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N. J. King 《The Biochemical journal》1966,100(3):784-792
1. The extracellular enzymes present in the culture filtrates of Coniophora cerebella grown on various carbohydrate carbon sources were investigated. Enzymes that degraded cellulose derivatives, hemicellulose fractions, starch, laminarin, pectin and several oligosaccharides were detected. 2. All the polysaccharide-degrading activities were adaptive except for that acting on laminarin. 3. The culture filtrates degraded native cellulose to only a very limited extent. 4. The hemicellulase activity included enzymes acting on all the major components of wood hemicellulose. 5. The main starch-degrading enzyme was a glucoamylase. 6. Laminarin-degrading activity was produced when cellulose, hemicellulose or starch was used as carbon source for the fungus and it may be involved in the re-utilization of hyphal carbon or of a reserve polysaccharide synthesized during active growth of the organism. 相似文献
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The metabolism of [2-14C]indole in the rat 总被引:3,自引:1,他引:2
1. [2-14C]Indole has been synthesized from [14C]formate and o-toluidine via N[14C]-formyltoluidine. 2. When fed to rats, the 14C of [14C]indole (dose 70–80mg./kg. body wt.) is fairly rapidly excreted, and in 2 days an average of 81% appears in the urine, 11% in the faeces and 2·4% as carbon dioxide in the expired air. 3. Radioactivity is excreted in the urine as indoxyl sulphate (50% of the dose), indoxyl glucuronide (11%), oxindole (1·4%), isatin (5·8%), 5-hydroxyoxindole conjugates (3·1%), N-formylanthranilic acid (0·5%) and unchanged indole (0·07%). The faeces contain indoxyl sulphate (0·4% of the dose) and indole (0·2%), but the major metabolites have not been identified. 4. Fed to rats with biliary cannulae an average of 5·6% of a dose of [14C]indole (20–60mg./kg. body wt.) is excreted in the bile in 2 days. Radioactivity is present as indoxyl sulphate (0·8% dose) and 5-hydroxyoxindole conjugates (0·6%). 5. Rats further metabolize indoxyl into N-formylanthranilic acid and anthranilic acid, and oxindole into 5-hydroxyoxindole. 6. With rat-liver microsomes plus supernatant under aerobic conditions, indole gives indoxyl, oxindole, possibly isatin, N-formylanthranilic acid and anthranilic acid, but under anaerobic conditions gives only oxindole. Similarly, under aerobic conditions, oxindole gives 5-hydroxyoxindole, anthranilic acid and o-aminophenylacetic acid. 7. Indole is metabolized by two pathways, one via indoxyl to isatin, N-formylanthranilic acid and anthranilic acid, and the other via oxindole to 5-hydroxyoxindole and possibly to o-aminophenylacetic and anthranilic acid. 8. The following new compounds are described: 4-hydroxy-2-nitrophenylacetic acid, 3-, 4- and 5-benzyloxy-2-nitrophenylacetic acid, 5- and 7-hydroxyoxindole and 5-aminoacridine indoxyl sulphate. 相似文献
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