Sun Bangyao, Ma Changgeng, Liang Jiaqing, Yang Zhonghua, Shao Jing, Meng Fanhua, Li Changxue, Yang Ruoting, Yang Xue, Wang Zhitao
School of Medical Laboratory, Shandong Second Medical University, Weifang, 261053, China.
Affiliated Hospital of Shandong Second Medical University, Shandong Second Medical University, Weifang, 261053, China.
BMC Microbiol. 2025 Aug 1;25(1):471. doi: 10.1186/s12866-025-04228-5.
Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has emerged as a significant global public health threat due to its increasing prevalence and dissemination, necessitating the development of novel antimicrobial agents. In this regard, bacteriophages, particularly lytic phages, offer a promising alternative to conventional antibiotics for the treatment of such resistant infections. In this study, we isolated and characterized a lytic Pseudomonas phage, Pa_WF01, from hospital sewage, which specifically targets clinical CRPA strains. The host range, multiplicity of infection (MOI), morphology, one-step growth curve, thermal and pH stability, chloroform sensitivity, and lytic activity of Pa_WF01 were evaluated. Our findings showed that the MOI, latent period, and burst size of Pa_WF01 were approximately 0.0001, 10 min, and 154 phages per cell, respectively. Furthermore, Pa_WF01 exhibited robust lytic activity across a broad range of pH values (4-12) and temperatures (4-50 °C), effectively inhibiting bacterial growth. Transmission electron microscopy (TEM) analysis supported that Pa_WF01 exhibits morphological characteristics similarity to the Schitoviridae family, and the result was further confirmed by phylogenetic analysis of complete genome sequences. Whole-genome sequencing revealed that Pa_WF01 has a double-stranded DNA genome of 73,369 bp and a GC content of 54.78%, containing 94 open reading frames (ORFs). Notably, no tRNA, virulence, or antibiotic resistance genes were identified within the genome. Phylogenetic tree analysis further classified Pa_WF01 as closely related to phages of the Litunavirus genus. In vivo, Pa_WF01 significantly improved the survival rate of mice infected with CRPA, reduced inflammatory responses, decreased bacterial loads in organs (lung, liver, and spleen), and alleviated organ damage. Additionally, in vitro analysis demonstrated that Pa_WF01 enhanced serum-mediated bactericidal activity. Taken together, these results highlight the potential of phage Pa_WF01 as a viable therapeutic alternative for treating CRPA infections in clinical practice.
耐碳青霉烯类铜绿假单胞菌（CRPA）因其日益增加的流行率和传播范围，已成为全球重大的公共卫生威胁，因此需要开发新型抗菌药物。在这方面，噬菌体，特别是裂解性噬菌体，为治疗此类耐药感染提供了一种有前景的替代传统抗生素的方法。在本研究中，我们从医院污水中分离并鉴定了一种裂解性假单胞菌噬菌体Pa_WF01，它特异性靶向临床CRPA菌株。评估了Pa_WF01的宿主范围、感染复数（MOI）、形态、一步生长曲线、热稳定性和pH稳定性、氯仿敏感性以及裂解活性。我们的研究结果表明，Pa_WF01的MOI、潜伏期和裂解量分别约为0.0001、10分钟和每个细胞154个噬菌体。此外，Pa_WF01在广泛的pH值范围（4 - 12）和温度范围（4 - 50°C）内均表现出强大的裂解活性，有效抑制细菌生长。透射电子显微镜（TEM）分析表明Pa_WF01具有与长尾噬菌体科相似的形态特征，全基因组序列的系统发育分析进一步证实了这一结果。全基因组测序显示，Pa_WF01具有一个73369 bp的双链DNA基因组，GC含量为54.78%，包含94个开放阅读框（ORF）。值得注意的是，在基因组中未鉴定到tRNA、毒力或抗生素抗性基因。系统发育树分析进一步将Pa_WF01归类为与Litunavirus属的噬菌体密切相关。在体内，Pa_WF01显著提高了感染CRPA小鼠的存活率，降低了炎症反应，减少了器官（肺、肝和脾）中的细菌载量，并减轻了器官损伤。此外，体外分析表明Pa_WF01增强了血清介导的杀菌活性。综上所述，这些结果突出了噬菌体Pa_WF01作为临床实践中治疗CRPA感染的可行治疗替代方案的潜力。
