A novel extra-cellular lipase from Bacillus coagulans MTCC-6375 was puriWed 76.4-fold by DEAE anion exchange and Octyl
Sepharose chromatography. The puriWed enzyme was found to be electrophoretically pure by denaturing gel electrophoresis and possessed
a molecular mass of approximately 103 kDa. The lipase was optimally active at 45 °C and retained approximately 50% of its original
activity after 20 min of incubation at 55 °C. The enzyme was optimally active at pH 8.5. Mg2+, Cu2+, Ca2+, Hg2+, Al3+, and Fe3+ at
1 mM enhanced hydrolytic activity of the lipase. Interestingly, Hg2+ ions resulted in a maximal increase in lipase activity but Zn2+ and
Co2+ ions showed an antagonistic eVect on this enzyme. EDTA at 150 mM concentration inhibited the activity of lipase but Hg2+ or Al3+
(10 mM) restored most of the activity of EDTA-quenched lipase. Phenyl methyl sulfonyl Xuoride (PMSF, 15 mM) decreased 98% of original
activity of lipase. The lipase was more speciWc to p-nitrophenyl esters of 8 (pNPC) and 16 (pNPP) carbon chain length esters. The
lipase had a Vmax and Km of 0.44 mmol mg¡1 min¡1
and 28 mM for hydrolysis of pNPP, and 0.7 mmol mg¡1 min¡1
and 32 mM for hydrolysis
of pNPC, respectively.
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