Affiliation:
1. Departments of Medicine1 and
2. Pathology,2 Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
Abstract
ABSTRACT
The effect of O
2
and CO
2
on expression of toxic shock syndrome toxin 1 (TSST-1) by
Staphylococcus aureus
was investigated under controlled growth conditions with continuous-culture techniques. To stimulate TSST-1 production, air and anaerobic gas were premixed before delivery to the culture vessel. At a growth rate—or mass doubling time (
t
d
)—of 3 h, production of specific TSST-1 (expressed as micrograms per milligram of cell dry weight) was 5.9-fold greater at an O
2
concentration of 4% than under anaerobic conditions. Increasing the O
2
concentration to 11% did not result in a significant increase (
P
> 0.05) in the rate of toxin production over that during growth in 4% O
2
but did result in a significant increase (4.9-fold;
P
< 0.001) in the rate of toxin production over that during anaerobic growth. At a
t
d
of 9 h, addition of 3.5% O
2
resulted in a 7.6-fold increase in specific TSST-1 production. When room air was sparged through a culture growing at a
t
d
of 9 h, TSST-1 production increased significantly (by 3.4-fold) over that during anaerobic growth. When a growth environment of 4% O
2
–remainder N
2
was studied, no increase in TSST-1 production was observed; this was also the case with 8% O
2
at gas-flow rates of 0.1, 0.2, and 0.4 liters/min. In all experiments, production of biomass (expressed as milligrams of cell dry weight per milliliter) increased, indicating that O
2
was metabolized by
S. aureus
. Addition of CO
2
to the gas mix (4% O
2
, 10% CO
2
, 86% N
2
) resulted in a 5.1- to 6.8-fold increase in TSST-1 production over that during anaerobic growth and a 3.6-fold increase over that during growth in an environment of 4% O
2
–remainder N
2
. The
agr
mutant strain tested produced 6.1-fold more specific TSST-1 in a growth environment of 4% O
2
–10% CO
2
–86% N
2
than during anaerobic growth. These data suggest that in this system, O
2
alone does not trigger production of TSST-1; rather, both CO
2
and O
2
are required.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference34 articles.
1. Arvidson
S.
Extracellular enzymes from Staphylococcus aureus Staphylococci and staphylococcal infections.
Easmon
C.
Adlam
C.
1983
745
808
Academic Press
London England
2. Summary of notifiable diseases, United States, 1996;Centers for Disease Control and Prevention;Morb. Mortal. Wkly. Rep.,1996
3. Regulation of exoprotein expression in Staphylococcus aureus by a locus (sar) distinct from agr;Cheung A. L.;Proc. Natl. Acad. Sci. USA,1992
4. Toxin involvement in toxic shock syndrome;Crass B.;J. Infect. Dis.,1986
5. Respiratory activity is essential for post-exponential-phase production of type 5 capsular polysaccharide by Staphylococcus aureus
Cited by
39 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献