Isolation and Characterization of a Novel Thermophilic-Organic Solvent Stable Lipase From Acinetobacter baylyi

Abstract

The benzene tolerant Acinetobacter baylyi isolated from marine sludge in Angsila, Thailand could constitutively secrete lipolytic enzymes. The enzyme was successfully purified 21.89-fold to homogeneity by ammonium sulfate precipitation and gel-permeable column chromatography with a relative molecular mass as 30 kDa. The enzyme expressed maximum activity at 60 degrees C and pH 8.0 with p-nitrophenyl palmitate as a substrate and found to be stable in pH and temperature ranging from 6.0-9.0 to 60-80 degrees C, respectively. A study on solvent stability revealed that the enzyme was highly resisted to many organic solvents especially benzene and isoamyl alcohol, but 40% inhibited by decane, hexane, acetonitrile, and short-chain alcohols. Lipase activity was completely inhibited in the presence of Fe(2+), Mn(2+), EDTA, SDS, and Triton X-100 while it was suffered detrimentally by Tween 80. The activity was enhanced by phenylmethylsulfonyl fluoride (PMSF), Na(+), and Mg(2+) and no significant effect was found in the presence of Ca(2+) and Li(+). Half of an activity was retained by Ba(2+), Ag(+), Hg(+), Ni(2+), Zn(2+), and DTT. The enzyme could hydrolyze a wide range of p-nitrophenyl esters, but preferentially medium length acyl chains (C(8)-C(12)). Among natural oils and fats, the enzyme 11-folds favorably catalyzed the hydrolysis of rice bran oil, corn oil, sesame oil, and coconut oil in comparison to palm oil. Moreover, the transesterification activity of palm oil to fatty acid methyl esters (FAMEs) revealed 31.64 +/- 1.58% after 48 h. The characteristics of novel A. baylyi lipase, as high temperature stability, organic solvent tolerance, and transesterification capacity from palm oil to FAMEs, indicate that it could be a vigorous biocatalyzer in the prospective fields as bioenergy industry or even in organic synthesis and pharmaceutical industry.

Optimization of Lipase Production by Thermo-Alkalophilic Bacillus sp. 8C

“…Thermophilic lipases are of special interest for industrial applications due to their stability and high activity at higher temperatures and being stable in presence of chemicals (Messias et al, 2009;Uttatree et al, 2010). Lipases being third largest selling group of enzymes with more than 1000 t of annual production and approaching to a billion dollar business.…”

“…High quality and low energy consumption of lipase catalyzed reactions make them superior over conventional steam splitting methods operating at high temperature and pressure (Treichel et al, 2010). These characteristics of lipases increased their demand in different industries including food and dairy, detergent, cosmetics, leather, paper and pulp, biodiesel and pharmaceutical (Hasan et al, 2007).Thermophilic lipases are of special interest for industrial applications due to their stability and high activity at higher temperatures and being stable in presence of chemicals (Messias et al, 2009;Uttatree et al, 2010). Lipases being third largest selling group of enzymes with more than 1000 t of annual production and approaching to a billion dollar business.…”

Immobilization of Lipase-Producing Bacteria Acinetobacter baumannii on Paddy Straw Powder

“…Some researchers report lipase production by bacteria from the genus of Acinetobacter, such as Acinetobacter baumannii BD5 14 , Acinetobacter baylyi 15 , and Acinetobacter junii 16 . Bacteria of this genus can also be used in the biodegradation of organic and inorganic waste, and are able to produce biomolecules such as polysaccharides, polyesters, and biosurfactant 17 .…”

“…The existence of Ca 2+ on the activated paddy straw powder also increases the activity of lipase produced by immobilized bacteria. Lipase generally does not require cofactors like most other enzymes, however cation divalent such as Ca 2+ is often found to increase the activity of lipase 15,19,20,21 .…”

“…Uttatree et al reported lipase from Acinetobacter baylyi isolated from sea mud in Angsila, Thailand has optimal activity at pH 8.0 and is stable in the pH range 6-9 15 . Furthermore, lipase produced by Acenitobacter johnsonii strain LP28 showes good activity in the range pH 8-11 with an optimum activity at pH 9 24 .…”