Mouse Acidic Chitinase Effectively Degrades Random-Type Chitosan to Chitooligosaccharides of Variable Lengths under Stomach and Lung Tissue pH Conditions
Satoshi Wakita,
Yasusato Sugahara,
Masayuki Nakamura,
Syunsuke Kobayashi,
Kazuhisa Matsuda,
Chinatsu Takasaki,
Masahiro Kimura,
Yuta Kida,
Maiko Uehara,
Eri Tabata,
Koji Hiraoka,
Shiro Seki,
Vaclav Matoska,
Peter O. Bauer,
Fumitaka Oyama
Affiliations
Satoshi Wakita
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Yasusato Sugahara
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Masayuki Nakamura
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Syunsuke Kobayashi
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Kazuhisa Matsuda
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Chinatsu Takasaki
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Masahiro Kimura
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Yuta Kida
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Maiko Uehara
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Eri Tabata
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Koji Hiraoka
Department of Environmental Chemistry, Kogakuin University, Tokyo 192-0015, Japan
Shiro Seki
Department of Environmental Chemistry, Kogakuin University, Tokyo 192-0015, Japan
Vaclav Matoska
Laboratory of Molecular Diagnostics, Department of Clinical Biochemistry, Hematology and Immunology, Homolka Hospital, Roentgenova 37/2, 150 00 Prague, Czech Republic
Peter O. Bauer
Laboratory of Molecular Diagnostics, Department of Clinical Biochemistry, Hematology and Immunology, Homolka Hospital, Roentgenova 37/2, 150 00 Prague, Czech Republic
Fumitaka Oyama
Department of Chemistry and Life Science, Kogakuin University, Tokyo 192-0015, Japan
Chitooligosaccharides exhibit several biomedical activities, such as inflammation and tumorigenesis reduction in mammals. The mechanism of the chitooligosaccharides’ formation in vivo has been, however, poorly understood. Here we report that mouse acidic chitinase (Chia), which is widely expressed in mouse tissues, can produce chitooligosaccharides from deacetylated chitin (chitosan) at pH levels corresponding to stomach and lung tissues. Chia degraded chitin to produce N-acetyl-d-glucosamine (GlcNAc) dimers. The block-type chitosan (heterogenous deacetylation) is soluble at pH 2.0 (optimal condition for mouse Chia) and was degraded into chitooligosaccharides with various sizes ranging from di- to nonamers. The random-type chitosan (homogenous deacetylation) is soluble in water that enables us to examine its degradation at pH 2.0, 5.0, and 7.0. Incubation of these substrates with Chia resulted in the more efficient production of chitooligosaccharides with more variable sizes was from random-type chitosan than from the block-type form of the molecule. The data presented here indicate that Chia digests chitosan acquired by homogenous deacetylation of chitin in vitro and in vivo. The degradation products may then influence different physiological or pathological processes. Our results also suggest that bioactive chitooligosaccharides can be obtained conveniently using homogenously deacetylated chitosan and Chia for various biomedical applications.
