Differential characterization of two novel antinematodal biological control agents : Streptomyces costaricus sp. nov. and a strain of Bacillus thuringiensis.

Two novel antinematodal strains of bacteria, Streptomyces sp. (CR-43) and Bacillus thuringiensis is (Bt) (CR-371) originating in Costa Rica were differentiated from other closely related strains and compared to rifampicin-resistant derivatives in greenhouse and field studies. The name Streptomyces costaricus is proposed for strain CR-43. The generic attribution was based on its typical morphology, production of LL-diaminopimelic acid and fatty acid composition. To clarify its taxonomic position, the isolate was compared with type strains of similar Streptomyces spp. The results of biochemical tests and profile analysis of hydrolyzable fatty acids indicated that CR-43 differed from previously described species and represents a new species. CR-43 (= ATCC 55274 = NRRL B-16897) is the type strain. A genotaxonomic approach to the differentiation of the streptomycetes was also taken. A modified RAPD analysis, conserved mini-sequence primed PCR (CMSP-PCR), was designed to target short conserved sequences dispersed throughout the streptomycete genome. All species had distinct DNA profiles when DNA was amplified with either 15-mer primer 5SSU3 (5\sp{\prime}-TGCGGCCGTACTCCC) or SSU5 (5\sp{\prime}-CGGCAGGCCTAACAC). The DNA profile of CR-43 resembled most that of S. h. decoyicus using primer SSU5. Species delineation was easily achieved with CMSP-PCR DNA amplification without further enzymatic processing. The differentiation of the novel Bt strain from five patented antinematodal Bt strains was required for patent prosecution. This was achieved by analysis of hydrolyzable fatty acid compositions of the strains by GC-MS and by DNA profile analysis. Thirty compounds in the total ion chromatograms were identified and analyzed using non-parametric statistics, the major fatty acids being i-15:0 (13.7-23.2%), i-13:0 (6.8-10.7%), i-14:0 (5.0-7.7%), 14:0 (3.0-4.1%), a-15:0 (3.9-9.9%), i-16:0 (3.6-7.2%), 16:0 (3.2-11.6%), i-17:0 (3.2-9.8%), 18:0 (tr-13.5%), a monounsaturated C16 (4.5-9.9%), a monounsaturated branched C17 (2.8-5.8%), a diunsaturated C18 (0-5.8%), and a monounsaturated C18 acid (0.3-4.8%). Molecular amplification of the DNA using a random nanomeric primer 5\sp{\prime}-CCGAGTCCA (that could discriminate serovars) showed that RAPD profiles of the Bt\u27s were different. Spontaneous rifampicin-resistance (rif\sp+) was selected in CR-371 and CR-43. Rif\sp+ had a positively pleiotropic effect on the biocontrol activity of the Bt strain and a negatively pleiotropic effect on the novel streptomycete. Rif\sp+ was a useful marker for monitoring survival of CR-371 and CR-43 in soil

Taxonomy and antimicrobial activities of a new Streptomyces sp. TN17 isolated in the soil from an oasis in Tunis

An actinomycete strain referred to as TN17 was screened for its antimicrobial activities. The taxonomic status of this strain was established. The organism was found to have morphological and chemotaxonomic characteristics typical of Streptomycetes. Based on the 16S rRNA nucleotide sequences, Streptomyces sp. TN17 was found to have a relationship with Streptomyces lilaceus, Streptomyces gobitricini and Streptomyces lavendofoliae. Combined analysis of the 16 S rRNA gene sequence (FN687757), phylogenetic analysis, fatty acids profile and physiological tests indicated that there are genotypic and phenotypic differences between TN17 and neighboring Streptomyces species’ neighbors. Therefore, TN17 is a novel species: Streptomyces sp. TN17 (=DSM 42020T=CTM50229T). A cultured extract of this strain inhibits the growth of several Gram positive and Gram negative bacteria and fungi

Taxonomic study and partial characterization of antimicrobial compounds from a moderately halophilic strain of the genus Actinoalloteichus

A moderately halophilic actinomycete strain designated AH97 was isolated from a saline Saharan soil, and selected for its antimicrobial activities against bacteria and fungi. The AH97 strain was identified by morphological, chemotaxonomic and phylogenetic analyses to the genus Actinoalloteichus. Analysis of the 16S rDNA sequence of strain AH97 showed a similarity level ranging between 95.8% and 98.4% within Actinoalloteichus species, with A. hymeniacidonis the most closely related. The comparison of the physiological characteristics of AH97 with those of known species of Actinoalloteichus showed significant differences. Strain AH97 showed an antibacterial and antifungal activity against broad spectrum of microorganisms known to be human and plant pathogens. The bioactive compounds were extracted from the filtrate culture with n-butanol and purified using thin layer chromatography and high pressure liquid chromatography procedures. Two active products were isolated, one hydrophilic fraction (F1) and another hydrophobic (F2). Ultraviolet-visible, infrared, mass and 1H and 13C nuclear magnetic resonance spectroscopy studies suggested that these molecules were the dioctyl phthalate (F2) and an aminoglycosidic compound (F1)

Taxonomy and chemical characterization of antibiotics of Streptosporangium Sg 10 isolated from a Saharan soil

A new actinomycete strain designated Sg 10, producing antimicrobial substances was isolated from an Algerian soil. Morphological and chemical studies indicated that strain Sg 10 belonged to the genus Streptosporangium. The comparison of its physiological characteristics with those of known species of Streptosporangium showed significant differences with the nearest species Streptosporangium carneum. Analysis of the 16S rDNA sequence of strain Sg 10 showed a similarity level ranging between 96.3% and 97.8% within Streptosporangium species, with S. carneum the most closely related. However, the phylogenetic analysis indicated that strain Sg 10 represent a distinct phyletic line suggesting a new genomic species. The antimicrobial activity of strain Sg 10 showed an antibacterial activity against Gram-positive bacteria as well as an antifungal one. Four active products were isolated from the culture broth using various separation procedures. On the basis of UV-VIS spectrometry, infrared spectroscopy and chemical revelations, the antibiotics were classified in the group of glycosylated aromatics

Biocontrol of Damping-Off Disease Caused by Rhizoctonia Solani in Some Medicinal Plants Using Local Strain of Streptomyces Pactum

Abstract: A number of 187 Streptomyces isolates were isolated from different Egyptian soil samples and screened for their antifungal activities (mm inhibition zone) by agar diffusion method, only 5 isolates representing 2.67% produced antifungal metabolites. Starch nitrate agar was the most suitable medium for growth and production of antifungal metabolites by different Streptomyces isolates. In addition, Streptomyces isolate S131 was the most efficient isolate in antifungal activities (mm) which was identified as a strain of Streptomyces pactum. S131 .Furthermore, the most sensitive test organism for antifungal metabolites produced by S. pactum strain S131was Aspergillus niger followed by Fusarium oxysporum, Candida albicans, Aspergillus flavus, Fusarium moniliforme, Rhizoctonia solani and Pythium sp which resulted 20, 17, 16, 15,15, 14 and 13 mm of inhibition zone around agar (6 mm) culture disks of Streptomyces pactum-S131, respectively. Application of cultural filtrate in biocontrol against damping-off caused by Rhizoctonia solani in fennel and coriander seedlings were studied, the results revealed that there were significantly differences among all soil treatments in the percentage of total survival fennel plants from damping-off disease. The maximum percentage of total survival fennel plants from damping-off disease was recorded at uninfested soil treatment followed by soil infested with R. solani + rhizolex, soil infested with R. solani + culture filtrate and soil infested with R. solani, which resulted 82.35, 69.41, 55.50 and 22.28%, respectively. In addition, there were no significantly differences between uninfested soil and soil infested with R. solani + rhizolex in the percentage of total survival coriander plants from damping-off disease, which gave 91.67 and 90.67%, respectively. But there were significantly differences between soil infested with R. solani + culture filtrate of Streptomyces pactum strain S131 and soil infested with R. solani only in the percentage of total survival coriander plants from damping-off disease, which gave 58.34 and 11.09%, respectively

Antibiotic biosynthesis pathways from endophytic streptomyces SUK 48 through metabolomics and genomics approaches

Streptomyces sp. has been known to be a major antibiotic producer since the 1940s. As the number of cases related to resistance pathogens infection increases yearly, discovering the biosynthesis pathways of antibiotic has become important. In this study, we present the streamline of a project report summary; the genome data and metabolome data of newly isolated Streptomyces SUK 48 strain are also analyzed. The antibacterial activity of its crude extract is also determined. To obtain genome data, the genomic DNA of SUK 48 was extracted using a commercial kit (Promega) and sent for sequencing (Pac Biosciences technology platform, Menlo Park, CA, USA). The raw data were assembled and polished using Hierarchical Genome Assembly Process 4.0 (HGAP 4.0). The assembled data were structurally predicted using tRNAscan-SE and rnammer. Then, the data were analyzed using Kyoto Encyclopedia of Genes and Genomes (KEGG) database and antiSMASH analysis. Meanwhile, the metabolite profile of SUK 48 was determined using liquid chromatographymass spectrophotometry (LC-MS) for both negative and positive modes. The results showed that the presence of kanamycin and gentamicin, as well as the other 11 antibiotics. Nevertheless, the biosynthesis pathways of aurantioclavine were also found. The cytotoxicity activity showed IC50 value was at 0.35 � 1.35 mg/mL on the cell viability of HEK 293. In conclusion, Streptomyces sp. SUK 48 has proven to be a non-toxic antibiotic producer such as auranticlavine and gentamicin

Underground Cordon by Microorganisms-Part-III Role of Soil Inhabiting Actinomycetes

Certain strains of soil inhabiting actinomycetes were found to substantially corrode aluminium alloy (54-S) which has bscn found tobe more resistant to bacterial or fungal corrosion in our earlier studies.These strains did not produce any corrosion on the mild steel and galvanised iron panels which were heavily corroded by bacteria and fungi. The corrosive isolates have been partialiy characterised after their isolation and purification. The extent of corrosion caused by eachstrain has been determined

Fermentasi dan Karakterisasi Antibiotik T1O81MY1O-B Asal Streptoverticillium olivorticuly

Sejak penemuan Streptomisin oleh Waksman 1994, maka perkembangan penelitian yang mengarah pada penemuan antibiotika baru terus dikembangkan. Hingga saat ini antibiotika masih tetap merupakan obat produk mikroorganisme pilihan dan memegang peranan yang penting dalam pengobatan penyakit infeksi. Penelitian ini bertujuan untuk memproduksi antibio??tika yang diperoleh dari proses fermentasi, memanfaatkan jasa Streptoverticillium olivoriticuly dengan cara pengocokan menggunakan "reciprocal shaker", T1O81MY1O-B diperoleh dengan mengisolasi kaldu fermentasi dengan sentrifugasi dan penyaringan untuk memisahkan miselia dari filtrat. kemudian bagian miselia diekstraksi menggunakan MeOH dan AcOEt. Pemurnian dilakukan dengan kromatografi kolom, dimana aktivitas komponen aktifnya selama proses fermentasi, ekstraksi dan pemurnian dideteksi menggunakan Candida albicans Yu1200 sebagai mikroorganisme uji. T1O81MY1O-B berupa bubuk warna putih, titik leleh 61 ??? 64?? C. Larut dalam etil asetat, etanol, kloroform dan eter, tidak larut dalam air, heksan dan petroleum eter. Larutannya tidak stabil pada larutan alkali. Analisis spektrofotometer ultra violet menunjukkan serapan pada 213 nm (CH3OH) dan 236 nm (NaOH). Sedang analisis spektrofotometer infra merah menunjukkan adanya gugusan hidroksi pada bilangan gelombang 3250 cm, metil pada 2920 cm dan ikatan rangkap -C=CH- pada 1650 cm-1. Aktivitas antimikroorganisme khas pada Trichophyton asteriodes, filtenaria kikuchiana dan Helminthosporium oryzae

Identification and Antibiosis of a Novel Actinomycete Strain RAF-11 Isolated From Iraqi Soil.

A total of 35 actinomycetes strains were isolated from and around Baghdad, Iraq, at a depth of 5-10 m, by serial dilution agar plating method