Skip to main content
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1983 Jan;153(1):436–442. doi: 10.1128/jb.153.1.436-442.1983

Dielectric characterization of forespores isolated from Bacillus megaterium ATCC 19213.

R E Marquis, G R Bender, E L Carstensen, S Z Child
PMCID: PMC217391  PMID: 6401285

Abstract

Isolated stage III forespores of Bacillus megaterium ATCC 19213 in aqueous suspensions were nearly as dehydrated as mature spores, as indicated by low dextran-impermeable volumes of ca. 3.0 ml per g (dry weight) of cells compared with values of ca. 2.6 for mature spores and 7.3 for vegetative cells. The forespores lacked dipicolinate, had only minimal levels of calcium, magnesium, manganese, potassium, and sodium, and were more heat sensitive than vegetative cells. The effective homogeneous conductivities and dielectric constants measured over a frequency range of 1 to 200 MHz indicated that the inherent conductivities of the forespores were unusually low, in keeping with their low mineral contents, but that the forespores could be invaded by environmental ions which could penetrate dielectrically effective membranes. Overall, our findings support the view that the dehydration of a forespore during stage III of sporogenesis may be the result of ion movements out of the forespore into the sporangium.

Full text

PDF
436

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Beaman T. C., Greenamyre J. T., Corner T. R., Pankratz H. S., Gerhardt P. Bacterial spore heat resistance correlated with water content, wet density, and protoplast/sporoplast volume ratio. J Bacteriol. 1982 May;150(2):870–877. doi: 10.1128/jb.150.2.870-877.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Carstensen E. L., Marquis R. E., Child S. Z., Bender G. R. Dielectric properties of native and decoated spores of Bacillus megaterium. J Bacteriol. 1979 Dec;140(3):917–928. doi: 10.1128/jb.140.3.917-928.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Carstensen E. L., Marquis R. E., Gerhardt P. Dielectric study of the physical state of electrolytes and water within Bacillus cereus spores. J Bacteriol. 1971 Jul;107(1):106–113. doi: 10.1128/jb.107.1.106-113.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Gerhardt P., Beaman T. C., Corner T. R., Greenamyre J. T., Tisa L. S. Photometric immersion refractometry of bacterial spores. J Bacteriol. 1982 May;150(2):643–648. doi: 10.1128/jb.150.2.643-648.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. SLEPECKY R., FOSTER J. W. Alterations in metal content of spores of Bacillus megaterium and the effect on some spore properties. J Bacteriol. 1959 Jul;78(1):117–123. doi: 10.1128/jb.78.1.117-123.1959. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Scott I. R., Ellar D. J. Study of calcium dipicolinate release during bacterial spore germination by using a new, sensitive assay for dipicolinate. J Bacteriol. 1978 Jul;135(1):133–137. doi: 10.1128/jb.135.1.133-137.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Wilkinson B. J., Deans J. A., Ellar D. J. Biochemical evidence for the reversed polarity of the outer membrane of the bacterial forespore. Biochem J. 1975 Dec;152(3):561–569. doi: 10.1042/bj1520561. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES