Characterization of 38kDa and 42kDa chitinase isozymes from the liver of Japanese common squid Todarodes pacificus.

• MATSUMIYA MASAHIRO

  Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University

• MIYAUCHI KOUJI

  Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University

• MOCHIZUKI ATSUSHI

  Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University

Bibliographic Information

Other Title

• Characterization of 38kDa and 42kDa chitinase isozymes from the liver of Japanese squid Todarodes pacificus

Abstract

Characterization was investigated on the 38 kDa and 42 kDa chitinase (EC3.2.1.14) isozymes from the liver of Japanese common squid Todarodes pacificus. Optimum pH toward colloidal chitin was observed at pH 3.0 for the 38 kDa chitinase, and pH 3.0 and 9.0 for the 42 kDa chitinase. K_m and k_cat of the 38 kDa and 42 kDa chitinases toward a longer substrate, glycol chitin, were 0.071 mg/mL and 1.22/s, and 0.074 mg/mL and 0.196/s, respectively. Alternatively, strong substrate inhibition of both chitinases were observed toward a short substrate, N-acetylchitopentaose (GlcNAc₅). Both chitinases decomposed not only chitin but also chitosan (D. A. 95%). The cleavage pattern and reaction rate were investigated using N-acetylchitooligosaccharides (GlcNAc_n, n=2-6). Both chitinases hydrolyzed GlcNAc_n (n=4, 5, and 6). The release of GlcNAc was not observed. The speed of the reaction was observed to be in the following order: GlcNAc₄>GlcNAc₅>GlcNAc₆ for the 38 kDa chitinase, and GlcNAc₆>GlcNAc₅>GlcNAc₄ for the 42 kDa chitinase. Both the chitinases released p-nitrophenol from p-nitrophenyl GlcNAc_n (n2, 3, and 4). N-terminal amino acid sequences of the 38 kDa and 42 kDa chitinases were YLLSXYFTNWSQYRPGAGKYFPQNI and EYRKVXYYTNWSQYREVPAKFFPEN, respectively.

Journal

• Fisheries science

  Fisheries science 68 (3), 603-609, 2002

  The Japanese Society of Fisheries Science

Keywords

• amino acid sequence
• characterization
• chitinase
• Japanese common squid
• kinetics
• liver
• substrate specificity
• Todarodes pacificus

Details

• CRID: 1390282679405539072
• NII Article ID: 130003903661
• NII Article ID: 10008558145
• NII Book ID: AA10993718
• DOI: 10.1046/j.1444-2906.2002.00467.x
• COI: 1:CAS:528:DC%2BD38Xlt1Wit7o%3D
• ISSN: 14442906
• ISSN: 09199268
• NDL BIB ID: 6194901
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6194901
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed