title: Purification, characterization, and production of two pectic transeliminases with protopectinase activity from Bacillus subtilis.
abstract: We found two enzymes that solubilize pectin from protopectin, tentatively named protopectinase-N (PPase-N) and protopectinase-R (PPase-R), in a culture filtrate of Bacillus subtilis IFO 3134. These enzymes were purified to homogeneity by hydrophobic, cation exchange and size exclusion chromatographies. The molecular weights of PPase-N and PPase-R were estimated to be 43,000 and 35,000, respectively, by SDS-PAGE. Their pIs were 9.4 and 8.2, respectively. These enzymes were stable in a wide range of pH and temperature. PPase-N and -R released water-soluble pectin by transeliminative cleavage of protopectin. According to their substrate specificities and modes of action, PPase-N and PPase-R could be classified as endo-pectate transeliminase (pectate lyase; EC 4.2.2.2) and endo-pectin transeliminase (pectin lyase; EC 4.2.2.10), respectively. Both enzymes were produced in a simple medium containing defatted soybean flour and phosphates. Production of PPase-N was repressed by addition of glucose while that of PPase-R was enhanced by phosphate.
authors.affiliation: Department of Agricultural Chemistry, College of Agriculture, University of Osaka Prefecture, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sakamoto
authors.forename: R A
authors.initials: RA
authors.lastname: Hours
authors.forename: T
authors.initials: T
authors.lastname: Sakai
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000302:isolation & purification* / Q000378:metabolism; D007527:Isoenzymes / Q000096:biosynthesis / Q000302:isolation & purification* / Q000378:metabolism; D008969:Molecular Sequence Data; D011133:Polysaccharide-Lyases / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D007527:Isoenzymes; D011133:Polysaccharide-Lyases; C027349:pectin lyase; C023911:pectate lyase