Culture dependent diversity and phylogeny of thermophilic bacilli from a natural hot spring reservoir in the Gir Forest, Gujarat (India)

Abstract

The thermophilic bacteria, isolated from a natural hot spring reservoir, Tulsi Shyam (Gir Forest, Gujarat, India) were characterized and diversified using the conventional approaches; Gram reaction, cell morphology, growth patterns, biochemical properties and antibiotic sensitivity. The bacteria were Gram pos itive, rod shaped and catalase positive. Majority of them produced amylase, indicating their ecological and biotechnological significance. The bacteria were further categorized on the basis of the amplified ribosomal DNA restriction analysis (ARDRA) patterns, generated by a tetracutter RE, HaeIII. As a polyphasic taxon omy approach, the isolates were clustered into 9 different groups, based on the conventional approaches and the ARDRA patterns. The further analysis was based on the 16S rRNA gene sequencing. The trend suggested that the phenotypic and phylogenetic diversity data considerably coincided. Overall, the part of Tulsi Shyam hot spring bacterial community represented by cultivated aerobic organotrophs can be clustered into 3 Gen era, Anoxybacillus, Geobacillus/Aeribacillus and Bacillus. They can further be grouped into sub clusters at the species level to establish phylogenetic and phenotypic relationship. Further, the diversity indices; Simpson's index, Dominance index and Shannon index indicated the species diversity, species richness and distribution evenness, respectively. A lower Simpson's index (0.1905) and higher Dominance index (0.8095) revealed sig nificant bacterial diversity. While a higher Shannon index (2.987) suggested evenness in the bacterial distri bution in different soil and water samples. The lower values of Berger Parker Dominance index and Ginni coefficient supported the trends of the Shannon index. As the studied habitat was not earlier explored for the bacterial diversity, the findings would significantly add to the knowledge of the cultivation based microbial diversity.

Temperature-controlled thermophilic bacterial communities in hot springs of western Sichuan, China

“…In light of limited information of microbial diversity provided by culture-dependent method, culture-independent techniques, primarily molecular methods, have been employed to phylogenetically characterize the microbial diversity in hot springs, and were proven to provide a more comprehensive assessment of microbial populations [ 18 ]. These approaches include direct 16S rRNA gene amplification and cloning, differentiation using amplified fragment length polymorphism (AFLP) [ 19 ], amplified ribosomal DNA restriction analysis (ARDRA) [ 20 ], denaturing gradient gel electrophoresis (DGGE) [ 21 ], and random amplified polymorphic DNA (RAPD) [ 22 ]. Numerous combined approaches have been also developed for the study of microbial communities, including scanning electron microscopy (SEM) combined with community level physiological profiles (CLPPs) [ 23 ] and other PCR/sequencing-based techniques [ 24 , 25 ].…”

Assessment of Culturable Microbial Diversity of Dholera Thermal Springs of Gujarat, India

“…Diversity indices tools have been used for the population of bacterial diversity, species richness and also better understanding about microbial community (Kim et al, 2017). Kikani et al (2015), calculated the various diversity indices of Tulsi Shyam hot spring, Gujarat. They have given information about the evenness in their distribution, community structure and species richness (Kikani et al, 2015).…”

“…Kikani et al (2015), calculated the various diversity indices of Tulsi Shyam hot spring, Gujarat. They have given information about the evenness in their distribution, community structure and species richness (Kikani et al, 2015). 16S rRNA gene sequencing techniques have been used for the identification of bacteria and phylogenetic analysis as the "gold standard" (Ludwig & Schleifer 1999).…”