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41.
The spatial structure of methylamide N-acetyl-L-argine was studied taking into account the non-valent and electrostati interactions, the torsion energy, and the distorsion of valency angles. Calculation of the favourable conformations of the molecule was carried out with the use of all the combinations of angles phi, psi, chi1 divided by chi4 as an intital approximation. These correspond to the low energy forms of the main chain and to the minima of the torsion potentials of the side chain. Conformational possibilities of arginine and lysine were compared. The calculated stable conformation of N-acetyl-L-arginine-methylamide are compared with the geometry of arginine residues in the proteins with known structure. 相似文献
42.
A set of conformations was shown to be characteristic of the free-state spatial structure of substrate-like inhibitor JG-365 for aspartic protease from HIV-1. Among them, the lowest-energy conformations have a folded form of the peptide backbone. The inhibitor has a noncleavable hydroxyethylamine group with an additional chiral center in its structure. Our calculations showed that only the S-isomer of the inhibitor displays conformational characteristics that practically coincide with those of the native substrate for HIV-1 protease. One of the calculated conformations with a completely extended main chain and a relative energy of 9.5 kcal/mol very closely mimics the experimentally observed structure of the inhibitor in the enzyme-inhibitor complex. The realization of this structure is unlikely for a free inhibitor, because it has only a small number of interresidual noncovalent interactions in the extended conformation; these are presumably compensated for by intermolecular interactions at the active site of the enzyme. 相似文献
43.
The main patterns of the functioning of the photosynthetic system of the French bean were established on the basis of comparative tests of eight cultivars and varieties. Some agrotechnical methods were developed which enhance the highest efficiency of the plant's photosynthetic activity. The data obtained are essential for the introduction of promising varieties of the bean cultures in the nonchernozem zone of Russia. 相似文献
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V A Gabassov E G Popov I Iu Gavrilov E Ia Pozin R A Markosian 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(10):437-440
A new approach to the investigation of the kinetics of platelet aggregation is described. The method is based on the analysis of light transmission fluctuations produced on the changes in the number of platelets in optical channel. The relative dispersion of the fluctuations of transmitted light intensity was used as a parameter to estimate the degree of platelet aggregation. Application of this method for the analysis of platelet aggregation permits to get new information about this process. 相似文献
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Electron-microscopic and electron-cytochemical method were used to indicate the capability of Pseudomonas mallei (str. N 10230) to produce extracellular slime during the agent growth on the meat-peptone agar. In case of guinea pigs infection the agent forms a capsule that defends the pathogen from phagocytosis. 相似文献
49.
Popov A. Yu. Tretinnikov P. V. Gusakov E. Z. Simonchik L. V. 《Plasma Physics Reports》2020,46(1):35-40
Plasma Physics Reports - The expression is obtained for the high-frequency quadratic susceptibility of the strongly inhomogeneous magnetoactive plasma, which describes the nonlinear coupling... 相似文献
50.
Russian Journal of Plant Physiology - Changes in the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) for the plants Nicotiana tabacum L. and Secale cereale L.... 相似文献