The Staphylococcus aureus secretome - TI Pharma

Characterization of Staphylococcus aureus secretion mutants
Table 1 Relevant components of S. aureus secretion pathways a
Protein Essential b
Sec-pathway
Chaperone Ffh Y n.a.
FtsY Y n.a.
Translocation motor SecA1
Y
n.a.
SecA2
N
N
Translocation channel SecY1
Y
n.a.
SecY2
N
Y
SecE Y n.a.
SecG N Y
SecDF Y N
YrbF ? n.a.
Membrane insertase SpoIIIJ/YqjG Y N
Lipid modification Lgt N Y
Signal peptidase SpsA (inactive)
N
SpsB
Y c
Y
N
LspA N Y
Folding catalyst PrsA N Y
DsbA N Y
Cell wall attachment SrtA N Y
SrtB N Y
Tat-pathway
Pseudopilin pathway
Holins
Ess
TatA
TatC
ComGA
N
Y
ComGC
N
Y
ComC N Y
CidA N Y
LrgA N Y
EsaA
EssA
EssB
EssC
75
N
N
Deletion Mutant
a Table adapted from Sibbald et al. (2006); b Chaudhuri et al. (2009); c Cregg et al. (1996); for proteins marked
“n.a.” we did not attempt to delete the corresponding genes, because they were known to be essential (ffh,
ftsY, secA1, secY1, secE), or of seemingly minor relevance (yrbF).
Material & Methods
Bacterial strains and growth
Strains and plasmids used in this study are listed in Table 2. E. coli and S. aureus strains were grown at
37°C under aerobic conditions. E. coli strains were grown in Luria-Bertani broth (LB). Unless stated
otherwise, S. aureus strains were grown at 37°C in tryptic soy broth (TSB) under vigorous shaking or
on trypic soy agar (TSA) plates. Antibiotics for E. coli strains were added in the following final
concentrations: ampicillin 100 µg/ml, kanamycin 20 µg/ml, and erythromycin 100 µg/ml. For S. aureus
the following final concentrations were used: kanamycin 20 µg/ml, and erythromycin 5 µg/ml. To
monitor β-galactosidase activity in S. aureus, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (Xgal)
was added to the plates at a final concentration of 80 µg/ml.
N
N
N
N
Y
Y
N
N
N
N