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The purpose of this work is to purify and identify compounds from Bacillus ginsengihumi M2.11 that have fungicidal activity. Isolation of active metabolites was carried out by sample preparation, concentration, and chromatography. Substances were identified using a Maxsis impact mass spectrometer (Bruker). The results obtained were processed in the DataAnalysis Version 4.1 program. We searched library databases presented on the servers http://www.massbank.jp; http://www.chemspider.com. The most likely substance with fungicidal activity is a compound with m/z 1079, which is a lipopeptide. In this work, the fungicidal compound produced by the strain B. ginsengihumi M2.11 is a biosurfactant – disodium surfactin, with molecular formula C53H91N7Na2O13. Thus, the biocontrol function of the B. ginsengihumi M2.11 strain is largely determined by the secretion of surfactants – biosurfactants. Studying the mechanisms and modes of action of the active compound will allow full use in agriculture to protect plants from phytopogens, increase the quality and quantity of yield.

Phytic acid is the main storage form of organic phosphorus. Due to its structural features, phosphorus in phytate is inaccessible for assimilation by animals. Moreover, remaining inaccessible reservoir of phosphorus for animal nutrition, phytic acid is capable of forming insoluble complex salts, which lead to soil and water pollution. Мicrobial enzymes - phytases, capable of decomposing phytic acid to organic phosphorus are being used as feed additives in animal nutrition to solve this problem. Thus, search and development of technologies for the production of enzymes on an industrial scale are the most urgent. Methylotrophic yeast P. pastoris are widely used in biotechnology, as an efficient system for the recombinant proteins expression. They have many advantages, including rapid growth on inexpensive media, a wide range of molecular tools for genetic manipulation in optimizing production processes, they are safe for humans and animals, carry-out many post-translational modifications and produce recombinant proteins intracellularly or extracellularly within a short period of time. It was found that the recombinant P. pastoris strains pPINK-LC-α-MF -phyC, pPINK-HC-α-amyl -phyC, pPINK-LC-α-amyl -phyC, pPINK-HC-α-MF -phyC are able to produce and to secrete B. ginsengihumi bacterial phytase M 2.11 phyC. The maximum activity was observed in the pPINK-LC-α-MF strain – 2.6 (U / mg). Recombinant B. ginsengihumi M 2.11 phytases exhibited high activity in a wide pH range from 2.5 to 9.0. The MF-phyC-HC construction is pH stable. The temperature optimum of all recombinant phytases corresponds to 37 ° C; recombinant phytases retain their activity in the range from -80 to 90C.

Phytate-hydrolyzing bacteria Pantoea sp. 3.1, 3.2, 3.5.2, 3.6.1 and Bacillus ginsengihumi M2.11 were previously isolated from the soil samples of the Republic of Tatarstan. The effect of cultivation conditions on the growth dynamics as well as antimicrobial activity was determined. All four Pantoea strains showed optimum growth at 26 ºC and 28 ºC and pH 6.0-7.0. The optimum conditions for the growth of B. ginsengihumi M2.11 strain was determined to be 26 ºC, 28 ºC and 37 ºC and alkaline pH 7 and 8. Salt concentration in the range of 0 to 1000 mM did not significantly affect the growth of the strains. Antagonistic activity of Pantoea sp. 3.5.2 was studied against phytopathogenic micromycetes, identified as Alternaria alternata and Bipolaris sorokiniana. In the presence of bacterial isolate growth of A. alternata was inhibited by 57% and growth of B. sorokiniana – by 85%. Minor growth inhibition by Pantoea sp. 3.5.2 of gram-negative bacteria from Enterobacteriaceae family was observed. The presence of fungicidal activity in the Pantoea strain together with its ability to hydrolyze soil phytates and overcome abiotic stress factors in soil can possibly serve as the basis for the new fungicide of microbial origin.