title: Overexpression of the pectin lyase gene of Pseudomonas marginalis in Escherichia coli and purification of the active enzyme.
abstract: A pectin lyase gene (pnl) of Pseudomonas marginalis was cloned and overexpressed in Escherichia coli BL21(DE3). The pnl gene was amplified by PCR, inserted into pET29c with a six-His tag and the overproduced active enzyme was purified almost to homogeneity using a Ni(2+)-nitrilotriacetate-agarose column. The purified pectin lyase (PNL; EC 4.2.2.10, family 1) is inhibited by NAD+ (at concentrations above 0.25 mM), NADH or dithiothreitol. Evidence for the existence of a heat-labile protein inhibitor of PNL is also reported. The DNA-binding ability of PNL was demonstrated by DNA-retardation experiments. The partially purified enzyme was incubated with plasmid DNA and the complex was shifted to a higher molecular mass. Analysis of the electroeluted proteins from the protein-DNA complex revealed that one of the electroeluted protein bands was PNL. Antibodies against the overexpressed PNL were also prepared and partially purified.
authors.affiliation: Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece.
authors.forename: Rigini
authors.initials: R
authors.lastname: Papi
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kyriakidis
mesh_terms: D004789:Enzyme Activation; D004926:Escherichia coli / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D011133:Polysaccharide-Lyases / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D011549:Pseudomonas / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D011133:Polysaccharide-Lyases; C027349:pectin lyase