared the methicillin-resistant S. aureus wild-type strain COL with its sigB mutant, because sigma(B) might play a crucial role in the pattern of the surface proteome. A total of 296 proteins from growing and nongrowing cells could be quantified. One third of these proteins are known as cell surface-associated, including 3 sortase substrates, 3 cell wall-associated proteins, 35 lipo-, 23 membrane-, and 34 signal peptide-containing proteins comparing wild-type and sigB mutant. Fourty nine surface-associated proteins were modulated by sigma(B), including 21 proteins already known to be SigB-dependent or SigB-influenced. More proteins were down- (31 proteins) than up-regulated (18 proteins) in the sigB mutant. Our approach revealed 28 surface-associated proteins not previously reported as SigB-dependent or -influenced, expanding the group of surface-associated proteins and virulence factors modulated by SigB.
Hempel
Kristina
K
Institute for Microbiology, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany.
Pané-Farré
Jan
J
Otto
Andreas
A
Sievers
Susanne
S
Hecker
Michael
M
Becher
Dörte
D
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001710:Biotin / Q000378:metabolism; D007553:Isotope Labeling; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008954:Models, Biological; D009154:Mutation; D009587:Nitrogen Isotopes / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013211:Staphylococcus aureus / Q000737:chemistry / Q000378:metabolism*
D001426:Bacterial Proteins; D008565:Membrane Proteins; D009587:Nitrogen Isotopes; C079011:SigB protein, Bacteria; D012808:Sigma Factor; D001710:Biotin