Author(s)

Nanoukon Chimene^1*, Cachon Fresnel², Djèdatin Gustave¹, Sina Haziz³, Socohou Akim³, Dado Aurel^1,3, Kougblènou Enorck^1,3, Badé Farid³, Agbangla Clémént⁴, Baba-Moussa Lamine Saïd³

¹Laboratoire de Biologie Moléculaire et de Bio-Informatique Appliquée à la Génomique, Ecole Nationale Supérieure de Bioscience et de Biotechnologies Appliquées, Université Nationale des Sciences, Technologies, Ingénierie et Mathématique, Dassa-Zoumè, Bénin.
²Laboratoire de Biochimie, Biologie Moléculaire et Environnement, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi, Bénin.
³Laboratoire de Biologie et de Typage Moléculaire en Microbiologie, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi, Bénin.
⁴Laboratoire de Génétique Moléculaire et d’Analyse des Génomes, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi, Bénin.

The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA⁺ strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA⁻ SCCmec⁺ methicillin-resistant strains deserve to be sequenced for further studies.

Coagulase Negative Staphylococci, mecA, Staphylococcal Chromosomal Cassette

Chimene, N. , Fresnel, C. , Gustave, D. , Haziz, S. , Akim, S. , Aurel, D. , Enorck, K. , Farid, B. , Clémént, A. and Saïd, B. (2022) Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/Sô-Ava. American Journal of Molecular Biology, 12, 122-133. doi: 10.4236/ajmb.2022.123011.