Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


Genomic rearrangements aff ect the resistance of biofi lms of soil bacteria Azospirillum brasilense to abiotic stress

The bacteria Azospirillum brasilense, used as biofertilizers, have a signifi cant positive eff ect on the growth and development of plants. The genome of the strain A. brasilense Sp7 is represented by a chromosome and numerous plasmids with molecular weight of 90, 115, and over 300 MDa. Genomic rearrangements that cause changes in the “plasmid profi le” can contribute to the formation of subpopulations or phenotypic variants in a bacterial population. There is little data on the role of such rearrangements in the adaptation of A.


Используемые в качестве биоудобрений бактерии Azospirillum brasilense оказывают существенное положительное влияние на рост и развитие растений. Геном типового штамма A. brasilense Sp7 представлен хромосомой и многочисленными плазмидами с молекулярной массой 90, 115 и более 300 МДа. Геномные перестройки, вызывающие изменения «плазмидного профиля», могут способствовать формированию в бактериальной популяции субпопуляций или фенотипических вариантов. Имеется мало данных о роли таких перестроек в адаптации A. brasilense к динамичным условиям окружающей среды.

Changes in the physicochemical and cultural properties of the bacteria Azospirillum baldaniorum Sp245 under the infl uence of some synthetic coumarins

Due to the small number of studies on the role of coumarins in associative symbiotic relationships, some aspects of the infl uence of synthetic coumarins on the physicochemical and cultural properties of Azospirillum baldaniorum Sp245 were studied for the fi rst time. To reveal the role of hydroxylation in position 7 of the fused aromatic ring – 1-(2-oxo-2H-chromen-3-yl)butan-1,3-dione, comparative studies of the eff ect of the original and hydroxylated coumarins on the culture of a model strain of azospirilla were carried out.

Analysis of Protease Effect on Biofilm Structure of Azospirillum Brasilense Strain Sp245 and Its Flagellation-Defective mmsB1 and fabG1 Mutants

Azospirillum bacteria are engaged in associative interactions with a wide range of plants. In this type of interaction, there formed no specialized structures like nodules, which are characteristic of the legume-Rhizobium symbiosis. The formation of biofilms by Azospirillum on the plant root surface can be important for the successful functioning of plant-microbe associations. Scarce data exist on the role of cell surface protein structures in the formation and stabilization of Azospirillum biofilms. It is known that as compared to A.