Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D02011 (FAD)
 5,530 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was to develop radiofluorinated ethyluracil (FEU) and deoxyadenosine analogues (FAD) for noninvasive assessment of tumor proliferative potential by positron emission tomography (PET). 5-(2-Fluoroethyl)uracil ([18F]FEU) was prepared by treating 2,4-dimethoxy-5-(2-hydroxyethyl)pyrimidine with K18F, followed by hydrolysis with HBr. Fluorodeoxyadenosine ([18F]FAD) was prepared by treating a triacetylated analogue of adenosine with K18F. In vitro cell proliferation assay of [18F]-FEU was performed using human peripheral blood mononucleus cells. Tissue distributions were studied in breast tumor-bearing rats at 0.5, 1, 2 and 4 h along with autoradiography at 45 min postinjection. PET imaging studies were conducted in VX-2 tumor-bearing rabbits. In vitro assay indicated that [18F]FEU incorporated into DNA/RNA during cell proliferation. Tumor-to-tissue count density ratios of [18F]FAD and [18F]-FEU increased as a function of time. [18F]FAD had higher tumor-to-nontumor tissue count density ratios than [18F]FEU. Autoradiograms of [18F]FEU and [18F]FAD, and PET images of [18F]FEU, showed that the tumors could be well visualized. The results suggest that [18F]FEU and [18F]FAD have potential use in evaluating tumor cell proliferation by PET.
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PMID:Assessment of tumor cell proliferation using [18F]fluorodeoxyadenosine and[18F]fluoroethyluracil. 869 41

In order to engineer the choline oxidase from Arthrobacter nicotianae (An_CodA) for the potential application as biological bleach in detergents, the specific activity of the enzyme toward the synthetic substrate tris-(2-hydroxyethyl)-methylammonium methylsulfate (MTEA) was improved by methods of directed evolution and rational design. The best mutants (up to 520% wt-activity with MTEA) revealed mutations in the FAD- (A21V, G62D, I69V) and substrate-binding site (S348L, V349L, F351Y). In a separate screening of a library comprising of randomly mutagenised An_CodA, with the natural substrate choline, four mutations were identified, which were further combined in one clone. The constructed clone showed improved activity towards both substrates, MTEA and choline. Mapping these mutation sites onto the structural model of An_CodA revealed that Phe351 is positioned right in the active site of An_CodA and very likely interacts with the bound substrate. Ala21 is part of an alpha-helix which interacts with the diphosphate moiety of the flavin cofactor and might influence the activity and specificity of the enzyme.
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PMID:Engineering of choline oxidase from Arthrobacter nicotianae for potential use as biological bleach in detergents. 2046 37