Purification and characterization of two endopolygalacturonases from Sclerotinia sclerotiorum.
The endopolygalacturonase (EC 3.2.1.15) enzyme produced in vitro by Sclerotinia sclerotiorum were found to consist of numerous isoforms covering a broad pI range. Two of the isoforms, labelled PG2 and PG3, were purified using gel-filtration chromatography, isoelectric focusing and anion-exchange chromatography. The pIs of PG2 and PG3 were, respectively, 4.8 and 4.9. Their molecular weights were similar. Both enzymes hydrolysed 0.9% of the bonds in reaching a 50% reduction in viscosity. However, their enzymic parameters were different. Their amino acid compositions differed only in the aspartic acid-asparagine content. The N-terminal sequences differed at the fourth amino acid only. PG2 and PG3 exhibited a high level of glycosylation compared to a similar enzyme isolated from Aspergillus niger. Antibody raised against PG3 was shown to crossreact with PG2, but not with the enzyme purified from Aspergillus niger.
Waksman
G
G
Department of Microbiology, University of Bristol, Medical School U.K.
Keon
J P
JP
Turner
G
G
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001203:Ascomycota / Q000201:enzymology*; D015153:Blotting, Western; D003429:Cross Reactions; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011096:Polygalacturonase / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D013696:Temperature
D000596:Amino Acids; D011096:Polygalacturonase