Hussain A, Rather M A, Shah A M, Bhat Z S, Shah A, Ahmad Z, Parvaiz Hassan Q
Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Srinagar, India.
Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Jammu Tawi, India.
Lett Appl Microbiol. 2017 Sep;65(3):256-264. doi: 10.1111/lam.12773.
A distinctive screening procedure resulted in the isolation and identification of antituberculotic actinobacteria. In this course, a total of 125 actinobacteria were isolated from various soil samples from untapped areas in Northwestern Himalayas, India. The antibacterial screening showed that 26 isolates inhibited the growth of at least one of the tested bacterial pathogens including Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Bacillus subtilis (ATCC 11774), Micrococcus luteus (ATCC 10240), Escherichia coli (10536), Pseudomonas aeruginosa (ATCC 10145) and Klebsiella pneumonia (ATCC BAA-2146). The production media was optimized for the active strains by estimation of their extract value by the quantification of the ethyl acetate extract. The screening of fermentation products from the selected 26 bioactive isolates revealed that 10 strains have metabolites antagonistic against the standard H37Rv strain of Mycobacterium tuberculosis. The characterization by 16S rRNA gene sequencing and phylogenetic analysis demonstrated the diverse nature of these antituberculosis strains. The secondary metabolites of potent, rare strain, Lentzea violacea AS08 exhibited promising antituberculosis activity with minimal inhibitory concentration (MIC) of 3·9 μg ml . The metabolites identified by gas chromatography-mass spectrometry (GC-MS) included, Phenol, 2,5-bis (1, 1-dimethylethyl), n-Hexadecanoic acid, Hexadecanoic acid methyl-ester, Hexadecanoic acid ethyl-ester and, 9,12-Octadecadienoyl chloride(Z,Z) are biologically significant molecules.
The study presents the isolation of rare actinobacteria from untapped sites in the Northwestern Himalayas and their in vitro potential against Mycobacterium tuberculosis for their metabolites. The study revealed that exploring the untapped natural sources as one of the resourceful approaches for the discovery of new natural products. This study also provided strong evidence for the ability of rare and potent actinobacterial strains to produce bioactive compounds with antagonistic activity and these metabolites can be studied for inhibitory potential.
一种独特的筛选程序导致了抗结核放线菌的分离和鉴定。在此过程中，从印度喜马拉雅西北部未开发地区的各种土壤样本中总共分离出125株放线菌。抗菌筛选表明，26株分离物抑制了至少一种受试细菌病原体的生长，这些病原体包括金黄色葡萄球菌（ATCC 25923）、表皮葡萄球菌（ATCC 12228）、枯草芽孢杆菌（ATCC 11774）、藤黄微球菌（ATCC 10240）、大肠杆菌（10536）、铜绿假单胞菌（ATCC 10145）和肺炎克雷伯菌（ATCC BAA - 2146）。通过对乙酸乙酯提取物进行定量来估计活性菌株的提取物值，从而对生产培养基进行了优化。对所选的26株生物活性分离物的发酵产物进行筛选后发现，有10株菌株的代谢产物对结核分枝杆菌的标准H37Rv菌株具有拮抗作用。通过16S rRNA基因测序和系统发育分析进行的表征证明了这些抗结核菌株的多样性。强效稀有菌株紫丁香伦茨氏菌AS08的次生代谢产物表现出有前景的抗结核活性，最低抑菌浓度（MIC）为3.9μg/ml。通过气相色谱 - 质谱联用（GC - MS）鉴定出的代谢产物包括2,5 - 双（1,1 - 二甲基乙基）苯酚、正十六烷酸、十六烷酸甲酯、十六烷酸乙酯以及9,12 - 十八碳二烯酰氯（Z,Z），这些都是具有生物学意义的分子。
该研究展示了从喜马拉雅西北部未开发地点分离出稀有放线菌及其代谢产物对结核分枝杆菌的体外潜力。该研究表明，探索未开发的天然来源是发现新天然产物的有效方法之一。这项研究还为稀有强效放线菌菌株产生具有拮抗活性的生物活性化合物的能力提供了有力证据，并且可以对这些代谢产物的抑制潜力进行研究。
