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1.
Lysosomal serine and cysteine proteases are reported to play a role in collagen degradation. In this study, the activities of the lysosomal cysteine proteases cathepsin B and H, dipeptidyl peptidase I, and the serine protease tripeptidyl peptidase I and dipeptidyl peptidase II, all ascribed a role in collagen digestion, were compared with those of the aspartate protease cathepsin D, and lysosomal glycosidases in leukocytes from rheumatoid arthritis patients at different stages of the disease. In all patients the activities of cysteine protease cathepsin B, dipeptidyl peptidase I, aspartate protease cathepsin D, and two glycosidases were elevated, but the activities of the serine proteases tripeptidyl peptidase I, dipeptidyl peptidase II, and the cysteine protease cathepsin H was unchanged. The magnitude of the increased activity was correlated with the duration of the disease. Patients with long-standing RA (10 years or more) had higher cysteine protease activity in their leukocytes than did those with disease of shorter duration. This tendency suggests that elevated lysosomal cysteine protease activities, together with aspartate protease cathepsin D and lysosomal glycosidases (but not serine proteases), are associated with progression of rheumatoid arthritis.  相似文献   

2.
Total, Mg2+, and Na+, K+ ATPase activities were studied in fresh brain homogenates of the audiogenic seizure (AGS)-resistant C57BL/6J (B6) and AGS-susceptible DBA/2J (D2) inbred strains and in 13 B6 X D2 (BXD) recombinant inbred (RI) strains. These activities were also studied in the D2.B6-Iasb congenic mice, that are similar genetically to D2 mice, except for the Iasb gene which inhibits the spread of AGS activity. The total and Mg2+ ATPase activities of the brainstem were significantly lower in the D2 than in the B6 mice at 21 days of age. No differences were found between these strains for Na+,K+ ATPase activity. The total, Mg2+, and Na+,K+ ATPase activities in the B6 brainstem did not change noticeably from 21 to 80 days of age. In the D2 brainstem, however, the Mg2+ activity increased with age, and the Na+,K+ ATPase activity decreased from 30 to 80 days of age. No genetic associations could be found between AGS susceptibility and total or Mg2+ ATPase activities in the D2.B6-Iasb mice or among the 13 BXD RI strains. Hence, differences in genetic background, rather than differences in AGS susceptibility, can account for the lower ATPase activities in 21-day-old D2 mice. Further, the Mg2+ and Na+,K+ ATPase activities appear to be regulated by more than one gene. This study emphasizes the utility of RI and congenic strains for testing the biochemical basis of AGS susceptibility in mice.  相似文献   

3.
Roles of cathepsins in reperfusion-induced apoptosis in cultured astrocytes   总被引:2,自引:0,他引:2  
Astrocytic apoptosis may play a role in the central nervous system injury. We previously showed that reperfusion of cultured astrocytes with normal medium after exposure to hydrogen peroxide (H(2)O(2))-containing medium causes apoptosis. This study examines the involvement of the lysosomal enzymes cathepsins B and D in the astrocytic apoptosis. Reperfusion after exposure to H(2)O(2) caused a marked increase in caspase-3 and cathepsin D activities and a marked decrease in cathepsin B activity. Pepstatin A, an inhibitor of cathepsin D, and acetyl-L-aspartyl-L-methionyl-L-glutaminyl-L-aspart-1-aldehyde (Ac-DMQD-CHO), a specific inhibitor of caspase-3, blocked the H(2)O(2)-induced decrease in cell viability and DNA ladder formation in cultured rat astrocytes. The (L-3-trans-(propylcarbamoyl)oxirane-2-carbonyl)-L-isoleucyl-L-proline methyl ester (CA074 Me), a specific inhibitor of cathepsin B, did not affect the H(2)O(2)-induced cell injury. On the other hand, CA074 Me decreased cell viability with DNA ladder formation when cultured in the presence of Ac-DMQD-CHO. This caspase-independent apoptosis was attenuated by the addition of the cathepsin D inhibitor pepstatin A. Caspase-3 like activity was markedly inhibited by Ac-DMQD-CHO and partially by pepstatin A. Pepstatin A and CA074 Me inhibited cathepsin B and cathepsin D activities, respectively, in the presence and absence of Ac-DMQD-CHO. These results suggest that cathepsins B and D are involved in astrocytic apoptosis: cathepsin D acts as a death-inducing factor upstream of caspase-3 and the caspase-independent apoptosis is regulated antagonistically by cathepsins B and D.  相似文献   

4.
1. Activities of cathepsins B, D and H were measured in leg and breast muscles of fast growing (broiler) and slow growing (layer) chicks at eight time intervals between 1 and 29 days of age. 2. These enzyme activities were also measured in muscles from fast and slow growing chicks given a low protein (125 g/kg crude protein) diet between the ages of 17 and 24 days. 3. Activities of none of these cathepsins differed greatly between muscle type or strain of chick. However in both strains of chick cathepsin D and H in muscles significantly decreased with increasing age (muscle size) of the chick. Cathepsin D activity also increased when muscle proteolytic rates were increased by feeding a low protein diet. This latter effect was significant only in the muscles of fast growing chicks. 4. The results suggest that lysosomal proteases are not responsible for the differences in muscle protein degradation and growth between fast and slow growing strains of chicks, or between muscle types in the chick.  相似文献   

5.
Cathepsin B, H, L and D activities in liver lysosomes were compared between species. Although cathepsin B and D were detected in bovine, pig, chicken and rat liver, striking species differences were evident for cathepsin H and L. Cathepsin L activity was particularly high in chicken lysosomal extracts, but could not be detected in bovine and pig extracts. Whereas there was no significant cathepsin H activity in bovine extracts, rat liver lysosomal extracts contained large amounts of cathepsin H activity.  相似文献   

6.
F Toldrá  E Rico  J Flores 《Biochimie》1992,74(3):291-296
The effect of curing agents (salt, nitrate, ascorbic acid and glucose) and processing parameters (pH, water activity and drying and cooking temperatures) on pork muscle cathepsins B, D, H and L as well as leucyl, arginyl and tyrosyl hydrolysing activities is reported. Salt (60 g/l) showed a powerful inhibitory effect, especially on cathepsin D and aminopeptidase activities where less than 13% of the original activity was recovered. Cathepsin H was also affected (38% of the original activity) while cathepsins B and B+L recovered 72.5 and 63.0%, respectively. Nitrate (0.2-0.25 g/l) and ascorbic acid (0.2-0.4 g/l) did not significantly affect the enzyme activities. On the other hand, 0.5-2 g/l of glucose activated both cathepsins B and D with an increase of 39.5 and 28.5% and also leucyl and arginyl hydrolysing activities which were 75.0 and 24.0%, respectively. No aminopeptidase activity was detected when assayed in 100 mM sodium citrate buffer, pH 5.1. Cathepsin H was also very affected at that pH and only 12.0% of activity was recovered. A decrease in water activity, especially below 0.84, also affected the enzyme activities which were found below 50%. Temperatures in the usual range of the drying process (22 and 30 degrees C) gave substantial enzyme activities (around 40-50 and 80%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Alcohol-producing strains of Clostridium beijerinckii (Clostridium butylicum) produce, besides acetone, either n-butanol and ethanol or n-butanol, ethanol, and isopropanol as their characteristic products. Alcohol dehydrogenase has been isolated from a strain (NRRL B593) of C. beijerinckii producing isopropanol and from a strain (NRRL B592) not producing isopropanol. Butanol-ethanol dehydrogenase activities were present in both strains, but isopropanol dehydrogenase activity was present only in the isopropanol-producing strain. The butanol-ethanol dehydrogenase of strain NRRL B592 had M(r) 66,000 and a K(m) of 6 muM for butyraldehyde. In contrast, the butanol-ethanol-isopropanol dehydrogenase of strain NRRL B593 had a M(r) 100,000 and K(m)s of 9.5 and 1.0 mM for butyraldehyde and acetone, respectively. In a purification by four different types of separatory methods (DEAE-cellulose, hydroxyapatite, Sephacryl S-300, and Matrex Gel Red A), butanol-ethanol-isopropanol dehydrogenase activities of strain NRRL B593 were purified up to 200-fold (10 to 30% yield), and these activities were not separated. Gel electrophoresis followed by activity stain also revealed distinct mobilities for the butanol-ethanol dehydrogenase of strain NRRL B592 and the butanol-ethanol-isopropanol dehydrogenase of strain NRRL B593. In cell extracts from both strains, a higher alcohol dehydrogenase activity was measured with NADP(H) than with NAD(H). The 150- to 200-fold-purified alcohol dehydrogenase from strain NRRL B593 did not show any NAD(H)-linked activities. The K(m) for NADPH was 31 muM (with butyraldehyde as cosubstrate) and 18 muM (with acetone as cosubstrate) for the alcohol dehydrogenase of strain NRRL B593. This study showed that the alcohol dehydrogenases from two strains of C. beijerinckii differed significantly.  相似文献   

8.
石勇  杨小菊  赵昕  李新荣 《生态学杂志》2012,31(5):1136-1142
以生物土壤结皮中土生对齿藓(Didymodon vinealis)和真藓(Bryum argenteum)为材料,研究了逐渐干旱胁迫下二者的信号传导相关物质的响应。结果表明:随干旱胁迫的增强,2种苔藓的细胞膜与液泡膜H+-ATPase活性增强,提高了二者的K+含量,增加了二者的渗透压,促进了二者的抗旱信号转导物质的合成;ABA对二者的信号转导作用都不明显,NO对土生对齿藓的抗旱作用不明显,但能提高真藓的抗旱性,而Ca2+只对土生对齿藓有明显信号转导作用,对真藓作用不明显。  相似文献   

9.
采用氯仿-甲醇有机溶剂提取、常压硅胶柱层析等方法进行分离纯化,从微劳马尾藻的提取物中分离纯化了6个化合物;根据核磁共振谱分析及文献解析化合物B、D分别确定为棕榈酰基.油酰基-3-O-α-D-吡喃葡萄糖基甘油和肉豆蔻酰基-油酰基-3-O-α-D-吡喃葡萄糖基甘油;使用酶标仪体外测定化合物的纤溶活性,发现化合物B使纤溶作用提高了10%~30%,化合物D的纤溶促进作用弱于化合物B;分离纯化的纤溶促进化合物B和D属于甘油糖脂类化合物。本文首次从微劳马尾藻分离得到了肉豆蔻酰基.油酰基-3-O-α-D-吡喃葡萄糖基甘油。  相似文献   

10.
Two new benzoquinones, heliotropinones A and B, have been isolated from the aerial parts of Heliotropium ovalifolium. Their structures were elucidated by spectrometric methods including high resolution electrospray ionization (ESI-HR), EI mass spectrometry, 1H, 13C and 2D NMR experiments. The two quinones demonstrated antifungal activities against Cladosporium cucumerinum and Candida albicans as well as antibacterial activity against Bacillus subtilis.  相似文献   

11.
Fine structure of the body wall cuticle of Heterodera schachtii is compared with respect to age and body region of the female. The cuticle is more complex than previously reported. In newly molted females only layers A, B, and C are present, but 4 weeks after the final molt a thin D layer is present between the midbody and base of the cone. This D layer is absent in the cone of H. schachtii, regardless of age. As females age, an additional layer E is produced and includes zones E₁ and E₂. Zone El apparently is unique to H. schachtii, whereas E₂ is likely to be homologous with a similar layer in Atalodera. In the cone of old females (ca. 8 weeks after the final molt) of H. schachtii, the two zones become irregular in shape and comprise bullae. The presence of a thin D layer in Heterodera strengthens the previous hypothesis of a single ancestor of cyst nematodes.  相似文献   

12.
Spraying with two preparations of D.D.T. had a negligible effect on the maturation of outdoor tomatoes and of summer cabbage. Spraying with a commercial D.D.T. suspension damaged cucurbits and treatment with the suspension base distorted glasshouse cucumbers during one season only.
Benzene hexachloride (B.H.C.) sprays did not affect the yield or flavour of tomatoes, but, at concentrations higher than those normally used, they severely scorched radish, turnip, swede, kale, spinach and beetroot seedlings. The application of B.H.C. dusts stunted seedlings of radish.
On one occasion young potato foliage was damaged by relatively high concentrations of two compounded B.H.C. sprays and by B.H.C. dust but late-season older foliage was unaffected. A spray compounded from B.H.C. dispersible powder caused tainting of potatoes, peas, carrots, beetroot, marrows, cauliflowers and lettuce. Apples and plums treated with B.H.C. spray preparations developed a taint after cooking.  相似文献   

13.
A previous study led to the discovery of new proteinases in yeast (Achstetter, T., Ehmann, C., and Wolf, D. H. (1981) Arch. Biochem. Biophys. 207, 445-454). The search for proteolytic enzymes active in the neutral pH range has been extended. Studies were done on a mutant lacking four well-known proteinases involved in protein degradation, the two endoproteinases A and B and the two carboxypeptidases Y and S. Twenty-nine chromogenic peptides (amino terminally blocked peptidyl-4-nitroanilides) as well as [3H]methylcasein were used as substrates in this search. For the detection of endoproteolytic activity using chromogenic peptide substrates two versions of the assay were used. In one system the direct cleavage of the 4-nitroanilide bond was measured. In the second, the cleavage of the chromogenic peptide at some site other than the 4-nitroanilide bond was measured. Both variations led to the discovery of multiple proteinase activities. Regulation of these proteolytic activities under different growth conditions of cells was observed. Proteolytic activity on [3H]methylcasein was also found. Ion-exchange chromatography and gel filtration were used for the reproducible separation of the multiple proteolytic activities.  相似文献   

14.
In addition to the known cordiaquinones A and B, two novel meroterpenoid naphthoquinones, named cordiaquinones J and K, have been isolated from the roots of Cordia curassavica. Their structures were elucidated by spectrometric methods including EI, D/CI mass spectrometry, 1H, 13C and 2D-NMR experiments. The four naphthoquinones demonstrated antifungal activities against Cladosporium cucumerinum, Candida albicans and toxic properties against larvae of the yellow fever-transmitting mosquito Aedes aegypti.  相似文献   

15.
Protein L-isoaspartyl methyltransferase (PIMT) has been implicated in the repair or metabolism of proteins containing atypical L-isoaspartyl peptide bonds. The repair hypothesis is supported by previous studies demonstrating in vitro repair of isoaspartyl peptides via formation of a succinimide intermediate. Utilization of this mechanism in vivo predicts that PIMT modification sites should exhibit significant racemization as a side reaction to the main repair pathway. We therefore studied the D/L ratio of aspartic acid at specific sites in histone H2B, a known target of PIMT in vivo. Using H2B from canine brain, we found that Asp25 (the major PIMT target site in H2B) was significantly racemized, exhibiting d/l ratios as high as 0.12, whereas Asp51, a comparison site, exhibited negligible racemization (D/L < or = 0.01). Racemization of Asp25 was independent of animal age over the range of 2-15 years. Using H2B from 2-3-week mouse brain, we found a similar D/L ratio (0.14) at Asp25 in wild type mice, but substantially less racemization (D/L = 0.035) at Asp25 in PIMT-deficient mice. These findings suggest that PIMT functions in the repair, rather than the metabolic turnover, of isoaspartyl proteins in vivo. Because PIMT has numerous substrates in cells, these findings also suggest that D-aspartate may be more common in cellular proteins than hitherto imagined and that its occurrence, in some proteins at least, is independent of animal age.  相似文献   

16.
17.
Two cytochrome P450 enzymes, cinnamate 4-hydroxylase (C4H) and 3,9-dihydroxypterocarpan 6a-hydroxylase (D6aH), were isolated from elicitor-challenged soybean (Glycine max) cell cultures (G. Kochs and H. Grisebach, 1989, Arch. Biochem. Biophys. 273, 543-553). An earlier purification protocol was improved by the use of new chromatographic media, leading to a higher yield of enzymatic activity. After separation of C4H from D6aH on hydroxyapatite, the C4H was identified using anti-C4H antibody from Jerusalem artichoke (Helianthus tuberosus) (B. Gabriac et al., 1991, Arch. Biochem. Biophys. 288, 302-309). The two proteins show molecular weights of about 58,000 for C4H and about 55,000 for D6aH on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Both enzyme activities are dependent on NADPH:cytochrome P450 reductase and cross-react with their respective antibodies. Both cytochrome P450 subspecies show substrate binding and CO-difference spectra typical for cytochrome P450 and were found to be glycoproteins by their cross-reaction with biotinylated lectins in Western blot. The N-terminal sequence of C4H from soybean shows high similarity to the N-terminus of C4H from Jerusalem artichoke.  相似文献   

18.
Reviews     
《The New phytologist》1989,113(3):423-430
The Flavonoids. Advances in Research since 1980. Ed. by J. B. H arborne .
Hungry crops : a guide to nutrient deficiencies in field crops By N. J. G rundon .
Microbial ecology: organisms, habitats, activities. By H einz S tolp .
Evolutionary Biology of the Fungi. Ed. by A. D. M. R ayner , C. M. B rasier and D. M oore .
Micro-algal Biotechnology . Edited by M.A. B orowitzka and L. J. B orowitzka and L. J. B orowitzka .
Experimental Phycology: A laboratory manual Edited by C hristopher S. L obban , D avid J. C hapman , and B runo P. K remer .
100 Families of Flowering Plants. By M. H ickey and C. K ing .
Differentiation Patterns in Higher Plants. Edited by K. M. U rbanska .
The Living Tundra. By Yu. I. C hernov , Translated by D. L öve .
North American Terrestrial Vegetation. Edited by M. G. B arbour & W. D. B illings .
Biogeography and Quaternary History in Tropical Latin America. By T. C. W hitmore and G. T. P rance (Editors).
Biogeographical Evolution of the Malay Archipelago . By T. C. W hitmore (Editor).
Postglacial Vegetation of Canada. By J. C. R ichie .  相似文献   

19.
Summary Salt-soluble proteins from the endosperms of wheat, barley, and rye have been separated by nonequilibrium electrofocusing x electrophoresis. Genes encoding 14 of the 25 components observed in wheat have been unambiguously assigned to 10 different chromosomes (1B, 3B, 3D, 4A, 4D, 5B, 6B, 6D, 7B, 7D) by analysis of the compensated nulli-tetrasomic series. Five more wheat proteins seem to be controlled by group 2 chromosomes. Analysis of wheat-barley and wheat-rye addition lines has led to the location of genes for 6 out of 20 barley proteins in 4 different chromosomes (1H, 3H, 4H, 6H; 1H is homoeologous to group 7 chromosomes of wheat) and of genes for 5 out of 20 rye proteins in two different chromosomes (2R, 4R). The relationship between the proteins reported here and previously characterized ones is discussed.  相似文献   

20.
The influence of long term rearing conditions on the hematological and serum biochemical values in laboratory-bred female cynomolgus monkeys (Macaca fascicularis) was studied under the following two conditions. Group A: New born infants were nursed by their mothers for at least 12 weeks after birth. After weaning, four monkeys of approximately equal age and body weight were kept in a relatively small cage (90 cm W x 60 cm D x 60 cm H) and reared to five years of age. These rearing conditions are commonly used in the breeding program of our primate center. Group B: One male and five females of wild origin were introduced into a relatively large cage (180 cm W x 180 cm D x 160 cm H). Female monkeys born in these cages were used in this study. All of them were reared by their own mothers and grew well in these cages. Male monkeys born in these cages were removed at about 3.5 years of age. Hematological and serum biochemical values between the two groups in each age class were compared and analyzed by the canonical discriminant analysis (the discriminant analysis with reduction of dimensionality). Age correlated highly with the value of the first canonical variate. The second canonical variate detected a difference in the blood hematology and biochemistry probably induced by the difference in rearing conditions.  相似文献   

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