Molecular characterization of thermophilic prokaryotes from Chinyunyu hot spring in Zambia

Hot springs are among some of the naturally-occurring extreme environments that have generated considerable interest in microbial ecologists worldwide even though there is very little information on hotspring ecosystems in Zambia. Thermophilic prokaryotes present in such extreme habitats are considered valuable sources of biotechnological products including thermally-stable enzymes applied in many research and manufacturing processes. Fifteen water samples were aseptically collected from three different sampling points at three different temperatures of 50C, 55C and 60C at Chinyunyu hot spring in Zambia. The recorded pH of the water at the sampling time was 9.0. One hundred microlitres of each sample was inoculated on nutrient agar medium and incubated at 50C, 55C and 60C. A total of 13 phenotypically distinct isolates were identified from all the three incubation temperatures. The isolated colonies were subsequently cultured at 55°C and pH of 7.0. Their genomic DNA was PCR-amplified using 16S rRNA primers and sequenced by the Sanger dideoxy chain termination method. Amplicon sequences were analyzed using Basic Local Alignment Search Tool (BLAST) algorithm. All the thirteen isolates were Gram-positive, catalase positive, rod-shaped cells. All isolates belonged to the bacterial phylum Firmicutes and seven were affiliated to the genus Anoxybacillus while six were affiliated to the genus Bacillus. The study revealed that Chinyunyu hot spring harbors genetically diverse thermophilic prokaryotes which could be amenable to further studies to exploit the hot spring microbiome for its biotechnological potential