Over the past 12 years, culturomics, a high-throughput culture method, has been developed, considerably widening the repertoire of known cultured bacteria. An exhaustive database, including a list of microbes isolated by culture from human skin, was recently established by performing a review of the literature. The aim of the present study was to use the culturomics approach to explore the African skin microbiota. Skin swabs from the palms of human hands were collected between January and December 2016 from healthy subjects from the villages of Dielmo and Ndiop in rural Senegal. Three culture media were selected for the isolation of bacteria in aerobic conditions. Bacterial colonies were subjected to matrix-assisted laser desorption ionization-time of flight mass spectroscopy and the 16 S rRNA gene was sequenced for unidentified colonies. A total of 176 bacterial species were isolated. This increased the repertoire of bacterial species on the skin by 14.0%, by adding 71 bacteria, including seven new species. The culturomics approach characterizing microbial diversity has significantly changed our view of the skin microbiota, raising many important questions about the host-microorganism relationship and its relevance to skin diseases. In particular, the difference between the palm microbiota of these African populations (composed mainly of the genera Staphylococcus, Arthrobacter, Bacillus, and Microbacterium) and that of Western populations, whose main genera are Staphylococcus, Propionibacterium, Micrococcus, Corynebacterium, Enhydrobacter, and Streptococcus. This study demonstrates the need to continue to explore the skin microbiome using the culturomics approach.
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