Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
Institute of Virology, Helmholtz Center Munich and Technical University of Munich, 85764, Neuherberg, Bavaria, Germany.
BMC Microbiol. 2021 May 1;21(1):132. doi: 10.1186/s12866-021-02197-z.
P. aeruginosa is the primary source of hospital-acquired infections. Unfortunately, antibiotic resistance is growing to precariously high levels, making the infections by this pathogen life-threatening and hard to cure. One possible alternative to antibiotics is to use phages. However, the isolation of phages suitable for phage therapy- be lytic, be efficient, and have a broad host range -against some target bacteria has proven difficult. To identify the best places to look for these phages against P. aeruginosa we screened hospital sewages, soils, and rivers in two cities.
We isolated eighteen different phages, determined their host range, infection property, and plaque morphology. We found that the sewage and sewage-contaminated environments are the most reliable sources for the isolation of Pseudomonas phages. In addition, phages isolated from hospital sewage showed the highest efficiency in lysing the bacteria used for host range determination. In contrast, phages from the river had larger plaque size and lysed bacteria with higher levels of antibiotic resistance.
Our findings provided additional support for the importance of sewage as the source of phage isolation.
铜绿假单胞菌是医院获得性感染的主要来源。不幸的是,抗生素耐药性正在上升到危险的高水平,使得这种病原体引起的感染具有致命性且难以治愈。抗生素的一种可能替代品是噬菌体。然而,分离适合噬菌体治疗的噬菌体——溶原性、高效且宿主范围广——针对某些目标细菌已被证明很困难。为了确定针对铜绿假单胞菌的这些噬菌体的最佳寻找地点,我们在两个城市筛选了医院污水、土壤和河流。
我们分离出了十八种不同的噬菌体,确定了它们的宿主范围、感染特性和噬菌斑形态。我们发现,污水和受污水污染的环境是分离假单胞菌噬菌体的最可靠来源。此外,从医院污水中分离出的噬菌体在裂解用于宿主范围确定的细菌方面效率最高。相比之下,来自河流的噬菌体噬菌斑较大,并且能够裂解具有更高水平抗生素耐药性的细菌。
我们的发现进一步支持了污水作为噬菌体分离源的重要性。