Isolation and Characterization of thegroESandgroELgenes ofBacillus suhtilisMarburg

摘要

The complete set ofgroESandgroELgene homologues fromBacillus subtilisMarburg 168 was identified, cloned, and characterized. The nucleotide sequence indicated the presence of two open reading frames corresponding to thegroESandgroELgenes. The presumptive GroES and GroEL proteins were calculated to be polypeptides of 10,175 and 57,175Da, respectively, and showed extensive sequence similarities with the known GroES and GroEL proteins ofEscherichia coliandMycobacterium tuberculosis.A heat-inducible transcript initiated upstream of thegroEScoding region was identified by primer-extension analysis ofin vivotranscripts, indicating that the two genes consist of an operon. At least six heat-shock inducible proteins were identified in the cell extract of heat treatedB. subtilis.Two proteins of 10 and 60 kDa overproduced inB. subtiliscells carrying a multi-copygroESandgroELplasmid were demonstrated to correspond to two out of the six heat-shock inducible proteins. ThegroESandgroELgenes ofB. subtiliswere physically mapped on the 60° region of a 360° map and genetically mapped at the position of 40% linkage with thepurBlocus using PBS1 transduction of thegroELgenes tagged with a chloramphenicol resistance (chlr) marker.