Cyclodextrin Formation by the Thermostable a-Amylase of Thermoanaerobacterium thermosulfurigenes EM1 and Reclassification of the Enzyme as a Cyclodextrin Glycosyltransferase
نویسندگان
چکیده
glycosyltransferase. the enzyme as a cyclodextrin thermosulfurigenes EM1 and reclassification of alpha-amylase of Thermoanaerobacterium Cyclodextrin formation by the thermostable
منابع مشابه
Cyclodextrin formation by the thermostable alpha-amylase of Thermoanaerobacterium thermosulfurigenes EM1 and reclassification of the enzyme as a cyclodextrin glycosyltransferase.
Extensive characterization of the thermostable alpha-amylase of Clostridium thermosulfurogenes EM1, recently reclassified as Thermoanaerobacterium thermosulfurigenes, clearly demonstrated that the enzyme is a cyclodextrin glycosyltransferase (CGTase). Product analysis after incubation of the enzyme with starch revealed formation of alpha-, beta-, and gamma-cyclodextrins, as well as linear sugar...
متن کاملEngineering of cyclodextrin product specificity and pH optima of the thermostable cyclodextrin glycosyltransferase from Thermoanaerobacterium thermosulfurigenes EM1.
The product specificity and pH optimum of the thermostable cyclodextrin glycosyltransferase (CGTase) from Thermoanaerobacterium thermosulfurigenes EM1 was engineered using a combination of x-ray crystallography and site-directed mutagenesis. Previously, a crystal soaking experiment with the Bacillus circulans strain 251 beta-CGTase had revealed a maltononaose inhibitor bound to the enzyme in an...
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The crystal structure of the cyclodextrin glycosyltransferase (CGTase) from the thermophilic microorganism Thermoanaerobacterium thermosulfurigenes EM1 has been elucidated at 2.3 A resolution. The final model consists of all 683 amino acid residues, two calcium ions and 343 water molecules, and has a crystallographic R-factor of 17.9% (Rfree 24.9%) with excellent stereochemistry. The overall fo...
متن کاملImproved thermostability of bacillus circulans cyclodextrin glycosyltransferase by the introduction of a salt bridge.
Cyclodextrin glycosyltransferase (CGTase) catalyzes the formation of cyclodextrins from starch. Among the CGTases with known three-dimensional structure, Thermoanaerobacterium thermosulfurigenes CGTase has the highest thermostability. By replacing amino acid residues in the B-domain of Bacillus circulans CGTase with those from T. thermosulfurigenes CGTase, we identified a B. circulans CGTase mu...
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Bacillus licheniformis RM44 was isolated from hot spring near Karachi and screened forthe production of extracellular amylase Amy RM44. Amy RM44 was purified to homogeneityon a single step by affinity chromatography using insoluble corn starch. The molecular weightof Amy RM44 was estimated to be 66 kDa by SDS–PAGE and zymographic analysis. Nine foldpurification was achieved with the specific ac...
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