RT Journal Article SR Electronic(1) A1 Droffner, Mary L. A1 Yamamoto, NobutoYR 1985 T1 Isolation of Thermophilic Mutants of Bacillus subtilis and Bacillus pumilus and Transformation of the Thermophilic Trait to Mesophilic Strains JF Microbiology, VO 131 IS 10 SP 2789 OP 2794 DO https://doi.org/10.1099/00221287-131-10-2789 PB Microbiology Society, SN 1465-2080, AB Summary: Thermophilic mutants were isolated from mesophilic Bacillus suhtilis and Bacillus pumilus by platinglarge numbers of cells and incubating them for several days at a temperature about 10 °C above the upper growth temperature limit for the parent mesophiles. Under these conditions we found thermophilic mutant strains that were able to grow at temperatures between 50 °C and 70 °C at a frequency of less than 10−10. The persistence of auxotrophic and antibiotic resistance markers in the thermophilic mutants confirmed their mesophilic origin. Transformation of genetic markers between thermophilic mutants and mesophilic parents was demonstrated at frequencies of 10−3 to 10−2 for single markers and about 10−7 for two unlinked markers. With the same procedure we were able to transfer the thermophilic trait from the mutant strains of Bacillus to the mesophilic parental strains at a frequency of about 10−7, suggesting that the thermophilic trait is a phenotypic consequence of mutations in two unlinked genes., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-131-10-2789