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Bacillus macerans Cyclodextrins

Rha, CS, DH Lee, SG Kim, WK Min, SG Byun, DH Kweon, NS Han and JH Seo (2005). Production of cyclodextrin by poly-lysine fused Bacillus macerans cyclodextrin glycosyltransferase immobilized on cation exchanger. Journal of Molecular Catalyci B ... [Pg.80]

Takano, T., Fukuda, M., Monma, M., Kobayashi, S., Kainuma, K., Yamane, K. Molecular cloning, DNA nucleotide sequencing and expression in Bac/// 5 subtilis cells of Bacillus macerans cyclodextrin glucanotransferase gene. Journal of Bacteriology 1986, 166(3), 1118-1122. [Pg.158]

The reason that the cyclodextrin transglycosylase occurs only in Bacillus macerans and a few other thermophilic bacteria has not, as yet, been determined. Nevertheless, it is interesting to speculate about the possible evolutionary advantage that a bacterium might have by possessing the cyclodextrin transglycosylase. Because the cyclodextrins have no end... [Pg.207]

Prior to 1939, however, it was not known whether the cyclodextrins were products of the synthetic metabolism of Bacillus macerans, and therefore, perhaps, quite different from the components of starch, or whether they were formed by a single enzyme and therefore closely related to the starch structure. Then, Tilden and Hudson announced the discovery of a cell-free enzyme preparation from cultures of Bacillus macerans which had the ability to convert starch into the Schardinger dextrins without the production of maltose, glucose, or any other reducing sugars. They thus concluded that the Schardinger dextrins were either the true components of starch or closely related to such true components. [Pg.215]

Thus, Freudenberg concluded that the cyclodextrins are not preformed in starch, but that their formation is made possible by the helicity of the starch chain. Freudenberg s hypotheses concerning the starch structure (that is, the amylose fraction) and the Bacillus macerans amylase mechanism have been confirmed by X-ray crystallography and chromatographic techniques. ... [Pg.217]

Cyclodextrins, products of the degradation of starch by an amylase of Bacillus macerans(1), have been studied in terms of chemical modifications, mainly for the purpose of developing efficient enzyme mimics(2). Not only their unique cyclic structures, but also their ability to form Inclusion complexes with suitable organic molecules, led us to Investigate the total synthesis of this class of molecules(3) We describe here an approach to a total synthesis of alpha(l), gamma(2), and "iso-alpha" cyclodextrin (3). [Pg.150]

In 2002, Do et al. [85] proposed a pathway for the enzymatic synthesis of (-)-menthyl a-maltoside and a-maltooligosides from (-)-menthyl a-glucoside using cyclodextrin glucanotransferase obtained from Bacillus macerans. The reaction can be performed in a reactor containing (-)-menthyl a-glucoside, the enzyme and soluble starch the yield was about 80% 15% (-)-menthyl a-malto-side and 65% (-)-menthyl a-maltooligosides, respectively. Treatment of the starch with a-amylase can raise the proportion of (-)-menthyl a-maltoside. [Pg.501]

Cyclodextrins are doughnut-shaped, macrocyclic oligosaccharides constructed of glucose units linked by a a(l - 4) bond. Hexamer, heptamer, and octamer are the most common, often called the a-, / -, and y-cyclodextrins, respectively (Fig. 1). Although cyclodextrin has been known as one of the oligoglucoses produced by Bacillus macerans since 1891 (2), its spectacular behavior as the possible enzyme model was first observed by Cramer and his co-worker (J). [Pg.418]

Some transferases can directly use and transform oligosaccharides as donors without further activation. The following paragraph will discuss some reactions with non-Leloir glycosyltransferases which are performed on a preparative level. For example, cyclodextrin-al-4-glucosyltransferase (CGT) from Klebsiella pneumonia or from Bacillus macerans are rather versatile enzymes which can catalyze various reactions. [Pg.38]

Further, various glycosyl fluorides were tested as substrates for CGT [83]. This approach gave novel insights into the specificity of the catalytic site of CGT from Bacillus macerans and new routes for the preparation of regioselectively modified cyclodextrins. [Pg.39]

They are prepared by enz3miatic degradation of starch. The enzyme cyclodextrin glucanosyltransferase (CGT) from Bacillus macerans. Bacillus megaterium or other bacterial strains cut the starch helix and join both ends of such destruct forming a cyclic compound. Because enzymes are not very specific, the obtained mixture contains cyclodextrins from 6 to 12 glucose units. The main fi-actions are a-, p- and y-cyclodextrins which correspond to 6, 7 and 8 glucose units. [Pg.365]

Structure and stoichiometry. Cyclodextrins (CyDs) were discovered over 100 years ago by Villiers.23 They are formed by Bacillus macerans, which is a type of bacteria that degrades starch,24 using the enzyme cyclomaltodextrin gluconotransferase, or CyD glycosyl transferase.25 CyDs were often called Schardinger dextrins because they were first popularized by Schardinger.26... [Pg.218]

Cyclodextrins are degradation products from starch by the bacterium Bacillus macerans. They are separated by precipitation with complexing agents and purified by recrystallization. They could probably be produced industrially by the tonne. The formation of cyclodextrins is interpreted as a trans glycosidation of amylose under enzymic control. The latter, in aqueous solution, adopts at least partially the shape of a helix with a period of six glucopyranose units. The bacterial enzyme catalyses the junction of two glucopyranose residues separated... [Pg.102]

Cyclodextrins (see Chap. 5) can be prepared in one step from starch using a recombinant enzyme based on a thermophilic bacterium, a species of Thermoanaerobacter,254 Cyclodextrin glucanotransferase from Bacillus macerans and other organisms can also be used.255... [Pg.259]

Several methods can be used for separation. A current favorite is to use a series of compounds called cyclodextrins, which have been found to associate preferentially with one form of optical isomer more than the other. Figure 31-9 shows a diagram of alpha cyclodextrin. They are obtained by the action of Bacillus macerans amylase on starch to form homogeneous cyclic alpha- 1,4-D-glucopyranose units. Alpha is the hexa ring, beta is the... [Pg.366]

Cyclodextrins, also called Schardinger dextrins, cycloamyloses, or cyclo-glucans, are a family of cyclic oligosaccharides obtained from starch and related compounds by the action of the amylase of Bacillus macerans. They were discovered by Villiers in 1891 [10] and the first detailed description of their properties and isolation was made by Schardinger in 1903 [11-13]. [Pg.3]

Arya, SK and SK Srivastava (2006). Kinetics of immobilized cyclodextrin glucanotrans-ferase produced by Bacillus macerans KPCC 8244. Enzyme and Microbial Technology, 39, 507-510. [Pg.81]

Kobayashi, S, K Kainuma and S Suzuki (1978). Purification and some properties of Bacillus macerans cycloamylose (cyclodextrin) glucanotransferase. Carbohydrate... [Pg.97]

Qi, Q, X She, T Endo and W Zimmermann (2004). Effect of the reaction temperature on the transglycosylation reactions catalyzed by the cyclodextrin glucanotransferase from Bacillus macerans for the synthesis of large-ring cyclodextrins. Tetrahedron, 60,... [Pg.98]

Cyclodoxtrins (cycloamyloses, cycloglucans after their discoverer also Schardinger dextrins). Cyclic dextrins are formed on degradation of starch by Bacillus macerans or B. circulans under the action of cyclodextrin glycosyltransferase. The C. consist of 6,7,... [Pg.165]


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