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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
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3.
Strel'tsov S. A. Grokhovskii S. L. Kudelina I. A. Oleinikov V. A. Zhuze A. L. 《Molecular Biology》2001,35(3):365-373
Behavior of topotecan, DNA topoisomerase I inhibitor, was studied in aqueous solutions by optical methods. Topotecan absorption spectra were recorded in the pH range 0.5–11.5 and its pKa were determined. Quantum chemical calculations were made for all charge states of the topotecan molecule in lactone and carboxylate form. The calculated absorption maxima agree well with the experimental data. Protonation of the topotecan D ring (pKa 3.6) was revealed. Comparison of experimental and calculated data showed topotecan structure with a proton at the oxygen atom at C16a rather than N4 to be the most preferable. Topotecan molecules were shown to form dimers at concentrations above 10–5M. Topotecan dimerization is accompanied by an increase in the pKa of hydroxy group of the A ring from 6.5 ([TPT] = 10–6M) to 7.1 ([TPT] = 10–4M), which indicates participation of this group in dimer stabilization, perhaps due to intermolecular hydrogen bonding with N1 of the B ring of a neighboring molecule. Probable dimer structures were proposed. The topotecan dimerization constant was determined, K = (4.0 ± 0.7)·103M–1. 相似文献
4.
Shenkarev ZO Paramonov AS Nadezhdin KD Bocharov EV Kudelina IA Skladnev DA Tagaev AA Yakimenko ZA Ovchinnikova TV Arseniev AS 《化学与生物多样性》2007,4(6):1219-1242
Antiamoebin I (Aam-I) is a membrane-active peptaibol antibiotic isolated from fungal species belonging to the genera Cephalosporium, Emericellopsis, Gliocladium, and Stilbella. Antiamoebin I has the amino acid sequence: Ac-Phe(1)-Aib-Aib-Aib-Iva-Gly-Leu-Aib(8)-Aib-Hyp-Gln-Iva-Hyp-Aib-Pro-Phl(16). By using the uniformly (13)C,(15)N-labeled sample of Aam-I, the set of conformationally dependent J couplings and (3h)J(NC) couplings through H-bonds were measured. Analysis of these data along with the data on magnetic nonequivalence of the (13)C(beta) nuclei (Deltadelta((13)C(beta))) in Aib and Iva residues allowed us to draw the univocal conclusion that the N-terminal part (Phe(1)-Gly(6)) of Aam-I in MeOH solution is in fast exchange between the right-handed and left-handed 3(10)-helical conformations, with an approximately equal population of both states. An additional conformational exchange process was found at the Aib(8) residue. The (15)N-NMR-relaxation and CD-spectroscopy measurements confirmed these findings. Molecular modeling and Monte Carlo simulations revealed that both exchange processes are correlated and coupled with significant hinge-bending motions around the Aib(8) residue. Our results explain relatively low activity of Aam-I with respect to other 15-amino acid residue peptaibols (for example, zervamicin) in functional and biological tests. The high dynamic 'propensity' possibly prevents both initial binding of the antiamoebin to the membrane and subsequent formation of stable ionic channels according to the barrel-stave mechanism. 相似文献
5.
Vasilevskiĭ AA Kozlov SA Zhmak MN Kudelina IA Dubovskiĭ PV Shaturskiĭ OIa Arsen'ev AS Grishin EV 《Bioorganicheskaia khimiia》2007,33(4):405-412
Analogues of latarcins Ltc1 and Ltc3b, antimicrobial peptides from the venom of the Central Asian spider Lachesana tarabaevi capable of formation of amphiphilic structures in membranes without involvement of disulfide bonds, were synthesized. The amino acid sequences of the analogues correspond to immature forms of these peptides, each of them containing an additional C-terminal amino acid residue. It is concluded from the study of the biological activity of the synthesized peptides that the posttranslational C-terminal amidation of Ltc3b is a functionally important modification that ensures a high activity of the mature peptide. The lipid composition was shown to affect the interaction of synthesized peptides with artificial membranes. The analogue of Ltc3b manifested the highest activity on cholesterol-containing membranes. The mechanism of action of the studied antimicrobial peptides on membranes is discussed. 相似文献
6.
TANATIN BI 《Mikrobiologiia》1951,20(6):506-511
7.
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S A Strel'tsov S L Grokhovski? I A Kudelina V A Ole?nikov A L Zhuze 《Molekuliarnaia biologiia》2001,35(3):432-441
Behavior of topotecan, DNA topoisomerase I inhibitor, was studied in aqueous solutions by optical methods. Topotecan absorption spectra were recorded in the pH range 0.5-11.5 and its pKa were determined. Quantum chemical calculations were made for all charge states of the topotecan molecule in lactone and carboxylate form. The calculated absorption maxima agree well with the experimental data. Protonation of the topotecan D ring (pKa = 3.6) was revealed. Comparison of experimental and calculated data showed topotecan structure with a proton at the oxygen atom at C16a rather than N4 to be the most preferable. Topotecan molecules were shown to form dimers at concentrations above 10(-5) M. Topotecan dimerization is accompanied by an increase in the pKa of hydroxy group of the A ring from 6.5 ([TPT] = 10(-6) M) to 7.1 ([TPT] = 10(-4) M), which indicates participation of this group in dimer stabilization, perhaps due to intermolecular hydrogen bonding with N1 of the B ring of a neighboring molecule. Probable dimer structures were proposed. The topotecan dimerization constant was determined, K = (4.0 +/- 0.7) x 10(3) M-1. 相似文献
9.
ANDRÉIA SILVA FLORES RÉA M. CORRÊA ELIANA R. FORNI-MARTINS ANA M. G. AZEVEDO TOZZI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):271-277
Chromosome numbers were counted for 23 species of Crotalaria native to Brazil. Among these data there were new counts for 15 taxa, and some confirmed previous reports or represented numbers that were different from those cited previously. The chromosome numbers most frequently found were 2 n = 16 and 2 n = 32. Only C. incana L. had 2 n = 14 and C. tweediana Benth. had 2 n = 54. The counts 2 n = 32 and 54 were found in species of section Calycinae and 2 n = 16 and 14 in species of section Chrysocalycinae . The data revealed the importance of chromosomal parameters in the characterization of sections Calycinae and Chrysocalycinae in Brazil. We discuss the systematic significance and evolutionary aspects for the genus, comparing the results with the two sections that are native in Brazil. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 271–277. 相似文献
10.
Ricci GC De Souza-Kaneshima AM Felismino MF Mendes-Bonato AB Pagliarini MS Do Valle CB 《Journal of genetics》2011,90(2):289-294
A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them,
15 accessions presented 2n = 18; 27 accessions, 2n = 36; and 2 accessions, 2n = 45 chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In
the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities
were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low
frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number
and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce
interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions. 相似文献