Environmental and nutritional parameters controlling the biosynthesis of thermostable alkaline protease [TAP] from Bacillus sterrothurmophilos, S-WN 1616 B isolated from Wady El - Natroon lakes in Egypt

ABSTRACT

A special study was undertaken concerning the productivity of thermo- alkaline protease[s] [TAP] by the proteolytic thermoalkalophilic Bacillus stearothermophilus S-WN1616B isolated from Wady El-Natroon in Egypt. Optimal parameters controlling TAP productivity were inoculum size [0.23x109 CFU/ml], incubation period [30 days], incubation temperature [55C], pH [10-10.2] and NaCl 3%. Although L-threonine, Ca-nitrate, gelatin, peptone pantothenic acid and Zn++ enhanced [TAP] formation while added separately to gelatin-production medium, yet their elimination in addition to the absence of all ingredients of medium gave evidence that only gelatin in tap water stimulated the highest yield of [TAP] under other optimal specified conditions. Data emphasized the inducing role of gelatin on TAP-biosynthesis at relatively high temperature and pH value