Characterization of Cyclodextrin Glucanotransferase Produced by Bacillus megaterium

Abstract

Cyclodextrin glucanotransferase, produced by Bacillus megaterium, was characterized, and the biochemical properties of the purified enzyme were determined. The substrate specificity of the enzyme was tested with different alpha-1,4-glucans. Cyclodextrin glucanotransferase displayed maximum activity in the case of soluble starch, with a Km value of 3.4 g/L. The optimal pH and temperature values for the cyclization reaction were 7.2 and 60 degrees C, respectively. The enzyme was stable at pH 6.0-10.5 and 30 degrees C. The enzyme activity was activated by Sr2+, Mg2+, Co2+, Mn2+, and Cu2+, and it was inhibited by Zn2+ and Ag+. The molecular mass of cyclodextrin glucanotransferase was established to be 73,400 Da by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, 68,200 Da by gel chromatography, and 75,000 Da by mass spectrometry. The monomer form of the enzyme was confirmed by the analysis of the N-terminal amino acid sequence. Cyclodextrin glucanotransferase formed all three types of cyclodextrins, but the predominant product was beta-cyclodextrin.

Hydrodynamics and mass transfer coefficients of airlift reactors with net draft tubes of different sizes: Production of cyclodextrin glucanotransferase using Bacillus sp. DSM 2523

“…). The amount of enzyme synthesized by the test microorganism in the present study was in the production range reported in the literature (Table ) . In the present study excessive foaming was observed in the test ALR–NDTs and by use of low gas flow rate and antifoam reagent the test system was controlled.…”

Effect of substrate concentration and temperature on the kinetics and thermal stability of cyclodextrin glycosyltransferase for the production of β-cyclodextrin: Experimental results vs. mathematical model

“…Gawande and Patkar [12] reported that the temperature stability of the enzyme was improved in the presence of a substrate at 40 • C. It is possible that CGTase could maintain their active structure at high temperature by binding with substrate. Kim et al [20] and Pishtiyski et al [21] also found that the stability of CGTase increased with the presence of starch. This phenomenon is due to the adsorption of CGTase on the starch surface that protects the enzyme against denaturation [22].…”

Engineering of cyclodextrin glucanotransferases and the impact for biotechnological applications

“…I-5β(Shim et al 2004) Anaerobranca gottschalkii α(Thiemann et al 2004) Bacillus circulans 8β(Nitschke et al 1990) Bacillus circulans 251β(Lawson et al 1994) Bacillus circulans A11β(Rimphanitchayakit et al 2005) Bacillus circulans DF 9Rα/β(Marechal et al 1996) Bacillus clarkii 7384γ(Takada et al 2003) Bacillus clausii E16 a β(Alves-Prado et al 2008) Bacillus firmus 290-3β/γ(Englbrecht et al 1988) Bacillus firmus 7B a β(Moriwaki et al 2007) Bacillus firmus NCIM 5119 a β(Gawande et al 1999) Bacillus firmus no. 37 a β(Matioli et al 2001) Bacillus licheniformis α/β(Hill et al 1990) Bacillus macerans b α(Takano et al 1986) Bacillus megaterium a β(Pishtiyski et al 2008) Bacillus obhensis β(Sin et al 1991) Bacillus sp. B1018β(Itkor et al 1990) Bacillus sp.…”