Laboratoire de Microbiologie Appliquée à l'Agro-alimentaire, Au Biomédical et à l'Environnement (LAMAABE), Département de Biologie, Université Abou Bekr Belkaid, BP 119, Imama, 13000 Tlemcen, Algeria.
Laboratoire des Produits Naturels (LAPRONA), Département de Biologie, Université Abou Bekr Belkaid, BP 119, Imama, 13000 Tlemcen, Algeria.
J Infect Public Health. 2021 Nov;14(11):1671-1678. doi: 10.1016/j.jiph.2021.09.019. Epub 2021 Sep 30.
The constant development of microbial resistance to the traditional antimicrobial agents and the emergence of new infectious diseases justify the urgent need for new effective antimicrobial molecules. However, the irrational use of antibiotics increases microbial resistance dramatically and along with that the frequency of mortality associated with infections is higher. Therefore, to combat the antimicrobial resistance, the screening of compounds with novel chemical structures is essential. This study intended to determine the antimicrobial potential of Streptomyces GLD22 strain isolated from Algeria.
The characterization of Streptomyces strain GLD22 was performed by physiological, biochemical and molecular tests. The antimicrobial activity was tested by the well diffusion method and the minimum inhibitory concentration value calculation were performed using broth micro dilution technique. The extracellular metabolites profiling was done using GC-MS.
Physiological, biochemical and phylogenetic analysis confirmed that the strain GLD22 showed maximum identity towards Streptomyces species. The extra cellular metabolites revealed their antimicrobial activity at 1 mg/ml for Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, whereas Staphylococcus aureus, Bacillus cereus and Bacillus subtilis documented 0.5, 1 and 1 mg/ml respectively. GC-MS analysis confirmed that 2-tert-butyl-4,6-bis(3,5-di-tert-butyl-4-hydroxybenzyl) phenol, Dibutyl phthalate and Cyclo(leucyloprolyl) were the major drug molecules present in the extract.
The novel Streptomyces strain GLD22 recovered from the Gueldaman cave of Algeria showed better antimicrobial activity towards both Gram positive and Gram negative pathogens. Interestingly, the MIC values were comparable with the standard drug molecules. In addition, the identification of active metabolites present in the crude extracts was an advantage.
传统抗菌剂的微生物耐药性不断发展和新传染病的出现，使得急需寻找新的有效抗菌分子。然而，抗生素的不合理使用导致微生物耐药性急剧增加，感染相关死亡率也随之升高。因此，为了对抗抗菌耐药性，筛选具有新颖化学结构的化合物至关重要。本研究旨在确定从阿尔及利亚分离出的链霉菌 GLD22 菌株的抗菌潜力。
通过生理、生化和分子试验对链霉菌 GLD22 菌株进行鉴定。采用孔扩散法检测抗菌活性，采用肉汤微量稀释技术计算最小抑菌浓度值。采用 GC-MS 对细胞外代谢产物进行分析。
生理生化和系统发育分析证实，菌株 GLD22 与链霉菌属的亲缘关系最为密切。细胞外代谢产物在 1mg/ml 时对肺炎克雷伯菌、铜绿假单胞菌和大肠杆菌表现出抗菌活性，而金黄色葡萄球菌、蜡状芽孢杆菌和枯草芽孢杆菌的最低抑菌浓度分别为 0.5、1 和 1mg/ml。GC-MS 分析证实，2-叔丁基-4,6-双(3,5-二叔丁基-4-羟基苄基)苯酚、邻苯二甲酸二丁酯和环(亮氨酰脯氨酰)是提取物中主要的药物分子。
从阿尔及利亚 Gueldaman 洞穴中分离出的新型链霉菌 GLD22 对革兰氏阳性和革兰氏阴性病原体均表现出较好的抗菌活性。有趣的是，MIC 值与标准药物分子相当。此外，鉴定粗提物中存在的活性代谢物是一个优势。
