An organic-solvent-tolerant esterase from turkey pharyngeal tissue.

Stability is a crucial factor for the application of enzymes in biotechnology. Investigation of esterase activity in the pharyngeal tissue of turkey (Meleagris gallopavo), showed that optimum catalytic conditions of pure enzyme were 50 degrees C and pH 8.5. Turkey pharyngeal esterase (TPE) retained 75% of its maximum activity after incubation for 1h at 50 degrees C. Thermostability of the esterase was enhanced in the presence of an analogous substrate: phosphatidylcholine. TPE had a wide pH range of stability (pH 4.0-10.0). Esterase activity was compatible with the presence of organic solvents. Furthermore, the hydrolysis was found to be slightly activated by Ca(2+), but drastically reduced by Zn(2+) and Cu(2+). Phenylmethanesulphonyl fluoride (PMSF) a serine-specific inhibitor, strongly inhibited the esterase activity, whereas beta-mercaptoethanol, a thiol group inhibitor, did not show any effect on the activity. Esterase activity in the presence of organic solvents, as well as in acidic and alkaline pHs and at high temperatures makes it a good candidate for its application in non-aqueous biocatalysis. Copyright 2009 Elsevier Ltd. All rights reserved.