The gene encoding the cyclodextrin glycosyltransferase (CGTase) of Paenibacillus pabuli US132, previously described as efficient antistaling agent and good candidate for cyclodextrins production, was cloned, sequenced, and expressed in Escherichia coli. Sequence analysis showed that the mature enzyme (684 amino acids) was preceded by a signal peptide of 34 residues. The enzyme exhibited the highest identity (94%) to the beta-CGTase of Bacillus circulans no. 8. The production of the recombinant CGTase, as active form, was very low (about 1 U/mL) in shake flasks at 37 degrees C. This production reached 22 U/mL after 22 hours of induction by mainly shifting the postinduction temperature from 37 to 19 degrees C and using 2TY instead of LB medium. High enzyme production (35 U/mL) was attained after 18 hours of induction in fermentor using the same culture conditions as in shake flask. The recombinant enzyme showed V(max) and K(m) values of 253 +/- 36 mumol of beta-cyclodextrin/mg/min and 0.36 +/- 0.18 g/L, respectively.
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http://dx.doi.org/10.1155/2008/692573 | DOI Listing |
Front Microbiol
November 2024
State Key Laboratory of Biobased Material and Green Papermaking (LBMP), Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, China.
Sci Rep
December 2024
National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
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View Article and Find Full Text PDFInt J Biol Macromol
November 2024
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu 214122, China. Electronic address:
Carbohydr Polym
December 2024
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, People's Republic of China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi, Jiangsu 214122, People's Republic of China. Electronic address:
γ-Cyclodextrin (γ-CD) is an attractive material among the natural cyclodextrins owing to its excellent properties. γ-CD is primarily produced from starch by γ-cyclodextrin glycosyltransferase (γ-CGTase) in a controlled system. However, difficulty in separation and low conversion rate leads to high production costs for γ-CD.
View Article and Find Full Text PDFInt J Biol Macromol
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Key Laboratory of Synergetic and Biological Colloids, Ministry of Education, Wuxi 214122, Jiangsu Province, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China; Institute of Future Food Technology, JITRI, Yixing 214200, Jiangsu Province, China. Electronic address:
Actinomyces viscous (A. viscous) is well documented as a major cariogenic bacterium in the oral cavity and needs to be inhibited and removed timely. Essential oils (EOs) are recognized as secure antibacterial agents for treating oral diseases, but their volatility and insolubility limit their application.
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