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Incubation of mixed human saliva with arginine, ornithine, and proline for 30 min to 2 h at 40 degrees C leads to an appreciable consumption of the above amino acids. The rate of utilization is 0.2 to 0.5 ncat/ml of saliva. The rate of urea loss is higher by an order of magnitude: up to 11 ncat/ml. Putrescin, urea (after incubation with arginine), and ammonium are identified as the products of these reactions. The biological significance of such reactions is believed to consist in neutralization of carbohydrate fermentation products. The detected consumption of amino acids and urea indicates that mixed human saliva contains urease, arginase, ornithine decarboxylase, and, probably, proline reductase. Since the origin of these enzymes is probably bacterial, changes in their activity in the saliva can be regarded as an indicator of dysbacteriosis and a diagnostically important parameter.

The method of exhaustive methylation with diasomethane was used as applied for actinoidines A and B and their glycosides for elucidation of the problem of connection between the carbohydrates and oxyaromatic fragments of the antibiotics followed by analysis of the acid hydrolyzates of the methoxy derivatives. It was found that the disaccarhide branch, i.e. 2-O-(L-acozaminyl)-D-glucose was connected in actinoidines A and B through the phenol group of the triaminotricarbonic fragment V, while the residue of D-mannose was connected through one of the phenol groups of the actinoidinic amino acid. The other two phenolic groups of the actinoidinic amino acid, as well as the phenolic groups of the N-end amino acids did not participate ion formation of the glycoside bonds. Actinosamine was probably connected through the alcohol group of the aglycone.

Five individual ninhydrin positive fractions were found in the blood serum of rats in the control group with the help of high voltage electrophoresis in combination with preparative high voltage electrophoresis and paper chromatography. An analogous analysis of the blood serum of the test animals treated with 50 mg/kg of chlortetracycline for 12 days revealed 1 new fraction in the weak basic region. After the use of chlortetracycline for 18 days 2 new fractions in the strong acid region, 1 new fraction at the level of the electrophoretic mobility of asparaginic acid and 2 fractions in the region between neutral and basic amino acids were found. Analysis of the above fractions showed that the blood sera of the control and test rats contained in addition to the free amino acids peptides consisting of 3 to 9 amino acid residues. Some peptides isolated from the sera of the test animals contained amino acids, such as ornithine and citrulline which are not usually contained in proteins.

The authors accomplished a study of the concentration of free aminoacids in the blood and urine of patients with torsion dystonia by means of a high voltage electrophoresis with a subsequent ascending chromatography. A division of such patients into 2 clinical forms is reflected in the found concentration of free aminoacids in the blood and urine. In patients with the rigid form along with generalized hyperacidemia there are also significant changes in the concentration of aminoacids of the aromatic line. In the group of patients with the hyperkinetic form the most significant changes were seen for valine, methionine, serine, alanine and cystine, while as the spectrum of aminoacids of the aromatic line is practically unchanged. The found changes in the spectrum of free aminoacids are most likely connected with disorders of catecholamine metabolism in torsion dystonia.

A mixture of pH 3.5-soluble trypsin peptides of inclusion bodies proteins of moth nuclear polyedrosis virus was fractionated by means of ionic exchange chromatography on Dowex 50X2 and purified by paper electrophoresis-chromatography. 32 peptides are isolated, their amino acid composition being studied.

Possible causes of disturbances of the amino acid pool of the blood serum and the tissue, as well as the presence of an association between these shifts and the changes in the ultrastructure of the striated columnar epithelium of the small intestine were studied. Investigations were conducted in 138 patients suffereing from salmonellosis and in 120 albino rats experimentally-infected with S. typhimurium culture. Free amino acids of the blood serum and the tissue were determined by paper chromatography and on the automatic amino acid analyzer; ultrastructure of the small intestinal mucosa was studied by electron microscopy. The height of salmonella infection was attended by dysproportional changes in the amino acid pool of the tissue and the blood caused by disturbance of absorption and intracellular transformation of amino acids. Ultrastructural changes in the microvilli of the absorbing cells of the small intestine underlied absorption disturbances: at the height of salmonella infection some of the microvilli of the striated columnar small intestine proved to show poor contours; reduction of mitochondrial cristae was observed in almost all the mitochondria.

The growth, assimilation of organic nitrogen compounds, and production and distribution of free amino acids were studied during the growth of Cunninghamella elegans (--) 1204 on the defined medium 12 containing glucose and dodecane and without an additional carbon source (control). The culture utilized all leucine, glycine, and asparagine after three days of the growth, irrespective of the source of carbon in the medium. Glutamic acid was assimilated only in the presence of glucose. Some 15 free amino acids and 2 amides were detected in the cells, and also some correlations in the composition of the pool in the presence of different sources of carbon in the medium. The substitution of dodecane for glucose decelerates metabolism of free intracellular amino acids and stimulates their accumulation in the cells, especially if there is a deficiency of carbon sources: the overall content of amino acids and amides on the medium with glucose is from 2.2 to 4.1 mg/g; with dodecane, from 9.8 to 16.5 mg/g; in the control, from 16.4 to 25.8 mg/g.

The paper presents new data concerning the mechanism of microbiological dissolution of gold. The sign of charges on gold-protein complexes was determined by paper electrophoresis. Anion complexes were found to prevail. Free amino groups participate in formation of complexes between gold and amino acids in alkaline medium, and functional groups of amino acid residues in polypeptide groups are involved in formation of complexes with proteins. Formation of complexes between gold and these compounds seems to be due to the Au--N bond.