Characterization and physicochemical properties of a lipase from Pseudomonas mendocina 3121–1

Abstract

The lipase from Pseudomonas mendocina 3121-1 was found to be homogeneous with a molecular mass of 30 kDa by SDS/PAGE. It is composed of two identical subunits. A molecular mass of 62 kDa was determined by gel chromatography on a Toyopearl HW-55F column. Some physicochemical properties of the lipase were investigated using p-nitrophenyl butyrate (p-NPB), Tween 80 solution and Sigma olive-oil emulsion as substrates. The optimum temperature was determined to be 52 degrees C with p-NPB, in the range 50-60 degrees C with Tween 80 and in the range 50-65 degrees C with olive-oil emulsion. The optimum pH was determined to be in the pH range 7.2-7.5, both with Tween and the emulsion, but was unusually alkaline (pH 9.5) with p-NPB. The enzyme was activated for p-NPB hydrolysis by thermal treatment up to 60 min at 60 degrees C, pH 7.0-8.2, but was rapidly inactivated at 70-80 degrees C and at pH 7.0. The lipase was shown to be more thermolabile at 60 degrees C with respect to other two substrates. Using the emulsified substrate, no activity was obtained after preincubating the enzyme for 30 min at 70 degrees C. The enzyme was found to be pH-tolerant when stored at 20 degrees C, pH 6.3-10.3 (100 mM Briton-Robson buffer) as the half-life (t(1/2)) was more than 240 h when p-NPB was used as the substrate. By contrast, the pH-stability range was more narrow (pH 8.0-10.5) with olive-oil emulsion. The effect of various metal ions and EDTA depended on the nature of the substrate.

Characterization of an extracellular alkaline lipase from Pseudomonas mendocina M‐37

“…with a temperature optima of 45 °C and 50 °C have been reported [7,13,[16][17][18]. The optimum temperature was found to be 52 °C ( p-NPB), 50-60 °C with Tween 80 and in the range 50-65 °C with olive-oil emulsion in Pseudomonas mendocina 3121-1 [19]. Lower temperature optima of 37 °C and 40 °C were reported in P. mendocina PK-12CS [12], Pseudomonas pseudomallei 12SM [10] and in P. pseudoalkaligenes F-111 [20], and still lower i.e.…”

Isolation, Optimisation and Purification of Lipase Production by Pseudomonas Aeruginosa

“…Calcium ion, especially, is used in Ca +2 binding processing which impact to position specificity on active site [1]. Same lipases produced by Pseudomonas sp.…”

Thermostable feruloyl esterase for the bioproduction of ferulic acid from triticale bran

“…The experimental values were used to calculate the half-life time of the enzyme. The pH optimum was determined over a pH range of 5-11 in 50 mM Britton and Robinson's universal buffer (Surinenaite et al 2002).…”