EFFECT OF METAL IONS ON PRODUCTION AND ACTIVITY OF NEWLY ISOLATED BACILLUS SUBTILIS C43

Abstract

An efficient phytase producing bacteria was isolated from soil samples of Hyderabad, A.P. and was identified as Bacillus subtilis C43. Phytases are the enzymes which catalyzes the hydrolysis of phytic acid into myo-inositol derivatives and inorganic phosphate. The role of influence of metals on the production and activity of phytase from the isolate was checked. The role of influence of metals on the enzyme production was observed by the addition of metallic salts to the production medium. Among the different cations, only Ca2+ ions at a concentration of 5mM significantly (P< 0.05) improved the secretion of phytase into the medium. All the other metal ions at various concentrations used considerably inhibited the enzyme production. However, there was no significant (P>0.05) effect upon addition of 5mM of Mn2+ in the production media. Metal ions have also been shown to modulate phytase activity. In our study, the enzyme activity was significantly (P<0.05) increased by the addition of metal ions Ca+2, Na+, Cu+2, K+, Co+2 and Ni+2 ; whereas metal ions Mg+2, Fe+2 and Mn+2 and EDTA significantly(P<0.05) inhibited the activity. However, there was no significant (P>0.05) effect of Zn2+ on the phytase activity. Of all those tested, EDTA was the agent that greatly inhibited the enzyme activity as it caused 52% reduction in activity.