Document Detail

Staphylococcal enterotoxin B and nuclease production under controlled dissolved oxygen conditions.
MedLine Citation:
PMID:  4213939     Owner:  NLM     Status:  MEDLINE    
Enterotoxin B, nuclease, and total exoprotein production by Staphylococcus aureus strain S-6 was studied in a 0.5-liter fermentor system. While these extracellular products were elaborated over a wide range of aeration rates, maximal production occurred within the very narrow range of 125 to 150 cm(3) of air per min. The levels attained at the optimal aeration rate were not increased by maintaining a constant pH, although yield of enterotoxin:cell mass was highest at a constant pH of 7.0. During the growth cycle of the cultures, when aeration rate alone or aeration rate and pH were held constant, the dissolved oxygen (DO) levels, initially set at 100% of saturation, decreased to 5 to 10% 4 to 5 h after inoculation. The oxygen demand of the culture then maintained this level for an additional 4 to 6 h. This interval of low DO was characterized by maximal growth and exoprotein production. When the DO was controlled at a constant value throughout growth (by increasing or decreasing the airflow rate as appropriate), the culture demonstrated different optima for maximal growth and exoprotein production. A constant DO of 100% stimulated growth to extremely high densities, but the accumulation of toxin and nuclease was not observed. On the other hand, maintaining constant DO levels at 50 or 10% raised exoprotein levels higher than those achieved in a culture grown at the optimal aeration rate. Compared to the optimal aeration rate culture, the 10% DO culture yielded 20% more nuclease, 25% more toxin, and 40 to 50% more total exoprotein. These results indicate that it is the DO and not the aeration rate, per se, that is influential in controlling growth, toxin, nuclease, and total exoprotein production.
D F Carpenter; G J Silverman
Related Documents :
3112199 - Calcium alginate-immobilized cultures of lactic streptococci are protected from bacteri...
8810509 - Autonomous metabolic oscillation in continuous culture of saccharomyces cerevisiae grow...
21168399 - Meiotic maturation of vitrified immature chousingha (tetracerus quadricornis) oocytes r...
11170489 - Salt accumulation resulting from base added for ph control, and not ethanol, limits gro...
16598829 - Pyrimidine base supplementation effects curdlan production in agrobacterium sp. atcc 31...
18576509 - Growth inhibitory and lethal effects of ethanol on escherichia coli.
16466989 - Inhibition of lymphokine-activated killer cells generation in vitro by soluble factors ...
12294519 - International migration. world order or disorder?
1396759 - Evaluation of a commercial enzyme immunoassay kit for the detection of clostridium diff...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Applied microbiology     Volume:  28     ISSN:  0003-6919     ISO Abbreviation:  Appl Microbiol     Publication Date:  1974 Oct 
Date Detail:
Created Date:  1975-01-08     Completed Date:  1975-01-08     Revised Date:  2010-09-13    
Medline Journal Info:
Nlm Unique ID:  7605802     Medline TA:  Appl Microbiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  628-37     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bacterial Proteins / biosynthesis
Endonucleases / biosynthesis*
Enterotoxins / biosynthesis*
Hydrogen-Ion Concentration
Staphylococcus / enzymology,  growth & development,  metabolism*
Reg. No./Substance:
0/Bacterial Proteins; 0/Enterotoxins; 7782-44-7/Oxygen; EC 3.1.-/Endonucleases

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  The genetic structure of natural populations of Drosophila melanogaster. XII. Linkage disequilibrium...
Next Document:  Replication of measles virus: continued synthesis of nucleocapsid RNA and increased synthesis of mRN...