DIFFERENTIATION BETWEEN SPORE-FORMING AND ASPOROGENIC BACTERIA USING A PCR AND SOUTHERN HYBRIDIZATION BASED METHOD

A set of molecular probes was devised to develop a method for screenin g for the presence of sequences homologous to three representative gen es exclusively involved in endosporulation. Based on known gene sequen ces, degenerate PCR primers were designed against spoOA and ssp. Exper imental conditions were devised under which homologs of both genes wer e consistently detected in endospore-forming bacteria, but not in aspo rogenic bacteria. The PCR amplification products and dpaA/B from Bacil lus subtilis were used as hybridization probes for Southern blots. Ide ntical conditions were used with the genomic DNA from endospore-formin g and asporogenic bacteria. We therefore concluded that the probes spe cifically detect the targeted sporulation genes and we obtained no ind ication that genes homologous to ssp, spoOA and dpaA/B are present in asporogenic bacteria. Thus, this assay can potentially be used to dete ct spore-forming bacteria in various kinds of samples and to distingui sh between bacteria containing sporulation genes and those who do not regardless of whether sporulation is observed or not. (C) 1997 Elsevie r Science B.V.