Antibacterial Potential with Molecular Docking Study against Multi-Drug Resistant Bacteria and Mycobacterium tuberculosis of Streptomycin Produced by Streptomyces atroverins, strain Askar-SH50

The actinobacterium strains were isolated from marine samples that collected from South Sinai Sharm ElSheikh, Egypt. These isolates were screened for antimicrobial activities in starch nitrate medium. One of the actinomycete isolates (Askar-SH50) was found to produce a broad spectrum antimicrobial activity. Identification of the most potent isolate was performed according to the cell wall chemo-type analysis and spore morphology. From results identification obtained suggested that this strain is a Streptomyces. Further cultural, physiological characteristics and analysis of the nucleotide sequence of 16S rRNA gene evidenced a 99% similarity with Streptomyces atroverins. The isolated strain was eventually identified as Streptomyces atroverins, strain Askar-SH50 and recorded in gene bank with accession number KU740212.The fermentation broth extract of a strain gives one major active compound. The antimicrobial activities of purified active compound showed strong activity against Gram-positive and Gram-negative bacteria. It also, exhibits strong potential towards multi-drug resistant bacteria include Staphylococcus aureus (MRSA), Staphylococcus epidermis, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumonia and Mycobacterium tuberculosis. The results of MIC are listed as: 125 μg/ml, 15.62μg/ml, 3.90 μg/ml, 62.5 μg/ml, 7.81 μg/ml, 3.90 μg/ml and 15.62 μg/ml, respectively. The physicochemical features of the purified antibiotic included solubility, color, melting point, spectroscopic characteristics, elemental analysis, and chemical reactions have been examined. This investigation symbolizes an expected empirical formula of C21H39N7O12. Molecular modeling was performed on streptomycin in order to emphasize its mode of action as an anti TB, and to determine its possible binding interactions with Mycobacterium tuberculosis enoyl-reductase InhA enzyme. In conclusion, the collected data emphasized the fact that the purified antibiotic compound was suggestive of being belonging to streptomycin antibiotic produced by Streptomyces atroverins strain Askar-SH50. Validation of the molecular docking protocol upon Mycobacterium tuberculosis registers that, streptomycin provided from Streptomyces atroverins, strain Askar-SH50 show binds to the amino acid deposits inside the binding pocket among encouraging results.