Production and purification of CGTase of alkalophylic Bacillus isolated from Brazilian soil

• Published in: Applied biochemistry and biotechnology 1998, Vol.70, p.267-275
• Main Authors: Matioli, G. (State University of Maringa, Maringa, PR, Brazil.), Zanin, G.M, Guimaraes, M.F, Moraes, F.F. de
• Format: Article
• Language: English
• Subjects: BACILLUS; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; BRASIL; BRAZIL; BRESIL; Fundamental and applied biological sciences. Psychology; Isolation and description; Mission oriented research; PURIFICACION; PURIFICATION; SOIL; SOL; SUELO; TRANSFERASAS; TRANSFERASE; TRANSFERASES
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/BF02920143

Alkalophylic bacilli that produce cyclodextringlycosyltransferase (CGTase) were isolated from Brazilian soil, with a scheme of two plating steps. In the first step, the bacterial isolate forms a halo in the cultivation medium that contains gamma-cyclodextrin (CD) complexing dyes. The CGTase of an isolate was purified 157-fold by biospecific affinity chromatography, with beta-CD showing a mol wt of 77,580 Daltons. It produces a gamma- to beta-CD ratio of 0.156 and a small amount of alpha-CD, using maltodextrin 10% as substrate, at 50 degrees C, pH 8.0 and 22 h reaction time, reaching 21.4% conversion of the substrate to cyclodextrins. In the second screening step, the isolates chosen give larger halos with beta-CD complexing dyes, and smaller halos with beta-CD complexing dyes, leading to a 30% improvement in gamma-CD selectivity, although at lower total yield for cyclodextrins (11.5%)