Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pyruvate, orthophosphate dikinase is a key enzyme in photosynthesis in some plants that exploit the C4 photosynthetic pathway for the fixation of CO2. The gene for this enzyme has been cloned and its primary structure has been analyzed. The sequence of the cloned genes spans about 12 kilobase pairs and consists of 19 exons. The site of initiation of transcription is located 211 nucleotides upstream from the first nucleotide of the initiation codon (position -211). Typical TATA and inverted CCAAT elements are present in the anticipated regions, as well as a sequence that is homologous to the binding site of Sp-1 protein (-51 to -42). Three long, direct-repeated sequences are present contiguously in the 5'-flanking region (-286 to -172), and two of the repeated sequences include sequences homologous to the core sequence of SV40 enhancer in the 3'-end portions. Southern blot analysis, coupled with mapping by analysis of restriction fragment length polymorphism, indicates that the gene for the enzyme involved in C4 photosynthesis is encoded by a single-copy gene and is located on chromosome 6. To test the promoter activity of the isolated gene, a chimeric gene composed of the 5'-flanking region of the gene and a structural gene for bacterial beta-glucuronidase was constructed and introduced into tobacco protoplasts by electroporation or used to transform tobacco plants by Agrobacterium-mediated transfer of the gene. In both cases, expression of the beta-glucuronidase gene was observed, indicating that the 5'-flanking region of the gene can act as a promoter in tobacco cells.
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PMID:Structure, genetic mapping, and expression of the gene for pyruvate, orthophosphate dikinase from maize. 217 Mar 54

The metabolic detoxication of bis(2-hydroxy-3, 5-dichlorophenyl)sulfoxide (BTS) in man was investigated. Bis(2-hydroxy-3, 5-dichlorophenyl)sulfide (BT) was identified in beta-glucuronidase treated urine following the administration of BTS by thin-layer chromatography, gas chromatography, ultraviolet spectrum and quantitative analysis. No other metabolites were detectable. BT-glucuronide was also identified in urine. It was assumed that BTS was reduced to BT and successively conjugated with glucuronide in man, and excreted as BT-glucuronide in the urine.
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PMID:Metabolic detoxication of bis-(2-hydroxy-3, 5-dichlorophenyl)-sulfoxide in man. 733 61

Pyruvate,orthophosphate dikinase (PPDK; EC 2.7.9.1) activity is abundant in leaves of C4 plants, while it is difficult to detect in leaves of C3 plants. Recent studies have indicated that C3 plants have a gene encoding PPDK, with a structure similar to that of PPDK in C4 plants. However, low expression makes PPDK detection difficult in C3 plants. This finding suggests that high PPDK expression in C4 plants is due to regulatory mechanisms which are not operative in C3 plants. We have introduced a chimeric gene consisting of the gene encoding beta-glucuronidase (GUS; EC 3.2.1.31) controlled by the PPDK promoter from a C4 plant, maize, into a C3 cereal, rice. The chimeric gene was exclusively expressed in photosynthetic organs, leaf blades and sheaths, and not in roots or stems. Histochemical analysis of GUS activity demonstrated high expression of the chimeric gene in photosynthetic organs, localized in mesophyll cells, and no or very low activity in other cells. GUS expression was also regulated by light in that it was low in etiolated leaves and was enhanced by illumination. These observations indicate that the mechanisms responsible for cell-specific and light-inducible regulation of PPDK observed in C4 plants are also present in C3 plants. We directly tested whether rice has DNA-binding protein(s) which interact with a previously identified cis-acting element of the C4-type gene. Gel retardation assays indicate the presence in rice of a protein which binds this element and is similar to a maize nuclear protein which binds PPDK in maize. Taken together, these results indicate that the regulatory system which controls PPDK expression in maize is not unique to C4 plants.
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PMID:Tissue-specific light-regulated expression directed by the promoter of a C4 gene, maize pyruvate,orthophosphate dikinase, in a C3 plant, rice. 841 45