Isolation and molecular identification of thermophilic bacteria from litter of mount Galunggung hot spring, Tasikmalaya, Indonesia

Thermophilic bacteria from litter deposited at Cipanas hot spring of mount Galunggung, Tasikmalaya, West Java, Indonesia, were isolated using a culture-dependent approach. Medium International Streptomyces Project (ISP) 1 solidified with gellan gum was used as an isolation medium. Isolation plates were incubated at 50°C for three weeks. The physicochemical analysis showed that the hot spring has a neutral pH and temperatures ranging from 50−56°C. A total of 16 bacterial isolates were obtained and purified. The analysis of partial 16S rRNA gene sequences data and phylogenetic analyses showed that they belong to Firmicutes and Proteobacteria phyla. The majority of bacterial isolates are spore-forming bacteria. The molecular identification based on the 16S rRNA gene sequence data showed that they belong to Aneurinibacillus thermoaerophilus (1); Brevibacillus gelatini (7); Bacillus licheniformis (1); Chelatococcus composti (1); Laceyella sacchari (2); Paenibacillus barengoltzii (1); and Pseudoxanthomonas taiwanensis (3). Percentage sequence similarities to their closest taxa were 91 to 99%. Phylogenetic analysis shed a light to the detection of candidates of novel taxa from litter of mount Galunggung hot spring.