Department of Microbiology, Faculty of Science, Ain Shams University, Abbassia, Cairo, 11566, Egypt.
Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Hadayek Shubra 11241, Qalibia, Egypt.
BMC Microbiol. 2023 Apr 26;23(1):118. doi: 10.1186/s12866-023-02847-4.
In areas with limited water resources, the reuse of treated drainage water for non-potable purposes is increasingly recognised as a valuable and sustainable water resource. Numerous pathogenic bacteria found in drainage water have a detrimental impact on public health. The emergence of antibiotic-resistant bacteria and the current worldwide delay in the production of new antibiotics may make the issue of this microbial water pollution even more challenging. This challenge aided the resumption of phage treatment to address this alarming issue. In this study, strains of Escherichia coli and Pseudomonas aeruginosa and their phages were isolated from drainage and surface water from Bahr El-Baqar and El-Manzala Lake in Damietta governorate, Egypt. Bacterial strains were identified by microscopical and biochemical examinations which were confirmed by 16 S rDNA sequencing. The susceptibility of these bacteria to several antibiotics revealed that most of the isolates had multiple antibiotic resistances (MAR). The calculated MAR index values (> 0.25) categorized study sites as potentially hazardous to health. Lytic bacteriophages against these multidrug-resistant strains of E. coli and P. aeruginosa were isolated and characterized. The isolated phages were found to be pH and heat stable and were all members of the Caudovirales order as recognized by the electron microscope. They infect 88.9% of E. coli strains and 100% of P. aeruginosa strains examined. Under laboratory conditions, the use of a phage cocktail resulted in a considerable reduction in bacterial growth. The removal efficiency (%) for E. coli and P. aeruginosa colonies increased with time and maximized at 24 h revealing a nearly 100% reduction after incubation with the phage mixture. The study candidates new phages for detecting and controlling other bacterial pathogens of public health concern to limit water pollution and maintain adequate hygiene.
在水资源有限的地区，越来越多的人认识到将处理后的排水再用于非饮用水用途是一种有价值且可持续的水资源。排水中存在的许多病原体对公共健康有不利影响。抗药性细菌的出现以及目前全球新抗生素生产的延迟，可能使这个微生物水污染问题更加具有挑战性。这一挑战促使人们重新采用噬菌体治疗来解决这一令人担忧的问题。在这项研究中，从埃及达米埃塔省的 Bahr El-Baqar 和 El-Manzala 湖的排水和地表水分离出了大肠杆菌和铜绿假单胞菌及其噬菌体。通过显微镜和生化检查鉴定了细菌菌株，并用 16S rDNA 测序进行了确认。这些细菌对几种抗生素的敏感性表明，大多数分离株具有多重抗生素耐药性（MAR）。计算出的 MAR 指数值（>0.25）表明研究地点对健康有潜在危害。分离出了针对这些多药耐药大肠杆菌和铜绿假单胞菌菌株的裂解噬菌体，并对其进行了表征。分离出的噬菌体具有酸碱稳定性和热稳定性，并且通过电子显微镜都被归类为长尾病毒目成员。它们可以感染 88.9%的大肠杆菌菌株和 100%的铜绿假单胞菌菌株。在实验室条件下，噬菌体混合物的使用导致细菌生长显著减少。大肠杆菌和铜绿假单胞菌菌落的去除效率（%）随时间增加而增加，并在 24 小时时达到最大值，表明在与噬菌体混合物孵育后，减少了近 100%。该研究为检测和控制其他公共卫生关注的细菌病原体提供了新的噬菌体候选物，以限制水污染并保持足够的卫生水平。
