Characterization of Thermophilic Bacteria Isolated from two Hot Springs in Jazan, Saudi Arabia

• Published in: Journal of pure & applied microbiology : an international research journal of microbiology Vol. 11; no. 2; pp. 743 - 752
• Main Authors: El-Gayar, Khaled E., Al Abboud, Mohamed A, M Essa, Ashraf M
• Format: Journal Article
• Language: English
• Published: Oriental Scientific Publishing Company 01.06.2017; Journal of Pure and Applied Microbiology
• Subjects: antibiotics; heavy metals; Hot springs; hydrolytic enzymes; Identification and classification; Observations; Thermophiles; Saudi Arabia
• ISSN: 0973-7510; 2581-690X
• DOI: 10.22207/JPAM.11.2.13

The capability of thermophilic microorganisms to flourish at high temperatures makes their enzyme systems ideal for various biotechnological applications. Based on the proteolytic and amylolytic activities, two thermophilic bacteria were isolated from hot springs in Jazan, Saudi Arabia. The antibiotic and heavy metals susceptibility patterns of the bacterial isolates were performed. According to the metabolic fingerprint, the bacterial isolates were identified as Brevibacterium linens and Bacillus subtilis. Moreover, the impact of temperature, substrate concentration, and some metal ions on the production of proteases and amylases from the bacterial strains was investigated. The maximum protease production was achieved at 50[degrees]C while the greatest amylase production was recorded at 30[degrees]C for both strains at a constant pH of 7.5. The highest enzyme production was recorded at 5% skimmed milk for protease of B. linens and 10% for B. subtilis while 0.6% starch was the optimum substrate concentration of amylase production of the two strains. Furthermore, [Ca.sup.2+] showed a simulative influence on protease production from the two strains whereas [Mg.sup.2+] and [Mn.sup.2+] demonstrated minor effect. On the other hand, [Ca.sup.2+], [Mg.sup.2+] and [Mn.sup.2+] demonstrated a positive effect on the amylase production from both strains. Keywords: Thermophiles, Hot springs, Hydrolytic enzymes, Antibiotics, Heavy metals.