Abstract
Factors affecting the susceptibility of Bacteroides fragilis subsp. fragilis to low temperature were examined. Predetermined numbers of cells were spread on agar media or suspended in enriched Trypticase soy broth and exposed to low temperature under both aerobic and anaerobic conditions. Exposure of 18-h growth of a freshly isolated B. fragilis strain to 4 degrees C aerobically or anaerobically resulted in a loss of at least 50% viability after 12 h. B. fragilis cells in early growth (6 h) were more tolerant to exposure at 4 degrees C than older cells (18 h). When the freshly isolated strain was repeatedly subcultured in the laboratory it was uniformly more cold tolerant than fresh clinical isolates. The incorporation of 1.0 M sucrose and 5 mM magnesium chloride into liquid media partially alleviated the lethal effects of cold temperature on B. fragilis subsp. fragilis.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bartlett J. G., Sullivan-Sigler N., Louie T. J., Gorbach S. L. Anaerobes survive in clinical specimens despite delayed processing. J Clin Microbiol. 1976 Feb;3(2):133–136. doi: 10.1128/jcm.3.2.133-136.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GORRILL R. H., McNEIL E. M. The effect of cold diluent on the viable count of Pseudomonas pyocyanea. J Gen Microbiol. 1960 Apr;22:437–442. doi: 10.1099/00221287-22-2-437. [DOI] [PubMed] [Google Scholar]
- Hegarty C. P., Weeks O. B. Sensitivity of Escherichia coli to Cold-Shock during the Logarithmic Growth Phase. J Bacteriol. 1940 May;39(5):475–484. doi: 10.1128/jb.39.5.475-484.1940. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Loesche W. J. Oxygen sensitivity of various anaerobic bacteria. Appl Microbiol. 1969 Nov;18(5):723–727. doi: 10.1128/am.18.5.723-727.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STRANGE R. E., DARK F. A. Effect of chilling on Aerobacter aerogenes in aqueous suspension. J Gen Microbiol. 1962 Dec;29:719–730. doi: 10.1099/00221287-29-4-719. [DOI] [PubMed] [Google Scholar]
- Tally F. P., Stewart P. R., Sutter V. L., Rosenblatt J. E. Oxygen tolerance of fresh clinical anaerobic bacteria. J Clin Microbiol. 1975 Feb;1(2):161–164. doi: 10.1128/jcm.1.2.161-164.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Traci P. A., Duncan C. L. Cold shock lethality and injury in Clostridium perfringens. Appl Microbiol. 1974 Nov;28(5):815–821. doi: 10.1128/am.28.5.815-821.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]