title: Inhibitory analysis of the effect of polycyclic aromatic hydrocarbons on the activity of chitinase by means of liquid chromatography-mass spectrometry of chitin oligosaccharides.
abstract: The analytical method of determining enzyme activity by liquid chromatography-mass spectrometry (LC/MS) was developed and applied for investigation of the effect of polycyclic aromatic hydrocarbons (PAHs) on the enzyme activity of chitinase. The measurement of chitinase activity by LC/MS is useful in order to use the nonderivatized substrate, which can show in vivo chitinase activity. Substrate consumption and product formation were monitored in order to determine chitinase activity. It was shown that, for the first time, in vitro addition of PAHs inhibited the activity of chitinase in a noncompetitive manner. The IC(50) value of benzo[a]pyrene was 1.4 microM, and PAHs containing four or more aromatic rings showed the same or higher inhibitory effect, whereas PAHs with a lower number of aromatic rings showed lower inhibition of the chitinase activity than benzo[a]pyrene.
authors.affiliation: Department of Chemistry, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo 192-0397, Japan. sbwjh246@ybb.ne.jp
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Ooki
authors.forename: Momoko
authors.initials: M
authors.lastname: Kumemura
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Itoh
authors.forename: Takashi
authors.initials: T
authors.lastname: Korenaga
mesh_terms: D002686:Chitin / Q000737:chemistry / Q000378:metabolism*; D002688:Chitinases / Q000037:antagonists & inhibitors*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism*; D011083:Polycyclic Compounds / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D009844:Oligosaccharides; D011083:Polycyclic Compounds; D002686:Chitin; D002688:Chitinases