KOUADJO, C. G . Z. Institut National Polytechnique Houphouet-Boigny - Ecole Supérieure d’Agronomie (ESA) - Laboratoire de Sciences Agronomiqueset Génie Rural, Groupe de Recherche sur les Biotechnologies Végétale et Microbienne, Cote d’Ivoire , ZEZE, A. Institut National Polytechnique Houphouet-Boigny - Ecole Supérieure d’Agronomie (ESA) - Laboratoire de Sciences Agronomiqueset Génie Rural, Groupe de Recherche sur les Biotechnologies Végétale et Microbienne, Cote d’Ivoire

NATIVE CHROMIUM RESISTANT Staphylococci SPECIES FROM A FLY ASH DUMPING SITE IN SOUTH AFRICA HARBOR PLASMID pMOL28 DETERMINANTS

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Sixty-six chromium-resistant Staphylococci species belonging to S. epidermidis, S. aureus, S. saprophyticus and S. arlettae were previously isolated from a chromium-polluted Fly ash (FA) dumping site in South Africa. However the genetic mechanisms responsible for chromium resistance were not known. Polymerase chain reaction and DNA-DNA hybridization techniques were used to explore whether or not these staphylococcal strains exhibited chr determinants of plasmid pMOL28 that confers chromate resistance to Cupriavidus metallidurans. Genes ChrB_1 and ChrC were found to be present in the genomes of all the Staphylococci species. However, gene ChrA_1 was shown to be present only in the genome of S. aureus. These results showed that Chr genes could be distributed from Cupriavidus metallidurans (Gram negative bacteria) to Staphylococci species (Gram positive bacteria), probably by horizontal transfer.

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Fly Ash , chromium resistant bacteria , Staphylococci , Chr determinants , pMOL28

Agronomie Africaine

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