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1.
Allantoinase and allantoicase are known to form a complex in amphibian liver. In this study, a new type of allantoinase that did not form a complex with allantoicase was found in the amphibian liver. Purified enzyme had a molecular mass of about 44 kDa both in SDS-PAGE and gel-filtrations. The enzyme cross-reacted with anti-sardine allantoinase polyclonal antibody, and it weakly cross-reacted with anti-bullfrog allantoinase polyclonal antibody.  相似文献   

2.
Allantoinase and allantoicase are located in the same protein molecule in amphibian liver, whereas the two enzymes are different proteins in marine fish and invertebrate liver (Takada, Y., and Noguchi, T. (1983) J. Biol. Chem. 258, 4762-4764). The amphibian enzyme was rapidly purified from frog liver by using its following characteristics. 1) The enzyme binds to the intracellular membranes in the hypotonic solution. 2) The membrane-bound enzyme is not solubilized by the detergent. 3) The membrane-bound enzyme is solubilized by oxaloacetate. The electrophoresis of the purified enzyme gave a single protein band in the absence of sodium dodecyl sulfate, and gave two protein bands with molecular weights of 48,000 and 54,000, respectively, in the presence of sodium dodecyl sulfate. With a specific antibody raised against each subunit, allantoinase activity was found to be from the large subunit, and allantoicase activity to be from the small subunit. This amphibian allantoinase and allantoicase complex was compared with allantoinase and allantoicase purified from fish liver. Fish allantoinase was a single peptide and fish allantoicase was composed of two identical subunits. Fish allantoinase had an identical molecular weight with amphibian large (allantoinase) subunit and the subunit of fish allantoicase with amphibian small (allantoicase) subunit. These results suggest that the evolution of fish to amphibian resulted in the dissociation of allantoicase into subunits and in the association of allantoinase with allantoicase. The two enzymes are lost by further evolution.  相似文献   

3.
The end product of purine metabolism varies from species to species. The degradation of purines to urate is common to all animal species, but the degradation of urate is much less complete in higher animals. The comparison of subcellular distribution, intraperoxisomal localization forms, molecular structures, and some other properties of urate-degrading enzymes (urate oxidase, allantoinase, and allantoicase) among animals is described. Liver urate oxidase (uricase) is located in the peroxisomes in all animals with urate oxidase. On the basis of the comparison of intraperoxisomal localization forms, mol wt, and solubility of liver urate oxidase among animals, it is suggested that amphibian urate oxidase is a transition form in the evolution of aquatic animals to land animals. Allantoinase and allantoicase are different proteins in fish liver, but the two enzymes form a complex in amphibian liver. The subcellular localization of allantoinase and allantoicase varies among fishes. Hepatic allantoinase is located both in the peroxisomes and in the cytosol in saltwater fishes, and only in the cytosol in freshwater fishes. Hepatic allantoicase is located on the outer surface of the, peroxisomal membrane in the mackerel group and in the peroxisomal matrix in the sardine group. Amphibian hepatic allantoinase-allantoicase complex is probably located in the mitochondria. On the basis of previous data, changes of allantoinase and allantoicase in molecular structure and intracellular localization during animal evolution may be as follows: Fish liver allantoinase is a single peptide with a mol wt of 54,000, and is located both in the peroxisomes and in the cytosol, or only in the cytosol. Fish liver allantoicase consists of two identical subunits with a mol wt of 48,000, and is located in the peroxisomal matrix or on the outer surface of the peroxisomal membrane. The evolution of fishes to amphibia resulted in the dissociation of allantoicase into subunits, and in the association of allantoinase with the subunit of allantoicase. This amphibian enzyme was lost by further evolution.  相似文献   

4.
Urate-degrading enzymes such as uricase, allantoinase, and allantoicase are located in the peroxisomes of marine fish liver (Noguchi, T., Takada, Y., and Fujiwara, S. (1979) J. Biol. Chem. 254, 5272-5275). On the basis of intraperoxisomal localization of hepatic allantoicase, 13 different fishes were classified into two groups: mackerel group and sardine group. Allantoicase is located on the outer surface of the peroxisomal membrane in the mackerel group and in the peroxisomal soluble matrix in the sardine group. The peroxisomal membrane enzyme and the peroxisomal matrix enzyme are not distinguishable on the basis of the number and molecular weight of the subunits, but differ in isoelectric point and electrophoretic mobility. The molecular weight of the fish allantoicase subunit is identical with that of the small subunit (allantoicase subunit) of amphibian allantoinase-allantoicase complex, suggesting that the subunit of fish allantoicase changed to the small subunit of the amphibian complex during evolution: allantoinase and allantoicase are present as a complex in amphibian liver (Noguchi, T., Fujiwara, S., and Hayashi, S. (1986) J. Biol. Chem. 261, 4221-4223).  相似文献   

5.
The distribution of enzymes involved in purine degradation in fish and crustaceous liver was examined by centrifugation in a sucrose density gradient. In mackerel, yellow mackerel, and prawn liver and mantis club hepatopancreas, uricase and allantoinase were located only in the peroxisomes and in the soluble fraction from broken peroxisomes, and allantoicase was located only in the peroxisomes. Uricase and allantoinase seem to be located in the peroxisomal matrix and allantoicase in the peroxisomal membrane. Adenase, guanase, and xanthine oxidase were present only in the soluble fraction of mackerel liver.  相似文献   

6.
7.
Summary Carp liver was fractionated by differential and density gradient centrifugation and assayed for enzymes of purine catabolism. While urate oxidase is an excusively peroxisomal enzyme, only a very small percentage of the enzymes xanthine oxidase, allantoinase and allantoicase is associated with subcellular or ganelle fractions. There is no general purine catabolizing subcellular compartment.There is some but not yet conclusive evidence for the assumption that urate oxidase is a membrane bound enzyme.  相似文献   

8.
9.
《Experimental mycology》1990,14(3):243-254
The regulation of nitrogen metabolism pathways was examined inPhanerochaete chrysosporium in relation to the repression of lignin peroxidase by nitrogen or carbon in this fungus. Under conditions of nitrogen derepression,P. chrysosporium synthesizes the amidohydrolases, formamidase (EC 3.5.1.9) and acetamidase (EC 3.5.1.4) and the enzymes of purine catabolism uricase (EC 1.7.3.3), allantoinase (EC 3.5.2.5), and allantoicase (EC 3.5.3.4). Formamidase is repressed to low levels in the presence of ammonium and there is no apparent control of this enzyme by carbon catabolite repression. Although formamide is a nitrogen source, it is not a carbon source forP. chrysosporium. Glutamate totally represses formamidase. Uricase, allantoinase, and allantoicase are also regulated by nitrogen repression but not carbon catabolite repression. Urease is synthesized at similar levels irrespective of the nitrogen or carbon conditions. The sensitivity of uricase, allantoinase, and allantoicase to nitrogen repression is less than that of formamidase. In contrast to formamidase, glutamate is not a more powerful repressor of uricase, allantoinase, and allantoicase compared with ammonium. No pathway-specific induction is required for the synthesis of formamidase, uricase, allantoinase, and allantoicase. Altogether these features indicate that nitrogen metabolism inP. chrysosporium is similar to that inAspergillus nidulans in its regulation, despite the absence of pathway-specific induction of the enzymes examined. These results are consistent with the existence of a regulatory gene mediating nitrogen catabolite repression similar to theA. nidulans areA gene inP. chrysosporium. Although glycerol acts as a nonrepressive carbon source for lignin peroxidase production (except when used at high concentrations), glutamate totally represses lignin peroxidase even in cultures with glycerol. This indicates that carbon regulation and nitrogen regulation of lignin peroxidase may not be separated inP. chrysosporium.  相似文献   

10.
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12.
Hyphomicrobium species are able to use allantoin as a nitrogen source for growth. Allantoin is broken down to glyoxylate and ammonia by the consecutive action of allantoinase, allantoicase, ureidoglycolase and urease.  相似文献   

13.
Abstract. Water stress created by withholding irrigation in mung bean resulted in decreased leaf water potential and nodule moisture content. Decreased leaf water potential was associated with decreased activity of nitrogenase, glutamine synthetase (GS), asparagine synthetase (AS), aspartate amino transferase (AAT), xanthine dehydrogenase (XDH) and uricase. However, the activity of glutamate dehydrogenase increased three-fold under severe stress. The activity of allantoinase and allantoicase was not affected by moderate stress but decreased under severe stress. The in vitro production of allantoic acid from allantoin and uric acid in the cytosol fraction decreased more than its production from xanthine and hypoxanthine. The production of NADH also decreased under stress.
During recovery from severe stress, the activity of XDH and uricase further decreased, whilst that of allantoinase and allantoicase increased compared to the control. This corresponded with the higher content of ureides during recovery. The recovery in other enzymes was not complete although leaf water potential and nodule moisture content recovered fully within 24 h.  相似文献   

14.
Rat liver arginase was purified and five monoclonal antibodies were produced by fusion of spleen cells from a Balb/c mouse and the myeloma cell line P3-X36-Ag-U1. One, R2D19, of five antibodies belonged to the IgG2a subclass, the other four, R1D81, R1G11, R2E10, and R2G51, were of the IgG1 type. The R1D81 cross-reacted with human liver arginase. This antibody inhibited the arginase activity, competing with arginine. These results suggest that R1D81 binds to the catalytic site of arginase. The R2D19 also inhibited the enzyme activity but acted as a noncompetitive inhibitor. With the use of R1D81 and a polyclonal anti-human liver arginase antibody conjugated with alkaline phosphatase, a sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of human arginase. Specificity of monoclonal antibodies for rat liver arginase was examined by means of the sandwich ELISA. Eight pairs of monoclonal antibodies could form a sandwich with the arginase. Only the R2E10 could be used for both the first and the second antibody in the sandwich system. In other cases, monoclonal antibodies could not be interchanged between solid and liquid phase.  相似文献   

15.
Rabbit antibody directed to homogeneously purified mouse liver delta-aminolevulinic acid dehydratase cross-reacted with the enzyme in erythrocytes, spleen, kidney and brain in the mouse. The antibody also cross-reacted with the enzyme in the rat, hamster and gerbil, but not in the rabbit, guinea pig, cattle, chick embryo, and human. In contrast, rabbit antibody against the human enzyme partially recognized the monkey enzyme, but not the enzyme in the other species. The species specificity of delta-aminolevulinic acid dehydratase in this study was consistent with the phylogenetic evolution of the species examined.  相似文献   

16.
Rabbit antibody directed to homogeneously purified mouse liver δ-aminolevulinic acid dehydratase cross-reacted with the enzyme in erythrocytes, spleen, kidney and brain in the mouse. The antibody also cross-reacted with the enzyme in the rat, hamster and gerbil, but not in the rabbit, guinea pig, cattle, chick embryo, and human. In contrast, rabbit antibody against the human enzyme partially recognized the monkey enzyme, but not the enzyme in the other species. The species specificity of δ-aminolevulinic acid dehydratase in this study was consistent with the phylogenetic evolution of the species examined.  相似文献   

17.
Roger W. Parish 《Planta》1972,104(3):247-251
Summary Peroxisomes isolated from maize root tips contained urate oxidase, although the supplementary enzymes allantoinase, allantoicase and NADH-glyoxylate reductase were not detected. Some glutamate-oxalacetate transaminase was present in peroxisomes. Enzymes of two other pathways occuring in plant peroxisomes, namely glycolate metabolism and the glyoxylate cycle, were not present. The root peroxisome thus resembles peroxisomes of the Arum spadix and supports the concept that peroxisomes constitute a dynamic and differentiating system.  相似文献   

18.
Here we report on the production of functional recombinant SBPase of Chlamydomonas sp. W80 in Escherichia coli and the one-step purification of a polyhistidine-tagged fusion protein. The polyclonal antibody was raised against purified recombinant enzyme and cross-reacted with crude SBPase from Chlamydomonas, spinach, tobacco, and Arabidopsis leaves. Further, we investigated the levels of protein and activity of SBPase in different tissues of Arabidopsis plants.  相似文献   

19.
We have shown that allantoin degradation in Saccharomyces cerevisiae proceeds exclusively through the intermediate formation of allantoic acid, urea, and allophanic acid. The number of reactions between allantoic acid and urea, however, remains obscure owing to our inability to isolate a mutant defective in ureidoglycolate hydrolase. Structural genes for the enzymes, allantoinase (dal1) and allantoicase (dal2) are located on chromosome IX promixal to the centromere in the order dal1-dal2-lysl.  相似文献   

20.
Abstract The subcellular location of the enzymes of purine breakdown in the yeast Candida famata , which grows on uric acid as sole carbon and nitrogen source, has been examined by subcellular fractionation methods. Uricase was confirmed as being peroxisomal, but the other three enzymes, allantoinase, allantoicase and ureidoglycollate lyase were shown to be cytosolic. In addition the peroxisomes harboured catalase and the key enzymes of the glyoxylate cycle, isocitrate lyase and malate synthase.  相似文献   

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