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The effect of the new drug "cerebral" and its fractions 1-3 on the model of bilateral hemorrhagic stroke in white rats was studied with reference to the action of cebrolysin and cerebrolysate-M. With respect to the general functional state, behavioral activity restoration, and morphological data, the most pronounced antistroke action was observed for the cerebral-1 fraction. This fraction was further separated into three subfractions. The most promising test results were obtained for the 1.2 subfraction, which was selected for the further investigation.

The results of experimental and theoretical studies on the combined action of weak electrical as well as constant and variable low-frequently magnetic fields on physicochemical and biological systems are generalised. It is shown that weak magnetic fields with parameters close to characteristics of the geomagnetic field exert selective effects, initiating the processes of chemical reactivity and ion conductivity in aqueous solutions of organic molecules.

A comparison of the three known methods made it possible to work out methods of complex extraction of deutero amino acids, deutero sugars and deutero vitamins from algae Chlorella sp. K., grown autotrophically in heavy water. An analysis of the isotopic composition of deutero amino acids by PMR indicates that treatment with HCl introduces 1H into side chains of some amino acids by chemical exchange (C2, 6H of tyrosine, C2H of histidine, rho-H of phenylalanin, beta-CH2-aspartate and gamma-CH2-glutamate. These exchanges made the amino acids convenient to be used as the substrates for the growth of heterotrophic selective deuterated organisms as a source of selective deuterated proteins.

The paper describes a method for separation of dansylated amino acids by polyacrylamide gel electrophoresis. The methods allows a simultaneous analysis of 20-30 samples. The sensitivity of the method is 1 x 10(-9)-1 x 10(-10) M amino acid. The method permits separation of all amino acids formed during acid hydrolysis of proteins except for two pairs: Ile, Phe and Val, Asp.

An unusual ninhydrin-positive compound has been isolated from feces of accidentally contaminated Sprague-Dawley autbred rats and identified by mass spectrometry and 1H-NMR spectroscopy techniques as 5-aminovaleric acid. The described procedure of isolation, purification and structure determination can be recommended as a general method of identification of unusual ninhydrin-positive compounds in complex mixtures of biological origin. The 5-aminovaleric acid was found to be produced by an anaerobic bacterium Clostridium bifermentans. It is shown that not all Clostridium spp. excrete his amino acid and that the majority of microorganisms, normally inhabiting intestine of rats, simians and man, do not possess this ability. On the basis of data obtained, the test for 5-aminovaleric acid is proposed to be included into the taxonomy of bacteria.

Yeast autolysis and hydrolysate composition were studied with respect to the autolysis of baker's pressed yeast. A method of isolating a mixture of amino acids and lower peptides from autolysates was developed, using ion-exchange resins. The above compounds reached maximum accumulation by the 15-20th hour of autolysis. A mixture of amino acids applicable to nutrition, including dietotherapy, was prepared.

A procedure for preparation of samples is described for emission-spectroscopic estimation of 15N in ammonia, glutamic aspartic acids, leucine and glycine using 15N-analyzer NOI-5. The assay involved separation of ammonia and amino acids by means of ion exchange chromatography, degradation of amino acids to ammonia its isolation by microdiffusion from buffers and subsequent reduction of ammonia to nitrogen. Amount of nitrogen in the samples was about 20 mg. The procedure enabled to estimate the content of 15N in ammonia and amino acids of physiological fluids.

Methods for obtaining protein hydrolysates with certain given properties are considered. It is shown that, besides food proteins, various yeast proteins can be used. Advantages and disadvantages of different types of hydrolysis, hydrolysis conditions, methods of hydrolysate purification and prevention of labile amino acid destruction are described.

A comparative amino acid analysis of botulinum neurotoxin type A and its subunits has been carried out. The heavy and light chains of neurotoxin have the same ratios of polar and non-polar amino acids (1.3:1), the amount of tryptophan residues in the heavy chain is 4 times as much as that in the light chain, and the number of SH-groups exceeds that in the light chains 2-fold. In neurotoxin, two N-terminal amino acid residues--alanine and leucine--were identified. Alanine was found to be the N-terminus of the heavy chain. The fluorescence spectra of neurotoxin subunits indicate differences in the conformational state of the polypeptide chains. The antigenic non-identity of botulinum neurotoxin A subunits suggests the presence in the neurotoxin molecule of at least two antigenic determinants, corresponding to the heavy and light chains.

A preparative method of isolation of the histone kinase regulatory subunit has been developed. The total number of cysteine residues in the enzyme (13 residues) and in each of its subunits (3 residues in the catalytic subunit and 10 residues in the regulatory one), has been determined. Two disulfide bridges have been found in the regulatory subunits. The relative availability of the sulfhydryl groups with respect to different modifying agents has been studied. It has been demonstrated that SH-groups blocking does not change essentially the enzyme activity.

The equilibrium distribution of acetyl-D-phenylglycine prepared with stereospecific hydrolysis of acetyl-D,L-phenylglycine (Ac-D,L-PhG) was studied in a two-phase system of benzyl alcohol-1N HCl solution. It was found that the distribution coefficient of Ac-D-PhG did not practically depend on its concentration in the aqueous phase. This means that Ac-D-PhG does not form associates in the organic phase. The studies provided development of an extraction polarimetric method for quantitative determination of Ac-D-PhG. The method implies extraction of Ac-D-PhG with benzyl alcohol from a strong acid medium (1N HCl solution), polarimetric determination of the equilibrium concentration of Ac-D-PhG in the organic phase and subsequent calculation of the initial concentration of Ac-D-PhG in the aqueous phase with regard to its distribution coefficient.

The sequence of the amino acid residues in the peptide chain of aglycone was shown on the basis of the data concerning the splitting of actinoidin aglycon and the products of its partial acid hydrolysis by various methods. It was found that the free COOH-group of actinoidin belonged to he glycine residue of the dioxyphenyl nucleus of actinoidinic amino acid. The site of the actinosamine attachment to aglycon was determined. The final structure of actinoidins A and B is suggested.

Retintion of some amino acids and peptides by standard ultrafiltration membranes "Vladipore" was studied. Membranes UAM-30M and UAM-50M may be used for concentration and desalting of peptides containing not less than 3-4 amino acid residues. An increase in NaCl concentration in the samples led to a decrease in the peptide retention coefficient. The ultrafiltration membranes were used for isolation of small peptides from blood, urine and extracts of normal skin, after thermal trauma and irradiation of the tissue.

The isolation of iodorganic compounds from the Black Sea red alga Phyllophora nervosa and its by-products obtained from industrial treatment was investigated. The algal biomass was pressed to remove alkali, subjected to 5-10 min treatment with 11-12% sodium hydrate, and drying at 125-130 degrees C and washed to yield 95% iodine and over 80% proteins. Iodine was found to be bound with protein of Phyllophora. Properties of the isolated iodine-peptide fractions were studied.

Various methods for quantitative description of amino acid sorption from solutions for parenteral nutrition on activated charcoal were studied under dynamic and static conditions. With the use of the well-known Freindlich and Langmuir absorption isotherms it was shown to be possible to describe in a simplified way the complex multicomponent process of sorption of the amino acids and to estimate their loss at the filtration stage.