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1.
本文记述了中国半翅目仰蝽科一新种:突顶小仰蝽Anisops protracta sp. nov. 及一新记录:南小仰蝽A. exigera Horvath。对于新种进行了描述,并附特征插图8幅。 相似文献
2.
本文记述了寄生于淡水鱼类的棘口科吸虫的一个新种——淮河达氏吸虫Ditetziella huaiheeniss sp.nov.模式标本采自安徽省淮河的女山湖地区黄颡鱼的肠道。 相似文献
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Dolotov OV Zolotarev IuA Dorokhova EM Andreeva LA Alfeeva LIu Grivennikov IA Miasoedov NF 《Bioorganicheskaia khimiia》2004,30(3):241-246
The binding characteristics of the peptide Semax (Met-Glu-His-Phe-Pro-Gly-Pro) to plasma membranes of basal nuclei of the rat forebrain and the dynamics of its degradation during its incubation with these membranes were studied. Binding of the homogeneously labeled [G-3H]Semax was shown to be time-dependent, specific, and reversible. Specific binding of the heptapeptide depended on calcium ions and was characterized by the dissociation constant of the ligand-receptor complex Kd = 2.41 +/- 1.02 x 10(-9) M and by the concentration of binding sites Bmax = 33.5 +/- 7.9 x 10(-15) mol/mg of protein. A method of studying Semax biodegradation in the presence of plasma membranes of rat brain was developed. It is based on the use of the peptide homogeneously labeled with tritium and on an HPLC analysis with UV detection at 220 and 254 nm of the peptide fragments formed. The half-life of Semax in the presence of the plasma membranes was demonstrated to be longer than 1 h. Dipeptidylaminopeptidases are considered to be the main enzymes responsible for its biodegradation; they successively cleave Semax to the HFPGP pentapeptide and the PGP tripeptide. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru. 相似文献
4.
微生物可以利用工业废弃物产生氢气,其产氢机理可以分成两种:光合产氢和发酵产氢。前者利用光能,后者利用代谢过程中产生的电子,分解有机物产氢。氢酶是产氢过程中的关键酶,催化氢的氧化或质子的还原。氢酶主要有[NiFe]氢酶和[Fe]氢酶两种,具有不同的结构,但催化机理是相似的。本文主要综述产氢微生物的种类、微生物产氢代谢途径和关键酶催化机理,并展望微生物产氢研究的发展方向。 相似文献
5.
Zolotarev IuA Dadaian AK Dolotov OV Kozik VS Kost NV Sokolov OIu Dorokhova EM Meshavkin VK Inozemtseva LS Gabaeva MV Andreeva LA Alfeeva LIu Pavlov TS Badmaeva KE Badmaeva SE Bakaeva ZV Kopylova GN Samonina GE Vas'kovskiĭ BV Grivennikov IA Zozulia AA Miasoedov NF 《Bioorganicheskaia khimiia》2006,32(2):183-191
Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50-150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with spillover tritium. The distribution of the isotope label among all amino acid residues of these peptides allows the simultaneous determination of practically all possible products of their enzymatic hydrolysis. The developed analytical method includes extraction of tritium-labeled peptides from organism tissues and chromatographic isolation of individual labeled peptides from the mixture of degradation products. The concentrations of a peptide under study and the products of its biodegradation were calculated from the results of liquid scintillation counting. This approach was used for studying the pathways of biodegradation of the heptapeptide TKPRPGP (Selank) and the tripeptide PGP in blood plasma. The pharmacokinetics of Selank, an anxiolytic peptide, was also studied in brain tissues using the intranasal in vivo administration of this peptide. The concentrations of labeled peptides were determined, and the pentapeptide TKPRP, tripeptide TKP, and dipeptides RP and GP were shown to be the major products of Selank biodegradation. The study of the biodegradation of the heptapeptide MEHFPGP (Semax) in the presence of nerve cells showed that the major products of its biodegradation are the pentapeptide HFPGP and tripeptide PGP. The enkephalinase activity of blood plasma was studied with the use of evenly tritium-labeled [Leu]enkephalin. A high inhibitory effect of Semax on blood plasma enkephalinases was shown to arise from its action on aminopeptidases. The method, based on the use of evenly tritium-labeled peptides, allows the determination of peptide concentrations and the activity of enzymes involved in their degradation on a tg scale of biological samples both in vitro and in vivo. 相似文献
6.
Shevchenko KV Nagaev IIu Alfeeva LIu Andreeva LA Kamenskiĭ AA Levitskaia NG Shevchenko VP Grivennikov IA Miasoedov NF 《Bioorganicheskaia khimiia》2006,32(1):64-70
The radioactive peptide analogue Semax corresponding to the ACTH(4-10) sequence (Met-Glu-His-Phe-Pro-Gly-Pro) with a molar radioactivity of 56 Ci/mmol labeled with tritium at the C-terminal Pro was prepared. The labeled peptide was used for studying the kinetics of Semax penetration into rat brain and blood after its intranasal administration (50 microg/kg, 20 microl of solution) to nonbred white rats of body mass 200-250 g. It was demonstrated that 0.093% of the total introduced radioactivity per gram can be found in the rat brain 2 min after the administration, 80% of this radioactivity belonged to Semax, and the rest, to its metabolites. The peptide undergoes rapid enzymatic degradation, with the tripeptide Pro-Gly-Pro prevailing in biological samples relative to the total content of Semax and its metabolites. 相似文献
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Yu. A. Zolotarev A. K. Dadayan O. V. Dolotov V. S. Kozik N. V. Kost O. Yu. Sokolov E. M. Dorokhova V. K. Meshavkin L. S. Inozemtseva M. V. Gabaeva L. A. Andreeva L. Yu. Alfeeva T. S. Pavlov K. E. Badmaeva S. E. Badmaeva Z. V. Bakaeva G. N. Kopylova G. E. Samonina B. V. Vaskovsky I. A. Grivennikov A. A. Zozulya N. F. Myasoedov 《Russian Journal of Bioorganic Chemistry》2006,32(2):166-173
Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50–150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with spillover tritium. The distribution of the isotope label among all amino acid residues of these peptides allows the simultaneous determination of practically all possible products of their enzymatic hydrolysis. The developed analytical method includes extraction of tritium-labeled peptides from organism tissues and chromatographic isolation of individual labeled peptides from the mixture of degradation products. The concentrations of a peptide under study and the products of its biodegradation were calculated from the results of liquid scintillation counting. This approach was used for studying the pathways of biodegradation of the heptapeptide TKPRPGP (Selank) and the tripeptide PGP in blood plasma. The pharmacokinetics of Selank, an anxiolytic peptide, was also studied in brain tissues using the intranasal in vivo administration of this peptide. The concentrations of labeled peptides were determined, and the pentapeptide TKPRP, tripeptide TKP, and dipeptides RP and GP were shown to be the major products of Selank biodegradation. The study of the biodegradation of the heptapeptide MEHFPGP (Semax) in the presence of nerve cells showed that the major products of its biodegradation are the pentapeptide HFPGP and tripeptide PGP. The enkephalinase activity of blood plasma was studied with the use of evenly tritium labeled [Leu]enkephalin. A high inhibitory effect of Semax on blood plasma enkephalinases was shown to arise from its action on aminopeptidases. The method, based on the use of evenly tritium-labeled peptides, allows the determination of peptide concentrations and the activity of enzymes involved in their degradation on a μg scale of biological samples both in vitro and in vivo. 相似文献
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Zolotarev YA Dolotov OV Inozemtseva LS Dadayan AK Dorokhova EM Andreeva LA Alfeeva LY Grivennikov IA Myasoedov NF 《Amino acids》2006,30(4):403-408
Summary. Here a new approach of the elucidation of paths of proteolytic biodegradation of physiologically active peptides, based on
the use of a peptide with isotopic label at all amino acid residues and the enrichment of HPLC samples with unlabeled peptide
fragments in UV-detectable concentration, has been proposed. The method has been applied for the investigation of degradation
dynamics of the neuroactive heptapeptide MEHFPGP (Semax) in the presence of plasma membranes, and cultures of glial and neuronal
cells obtained from the rat basal forebrain. The splitting away of ME and GP, and formation of pentapeptides are the predominant
processes in the presence of all tested objects, whereas the difference in patterns of resulting peptide products for glial
and neuronal cells has been detected. In conclusion, the approach applied allows analyzing physiologically active peptide
concentrations in biological tissues and degradation pathways of peptides in the presence of targets of their action. 相似文献