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Polyphasic taxonomic analysis was carried out for Bacillus sp. strain C6, as the antagonist of phytopathogenic bacteria and micromycetes. The combination of cultural, morphological, physiological, and biochemical properties of the strain has enabled researchers to refer it to the Bacillus subtilis group. It has been shown that the fatty acids of the strain’s cell walls were predominantly represented by branched iso- and anteiso-C15:0 and C17:0 fatty acids (over 85%), which was typical for the Bacillus amyloliquefaciens species. The molecular genetic analysis carried out on the nucleotide sequence of the 16S rRNA gene, and the profiling of polymorphic nucleotides have enabled researchers to refer the strain in question to Bacillus amyloliquefaciens subsp. plantarum.

Aim To study the effect of antibiotic exometabolites of Bacillus amyloliquefaciens subsp. plantarum IMV B-7524 strain on the induction of defense responses in young plants of winter wheat. Methods Microbiological, biochemical, phytopathological, statistical. Results It was found that, when pre-watering winter wheat plants with salicylic acid, the cell-free culture supernatant and lipopeptide fraction of IMV B-7524 strain exometabolites during the further infection with phytopathogen Bipolaris sorokiniana, the damaged surface area of leaves decreased more than 10 times compared to the control. It was shown that in the roots and shoots of winter wheat plants L-phenylalanine ammonia-lyase (PAL) activity increased about 3 times in 2 hours after treatment. Conclusion Reduction of the damaged surface area of leaves by the action of fungal phytopathogen and change of PAL activity in plants indicate the induction of defense responses under the influence of antibiotic exometabolites of B. amyloliquefaciens subsp. plantarum IMV B-7524 strain.

To study the effect of antibiotic exometabolites of Bacillus amyloliquefaciens subsp. plantarum IMV B-7524 strain on the induction of defense responses in young plants of winter wheat.Microbiological, biochemical, phytopathological, statistical.It was found that, when pre-watering winter wheat plants with salicylic acid, the cell-free culture supernatant and lipopeptide fraction of IMV B-7524 strain exometabolites during the further infection with phytopathogen Bipolaris sorokiniana, the damaged surface area of leaves decreased more than 10 times compared to the control. It was shown that in the roots and shoots of winter wheat plants L-phenylalanine ammonia-lyase (PAL) activity increased about 3 times in 2 hours after treatment.Reduction of the damaged surface area of leaves by the action of fungal phytopathogen and change of PAL activity in plants indicate the induction of defense responses under the influence of antibiotic exometabolites of B. amyloliquefaciens subsp. plantarum IMV B-7524 strain.

Antagonistic activity 100 strains of Bacillus bacteria towards to museum and actual strains of phytopathogenic bacteria and fungy was defined. Relation between level of antagonistic activity to phytopathogenic bacteria and genus accessory of the last was shown. The medium level of antagonism to fungal phytopathogens at 30% of the studied strains of Bacillus bacteria was shown. 5 strains of Bacillus sp. with high and medium levels of antagonism to phytopathogens bacterial and fungy nature was selected and considered as perspective for creation of biological preparations for plant protection.

Aim. To research the antifungal activity and gene expression of lipopeptide antibiotics in strains of genus Bacillus. Methods. Deferred antagonism method, PCR, qRT-PCR, MALDI-TOF mass spectrometry. Results. It was revealed that Bacillus sp. strains C6 and Lg37s out of five tested strains had the highest antifungal activity. Based on the molecular genetic methods, it was shown that the expression of genes of lipopeptide antibiotics, related to the fengycin family, occurred in all these strains. At the same time, the gene expression of cyclolipopeptide iturin was found in the Bacillus sp. strains C6 and Lg37s. It was determined that Bacillus sp. C6 strain had the highest level of expression of the fengycin operon`s genes, whereas the lowest level was observed in Bacillus sp. C10 strain. By means of MALDI-TOF mass spectrometry, the presence of fengycins in the cell-free cultural fluid of Bacillus sp. C6 strain was detected. Conclusion. The direct correlation between the level of antifungal activity and the fengycin synthetases expression has not been disclosed. A higher level of antagonism detected for two Bacillus strains is more likely associated with the expression and subsequent synthesis of fengycin and iturin. Мета. Дослідити протигрибкову активність та експресію генів ліпопептідних антибіотиків у штамів бактерій роду Bacillus. Методи. Метод відстроченого антагонізму, PCR, qRT-PCR, MALDI-TOF мас-спектрометрія. Результати. З п'яти досліджених штамів найбільшу протигрибкову активністю показали штами Bacillus sp. С6 і Lg37s. Визначено, що у всіх штамів відбувається експресія генів ліпопептідних антибіотиків сімейства фенгіцінов. Для штамів Bacillus sp. С6 і Lg37s показана експресія гену синтезу ціклоліпопептіда ітуріна, найбільш активно експресуються гени фенгіцінового оперона у штаму Bacillus sp. С 6, найменш – у Bacillus sp. С 10. За допомогою MALDI-TOF масспектрометрії виявлено наявність фенгіцінов в безклітинній культуральній рідини штаму Bacillus sp. С6. Висновки. Прямої залежності між рівнем протигрибкової активності і експресією фенгіцінсінтетаз не виявлено. Більш високий рівень антагонізму, виявлений у двох штамів бацил, ймовірно, пов'язаний з експресією генів та подальшим синтезом фенгіціну та ітуріну. Цель. Исследовать противогрибковую активность и экспрессию генов липопептидных антибиотиков у штаммов бактерий рода Bacillus. Методы. Метод отсроченного антагонизма, PCR, qRT-PCR, MALDI-TOF масс-спектрометрия. Результаты. Из пяти исследованных штаммов наибольшей противогрибковой активностью обладают штаммы Bacillus sp. С6 и Lg37s. Показано, что у всех штаммов происходит экспрессия генов липопептидных антибиотиков семейства фенгицинов. Для штаммов Bacillus sp. С6 и Lg37s показана экспрессия гена циклолипопептида итурина, наиболее активно экспрессируются гены фенгицинового оперона у штамма Bacillus sp. С6, наименее – у Bacillus sp. С10. С помощью MALDI-TOF масс-спектрометрии обнаружено наличие фенгицинов в бесклеточной культуральной жидкости штамма Bacillus sp. С 6. Выводы. Прямой зависимости между уровнем противогрибковой активности и экспрессией фенгицинсинтетаз не установлено. Более высокий уровень антагонизма, обнаруженный у двух штаммов бацилл, вероятно, связан с экспрессией и дальнейшим синтезом фенгицина и итурина.