title: Biodegradation of shellfish wastes and production of chitosanases by a squid pen-assimilating bacterium, Acinetobacter calcoaceticus TKU024.
abstract: Two chitosanases (CHSA1 and CHSA2) were purified from the culture supernatant of Acinetobacter calcoaceticus TKU024 with squid pen as the sole carbon/nitrogen source. The molecular masses of CHSA1 and CHSA2 determined by SDS-PAGE were approximately 27 and 66 kDa, respectively. The optimum pH, optimum temperature, pH stability, and thermal stability of CHSA1 and CHSA2 were (pH 6, 50°C, pH 4-10, <90°C) and (pH 7, 60°C, pH 6-11, <70°C), respectively. CHSA1 and CHSA2 had broad pH and thermal stability. CHSA1 and CHSA2 were both inhibited by EDTA and were inhibited completely by 5 mM Mn(2+). CHSA1 and CHSA2 degraded chitosan with DD ranging from 60 to 98%, and also degraded some chitin. The most susceptible substrate was 60% deacetylated chitosan. Furthermore, TKU024 culture supernatant (1.5% SPP) incubated for 5 days has the most reducing sugars (0.63 mg/ml). With this method, we have shown that shellfish wastes may have a great potential for the production of bioactive materials.
authors.affiliation: Life Sciences Development Center, Tamkang University, Taipei, Taiwan. sabulo@mail.tku.edu.tw
authors.forename: San-Lang
authors.initials: SL
authors.lastname: Wang
authors.forename: Wan-Nine
authors.initials: WN
authors.lastname: Tseng
authors.forename: Tzu-Wen
authors.initials: TW
authors.lastname: Liang
mesh_terms: D016954:Acinetobacter calcoaceticus / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental; D049832:Decapodiformes / Q000382:microbiology*; D004795:Enzyme Stability; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D012758:Shellfish / Q000382:microbiology*; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D006026:Glycoside Hydrolases; C019868:chitosanase