THE UTILIZATION OF RAPD-PCR FOR IDENTIFYING THERMOPHILIC AND MESOPHILIC BACILLUS SPECIES

A random amplified polymorphic DNA fingerprinting assay has been optim ized that is able to discriminate between numerous thermophilic and me sophilic bacillus species and strains. Included in the analyses are th ermophilic (able to grow at 55 degrees C) strains of Bacillus stearoth ermophilus, B. kaustrophilus, B. coagulans, B. sphaericus, B. thermode nitrificans, B. thermocatenulatus, B. thermoleovorans, B. licheniformi s, B. brevis, B. thermoglucosidasius, B. caldolyticus, B. caldotenax, B. caldovelox, B. thermocloacae and B. smithii. Mesophilic strains of B. pumilus, B. subtilis, B. megaterium, B. circulans, B. cereus and B. mycoides can also be used for fingerprinting with the assay. Increasi ng the concentration of primer from 0.2 to 2.0 mu M is shown to have a significant effect on increasing the number of amplification products that can be used for the discrimination or identification of individu al strains or species. It is suggested that this may be a general way of improving the resolution of a RAPD protocol. The optimized conditio ns have been used successfully to trace B. stearothermophilus, B. lich eniformis and other bacillus species and strains in an industrial sett ing.