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121.
Staphylokinase is a 135 amino acid protein produced by certain strains of Staphylococcus aureus. It belongs to fibrin-specific plasminogen activator. Staphylokinase converts plasminogen--the inactive proenzyme--to the plasmin, which dissolves the fibrin of a blood clots. This review will focus on the biochemical and thrombolytic properties of staphylokinase and its derivatives, which would make use of treatment in acute myocardial infarction and other cardiovascular diseases. 相似文献
122.
Enzymes in Bast Fibrous Plant Processing 总被引:7,自引:0,他引:7
Kozlowski R Batog J Konczewicz W Mackiewicz-Talarczyk M Muzyczek M Sedelnik N Tanska B 《Biotechnology letters》2006,28(10):761-765
The program COST Action 847 Textile Quality and Biotechnology (2000–2005) has given an excellent chance to review the possibilities of the research, aiming at development of the industrial application of enzymes for bast fibrous plant degumming and primary processing. The recent advancements in enzymatic processing of bast fibrous plants (flax, hemp, jute, ramie and alike plants) and related textiles are given. The performance of enzymes in degumming, modification of bast fibres, roving, yarn, related fabrics as well as enzymatic bonding of lignocellulosic composites is provided. 相似文献
123.
Szewczyk A Skalska J Głab M Kulawiak B Malińska D Koszela-Piotrowska I Kunz WS 《Biochimica et biophysica acta》2006,1757(5-6):715-720
Mitochondrial potassium channels, such as ATP-regulated or large conductance Ca2+ -activated and voltage gated channels were implicated in cytoprotective phenomenon in different tissues. Basic effects of these channels activity include changes in mitochondrial matrix volume, mitochondrial respiration and membrane potential, and generation of reactive oxygen species. In this paper, we describe the pharmacological properties of mitochondrial potassium channels and their modulation by channel inhibitors and potassium channel openers. We also discuss potential side effects of these substances. 相似文献
124.
Core histones are subjected to various post-translational modifications, and one of them, most intensively studied in plants, is the methylation of histone H3. In the majority of analyzed plant species, dimethylation of H3 at lysine 9 (H3K9me2) is detected in heterochromatin domains, whereas methylation of H3 at lysine 4 (H3K4me2) is detected in euchromatin domains. The distribution of H3K9me2 in the interphase nucleus seems to be correlated with genome size, chromatin organization, but also with tissue specificity. In this paper, we present the analysis of the pattern and level of histone H3 methylation for two allotetraploid and one diploid Brassica species. We have found that the pattern of H3K9me2 in interphase nuclei from root meristematic tissue is comparable within the analyzed species and includes both heterochromatin and euchromatin, but the level of modification differs not only among species but even among nuclei in the same phase of the cell cycle within one species. Moreover, the differences in the level of H3K9me2 are not directly coupled with DNA content in the nuclei and are probably tissue specific. 相似文献
125.
The efficiency of hydrolysis of fungal (Fusarium spp.) cell wall and rye root cell wall by crude enzymatic complexes from (42-day-old) cultures of three F. culmorum isolates, a plant growth-promoting rhizosphere isolate (PGPF) DEMFc2, a deleterious rhizosphere isolate (DRMO) DEMFc5, and a pathogenic isolate DEMFc37, as well as two other, pathogenic isolates belonging to F. oxysporum and F. graminearum species was studied. In the enzymatic complexes originating from the Fusarium?spp. cultures, the activities of the following cell wall-degrading enzymes were identified: glucanases, chitinases, xylanases, endocellulases, exocellulases, pectinases, and polygalacturonases. The preparation originating from a culture of the PGPF isolate was the least efficient in plant cell wall (PCW) hydrolysis. There were no significant differences in the efficiency of PCW hydrolysis between preparations from cultures of the DRMO and the pathogenic isolates. PGPF was the most efficient in liberating reducing sugars and N-acetylglucosamine (GlcNAc) from fungal cell walls (FCW). Xylanase activities of the enzymatic complexes were strongly positively (R?>?+0.9) correlated with their efficiency in hydrolyzing PCW, whereas chitinase activities were correlated with the efficiency in FCW hydrolysis. 相似文献
126.
Dietrich-Muszalska A Malinowska J Olas B Głowacki R Bald E Wachowicz B Rabe-Jabłońska J 《Neurochemical research》2012,37(5):1057-1062
The mechanisms of oxidative stress in schizophrenic patients are not fully understood. In the present study, we investigated
the effect of elevated level of homocysteine (Hcys) on some parameters of oxidative stress, namely thiobarbituric acid reactive
substances (TBARS), an index of lipid peroxidation in plasma, the level of carbonyl groups in plasma proteins, as well as
the amount of 3-nitrotyrosine in plasma proteins isolated from schizophrenic patients. Patients hospitalised in I and II Psychiatric
Department of Medical University in Lodz, Poland were interviewed with special questionnaire (treatment, course of diseases,
dyskinesis and other EPS). According to DSM-IV criteria all patients had diagnosis of paranoid type. They were treated with
antipsychotic drugs (clozapine, risperidone, olanzapine). Mean time of schizophrenia duration was about 5 years. High-performance
liquid chromatography was used to analyse the total level of homocysteine in plasma. Levels of carbonyl groups and 3-nitrotyrosine
residues in plasma proteins were measured by ELISA and a competition ELISA, respectively. The lipid peroxidation in plasma
was measured by the level of TBARS. Our results showed that in schizophrenic patients the amount of homocysteine in plasma
was higher in comparison with the control group. We also observed a statistically increased level of biomarkers of oxidative/nitrative
stress such as carbonyl groups or 3-nitrotyrosine in plasma proteins from schizophrenic patients. Moreover, our experiments
indicate that the correlation between the increased amount of homocysteine and the oxidative stress exists. Considering the
data presented in this study, we suggest that the elevated Hcys in schizophrenic patients may stimulate the oxidative stress. 相似文献
127.
Dziadziuszko H Kumirska J Muża S Czerwicka M Lubecka EA Stepnowski P Kunikowska D 《FEMS microbiology letters》2012,326(1):55-61
Salmonella Dakar and Salmonella Telaviv bacteria belong to serogroup O:28, which represents 107 serovars and possesses only the epitope O28. Salmonella Telaviv has the subfactors O28(1) and O28(2) , whereas S. Dakar has O28(1) and O28(3) . So far, only limited serological and immunological information for this serogroup is available in the literature. Knowledge of the structures of their O-polysaccharides and the immunochemical investigations performed in this work allowed to reveal the nature of subfactor O28(1) as attributed to the presence of 3-linked (or 3,4-disubstituted) α-d-GalpNAc in the main chains of S. Dakar and S. Telaviv O-polysaccharides. An explanation for the cross-reactions between Salmonella enterica O28 O-antigens and other Salmonella O-polysaccharides and their structural similarity to Escherichia coli O-serogroups is also given. 相似文献
128.
Wiejak J Dunlop J Stoyle C Lappin G McIlroy A Pediani JD Gao S Yarwood SJ 《Cellular signalling》2012,24(8):1690-1699
129.
130.
While the essential role of episomal par loci in plasmid DNA partitioning has long been appreciated, the function of chromosomally encoded par loci is less clear. The chromosomal parA-parB genes are conserved throughout the bacterial kingdom and encode proteins homologous to those of the plasmidic Type I active partitioning systems. The third conserved element, the centromere-like sequence called parS, occurs in several copies in the chromosome. Recent studies show that the ParA-ParB-parS system is a key player of a mitosis-like process ensuring proper intracellular localization of certain chromosomal regions such as oriC domain and their active and directed segregation. Moreover, the chromosomal par systems link chromosome segregation with initiation of DNA replication and the cell cycle. 相似文献