title: Characterization of chitosanase of a deep biosphere Bacillus strain.
abstract: A chitosanase of deep-biosphere Bacillus thuringiensis strain JAM-GG01 was purified. The optimal pH and temperature for the purified enzyme (Cho-GG) were about pH 6 and 60 °C, but Cho-GG was unexpectedly unstable under incubation at over 40 °C. This discrepancy between higher activity and lower stability in the same range of temperature was abolished by the addition of reaction products, chitotriose and chitotetraose. The Cho-GG gene was amplified by PCR and sequenced. The deduced amino acid sequence of Cho-GG showed more than 98% identity to those of other Bacillus enzymes belonging to GH family 8. Although Cho-GG did not show the definite characteristics of a sub-seafloor ectoenzyme, the thermal stability of many chitosanases of B. turingienesis and other related strains can be improved by adding chitotriose or chitotetraose.
authors.affiliation: Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Japan. kobayahit@jamstec.go.jp
authors.forename: Tohru
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Osamu
authors.initials: O
authors.lastname: Koide
authors.forename: Shigeru
authors.initials: S
authors.lastname: Deguchi
authors.forename: Koki
authors.initials: K
authors.lastname: Horikoshi
mesh_terms: D000595:Amino Acid Sequence; D001413:Bacillus thuringiensis / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D004795:Enzyme Stability; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017423:Sequence Analysis, RNA; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D006026:Glycoside Hydrolases; C019868:chitosanase