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1.
1. Submandibular glands from four species of mammal have been shown to contain a hyaluronidase active at acid pH; glands from dog and cat had a much higher content of this enzyme than has been found in other sources. 2. Product formation from hyaluronate after 24hr. incubation was almost the same as with testicular hyaluronidase, indicating that the enzyme is an endo-poly-β-hexosaminidase. 3. When submandibular-gland homogenates were fractionated by the scheme developed for liver by de Duve, Pressman, Gianetto, Wattiaux & Appelmans (1955), all the enzymes assayed, except cytochrome c oxidase, were found to occur partly in the soluble fraction and partly in the particulate fractions. Among the particular fractions, the highest specific activity was found in the heavy-mitochondrial fraction for cytochrome c oxidase, in the microsomal fraction for alkaline phosphatase and in the light-mitochondrial fraction for acid phosphatase, β-N-acetylhexosaminidase and acid-active hyaluronidase. 4. Release of the enzyme activity from the sedimentable fractions occurred in 0·1% Triton X-100 or after high-speed homogenization. 5. Stimulation of dogs by pilocarpine was found to decrease the hyaluronidase content of the submandibular gland by 5% and to cause the occurrence of a corresponding amount of acid-active hyaluronidase in the submandibular saliva. 6. The results are discussed in relation to the subcellular localization of hyaluronidase.  相似文献   

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Guinea-pig submandibular kallikrein has been purified from the glands to electrophoretic homogeneity by conventional procedures. The enzyme is active as a kininogenase, releasing kallidin at a rate of 462 micrograms/min per mg of protein from bovine kininogen, and proved potently hypotensive in the guinea pig and in the dog, properties which indicate its tissue kallikrein nature. The specific activity determined on the substrate N-alpha-benzoyl-L-arginine ethyl ester (11.1 mumol/min per mg of protein) is much lower than that measured with N-acetyl-L-phenylalanyl-L-arginine ethyl ester (483 mumol/min per mg of protein). The latter value is of an order of magnitude comparable with the specific activities of other tissue kallikreins determined with this sensitive kallikrein substrate. The enzyme is a glycoprotein consisting of 237 amino acid residues and containing three to four glucosamine molecules. Its amino acid composition is not identical with that reported for guinea-pig coagulating-gland kallikrein, but is remarkably similar to that of the porcine tissue kallikreins. Apparent Mr values are 29000 (sodium dodecyl sulphate/polyacrylamide-gel electrophoresis) or 34000 (gel filtration). The amino acid sequence of the first 31 N-terminal residues was determined and was found to be closely homologous with that of other tissue kallikreins.  相似文献   

3.
Hyaluronidase from bull sperm was fractionated by ammonium sulfate and further purified by DEAE-cellulose and Sephadex chromatography. The highly purified hyaluronidase preparation showed 2,370 units per mg of protein (68,730 N.F. units per mg of protein), i.e. 182-fold purification. Disc gel electrophoresis showed one major component. The molecular weight of bull sperm hyaluronidase was 62,000 by sodium dodecyl sulfate gel electrophoresis. Hyaluronidase from bull sperm has optimum activity at pH 3.8 and an absolute requirement for cations. Kplus and Naplus have a greater effect than Ca2plus, Mg2plus, and Mn2plus, whereas Co2plus, Cu2plus, and Zn2plus do not affect the enzyme activity. Purified preparations are less stable than crude extracts stored frozen at minus 15 degrees. Km of hyaluronidase with hyaluronic acid as substrate is 3.7 mg per ml and Vmax is 2.4 mumol per min by Hofstee plot.  相似文献   

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Hyaluronidase [EC 3.2.1.35] was isolated from human placenta and purified by ammonium sulfate fractionation, DEAE-cellulose column chromatography and gel filtration on Sephadex G-150. Its isoelectric point was at pH 5.2 and the molecular weight was 7 X 10(4) based on Sephadex G-200 gel filtration data. This enzyme was very stable at temperatures below 30 degree, but was almost completely inactivated at 60degree within 30 min. Its optimum pH was 3.9, a characteristic property of a lysosomal hyaluronidase. The Michaelis constant was 1.18 x 10(-1) mg per ml with purified hyaluronate. This enzyme depolymerized hyaluronate, chondroitin, chondroitin 4-sulfate and 6-sulfate, and the end product formed from hyaluronate was tetrasaccharide. Its biological diffusing activity was statistically significant on intracutaneous injection of 1.86 mU of the hyaluronidase into the back skine of a rabbit.  相似文献   

6.
The effect of T3 (3,3',5-tri-iodothyronine) on protein turnover in skeletal and cardiac muscle was measured in intact rats by means of a 6 h [14C]tyrosine-infusion technique. Treatment with 25-30 micrograms of T3/100 g body wt. daily for 4-7 days increased the fractional rate of protein synthesis in skeletal muscle. Since the fractional growth rate of the muscle was decreased or unchanged, T3 treatment increased the rate of muscle protein breakdown. These findings suggest that increased protein degradation is an important factor in decreasing skeletal-muscle mass in hyperthyroidism. In contrast with skeletal muscle, T3 treatment for 7 days caused an equivalent increase in the rate of cardiac muscle growth and protein synthesis. This suggests that hyperthyroidism does not increase protein breakdown in heart muscle as it does in skeletal muscle. The failure of T3 to increase proteolysis in heart muscle may be due to a different action on the cardiac myocyte or to systemic effects of T3 which increase cardiac work.  相似文献   

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A new method for obtaining highly purified hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1.25) in high yield is described. Bull seminal plasma was fractionated with (NH4)2 SO4 and the 30 to 65% saturation fractions were applied to a DEAE-cellulose column. The first protein peak contained hyaluronidase, beta-N-acetylglucosaminidase and beta-glucuronidase. The latter two enzymes were separated by gel filtration on Sephadex G-200. The hyaluronidase was further purified by a Concanavalin-A Sepharose 4B affinity column. By gradient elution with alpha-methyl-D-glucoside a fraction which had a specific activity of 1998 units/mg protein (57 942 National Formulary Standard units/mg protein) was obtained. The highly purified enzyme showed one major protein band on acrylamide gel electrophoresis at pH 4.3. The purified hyaluronidase did not show any beta-glucuronidase or beta-N-acetylglucosaminidase activities. The percent yield of purified hyaluronidase calculated on the basis of total activity was ten times higher than by any pervious method [Yang, C.H. and Srivastava, P.N. (1975) J. Biol. Chem. 250, 79-83].  相似文献   

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1. A marine hyaluronidase was purified 261-fold from the stonefish (Synanceja horrida) crude venom using Sephacryl S-200 HR and heparin affinity-gel chromatography. 2. Stonefish hyaluronidase has a pI of 9.2, a mol. wt of 62,000 and it was purified to a very high spec. act. of 1.6 x 10(6) NFU/mg protein. 3. It was heat sensitive and was inhibited by Cu2+, Hg2+ and heparin. 4. Stonefish hyaluronidase did not contain any haemorrhagic or lethal activity. 5. The N-terminal sequence of stonefish hyaluronidase has been determined to be A-P-S-X-D-E-G-N-K-K-A-D-N-L-L-V-K-K-I-N.  相似文献   

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Human placental alpha-fucosidase (EC 3.2.1.51) has been extensively purified and partially characterized with respect to kinetic and structured properties. Although the enzyme seems to be separated by DEAE-cellulose chromatography in two forms which differ in their molecular weight and thermostability, an interconversion between the two forms takes place during storage and/or electrofocusing so that the same peaks of activity, revealed by the latter technique, are found before and after DEAE-cellulose chrome. The heterogeneous peaks of activity revealed by isoelectrofocusing show a reproducible pattern in the different tissues examined, except in serum where their pI values are consistently more acidic.  相似文献   

16.
Phosphoglycolate phosphatase (EC 3.1.3.18) was purified 1500-fold from field-grown tobacco leaves by acetone fractionation, DEAE-cellulose and molecular sieve chromatography, and preparative polyacrylamide gel electrophoresis. Preparations were judged 90 to 95% homogeneous by chromatography on DEAE-cellulose, polyacrylamide gel electrophoresis, and by isoelectric focusing. The highest specific activity obtained was 468 mumol of phosphate released/min/mg of protein. The native protein has a molecular weight of 80,500 by Ferguson plot analysis and 86,300 by sedimentation velocity on sucrose density gradients. Sodium dodecyl sulfate-polyacrylamide gels gave a molecular weight of 20,700, indicating the P-glycolate phosphatase is a tetramer with identical or near identical subunits. The enzyme, freshly purified or in crude homogenates, had a pI of 3.8 to 3.9 pH units by isoelectric focusing. Phosphosphoglycolate phosphatase from spinach leaves has a molecular weight of 93,000 and, unlike the enzyme from tobacco leaves, it is extremely unstable after DEAE-cellulose chromatography and is inactivated by lipase (EC 3.1.1.3). The phosphatase from both plants was stabilized by the addition of citrate or isocitrate in the buffers. Ribose 5-phosphate is a competitive inhibitor of phosphoglycolate phosphatase at physiological concentration, while other phosphate esters of the photosynthetic carbon cycle were without effect.  相似文献   

17.
基因工程犬干扰素α的制备及纯化工艺   总被引:1,自引:0,他引:1  
目的:运用基因工程技术制备高活性的重组犬仪干扰素。方法:用发酵罐大量培养工程菌,经超声破碎菌体获粗制包涵体,用1% TritonX-100洗涤去除部分杂蛋白后,以8mol/L尿素溶解包涵体,稀释复性并超滤浓缩,用阴离子柱层析法纯化目的蛋白,测定重组犬干扰素d的活性。结果:得到的重组犬干扰素仅的相对分子质量为19×10^3,蛋白含量为0.55mg/mL,纯度95.65%,目的蛋白回收率为13.75%,活性1.78×10^7U/mL,比活性3.24×10^7U/mg。结论:制备了高纯度且具有高活性的重组犬α干扰素。  相似文献   

18.
Ferritin-binding protein (FBP) is known to interact with circulating ferritins in mammals. Canine FBPs were purified from canine serum by affinity chromatography and were identified as IgM, IgG, and IgA by immunoblotting with alkaline phosphatase-labeled antibodies to canine IgM, IgG, and IgA heavy chains. Following further purification by application to a Sephacryl S-300 column, canine FBPs were separated into 81.3- and 27.7-kDa bands by sodium dodecyl sulfate-polyacryamide gel electrophoresis, and the 81.3-kDa band reacted with the anti-canine IgM heavy chain antibody. Purified canine FBP bound to canine liver ferritin, but not to canine albumin and transferrin. FBP showed greater binding to the expressed bovine ferritin H-chain homopolymer than to the expressed bovine ferritin L-chain homopolymer. The binding of FBP with canine liver ferritin was dose-dependently inhibited by anti-rat liver ferritin antibody, and the anti-ferritin antibody dissociated the bound FBP in a dose-dependent manner, even after binding FBP with liver ferritin. The canine ferritin H subunit peptide fragment with amino acid residues 148–155 (NH2-GDHVTNLR-COOH) in its C-terminal region was recognized by FBP. These results indicate that canine serum FBPs are autoantibodies to ferritin (IgM, IgG, and IgA) and that anti-ferritin autoantibody (IgM) recognizes the C-terminal region of ferritin H subunit.  相似文献   

19.
Potato phenolases. Purification and properties   总被引:7,自引:0,他引:7  
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20.
Staphylocoagulase, an exoprotein of coagulase-positive Staphylococci, has been purified to a state in which only trace amounts of contaminating proteins are detectable. Aspartic acid was found as a single N-terminal amino acid in this preparation. The molecular weight is 61 000; the isoelectric point lies as pH 4.53. The amino acid composition was determined.  相似文献   

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