Effect of culture parameters on tobramycin biosynthesis

The effect of temperature, aeration and active acidity of the medium on biosynthesis of tobramycin was studied. The optimal temperature conditions (37 degrees C) were developed. It was shown that biosynthesis of tobramycin depended on the aeration conditions, especially at the beginning of the fermentation process. The initial pH 4.9-6.35 and 6.35-7.1 were found to be optimal for the growth of the tobramycin-producing organism and biosynthesis of the antibiotic, respectively.     

Distribution of Saprophytic Bacteria in the Atomic Submarine Accident Zone in Chazhma Bay, Sea of Japan

The numerical and taxonomic composition of saprophytic bacteria was studied in the atomic submarine accident zone in Chazhma Bay. With increasing depth in the epicenter of the accident zone, the mean of the ratio of bacterial taxa in the resistance series tends toward a constant. The numerical structure of the pelagic saprophytic bacterial assemblage becomes ordered as the bottom is approached. Analysis of radioactive suspended matter allowed us to obtain model distribution of numbers of all saprophytes and each taxon from the different environmental sources (sediment surface and upper layers of the sea).Original Russian Text Copyright © 2005 by Biologiya Morya, Ivanova, Gorshkova, Mikhailov, Sergeev, Gladkikh, Goryachev, Dudarev, Botsul, Mozherovsky, Slinko, Kiselev.