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A newly isolated halotolerant Bacillus sp. VITP4 was investigated for the production of extracellular protease. 16S rRNA gene analysis identified it as Bacillus aquimaris. Enzyme secretion corresponded with growth (G_t, 38min) in the basal Zobell medium, reaching a maximum during stationary phase (630U/ml, 48h). Protease production was investigated in different salt concentrations (0–4M). While growth was optimum in the basal medium, higher levels of protease activity were observed in 0.5M salt medium (728U/ml, 48h) and 1M salt medium (796U/ml, 78h) with 21% and 32% increase in production, respectively. Salt concentrations above 2.5M did not support bacterial growth. The optimum pH and temperature for production were pH 7.5 and 37°C, respectively. A combination of peptone and yeast extract yielded optimum protease secretion. Inorganic nitrogen sources proved to be less favourable. Production …