The Himalayan Mountains are placed among the globally recognized biodiversity hot spots. While the Indian Himalayan Region (IHR) has been subjected to extensive studies on plant and animal biodiversity, microbial diversity is now being studied for its bioprospection. The present paper deals with the evaluation of bacterial diversity in high-altitude soil samples from IHR following polyphasic approach including comparison between the MALDI-TOF mass spectrometry and 16S rRNA gene sequencing for species-level identification. Initially, a culture collection of large number of bacterial isolates was established in the laboratory. Performing morphological and biochemical screenings, sixty-one representative isolates were selected for mass spectrometry and gene sequencing. Both the methods emerged with bacterial identification showing maximum number of Bacillus followed by Pseudomonas species. The other frequently isolated strains belonged to the genera Alcaligenes, Carnobacterium, Lysinibacillus, Microbacterium, Paenarthrobacter, Rhodococcus, Serratia and Stenotrophomonas. Although the MALDI-TOF technique appeared to be advantageous as less time-consuming in comparison with 16S rRNA-based method, the discrepancies at species level indicated the limited database of MALDI Biotyper and species complexity in the genera. The remarkable characteristics of the bacterial isolates were their tolerance to wide range of pH and temperature. Their potential to produce industrially valuable enzymes indicated their importance in bioprospection. Accessioning of these bacterial isolates in microbial culture collections is a cautious effort for their availability to conduct advanced research on these cold-adapted bacteria in future.
Enzymes from thermophilic bacteria have received great attention for their potential applications in various industrial sectors. The present study deals with the production of five thermozymes (amylase, lipase, xylanase, protease and cellulase) from 10 thermophilic bacterial species, originally isolated from two hot springs namely Soldhar and Ringigad in Uttarakhand Himalaya, India. The bacterial isolate GBPI_25 produced maximum amylase (1217.86 U/ml) at 45 °C and 5 pH, GBPI 3 produced maximum lipase (22.59 U/ml) at 65 °C and 9 pH, GBPI_25 produced maximum xylanase (98.07 U/ml) at45 °C and 9 pH, GBPI_35 produced maximum protease (16.66 U/ml) at 55 °C and 9 pH, and GBPI 4 produced maximum cellulose (108.68 U/ml) at 45 °C and 5 pH. Crude enzyme preparations showed thermal and pH activities at broad temperature and pH range between 10-100 °C and 3-11 pH, respectively, with different temperature and pH optima. Amylase, xylanase and cellulase showed maximum activity at 50 °C while lipase and protease showed higher activity at 40 and 60 °C, respectively. Enzyme activity at wide temperature range-cellulase and protease from 10-100 °C, amylase and xylanasefrom10-90 °C, and lipase activity from 10-80 °C were the remarkable records from this study. Similarly, pH range for amylase and lipase activity was recorded from 4-11, for xylanase from 3-9, and for protease and cellulase from 3-10. All the thermozymes showed maximum stability at 40 °C and pH 5 except cellulase that showed higher stability at40 °C and neutral pH.
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