Members Of Actinomycetes Research Articles

Combination and improvement of conventional DNA extraction methods in Actinobacteria to obtain high-quantity and high-quality DNA.

Background and Objectives:DNA extraction is an important step of any molecular experiment. DNA could not be easily extracted from members of actinomycetes by the usual methods of lysis. Due to the low efficiency of the conventional DNA extraction methods, development of an effective technique for DNA extraction of actinobacteria in emergency cases seems to be necessary. Since most of the DNA extraction techniques and commercial kits are not efficient enough to extract DNA from actinobacteria, this study was conducted to improve an efficient method obtained from conventional one to extract DNA from this group of bacteria.Materials and Methods:DNA extraction was performed using five methods (an improved method, Invisorb Spin Plant Mini Kit, EZ-10 Spin Column, Sarrbrucken method (HZI, Germany) and Kirby Bauer’s method). To evaluate the quantity and quality of extracted genomic DNA, UV absorbance of all samples and efficiency of polymerase chain reaction (PCR) were evaluated.Results:Overall, the results revealed that the highest quantity (up to 4000 ng/μl) and good quality of DNA was obtained using introduced DNA extraction method.Conclusion:Results indicated that recently introduced improved method was more efficient for extraction of DNA from actinobacteria for DDH (DNA–DNA hybridization) test and for those require the high concentration of DNA.

Actinomycetes Isolation from Forest Soils and Determination of Biological Activities

Actinomycetes bacterial group has the one of the most populous population in microorganisms that extends very different and extensive habitats on earth especially main character of the natural soil habitats. Since old times, bioactive metabolites of soil microorganisms have studied and the results have provided that metabolites these microorganisms have significant benefits to science, medicine, agriculture and pharmaceutical industry. In this study, isolation of Actinomycetes strains from forest soils, identification of morpohological and molecular features, extraction the bioactive metabolite of isolates and determination the antimicrobial, antibiofilm and cytotoxicity activities of bioactive extract was tested. The microbiological isolation methods for collected forest soil samples were used and after the determination of their morphological and molecular features, isolates were defined as Brevibacterium spp. that is member of Actinomycetes. The antibiotic resistance of the isolates were determined by different methods and different concentrations of standard antibiotics. The chromium tolerance of isolates were also determined. The bioactive metabolites of isolates were produced in modified medium and extracted. The antimicrobial, antibiofilm, cytotoxicity activities of bioactive metabolite were determined against standard microorganisms and Artemia salina larvae were used as test organism for cytotoxicity tests. In the present study, results gave informations about Actinomycetes that isolated from forest soils. Isolates have antibiotic resistance and chromium tolerance abilities. And also, showed, Actinomycetes group is the largest bioactive metabolite producing group both antibacterial, antifungal and also a wide range of other compounds such as antibiofilm and cytotoxic compounds. The antimicrobial (MIC) concentrations of bioactive metabolite 2500 μg/mL for standard bacteria cultures and 1250 μg/mL for yeasts. The antibiofilm (MBEC) value was determined at 1250 μg/mL. The 2500 μg/mL concentration of extract was found the effective cytotoxic value. The results are provided that the Brevibacterium spp. isolates have industrial and pharmaceutical potential and more detailed pharmaceutical researchs are planned.

Isolation and Characterization of Plant Growth Promoting Rhizobacteria from Ipomoea sp. Rhizospheres Growing in Iron Sand Soil

Iron sand field, is mostly found along the Indonesia coast. It has low organic matter, contains 38-59% iron (Fe) and sand particles. These characteristics can be called as extreme environments, however there are bacteria capable of growing and surviving in such habitats. Several genera are known as PGPR agents such as Rhizobium, Azospirillum, Azotobacter and Pseudomonas. The research objectives were to measure total population of bacteria from rhizosphere of Ipomoea sp. in iron sand soils, to investigate the ability of bacterial isolates capable of fixing nitrogen, solubilizing phosphate, and producing plant growth hormone such as IAA, and to identify plant growth promoting rhizobacteria isolated from plant rhizospheres candidates growing in iron sand soils. Isolation on NA medium showed that the population were ranged from 1.59 x 105 to 5.2 x 105 CFU.g-1. There were 22 bacterial isolates originated from the media of Ashby, Caceres, and Pikovskaya. Six isolates (A4, A10, C10, P2, P3, and P4) showed high ability to fix nitrogen, solubilize phosphate, and produce IAA. Isolate P4 grew in nitrogen fixing and phosphate solubilizing assay as well as IAA producing. It showed high value of phosphate index (275 mm). Bacterial identification indicated that four isolates (C10, P2, P3, P4) were species members of genus Bacillus and two isolates (A4, A10) were identified as species members of Actinomycetes.

Extreme Processing Conditions Applied in Selection of Different Microorganisms Utilized as Compost Enhancers

Present study included isolation of microorganisms during the mesophilic stage of composting and their reuse in compost mixture to enhance organic matter degradation. Effect of microorganism addition on compost degradation was investigated in the presence of microorganisms obtained by isolation from a miniscule composting system. Effects of water addition and time of mixing were applied as extreme composting conditions. Isolates were obtained from these systems and inoculated to determine the most resistant microorganisms. 16S rRNA sequencing of selected strains indicated the presence of Escherichia, Enterococcus and Streptomyces genus. These microorganisms were added to a large-scale compost mixture to accelerate degradation of organic matter. Results indicated 20 and 38% decreases of organic matter in the sole utilization of Streptomyces sp. K1P07 and ternary utilization at the end of 14 days. Escherichia and Enterococcus inhibited degradation in the case of binary utilization. Isolation of microorganisms from the original flora of the compost mixture had accelerated composting due to interaction among themselves. Member of Actinomycetes, in particular, was shown to be effective even in the case of sole utilization. Higher amounts of biomass-oriented wastes could be removed since composting would be terminated in shorter times with the use of these microorganisms.

ISOLATION OF MARINE BACTERIA IN AMBON BAY WITH POTENTIAL BIOTECHNOLOGICAL FEATURES

Ambon Bay is situated in the Wallacea biogeographical area. Despite various studies on marine natural resources reported from this bay, limited information is available on marine bacteria that produce compounds with potential biotechnological applications. We report here preliminary results of our attempt to isolate bacteria of this group from Ambon Bay. Nine different isolates were obtained, but only eight indicated potential as producers of compounds with biotechnological potential. Two isolates indicated agarolytic bacteria characteristics, whereas one showed the properties of exopolysaccharide (EPS) producing bacteria. Three isolates produced various pigments. Two were identified tentatively as members of actinomycetes, a group known as a prolific producer of antimicrobial compounds. Preliminary identification of the cell morphologies of each isolate revealed the dominance of cocci-shaped bacteria. Most of them showed optimal growth in 1 to 7 days when incubated at 30°C. These results indicate that Ambon Bay waters and the surrounding area could harbour marine bacteria with potential features for biotechnological applications.

GEOGRAPHICAL AND GENETIC DIVERSITY OF HEPATITIS B VIRUS IN THE WALLACEA, INDONESIA

Ambon Bay is situated in the Wallacea biogeographical area. Despite various studies on marine natural resources reported from this bay, limited information is available on marine bacteria that produce compounds with potential biotechnological applications. We report here preliminary results of our attempt to isolate bacteria of this group from Ambon Bay. Nine different isolates were obtained, but only eight indicated potential as producers of compounds with biotechnological potential. Two isolates indicated agarolytic bacteria characteristics, whereas one showed the properties of exopolysaccharide (EPS) producing bacteria. Three isolates produced various pigments. Two were identified tentatively as members of actinomycetes, a group known as a prolific producer of antimicrobial compounds. Preliminary identification of the cell morphologies of each isolate revealed the dominance of cocci-shaped bacteria. Most of them showed optimal growth in 1 to 7 days when incubated at 30°C. These results indicate that Ambon Bay waters and the surrounding area could harbour marine bacteria with potential features for biotechnological applications.

Selective Isolation and Screening of Soil Microorganisms for Metabolites with Herbicidal Potential

Summary Crop losses from weeds worldwide average 10% annually. Herbicide application is almost essential in modern agriculture to maintain high productivity. Increased awareness of the environmental damage caused by continued use of conventional synthetic herbicides has aroused great interest in biodegradable, selective and environmentally friendly herbicides. The increasing incidence of herbicide resistance in weeds has stimulated research for herbicidal compounds with new or novel sites and modes of action. Microbial metabolites have become the focus of attention of researchers searching for natural product alternatives to conventional herbicides. Two well-known commercial herbicides of microbial origin are anisomycin (commercial analogue, methoxyphenon) and bialaphos. Both were isolated from members of actinomycetes. Several phytotoxins have been isolated from microbial metabolites, e.g., herbicidins A and B, herbimycins A and B, nigericin, tentoxin and others. The list of microbial phytotoxins continu...