[Hydrolysis of a Staphylococcus aureus cell wall peptidoglycan by 209 P lysoamidase]. / Gidroliz peptidoglikana kletochnykh stenok Staphylococcus aureus 209 P lizoamidazoi.

Hydrolysis of Staphylococcus aureus 209 P cell wall peptidoglycan was accompanied by the liberation of 1.3 mol of C-terminal and 1.2 mol of N-terminal glycine per mole of Glu as well as of 0.5 mol of N-terminal and 0.3 mol of C-terminal alanine. Gel chromatography on Sephadex G-25, ion-exchange chromatography on QAE-Sephadex A-50 and paper electrophoresis of S. aureus peptidoglycan hydrolysates gave seven homogeneous fractions; these fractions were structurally defined. Lysoamidase hydrolyzed bonds Mur-Ala, Gly-Gly and Mur-GlcN in the peptidoglycan molecule. Hydrolysis of glycan chains was accompanied by the formation of large fragments, (GlcN-Mur)9 and (GlcN-Mur)28. The lytic effect of lysoamidase on S. aureus peptidoglycan is coupled with bacteriolytic enzymes of lysoamidase: acetmuramyl amidase, glycyl--glycine endopeptidase and acetyl--muramidase.

[Effect of the exogenous tryptophan on biosynthesis of ergot alkaloids in Penicillium sizovae]. / Vliianie ékzogennogo triptofana na biosintez érgoalkaloidov u Penicillium sizovae.

Various concentrations of exogenous L and D-tryptophan as well as of their analogue D,L-6-methyltryptophan were added to the growth medium of Penicillium sizovae during its inoculation and after the active growth of the fungus was over. The authors studied the effect of these compounds on the accumulation of exocellular alkaloids and biomass as well as on the synthesis of proteins, the content of free tryptophan in the cells, and the activity of tryptophan synthetase. As was shown in experiments using labeled tryptophan, this amino acid is a direct precursor of alkaloids in the culture.

[Effect of the growth rate on the biomass composition of Candida valida]. / Vliianie skorosti rosta na sostav biomassy u Candida valida.

The effect of growth rate on the biomass composition was studied with a thermotolerant strain of the yeast Candida valida grown in the chemostat at limitation of the growth by ethanol under the conditions of various temperature regimes. The temperature and the growth rate hardly influenced the content of protein and its amino acid composition. An increase in the specific growth rate of the cells caused a rise in the pool of free intracellular amino acids, in particular, glutamic acid. The degree of lipid unsaturation increased with a rise in the growth rate of the yeast as a result of intensification of oleic acid oxidative dehydration. As it had been shown earlier, the content of nucleic acids increased with a rise in the specific growth rate of the yeast.

[Amino acid composition and proton capacity of pea chloroplast thylakoid membranes]. / Aminokislotnyi sostav i protonnaia emkost' tilakoidnykh membran khloroplastov gorokha.

The amino acid composition and pH dependence of proton capacity of pea chloroplast thylakoid membranes have been studied. The thylakoid membranes possess a high content of amino acids, whose functional groups can either bind or split off protons depending on pH of the reaction mixture. The number of amino acids with proton-accepting functional groups per mg of chlorophyll significantly exceeds the proton capacity of the native membranes. It is concluded that the buffer capacity of thylakoid membranes is predetermined by the proton-accepting groups of protein components which are largely blocked within the native structure of the membranes. The protein/chlorophyll weight ratio for pea chloroplast thylakoid membranes is 3.22 +/- 0.05.

[Comparative study of the growth parameters of methanotropic bacteria]. / Sravnitel'noe izuchenie parametrov rosta metanotrofnykh bakterii

Growth parameters and their interrelationship were determined for two mixed and seven pure cultures of methanotrophic bacteria. The specific growth rate, the rate of methane assimilation, and the economic coefficient changed significantly in the course of cultivation of the methanotrophic cultures in the periodic regime, the changes being of the extremem character. Therefore, mean values of the growth parameters of these cultures determined under identical conditions were compared. These parameters were found to be dependent on the taxonomy of the cultures and on the conditions of their growth. No considerable differences had been found in the growth parameters between mixed and pure methanotrophous cultures. Portions of the carbon of methane expended for synthesis of the biomass, carbon dioxide, and exometabolites was different among methanotrophic cultures belonging to different genera.