Abstract
Mature bacterial spores can be manipulated by chemical pretreatments between states sensitive and resistant to dry heat. The two chemical forms of the spore differ in dry-heat resistance by about an order of magnitude. Log survivor curves for each chemical state were approximately straight lines. The temperature dependence of dry-heat resistance for each chemical state was similar to that usually found for dry-heat resistance. A method of testing spore resistance to dry heat has been designed to minimize artifacts resulting from (i) change of chemical state during the test, (ii) effects of water vapor activity, (iii) incomplete recovery of spores from the test container and clumping of spores. Implications of the existence of different chemical resistance states for experimental strategy and testing of dry-heat resistance are discussed.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- ALDERTON G., SNELL N. Base exchange and heat resistance in bacterial spores. Biochem Biophys Res Commun. 1963 Jan 31;10:139–143. doi: 10.1016/0006-291x(63)90039-1. [DOI] [PubMed] [Google Scholar]
- ALDERTON G., THOMPSON P. A., SNELL N. HEAT ADAPTATION AND ION EXCHANGE IN BACILLUS MEGATERIUM SPORES. Science. 1964 Jan 10;143(3602):141–143. doi: 10.1126/science.143.3602.141. [DOI] [PubMed] [Google Scholar]
- Angelotti R., Maryanski J. H., Butler T. F., Peeler J. T., Campbell J. E. Influence of spore moisture content on the dry-heat resistance of Bacillus subtilis var. niger. Appl Microbiol. 1968 May;16(5):735–745. doi: 10.1128/am.16.5.735-745.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GRECZ N., ANELLIS A., SCHNEIDER M. D. Procedure for cleaning of Clostridium botulinum spores. J Bacteriol. 1962 Sep;84:552–558. doi: 10.1128/jb.84.3.552-558.1962. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Murrell W. G., Scott W. J. The heat resistance of bacterial spores at various water activities. J Gen Microbiol. 1966 Jun;43(3):411–425. doi: 10.1099/00221287-43-3-411. [DOI] [PubMed] [Google Scholar]
- Pheil C. G., Pflug I. J., Nicholas R. C., Augustin J. A. Effect of various gas atmospheres on destruction of microorganisms in dry heat. Appl Microbiol. 1967 Jan;15(1):120–124. doi: 10.1128/am.15.1.120-124.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SACKS L. E., ALDERTON G. Behavior of bacterial spores in aqueous polymer two-phase systems. J Bacteriol. 1961 Sep;82:331–341. doi: 10.1128/jb.82.3.331-341.1961. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Snell N. Direct counts of bacterial spores on membrane filters under phase optics. Appl Microbiol. 1968 Feb;16(2):436–436. doi: 10.1128/am.16.2.436-.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]