title: Cleavage action of a trypsin-like protease from Bacteroides gingivalis 381 on reduced egg-white lysozyme.
abstract: Soluble reduced lysozyme was extensively digested by a trypsin-like protease purified from the culture supernatant of the bacterium. The digestion peptides were separated and purified by reversed-phase high-performance liquid chromatography, and were subjected to amino acid analysis. The fragments were identified by their amino acid composition, and the cleavage sites in the lysozyme chain were determined. Like mammalian trypsin, the enzyme from B. gingivalis split peptide bonds non-specifically at carboxyl sides of internal arginine and lysine residues, but the lysine present at the amino terminus of the lysozyme chain was not released. In addition, the enzyme cleaved the peptide linkage at the amino side of lysine and bonds between leucine-glycine, alanine-leucine and leucine-serine. Thus the trypsin-like protease from B. gingivalis has some cleavage actions on lysozyme different from those of mammalian trypsin.
authors.affiliation: Department of Preventive Dentistry, School of Dentistry, University of Tokushima, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Endo
authors.forename: M
authors.initials: M
authors.lastname: Otsuka
authors.forename: E
authors.initials: E
authors.lastname: Ohara
authors.forename: M
authors.initials: M
authors.lastname: Sato
authors.forename: R
authors.initials: R
authors.lastname: Nakamura
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001439:Bacteroides / Q000201:enzymology*; D002851:Chromatography, High Pressure Liquid; D004529:Egg White; D006801:Humans; D007527:Isoenzymes / Q000302:isolation & purification / Q000494:pharmacology*; D008239:Lysine / Q000032:analysis; D009113:Muramidase / Q000378:metabolism*; D010514:Periodontal Pocket / Q000382:microbiology; D013045:Species Specificity; D014357:Trypsin / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000596:Amino Acids; D007527:Isoenzymes; D009113:Muramidase; D014357:Trypsin; D008239:Lysine