Structural Characterization of Glucooligosaccharide Oxidase from Acremonium strictum
| العنوان: | Structural Characterization of Glucooligosaccharide Oxidase from Acremonium strictum |
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| المؤلفون: | Meng-Hwan Lee, Wen-Lin Lai, Shwu-Huey Liaw, Shuen-Fuh Lin, Cheng-Sheng Hsu, Ying-Chieh Tsai |
| المصدر: | Applied and Environmental Microbiology. 71:8881-8887 |
| بيانات النشر: | American Society for Microbiology, 2005. |
| سنة النشر: | 2005 |
| مصطلحات موضوعية: | Stereochemistry, Molecular Sequence Data, Flavoprotein, Flavin group, Applied Microbiology and Biotechnology, Pichia pastoris, chemistry.chemical_compound, Amino Acid Sequence, Cytokinin dehydrogenase, Enzymology and Protein Engineering, DNA Primers, Alanine, Flavin adenine dinucleotide, Base Sequence, Sequence Homology, Amino Acid, Ecology, biology, Acremonium strictum, biology.organism_classification, TATA Box, Peptide Fragments, Recombinant Proteins, Acremonium, Alcohol Oxidoreductases, Amino Acid Substitution, Biochemistry, chemistry, Spectrophotometry, biology.protein, Sequence Alignment, Food Science, Biotechnology, Cysteine |
| الوصف: | Glucooligosaccharide oxidase from Acremonium strictum was screened for potential applications in oligosaccharide acid production and carbohydrate detection. This protein is a unique covalent flavoenzyme which catalyzes the oxidation of a variety of carbohydrates with high selectivity for cello- and maltooligosaccharides. Kinetic measurements suggested that this enzyme possesses an open carbohydrate-binding groove, which is mainly composed of two glucosyl-binding subsites. The encoding gene was subsequently cloned, and one intron was detected in the genomic DNA. Large amounts of active enzymes were expressed in Pichia pastoris , with a yield of 300 mg per liter medium. The protein was predicted to share structural homology with plant cytokinin dehydrogenase and related flavoproteins that share a conserved flavin adenine dinucleotide (FAD)-binding domain. The closest sequence matches are those of plant berberine bridge enzyme-like proteins, particularly the characteristic flavinylation site. Unexpectedly, mutation of the putative FAD-attaching residue, H70, to alanine, serine, cysteine, and tyrosine did not abolish the covalent FAD linkage and had little effect on the K m . Instead, the variants displayed k cat values that were 50- to 600-fold lower, indicating that H70 is crucial for efficient redox catalysis, perhaps through modulation of the oxidative power of the flavin. |
| تدمد: | 1098-5336 0099-2240 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::28850264cbb5912300c7804cdc933624 https://doi.org/10.1128/aem.71.12.8881-8887.2005 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....28850264cbb5912300c7804cdc933624 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10985336 00992240 |
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