Archana Singh and Ved Pal Singh*
Applied Microbiology and Biotechnology Laboratory, Department of Botany, University of Delhi, Delhi- 110 007, India
* E-mail: vpsingh_biology@rediffmail.com
Abstract: Amylase finds a wide range of applications in starch industries, i.e., baking, brewing, distillery. The wild-type (1227) and mutant strains (1261 and 1286) of Thermoactinomyces vulgaris were screened for the production of amylase using 1% soluble starch. The maximum production of amylase was observed after 12 h of incubation at 50ºC in wild-type strain 1227 of T. vulgaris. The amylase was found to be thermophilic, exhibiting its optimal activity at 75ºC and at pH 6.0 in this obligate thermophile; and it preferred soluble starch as its substrate. Among the metal ions tested, Mn2+ was most stimulatory, while Hg2+ was most inhibitory to the activity of amylase. Thus, T. vulgaris amylase is a thermophilic metalloenzyme, requiring Mn2+ for its high-temperature catalysis, which can be exploited for amylase-based industries of diverse interests.
Keywords: Amylase, Metalloenzyme, Thermoactinomyces vulgaris, Thermophilic amylase
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