title: A flax-retting endopolygalacturonase-encoding gene from Rhizopus oryzae.
abstract: A polygalacturonase from the filamentous fungus Rhizopus oryzae strain sb (NRRL 29086), previously shown to be effective in the retting of flax fibers, was shown by the analysis of its reaction products on polygalacturonic acid to be an endo-type. By zymogram analysis, the enzyme in the crude culture filtrate appeared as two active species of 37 and 40 kD. The endopolygalacturonase-encoding gene was cloned in Escherichia coli and its translated 383-amino acid sequence found to be identical to that of a presumed exopolygalacturonase found in R. oryzae strain YM9901 and 96% identical to a hypothetical protein (RO3G_04731.1) in the sequenced genome of R. oryzae strain 99-880. Phylogenetic analysis revealed the presence of an unique cluster of Rhizopus polygalacturonase sequences that are separate from other fungal polygalacturonases. Conservation of 12 cysteines appears to be a special feature of this family of Rhizopus polygalacturonase sequences.
authors.affiliation: Biotechnology Research Institute, National Research Council Canada, 6100 Royalmount Avenue, Montreal, QC, Canada, H4P 2R2.
authors.forename: Zhizhuang
authors.initials: Z
authors.lastname: Xiao
authors.forename: Shaozhao
authors.initials: S
authors.lastname: Wang
authors.forename: Hélène
authors.initials: H
authors.lastname: Bergeron
authors.forename: Jianchun
authors.initials: J
authors.lastname: Zhang
authors.forename: Peter C K
authors.initials: PC
authors.lastname: Lau
mesh_terms: D003001:Cloning, Molecular; D019597:Flax / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D007218:Industrial Microbiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011096:Polygalacturonase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012233:Rhizopus / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D013784:Textiles / Q000382:microbiology*
chemical_list: D005656:Fungal Proteins; D011096:Polygalacturonase