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1.
The bone marrow myelopeptide MP-2 (Leu-Val-Val-Tyr-Pro-Trp), exhibiting antitumor activity, and its retro-analogue (Trp-Pro-Tyr-Val-Val-Leu) were synthesized, and their properties were studied. The in vitro and in vivo activities of retro-MP-2 were comparable with those of MP-2. Both peptides equally restored the functional activity of T-lymphocytes inhibited by toxins released by HL-60 cells and inhibited by 70-82% the growth of various types of transplantable solid tumors: Ca-755 adenocarcinoma of the mammary gland, Lewis adenocarcinoma of the lung, and S180 sarcoma. The positions and intensities of the Cotton effects in CD spectra of the MP-2 peptide and its retro-analogue in various solvents are almost indistinguishable. The positions of extrema and integral intensities of the amide I and amide A bands in IR spectra of both peptides were practically identical. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 3; see also http://www.maik.ru.  相似文献   

2.
In this study we examined the conformation and side chain environments of angiotensins I, II, III, and [Sar1-Ile5-Ala8]angiotensin II using laser Raman spectroscopy. The positions of the amide I bands for all four peptides were found between 1664 and 1673 cm?1. D2O exchange studies confirmed the positions of the amide I and amide III bands. The positions of the amide I bands for all the angiotensins were found at approximately 1665 cm?1 and the amide III bands were all located between 1265 and 1278 cm?1. From the positions and intensities of the amide I and III bands we concluded that all peptides share the same overall conformation consisting of β-turn structure. Spectral analysis indicated that although the spectra for all the peptides were qualitatively identical there was evidence that the angiotensin conformations were more flexible in the aqueous phase than the solid phase. Examination of the 850830 cm?1 tyrosine doublet suggested that the tyrosine residue in the peptides is exposed to the solvent environment and becomes more exposed as the peptide length is decreased. Therefore, there are some localized conformational differences among the angiotensins. The conformational data yielded by this study leads us to conclude that the various biological properties ascribed to the angiotensins are not due to different conformations of the peptides. The biological differences could perhaps be attributed to localized interactions of the individual amino acid residues with themselves and with the hormone receptors.  相似文献   

3.
Allozyme spectra of peroxidase, esterase, superoxid dismutase, tyrosinase, alcohol dehydrogenase, lactate dehydrogenase, and acid phosphatase were examined in populations of sexual (Taraxacum serotinum and Pilosella echioides) and apomictic (T. officinale and P. officinarum) plant species. The heterozygosity in these populations (0.455–0.620) proved to be considerably higher than the average level characteristic of plant populations (0.058–0.185). The populations examined did not differ in the mean phenotype number , i.e., they exhibited the same diversity (3.188–3.380). The proportion of rare phenotypes h also did not differ between the sexual and apomictic species of the same genus, whereas this parameter in the Pilosella populations (0.150–0.174) was significantly higher than in the Taraxacum ones (0.093–0.114). The populations were characterized by numerous isozyme spectra (more than 11 per populations) and displayed multiple allelism (the mean allele frequency was 3.63–4.38 per locus). They exhibited a high percentage of rare (occurring at a frequency lower than 5%) spectra (35–80%). This indicates that agamic complexes, to which these populations belong, may have a more complicated genetic structure of both apomictic and sexual populations than the species that do not belong to agamic complexes.Translated from Genetika, Vol. 41, No. 2, 2005, pp. 203–215.Original Russian Text Copyright © 2005 by Kashin, Anfalov, Demochko.  相似文献   

4.
Theoretical conformational analysis was used to study the spatial structure and conformational properties of myelopeptides, bone-marrow peptide mediators. The low-energy conformations of three hexapeptides MP-1 (Phe-Leu-Gly-Phe-Pro-Thr), MP-2 (Leu-Val-Val-Tyr-Pro-Trp), and MP-3 (Leu-Val-Cys-Tyr-Pro-Gln) were found, the values of dihedral angles of the backbone and side chains of the amino acid residues con-stituting these peptides were determined, and the energies of intra- and interresidual interactions were estimated.Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 1, 2005, pp. 31–38.Original Russian Text Copyright © 2005 by Akhmedov, Ismailova, Abbasli, Akhmedov, Godjaev.  相似文献   

5.
A member of the GGNG peptide family was isolated from Hirudo nipponia (leech). GGNG peptides had only been isolated previously from earthworms. The C-terminus structure of the leech peptide, LEP (leech excitatory peptide), was –Gly–Gly–Asn–amide, while that of the earthworm peptides, EEP (earthworm excitatory peptide), was –Gly–Gly–Asn–Gly. LEP exerted 1000-fold more potent activities on leech gut than did EEP-2. On the other hand, EEP-2 was 1000-fold more potent than LEP on the crop-gizzard of the earthworm. Analog peptides of LEP and EEP-2 were synthesized, and the myoactive potency of each analog on the leech and earthworm tissues was compared.  相似文献   

6.
Resonances in the two-dimensional 1H NMR spectra of a weak toxin (WTX) from the venom of cobra Naja kaouthiafor all 65 amino acid residues were assigned. The amino acid sequence of WTX, determined by the sequential assignment of spin systems, was found to be similar to that of the CM-9a toxin from the N. kaouthiavenom. Unlike CM-9a, WTX contains an additional Trp36 residue; Lys50 and Tyr52 are interchanged; and there is a Thr residue in place of Arg2. For some residues of WTX, the presence of two components of approximately equal intensities in the spectra was shown, which is explained by the conformational heterogeneity of the polypeptide owing to the cistransisomerization of the peptide bond Arg32–Pro33. The data (contacts of the nuclear Overhauser effect, constants of spin–spin coupling of protons, and rates of exchange of amide protons for deuterium of the solvent) made it possible to determine the secondary structure of two forms of WTX, which is characterized by the presence of two antiparallel -sheets, one of which consists of two strands (regions 1–5 and 13–17) and the other, of three strands (regions 23–28, 38–43, and 55–59).  相似文献   

7.
POMC-derived peptides and mRNA have been identified in heart tissue, although POMC processing has not been fully characterized. In the present study, we found that β-lipotropin and ACTH were localized in rat heart, although they were almost entirely converted to β-endorphin- and α-MSH-related peptides. Ion exchange HPLC analysis revealed that β-endorphin(1–31) was further processed to α-N-acetyl-β-endorphin(1–31), which comprised 35.9 ± 0.1% of total immunoreactivity, and smaller amounts of β-endorphin(1–27), β-endorphin(1–26), and their α-N-acetylated derivatives. The predominant α-MSH immunoreactive peptides coeluted with α-MSH and N,O-diacetyl-α-MSH by reverse-phase HPLC, although small amounts of ACTH(1–13)-NH2 were also present. Thus, multiple forms of β-endorphin and α-MSH are localized in rat heart. β-Endorphin(1–31) is a minor constituent, however, indicating that nonopioid β-endorphin peptides predominate.  相似文献   

8.
Uraline, a new norditerpenoid alkaloid, was isolated from aerial parts of Delphinium uralense. The structure of 1α,7,8-trihydroxy-6β,14α,16β-trimethoxy-18-N-(2-methyl)succinylanthranoyloxyaconane was ascribed to the new compound on the basis of 1H and 13C NMR, IR, and mass spectra. The known alkaloids methyllycaconitine and delcorine were also isolated from the plant.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 4, 2005, pp. 425–429.Original Russian Text Copyright © 2005 by Gabbasov, Tsyrlina, Spirikhin, Danilov, Yunusov.  相似文献   

9.
Two extracellular oxidases (laccases) were isolated from the extracellular fluid of the fungus Panus (Lentinus) tigrinus cultivated in low-nitrogen medium supplemented with birch sawdust. The enzymes were purified by successive chromatography on columns with TEAE-cellulose and DEAE-Toyopearl 650M. Both oxidases catalyze oxidation of pyrocatechol and ABTS. Moreover, oxidase 1 also catalyzes oxidation of guaiacol, o-phenylenediamine, and syringaldazine. The enzymes have identical pH (7.0) and temperature (60–65°C) optimums. Absorption spectra of the oxidases differ from the spectra of typical “blue” laccases and are similar to the spectrum of yellow oxidase.__________Translated from Biokhimiya, Vol. 70, No. 6, 2005, pp. 850–854.Original Russian Text Copyright © 2005 by Cadimaliev, Revin, Atykyan, Samuilov.  相似文献   

10.
The effect of neuropeptide thyrotropin-releasing hormone (TRH) and its synthetic analogue digipramine on certain indices of blood coagulation and fibrinolysis were studied in vitro and in vivo. The peptides added to the pool of normal rat plasma at 10−10 to 10−3 M increased the procoagulant activity but had virtually no effect on fibrinolysis. Intravenous administration of TRH and digipramine increased the procoagulant activity of the blood and platelet aggregation but decreased fibrinolysis; digipramine had a more pronounced effect on the coagulation potential of the blood and a less pronounced effect on fibrinolytic indices as compared to TRH. Intranasal administration of the peptides did not change the pattern of their effect on indices of hemostasis although the effects became less pronounced.__________Translated from Izvestiya Akademii Nauk, Seriya Biologicheskaya, No. 3, 2005, pp. 311–315.Original Russian Text Copyright © 2005 by Grigorjeva, Golubeva.  相似文献   

11.
1H NMR spectroscopy was applied to study the reactions of cis-[Pd(L)(H2O)2]2+ complexes (L is en, pic and dpa) with the N-acetylated tripeptides L-methionylglycylglycine, MeCOMet–Gly–Gly, and glycyl–L-methionyl–glycine, MeCOGly–Met–Gly. All reactions were performed in the pH range 2.0–2.5 with equimolar amounts of the cis-[Pd(L)(H2O)2]2+ complex and the tripeptide at 60 °C. The hydrolytic reactions of the cis-[Pd(en)(H2O)2]2+, cis-[Pd(pic)(H2O)2]2+ and cis-[Pd(dpa)(H2O)2]2+ complexes with MeCOMet–Gly–Gly were regioselective and only the amide bond involving the carboxylic group of methionine was cleaved. However, in the reactions of these three Pd(II) complexes with MeCOGly–Met–Gly, two amide bonds, Met–Gly and MeCO–Gly, were cleaved. From UV–Vis spectrophotometry studies, it was found that the rate-determining step of these hydrolytic reactions is the monodentate coordination of the corresponding Pd(II) complex to the sulfur atom of the methionine side chain. The rate of the cleavage of these amide bonds is dependent on the nature of the bidentate coordinated diamine ligand L (en > pic > dpa). The hydrolytic reaction of cis-[Pd(L)(H2O)2]2+-type complexes with MeCOMet–Gly–Gly, containing the methionine side chain in the terminal position of the peptide, is regioselective while in the reaction of these Pd(II) complexes with MeCOGly–Met–Gly, none selective cleavage of the peptide occurs. This study contributes to a better understanding of the selective cleavage of methionine-containing peptides employing palladium(II) complexes as catalysts.  相似文献   

12.
Spectral and photochemical properties were analyzed on intact chloroplasts and pigment-protein complexes isolated with gel electrophoresis from pea (Pisum sativum L.) leaves of parental variety Torsdag and of chlorophyll-deficient mutants chlorotica 2004 and 2014. Measurements of chlorophyll absorption and fluorescence spectra and of second derivative low-temperature (–196°C) spectra clarified exact positions of fluorescence maxima and revealed the chlorophyll forms of individual complexes in samples investigated. The chlorotica 2004 mutant, whose hybrids yield the heterosis effect, was characterized by the decreased accumulation of chlorophyll forms absorbing at 690, 697, and 708 nm, known to constitute the core antenna in the vicinity of photosystem I (PSI) reaction center. In the chlorotica 2014 mutant, whose hybrids are low productive, the interaction between PSI and PSII complexes was weakened, but no other difference from the parental variety was observed. The analysis of PSI and PSII photochemical activities, as well as estimates of light-harvesting antenna size and the number of reaction centers revealed that the chlorotica 2004 mutant is deficient in the number of PSI reaction centers by a factor of 1.7. This deficiency resulted from the mutation-induced disorder in biosynthesis of chlorophyll a-protein complex of PSI. It appears that gene interactions between the 2004 mutant and the parental variety Torsdag enhance the functional and metabolic activity of leaves in their hybrids, thereby yielding the heterosis effect.Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 172–183.Original Russian Text Copyright © 2005 by Ladygin, Vaishlya.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

13.
Lipid A was obtained in a high yield (27%) by the hydrolysis of lipopolysaccharide from the marine gamma proteobacterium Marinomonas communis ATCC 27118T with 1% AcOH. Using chemical analysis and 1D and 2D NMR spectroscopic and fast atom bombardment mass spectrometric methods, it was shown to be β-1′,6-linked D-glucosaminobiose 1-phosphate acylated with (R)-3-dodecanoyl- or (R)-3-decanoyloxydecanoic acid, (R)-3-{(R)-3-hydroxydecanoyloxy)]decanoic acid and (R)-3-hydroxydecanoic acid at the C2, C2′ and C3 positions, respectively. Uncommon structural peculiarities (a low acylation and phosphorylation degree) of the M .communis lipid A in comparison with those of terrestrial bacteria may be of pharmacological interest. The potential physiological meaning of this lipid A and compounds of similar structure are discussed.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 4, 2005, pp. 404–413.Original Russian Text Copyright © 2005 by Vorob’eva, A. Dmitrenok, P. Dmitrenok, Isakov, Krasikova, Solov’eva.The article was translated by the authors.  相似文献   

14.
Summary The effects of selective deuteration on calculated NOESY intensities have been analyzed for the structure of theE. coli trp aporepressor, a 25 kDa protein. It is shown that selectively deuteratedtrp aporepressor proteins display larger calculated NOESY intensities than those for the same interproton distances in the natural abundance protein. The relatively larger magnetization transfer is demonstrated by a comparison of the NOE build-up curves for specific proton pairs, and for the calculated NOE intensities of short-range NOEs to backbone amide protons. This increase in intensity is especially pronounced for the NH1–NH1+1 cross peaks in the -helical regions, and particularly for amide protons of two sequential deuterated residues. The effect is shown to be further intensified for longer mixing times. It is also shown that in all cases, each amide proton exhibits stronger NOEs to its own side chain, with an enhanced effect for deuterated derivatives. This theoretical analysis demonstrates that an evaluation of the relative NOE intensities for different selectively deuterated analogs may be an important tool in assigning NMR spectra of large proteins. These results also serve as a guide for the interpretation of NOEs in terms of distances for structure calculations based on data using selectively deuterated proteins.  相似文献   

15.
Using nucleotide sequences from jumping and linking NotI libraries of human chromosome 3, 94 NotI-STS markers for 72 individual NotI clones were developed. The positions of the NotI-STS markers and their order on the chromosome were determined by a combination of RH-mapping (our data), contig mapping, cytogenetic mapping, and in silico mapping. Comparison of NotI-STS DNAs with human genome sequences revealed two gaps in the regions 3p21.33 (marker NL1-256) and 3p21.31 (NL3-005), and a segmental duplication. Identical DNA fragments were found in the regions 12q and 3p22–21.33 (marker NL3-007). In the 3q28–q29 region (marker NLM-084), a fragment was detected whose identical copies were also present on chromosomes 1, 2, 15, and 19. For 69 NotI-STSs, significant homologies to nucleotide sequences of 70 genes and 2 cDNAs were detected (with homologies in NotI-STS 5′- and 3′-terminal sequences being taken into account). An association between NotI-STSs and genes is confirmed by a strong correlation between the density distributions of genes and NotI-STS markers on the map of human chromosome 3. Our results indicate that the NotI map may be regarded as a gene map of human chromosome 3. Thus, NotI-STSs are applicable as gene markers.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 4, 2005, pp. 687–701.Original Russian Text Copyright © 2005 by Sulimova, Rakhmanaliev, Klimov, Kompaniytsev, Udina, Zabarovsky, Kisselev.  相似文献   

16.
Acid extracts of rat anterior pituitary cells and cell-derived culture media were shown to contain three forms of β-endorphin immunoreactive peptides, corresponding in molecular size to the prohormone pro-opiomelanocortin (POMC), β-lipotropin and 3.5 kDa β-endorphin, and essentially two forms of adrenocorticotropin (ACTH) immunoreactivity, representing a 20 kDa intermediate fragment and 4.5 kDa ACTH. Under basal conditions the intracellular peptides contained a high proportion of the bioactive forms of β-endorphin and ACTH whereas the extracellular peptides contained a higher proportion of the inactive precursors. When the cells were incubated for 3 h in the presence of 10−8 M CRF, the levels of intracellular β-endorphin and ACTH immunoreactivity were reduced by 15–30% and there was a 4–5-fold increase in the level of the secreted peptides; furthermore, unlike the peptides released under basal conditions, the peptides secreted under the influence of CRF contained much higher proportions of 4.5 kDa ACTH and 3.5 kDa β-endorphin, reflecting the intracellular patterns of these peptides. Similar results were obtained when secretion was stimulated by 10−7 M epinephrine, which produced a 2-fold increase in peptide release. In the presence of 10−6 M dexamethasone the basal secretion of ACTH and β-endorphin related peptides, and the intracellular levels of these peptides, remained unaltered. The results point to the existence of different intracellular compartments from which peptides at different states of maturation can be released selectively.β-EndorphinACTHPituitary cell cultureProcessingCRFEpinephrine  相似文献   

17.
The1H nuclear magnetic resonance (NMR) spectra of angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe) and five of its octapeptide analogs as well as angiotensin I (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu) and angiotensin III (Arg-Val-Tyr-Ile-His-Pro-Phe) in aqueous solutions (90% H2O/10% D2O) were completely assigned by two-dimensional COSY and ROESY experiments. All of the peptides give rise to two distinct sets of signals. The minor set accounts for about 5% of the total population belowpH 5.5 and increases to 12–20% aroundpH 7.0. The two sets of signals result from acis-trans isomerization of the His-Pro peptide bond with the major resonances arising from thetrans isomer. One analog in which the Pro is replaced with a D-Pro displays a very different isomerization behavior. The measured coupling constants JNH-CH, the temperature dependence of the amide proton shifts and the relative intensities of the intraresidue and sequential NH-CH ROEs, are all indicative of an extended backbone conformation for ANGII. However, some evidence for the existence of conformers with local structure involving preferred sidechain positions for the Tyr, His, Phe, and the carboxyl group of the Phe was found, particularly in the ROESY andpH-titration experiments. Moreover,pH effects and the unusual amide exchange behavior of the Arg NH suggests the presence of interactions between the Asp and Arg sidechains of ANGII. At low temperatures the Arg guanidinium NH2 protons were detected as two broad peaks which are related by sizeable exchange peaks in ROESY experiments. This behavior could be useful as a general probe for the study of Arg sidechain mobility and accessibility in other peptides and proteinsPreliminary results of this work have been presented at the XIIth International Conference on Magnetic Resonance in Biological Systems in abstract form (1988).  相似文献   

18.
To study the evolution of the polymeric β-fructosidase (invertase) genes (SUC) of yeasts Saccharomyces, new SUC gene of S. cariocanus was cloned and sequenced and the nucleotide and amino acid sequences were compared for all known β-fructosidases of Saccharomyces species. The proteins showed 90–97% homology. The most divergent was S. bayanus β-fructosidase. The results testified again to high conservation of yeast β-fructosidases. Transitions C-T prevail in the total spectrum of nucleotide substitutions observed in the coding regions of the SUC genes; most of these transitions are in the third codon position and cause no changes in the amino acid sequences of the encoded proteins. The six Saccharomyces species each carry one (probably, non-telomeric) β-fructosidase gene. SUC is on chromosome IX in S. cerevisiae, S. bayanus, S. kudriavzevii, S. mikatae, and S. paradoxus and in a translocation region on chromosome XV in S. cariocanus.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 3, 2005, pp. 413–419.Original Russian Text Copyright © 2005 by Korshunova, Naumova, Naumov.  相似文献   

19.
The ability of metabolites contained in culture liquid of 62 strains of marine fungi to affect the activity of two digestive enzymes of marine mollusks—endo-1,3-β-D-glucanase of Spisula sachalinensis and β-D-glucosidase of Littorina kurila—was studied. It was found that 66 and 71% of specimens activated, 18 and 7% inhibited, and 16 and 22% did not affect the activity of endo-1,3-β-D-glucanase and β-D-glucosidase, respectively. It is demonstrated that the metabolites of brown algae and marine sponges can be used for a targeted regulation of enzyme biosynthesis by marine fungi. The protein inhibitor of endo-1,3-β -D-glucanases isolated from the brown alga Laminaria cichorioides blocked the biosynthesis of almost all O-glycosylhydrolases in five strains of marine fungi studied. The presence in culture medium of halistanol sulfate from the marine sponge of the family Halichondriidae either did not affect or activated the biosynthesis of enzymes involved in carbohydrate metabolism by marine fungi.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 4, 2005, pp. 402–408.Original Russian Text Copyright © 2005 by Verigina, Burtseva, Ermakova, Sova, Pivkin, Zvyagintseva.  相似文献   

20.
In this paper, the reactions of bovine insulin and small peptides, such as actin binding domain of thymosin β4 and Growth Hormone Releasing Factor (GRF 1–29 amino acids) with diisopropyloxyphosphite (DIPPH) and dimethyloxyphosphite (DMPH) were studied by modified Todd reaction. The MALDI-TOF or ESI-MS results showed that lysine, histidine and arginine residues in insulin could be phosphorylated under the water/ethanol system. The N,N,N-diisopropyloxyphosphorylated insulin analogues were characterized using MALDI-TOF and 31P NMR. These insulin analogues with different phosphorylation degree were separated and identified through LC-ESI-MS. In addition, circular dichroism (CD) spectra showed that the conformation of N,N,N-dimethyloxyphosphorylated insulin were only changed a little, whereas, that of N,N,N-diisopropyloxyphosphorylated insulin was changed completely.  相似文献   

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