[Characteristics of proteins synthesized by hydrogen-oxidizing microorganisms].

The study was conducted to determine the biological value of proteins synthesized by hydrogen-oxidizing microorganisms--the hydrogen bacteria Alcaligenes eutrophus Z1 and Ralstonia eutropha B5786 and the CO-resistant strain of carboxydobacterium Seliberia carboxydohydrogena Z1062. Based on a number of significant parameters characterizing the biological value of a product, the proteins of hydrogen-oxidizing microorganisms have been found to occupy an intermediate position between traditional animal and plant proteins. The high total protein in biomass of these microorganisms, their complete amino acid content, and availability to proteolytic enzymes allow for us to consider these microorganisms as potential protein producers.

[Biochemical quality assessment of broiler production using a hydrogen bacteria biomass in the diet]. / Biokhimicheskaia otsenka kachestva produktsii broilerov pri ispol'zovanii v ratsione biomassy vodorodnykh bakterii.

The authors studied the biochemical composition of the meat of broilers, eggs, liver and muscles of laying hens of 3 generations on a 5, 10, 25, 50 and 100% (broilers), 10 and 20% (laying hens) replacement of the animal protein quota in the diet by protein obtained from the hydrogen bacteria Alcaligenes eutrophus L-1. No deterioration of the quality of the produce was found from the standpoint of the main biochemical parameters.

[Nutritional value of the proteins of carboxydobacteria]. / Issledovanie pishchevoi tsennosti belkov karboksidobakterii.

The biological value of proteins from 3 carboxidobacterial strains was assessed on the basis of the protein amino acid content, consumption by the test-organism T. pyriformis and protein susceptibility to proteolytic enzymes in vitro. Carboxidobacterial proteins are characterized by a full-value amino acid composition and contain large amounts of all indispensable amino acids. This indicates that on the whole these proteins are quality ones. Experiments with the test-organisms have shown, however, that the relative biological value of the protein samples significantly yields to casein. The total digestibility of carboxidobacterial proteins by pepsin and trypsin in vitro is close to that of wheat vegetable proteins and lower as compared with that of casein. Carboxidobacterial proteins may be thus attributed to a protein group being an intermediate one between casein and wheat vegetable proteins.

[Characteristics of the proteins of unicellular organisms as potential components of ecological life-support systems]. / Kharakteristika belkov nekotorykh odnokletochnykh organizmov kak potentsial'nykh komponentov ékologicheskikh sistem zhizneobespecheniia.

A comparative characterization of the biological value of proteins from green and blue-green algae, bacteria, and microbial coenosis of straw mineralizing active sludge is given with respect to the fractional composition of total protein, its amino acid composition, and affinity for proteolytic enzymes in vitro. The above microorganisms have an adequate amino acid composition, a high content of essential amino acids, and differ in their content of readily soluble proteins. The presence of protein complexes with other cellular components, for instance lipids and carbohydrates, seems to be responsible for a poor digestibility of these proteins.

[Effects of the nitrogen nutrition conditions on the growth and protein synthesis of carboxydobacteria]. / Vliianie uslovii azotnogo pitaniia na rost i sintez belkov u karboksidobakterii.

The rate of growth of bacterial strains oxidizing carbon monoxide (Pseudomonas gazotropha Z-1156, Comamonas compransoris Z-1155, and Seliberia carboxydohydrogena Z--1062) was studied as a function of the concentration of NH4Cl in the medium. The bacteria could grow on media containing various nitrogen sources (NH4Cl, KNO3, CO(NH2)2). Changes in the amino acid content and biochemical composition of the biomass were studied during growth of the bacteria on these media. The biological value of proteins of the bacteria was estimated.

[Comparative characteristics of the amino acid composition of the protein fractions of the hydrogen bacteria Hydrogenomonas eutropha in meat and wheat]. / Sravnitel'naia kharakteristika aminokislotnogo sostava belkovykh fraktsii vodorodnykh bakterii Hydrogenomonas eutropa, miasi i pshenitsy

An attempt was made to compare the biological value of the biological mass of the hydrogen bacteria Tydrogenomas eutropha, of meat and wheat on the ground of the fractional and amino acids composition of their proteins. Substantial differences in the distribution of proteins and amino acids in all of the three objects examined were revealed. It is shown that more than one half of the entire protein contained in the biological mass of the hydrogen bacteria is made up of poorly soluble structural proteins difficultly amenable to the action of digestive enzymes. It is this fraction where the bulk of essential amino acids is concentrated. The data obtained imply that the biological value of the biological mass of hydrogen bacteria is higher than in wheat, but lower than in meat.

[Dynamics of the amino acid composition of the medium during cultivation of isolated liver and kidney by the controlled perfusion method]. / Dinamika aminokislotnogo sostava sredy pri kul'tivirovanii izolirovannykh pecheni i pochki metodom upravliaemoi perfuzii

The dynamics of the medium amino acid composition was studied during a 6-hour perfusion of dog kidney and liver by a mixture of autogenic plasma and medium 199 (a ratio of 2 : 3). In comparison to the initial level the amount of histidine during 6-hour cultivation of the kidney was found to increase 2.2 times, that of glutamic acid--1.7 times, and of alanine and lysine--1.6 times. At the same time the amount of arginine, serine and asparagic acid became 3.3 times and of glutamine and threonine--2.5 times lower. With the liver perfusion the level of glutaminic acid became 2.9 times, of alanine--2.3 times, of cystine--2 times and of glycine--1.5 times higher. With the liver perfusion the level of arginine decreased so rapidly that none was found in the medium after a 2-hour perfusion. The described method of amino acid analysis during the cultivation of the organs could serve as means for elaborating and correcting the culture media.

[Dynamics of the amino acid composition of the medium during cultivation of isolated organs by the directed perfusion method]. / Dinamika aminokislotnogo sostava sredy pri kul'tivirovanii izolirovannykh organov metodom upravliaemoi perfuzii

The dynamics of the amino acid composition of the medium under conditions of adequate perfusion of the isolated organs of a dog (sternum, kidney and liver) was studied. It was found that after a 6-hour perfusion of the complex of organs the amount in the perfusion medium of such amino acids as histidine, lysine, alanine, considerably increased, whereas the amount of arginine, serine, aspartic acid, threonine with glutamine, isoleucine, proline, leucine and valine decreased as compared with their initial concentration. The dynamics of the amino acid medium composition during a 4-hour perfusion was studied in experiments with the isolated sternum. The concentration of alanine, lysine and histidine increased in the medium. At the same time there was seen a decrease in the concentration of serine, aspartic acid, isoleucine, tyrosine and phenyl-alanine.