A new enrichment method for isolation of Bacillus thuringiensis from diverse sample types

Appl Biochem Biotechnol. 2013 May;170(1):58-66. doi: 10.1007/s12010-013-0145-y. Epub 2013 Mar 7.

Abstract

New or more efficient methodologies having different principles are needed, as one method could not be suitable for isolation of organisms from samples of diverse types and from various environments. In present investigation, growth kinetics study revealed a higher germination rate, a higher growth rate, and maximum sporulation of Bacillus thuringiensis (Bt) compared to other Bacillus species. Considering these facts, a simple and efficient enrichment method was devised which allowed propagation of spores and vegetative cells of Bt and thereby increased Bt cell population proportionately. The new enrichment method yielded Bt from 44 out of 58 samples. Contrarily, Bt was isolated only from 16 and 18 samples by sodium acetate selection and dry heat pretreatment methods, respectively. Moreover, the percentages of Bt colonies isolated by the enrichment method were higher comparatively. Vegetative whole cell protein profile analysis indicated isolation of diverse population of Bt from various samples. Bt strains isolated by the enrichment method represented novel serovars and possibly new cry2 gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus thuringiensis / genetics
  • Bacillus thuringiensis / growth & development
  • Bacillus thuringiensis / isolation & purification*
  • Bacterial Proteins / genetics
  • Colony Count, Microbial
  • Culture Media
  • Hemolysin Proteins / genetics
  • Hot Temperature
  • Sodium Acetate
  • Soil Microbiology*
  • Spores, Bacterial / genetics
  • Spores, Bacterial / growth & development
  • Spores, Bacterial / isolation & purification*

Substances

  • Bacterial Proteins
  • Culture Media
  • Hemolysin Proteins
  • Sodium Acetate