DEVELOPMENT OF 16S RIBOSOMAL-RNA OLIGONUCLEOTIDE PROBES FOR BREVIBACTERIUM, MICROCOCCUS ARTHROBACTER AND MICROBACTERIUM/AUREOBACTERIUM USEDIN DAIRY STARTER CULTURES/

Oligonucleotide probes for bacteria of the cheese surface were develop ed. The complete 16S rRNA nucleotide sequences available from databank s of representatives of the genera Brevibacterium, Microbacterium/ Aur eobacterium and Micrococcus/Arthrobacter were aligned. Oligonucleotide probes were defined far the identification of these genera by selecti ng a common sequence of their 16S rRNA genes which are different from related genera like Corynebacterium, Propionibacterium or Bifidobacter ium. 82 strains were tested of which 70 were of the high DNA G+C branc h of bacterial evolution. II was shown by colony-hybridization experim ents, that the selected oligonucleotide probes targeted to the 16S rDN A region hybridized only with nucleic acids from strains of Brevibacte rium, Microbacterium/Aureobacterium and Micrococcus/Arthrobacter, resp ectively. For confirmation, a part of the 16S rDNA was amplified in vi tro using the polymerase chain reaction technique with two specific ol igonucleotides for each of these bacterial groups. The tested probes p rovide a highly efficient tool to investigate and identify these gener a within the coryneform group of bacteria. They were especially develo ped for analyzing the composition of the microflora of the cheese surf ace. The use of them may contribute substantially to the isolation and study of new strains of the these genera from natural habitats like c heese.