Effect of brain acid extract products in inbred mice on 3H-diazepam reception

The influence of brain acid extract products, isolated by high-performance liquid chromatography on H3-diazepam binding was investigated in synaptosomal membranes of C57BL/6 and BALB/c mice. Fractions with stimulatory and inhibitory activity were isolated. Quantitative and qualitative differences in the effects and structure of ACTH-immunoreactive peptide fractions under study were established.     

The substrate specificity of trypsin. The interrelationship between the structure and reactivity for quasi-substrates, derivatives of O-alkylmethylphosphonic acid and carboxylic acids

The kinetics of trypsin phosphorylation by thioesters of O-n-alkylmethylphosphonic acids, and reactivation of corresponding phosphoryl enzymes as well as kinetics of trypsin-catalyzed hydrolysis of p-nitrophenylcarboxylates have been studied. The rate constants for phosphorylation and dephosphorylation of trypsin depend on hydrophobicity of non-polar fragments in both substrate series in the same degree. On the other hand, the deacylation rate constants for a series of acyl trypsins do not change significantly while the apparent Michaelis constants change consistently with variations of non-polar acyl substituent. The study of substrate specificity of trypsin in terms of the transition state theory has allowed to elucidate the basis for low reactivity of trypsin towards the quasisubstrates.     

Through the Looking Glass of Biotechnology: D-Proteins as Objects of Patent Protection

Russian Journal of Bioorganic Chemistry - This article is devoted to the patenting of proteins, containing D-isoforms of amino acids, its potential problems and perspectives. Today, technologies...     

Tritium planigraphy comparative structural study of tobacco mosaic virus and its mutant with altered host specificity.

Spatial organization of wild-type (strain U1) tobacco mosaic virus (TMV) and of the temperature-sensitive TMV ts21-66 mutant was compared by tritium planigraphy. The ts21-66 mutant contains two substitutions in the coat protein (Ile21-->Thr and Asp66-->Gly) and, in contrast with U1, induces a hypersensitive response (formation of necroses) on the leaves of plants bearing a host resistance gene N' (for example Nicotiana sylvestris); TMV U1 induces systemic infection (mosaic) on the leaves of such plants. Tritium distribution along the coat protein (CP) polypeptide chain was determined after labelling of both isolated CP preparations and intact virions. In the case of the isolated low-order (3-4S) CP aggregates no reliable differences in tritium distribution between U1 and ts21-66 were found. But in labelling of the intact virions a significant difference between the wild-type and mutant CPs was observed: the N-terminal region of ts21-66 CP incorporated half the amount of tritium than the corresponding region of U1 CP. This means that in U1 virions the CP N-terminal segment is more exposed on the virion surface than in ts21-66 virions. The possibility of direct participation of the N-terminal tail of U1 CP subunits in the process of the N' hypersensitive response suppression is discussed.     

Conversion of Natural and Associated Petroleum Gases in Cold Electron-Beam Plasma

A device is developed to create cold nonequilibrium electron-beam plasma in a supersonic gas flow. The possibility of conversion of natural and associated petroleum gases into products with different chemical compositions by using this plasma is demonstrated. With the use of laboratory equipment, we find various products of oxidative and nonoxidative conversion. The proposed method is promising for industrial application.     

NO-inhibiting activity of radioprotectors

The effect of radioprotectors of different structure on the syntheses of nitric oxide induced by endotoxin in mice was studied. Using ESR-spectroscopy and spin trap techniques, it was shown that compounds of different chemical structure, such as aminothiols, isothiuronium derivatives, thiazolines, indolylalkylamines and others, suppressed the nitric oxide production in a whole body. The analysis of the relevant literature has confirmed the phenomenon described by the authors: radioprotectors show NO-inhibiting activity.