CHARACTERISTICS OF ACTINOBACTERIA FROM MYTILUS GALLOPROVINCIALIS OF ODESSA GULF OF THE BLACK SEA

Today both academic and commercial interests in marine actinobacteria are growing. As they live in a unique environment that promotes the synthesis of new biologically active metabolites. The aim of the work is isolation, primary identification and study of morphological, cultural, physiological and biochemical properties of actinobacteria, separate from mussels (Mytilus galloprovincialis) of the Odessa Bay of the Black Sea. Methods. Samples of mussels collected in the coastal zone of Odessa Bay were used as material for the isolation of actinobacteria. Isolation of actinobacteria and the study of their morphological, cultural, physiological and biochemical properties was carried out by traditional microbiological methods. The fatty acid composition was determined on an Agilent 7890 semi-ionization gas chromatograph (Agilent Technologies, USA) to identify test strains using the Sherlock Microbial Identification System library. Results. From samples of mussels collected in 2020 in the area of the Hydrobiological Station of Odessa National I.I. Mechnikov University were isolated 14 strains of actinobacteria. They were identified by fatty acid analysis to Streptomyces genus. Strains of Streptomyces sp. Myt2, Myt6 and Myt7ch synthesized melanoid pigments. Strains of actinobacteria are well absorbed by most of the studied sources of carbon, except strains of Streptomyces sp. Myt12a, Myt12b. Almost half of the strains have oxidase activity and coagulate milk. Conclusions. As a result of microbiological studies for the first time were characterized morphological, cultural and physiological and biochemical properties and determined taxonomic composition by fatty acid spectra for actinobacteria isolated from the mussels of the Odessa Bay of the Black Sea.

ISOLATION OF BACTERIA FROM THE SITES OF FEED AND NESTING ACTIVITY OF LARUS DOMINICANUS (GALINDEZISLAND, THE MARITIMEANTARCTIC) AND THEIR CHARACTERISTICS

The aim of the study was to investigate the number of different groups of microorganisms in soil samples from sites of feed and nesting activity of Larus dominicanus (Galindez Island, the maritime Antarctic) and to characterize the physiological and biochemical properties of isolated microorganisms. Methods. In the work standard microbiological and biochemical research methods were used (cultural, microscopy methods, determination of enzymatic activity). Genomic DNA was isolated by soft lysis. The 16 S rRNA gene was amplified using universal primers 27F and 1492R. Identification of isolates was performed based on the determination of the 16 S rRNA gene sequence, physiological and biochemical properties. Results. The number of microorganisms of different groups in soil samples from sites of food and nesting activity of Larus dominicanus (Galindez Island, the maritime Antarctic) was established. 74 isolates of bacteria were isolated. Isolate 2U-K-37, that was isolated from upper layer of soil, and isolate 2B-K-54, that was isolated from a depth of 2–5 cm, were characterized by amylase, lipase, phospholipase, protease activities, the ability to form exopolysaccharides.They were identified by sequencing of the 16 S rRNA gene, physiological and biochemical properties as Pedobacter sp. 2U-K-37 and Pseudarthrobacter sp. 2B-K-54. In the soil samples from sites of feed and nesting activity of Larus dominicanus microorganisms that metabolize nitrogen of organic compounds were the most numerous. Oligotrophic microorganisms and microorganisms that metabolize nitrogen of inorganic compounds were less numerous. The number of microorganisms of groups in the samples from the soil surface and lower layers differed statistically significant. Isolated and identified obligate psychrophilic strain Pedobacter sp. 2U-K-37 and psychrotolerant strain Pseudarthrobacter sp. 2B-K-54 are moderate halophiles that are able to hydrolyze starch, gelatin, tween-20 and synthesize exopolysaccharides.

Investigating the cultural-morphological features of rhizobacteria and allocating it from the cotton plant (Gossýpium hirsútum): in the example of irrigated meadow soils of Uzbekistan

This paper investigates the cultural-morphological, physiological and biochemical properties of bacterial isolates with stimulating properties isolated from the rhizosphere of cotton (Gossýpium hirsútum) grown in saline soils of Uzbekistan. The cells of the isolated culture No. 12 were found to be rod-shaped, 2-3x0.5-0.6 urn in size, single or chain-linked, Gram-positive aerobic bacteria producing spores. In studying the culture No. 146, its cells were in the form of thick, less mobile rods, 1-2x0.6-0.8 urn in size, forming thermostable spores. The spores were located in the center of the cell; the Gram-stained colonies in meat-peptone agar were round, bulging; the edges were flat, consistency oily, smooth and, mucous; and, the upper part was found to be shiny. Studies have shown that the isolates appertained to the genus Bacillus sr.

Active Antibiotics Production by Actinomycetes Indigenous To Saudi Arabia Soils

Streptomyces are the most popular among the Actinomycetes groups and found in soils worldwide. They form an important part of the soil ecology within the Actinomycetales order. Streptomyces are diverse as secondary antibiotic metabolites such as Novobiocin, Amphotericin, Vancomycin, Neomycin, Gentamicin, Chloramphenicol, Tetracycline, Erythromycin and Nystatin. Thus, the current study was aimed to isolate, identify and assess the active antibiotic metabolites produced by different actinomyces sp. found in Saudi Arabian soils. Six samples were collected from desert soils of the Al Thumamah area and analyzed using GS-MS. Scanning Electron Microscopy was used to identify the bacterial strains along with their antibiotic metabolites effectiveness of secondary metabolites (antibiotics) against different Gram-positive (Bacillus subtilis, Staphylococcus aureus), negative pathogens (Pseudomonas aeruginosa, Escherichia coli, Salmonella suis, and Shigella sonnei) as well as the fungal strain Candida albicans was investigated. Thirty active bacterial (F1-30) strains were isolated from the soil samples and the strains F3, F7, F22, F30 have white, gray, pink, yellow and red colours respectively. Only ten strains (F13, F14, F15, F16, FI7, F18, F19, F20, F21, and F22) were found to have antimicrobial activity against at least one pathogen. The optimum growth environment was pH 4-10, temperature (300C), and NaCl (7% w/v) concentration. According to our findings, the extreme desert environment of Al Thumamah from Saudi Arabia is rich in its actinobacterial population with diverse colouring groups and various physiological and biochemical properties. This shows it’s capability of generating secondary metabolite elements that could inhibit pathogenic microorganisms.

APPLICATION OF METAGENOMICS IN ECOLOGY: A BRIEF OVERVIEW

Starting from the fact that in a microbial community even the concept of species is poorly defined and often debated, but closely related organisms tend to share a substantial amount of genomic sequences, together with a large number of physiological and biochemical properties, it was developed metagenomics. The discipline of metagenomics, defined as the genomic analysis of all microorganisms in a given niche environment, has evolved as an effort to find out more about the microbial diversity of natural environments, such as soil, seawater and the gastrointestinal tract of vertebrates and invertebrates. The purpose of this paper was to bring in front the discipline of metagenomics which will be used in many scientific areas in the future. Our paper represents a brief review of the literature available on the internet regarding the definition, description of metagenomics but also its possibilities of its application in ecology. Moreover, this paper contains the description of MG-RAST software as bioinformatics method that is suitable for usage of metagenomics in ecological studies.