Akbar N, Siddiqui R, Iqbal M, Sagathevan K, Khan N A
Department of Biological Sciences, School of Science and Technology, Sunway University, Bandar Sunway, Malaysia.
National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan.
Lett Appl Microbiol. 2018 May;66(5):416-426. doi: 10.1111/lam.12867. Epub 2018 Mar 25.
Here, we hypothesized that the microbial gut flora of animals/pests living in polluted environments, produce substances to thwart bacterial infections. The overall aim of this study was to source microbes inhabiting unusual environmental niches for potential antimicrobial activity. Two cockroach species, Gromphadorhina portentosa (Madagascar) and Blaptica dubia (Dubia) were selected. The gut bacteria from these species were isolated and grown in RPMI 1640 and conditioned media were prepared. Conditioned media were tested against a panel of Gram-positive (Methicillin-resistant Staphylococcus aureus, Streptococcus pyogenes, Bacillus cereus) and Gram-negative (Escherichia coli K1, Salmonella enterica, Serratia marcescens, Pseudomonas aeruginosa, Klebsiella pneumoniae) bacteria, as well as the protist pathogen, Acanthamoeba castellanii. The results revealed that the gut bacteria of cockroaches produce active molecule(s) with potent antibacterial properties, as well as exhibit antiamoebic effects. However, heat-inactivation at 95°C for 10 min had no effect on conditioned media-mediated antibacterial and antiamoebic properties. These results suggest that bacteria from novel sources i.e. from the cockroach's gut produce molecules with bactericidal as well as amoebicidal properties that can ultimately lead to the development of therapeutic drugs.
The bacteria isolated from unusual dwellings such as the cockroaches' gut are a useful source of antibacterial and antiamoebal molecules. These are remarkable findings that will open several avenues in our search for novel antimicrobials from unique sources. Furthermore studies will lead to the identification of molecules to develop future antibacterials from insects.
在此，我们假设生活在污染环境中的动物/害虫的肠道微生物群会产生物质来抵御细菌感染。本研究的总体目标是从栖息于特殊环境生态位的微生物中寻找潜在的抗菌活性。选择了两种蟑螂，即马达加斯加发声蟑螂（Gromphadorhina portentosa）和杜比亚蟑螂（Blaptica dubia）。分离出这些蟑螂的肠道细菌，并在RPMI 1640培养基中培养，制备条件培养基。将条件培养基针对一组革兰氏阳性菌（耐甲氧西林金黄色葡萄球菌、化脓性链球菌、蜡样芽孢杆菌）、革兰氏阴性菌（大肠杆菌K1、肠炎沙门氏菌、粘质沙雷氏菌、铜绿假单胞菌、肺炎克雷伯菌）以及原生生物病原体卡氏棘阿米巴进行测试。结果显示，蟑螂的肠道细菌会产生具有强效抗菌特性的活性分子，并且还具有抗阿米巴作用。然而，在95°C下加热灭活10分钟对条件培养基介导的抗菌和抗阿米巴特性没有影响。这些结果表明，来自新来源（即蟑螂肠道）的细菌会产生具有杀菌和杀阿米巴特性的分子，这最终可能会促成治疗药物的研发。
从蟑螂肠道等特殊栖息地分离出的细菌是抗菌和抗阿米巴分子的有用来源。这些显著的发现将为我们从独特来源寻找新型抗菌剂开辟多条途径。进一步的研究将有助于鉴定分子，以便从昆虫中开发未来的抗菌药物。
