Composition and structure of the antibiotic polypeptide 308-I from Actinomadura recticatena

Antibiotic 308-I isolated from Actinomadura recticatena and the products of its degradation were studied with the methods of electron impact mass spectrometry, chemical ionization with ammonia, field desorption and ion extraction from solution under atmospheric pressure. It was shown that by its composition and structure antibiotic 308-I was identical to antibiotic BBM-928 A.     

A new class of cardiotonic steroids]

A series of 23-oxosteroid derivatives have been synthesized and tested for their inhibiting Na+, K(+)-dependent ATPase from rat brain in the 1 x 10(-6)-1 x 10(-4) M concentrations. Natural 23-oxogenins from sea star Asterias amurensis and synthetic monoesters showed the inhibiting activity upto 50-55%. These compounds caused heart contraction in frogs at the level of the known cardiotonic strophanthin G, and inotropic activity on isolated heart of mollusk Spisula sachalinensis.     

Microbiological dehydrogenation of polyfunctional Δ5-3β-acetoxy steroids by Corynebacterium mediolanum strain B-964

Summary A high-yield microbiological transformation of polyfunctional ⁵-3-acetoxy steroids, containing an additional ring E, by Corynebacterium mediolanum strain B-964 was carried out, resulting in the corresponding ⁴-3-ketones. It was shown that the type of transformation and the yield of the reaction depend on the degree of saturation of the ring E and on the position of the oxygen-containing substituents in it.     

Isolated water in desiccated microorganisms

The presence of isolated mobile water in dehydrated eukaryotic microorganisms established earlier by NMR has been confirmed by direct chemical registration of this water in the yeast Cryptococcus albidus. This water constitutes several per cent of the dry biomass weight. Apparently, its preservation should be attributed to changes in the permeability of intracellular membranes upon dehydration. The water is released by the cells when they are heated to 150--200 degrees C and the cellular structures containing water are destroyed.     

Activity of Ion Transporters and Salt Tolerance in Barley

The authors attempted to relate the cultivar-specific salt tolerance in barley (Hordeum distichum L.) to the efficiency of ion transporters in the plasmalemma and tonoplast. The study involved plasmalemma and tonoplast membrane vesicles isolated from roots and leaves of the 7-day-old barley seedlings exposed to elevated NaCl concentrations. Two barley cultivars were employed: salt-tolerant cv. Elo and salt-susceptible cv. Belogorskii. The vesicles were used to measure the transport activity of plasmalemma and tonoplast proton pumps and the cation/anion exchange. The data obtained in the experiments demonstrated that the changes in the activity of ion transporters under salt stress conditions correlated with the barley cultivar-specific tolerance to elevated NaCl concentrations.     

Immunoenzyme analysis of ovarian metastatic antigen-8]

Immunoenzymatic method for the determination of new ovarian-metastatic antigen-8 in human blood serum was worked out. OMA-8 level was studied in blood serum of 40 healthy women, 40 healthy men, 16 neonates, 33 pregnant women, 103 patients with genital tumours. It was found out that OMA-8 level in blood serum of healthy women changed between 2 to 15.4 micrograms/l, in men between 5-17.0 microgramS/l. OMA-8 concentration higher than 15.4 micrograms/ was considered elevated. The elevated OMA-8 level was marked in neonates (100%) and in pregnant (39.3%). High level was discovered in the amniotic fluid.     

Fusicoccin-Like Ligands in Higher Plants

Fusicoccin-like ligands in higher plants were sought by combining high performance liquid chromatography with radioreceptor analysis and radioimmunoassay. Such substances were found in genetically transformed cultured roots of horseradish, alteus and lupine as well as in native horseradish, cucumber, horse chestnut, and maize plants. In root crops such as carrot and sugar beet or in potato tubers, only traces of fusicoccin-like ligands were detected. Fusicoccin A was detected in genetically transformed cultured roots of horseradish by gas chromatography/mass spectrometry. Received October 15, 1996; accepted February 14, 1997     

Isolation and structure of the active component of the antitumor agent blastolysin

Active principle of blastolysin, comprising ca. 40% of the total weight of Lactobacillus bulgaricus cell wall preparation, has been isolated and structurally studied by chemical and spectral methods. The substance a glycopeptide with Mr aa. 10,000, consists of two tetrasaccharide moieties connected by oligopeptide bridges; glycerophosphate, glucose, and galactose moieties are also attached to N-acetylmuramyl residue of the peptidoglucan core. Tetrasaccharide-containing muramylpeptides were shown to be responsible for the antitumour activity.