Isolation of alkalophilic CGTase-producing bacteria and characterization of cyclodextrin-glycosyltransferase

Brazilian Archives of Biology and Technology

Lma Hiroko Higuti²  Simone Wichert Grande¹  Roberta Sacco¹  Aguinaldo José Do Nascimento¹ 

[1] ,Universidade Federal do Paraná Setor de Ciências Biológicas Departamento de Patologia BásicaCuritiba PR ,Brazil

关键词: Cyclodextrin glycosyltransferase;    Bacillus firmus;    characterization;   

DOI  :  10.1590/S1516-89132003000200007

来源: SciELO

【 摘 要 】

One hundred and twenty five soil samples were collected from the regions of roots of corn, cassava, potato, bean, sugar cane, soya, and pumpkin. From these, 75 strains were isolated that produced a yellowish halo surrounding the colonies, due to a phenolphtalein-cyclodextrin (CD) complex, and these were selected as alkalophilic CGTase-producing bacteria. All the 75 strains were identified as Bacillus firmus by microscopy and biochemical tests. The activity of the CGTase's varied from 2² to 2(10) dilutions,when assayed by CD-trichloroethylene (TCE)-complex precipitation. Strain 31 that produced the enzyme at the higher level was selected, and its enzyme was partially purified by starch adsorption (x 17) in a yield of 51%. Maximum enzyme activity occurred at pH 5.5 and 8.5. At pH 5.5, the optimum temperature was 60°C. On increased from 30°C to 85°C, the thermodynamic parameter for activation energy was 8.27 kcal.mol-1. The enzyme was inhibited by Ca2+, Mg2+, Fe2+, Cu2+, Mn2+, and Zn2+.

【 授权许可】

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