The gene encoding Schizophyllum commune glucuronoyl esterase was identified in the scaffold 17 of the genome, containing two\r\nintrons of 50 bp and 48 bp, with a transcript sequence of 1179 bp. The gene was synthesized and cloned into Pichia pastoris\r\nexpression vector pGAPZa to achieve constitutive expression and secretion of the recombinant enzyme in soluble active form.\r\nThe purified protein was 53 kD with glycosylation and had an acidic pI of 3.7. Activity analysis on several uronic acids and their\r\nderivatives suggests that the enzyme recognized only esters of 4-O-methyl-D-glucuronic acid derivatives, even with a 4-nitrophenyl\r\naglycon but did not hydrolyze the ester of D-galacturonic acid. The kinetic values were Km 0.25 mM, Vmax 16.3 �µM�·min-1, and kcat\r\n9.27 s-1 with 4-nitrophenyl 2-O-(methyl 4-O-methyl-a-D-glucopyranosyluronate)-�Ÿ-D-xylopyranoside as the substrate.
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