Tariq Muhammad Usama, Muzammil Saima, Ashfaq Usman Ali, Arshad Muhammad Imran, Shafique Muhammad, Ejaz Hasan, Khurshid Mohsin, Eltayeb Lienda Bashier, Mazhari Bi Bi Zainab, Elamir Mohammed Yagoub Mohammed, Al-Harthi Helal F, Rasool Muhammad Hidayat, Aslam Bilal
Institute of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan.
Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan.
Vet World. 2024 Sep;17(9):2008-2016. doi: 10.14202/vetworld.2024.2008-2016. Epub 2024 Sep 8.
The dearth of new antibiotics necessitates alternative approaches for managing infections caused by resistant superbugs. This study aimed to evaluate the lytic potential of the purified bacteriophage PKp-V1 against extended-spectrum β-lactamase (ESBL) harboring hypervirulent (hvKp)-K1 recovered from veterinary specimens.
A total of 50 samples were collected from various veterinary specimens to isolate , followed by antimicrobial susceptibility testing and molecular detection of various virulence and ESBL genes. Multilocus sequence typing of the isolates was performed to identify prevalent sequence types. The bacteriophages were isolated using the double-agar overlay method and characterized using transmission electron microscopy, spot tests, plaque assays, stability tests, and one-step growth curve assays.
Among 17 (34%) confirmed isolates, 6 (35%) were hvKp, whereas 13 (76%) isolates belonging to the K1 type were positive for the wzy (K1) virulence gene. All (100%) hvKp isolates exhibited the allelic profile of ST258. Overall, PKp-V1 exhibited an 88 % (15/17; (p ≤ 0.05) host range, among which all (100 %; p ≤ 0.01) hvKp isolates were susceptible to PKp-V1. PKp-V1 exhibited a lytic phage titer of 2.4 × 10 plaque forming unit (PFU)/mL at temperatures ranging from 25°C to 37°C. The lytic phage titers of PKp-V1 at pH = 8 and 0.5% chloroform were 2.1 × 10 PFU/mL and 7.2 × 10 PFU/mL, respectively.
Although the incidence of ESBL-infected in veterinary settings is worrisome, PKp-V1 phages showed considerable lytic action against the host bacterium, indicating the potential of PKp-V1 as a possible alternative therapeutic option against MDR .
新型抗生素的匮乏使得有必要采用替代方法来应对由耐药超级细菌引起的感染。本研究旨在评估纯化的噬菌体PKp-V1对从兽医标本中分离出的携带超广谱β-内酰胺酶（ESBL）的高毒力（hvKp）-K1的裂解潜力。
从各种兽医标本中总共收集了50个样本以进行分离，随后进行抗菌药敏试验以及各种毒力和ESBL基因的分子检测。对分离株进行多位点序列分型以鉴定流行的序列类型。使用双层琼脂覆盖法分离噬菌体，并通过透射电子显微镜、点滴试验、噬菌斑测定、稳定性试验和一步生长曲线试验对其进行表征。
在17株（34%）确诊的分离株中，6株（35%）为hvKp，而属于K1型的13株（76%）分离株的wzy（K1）毒力基因为阳性。所有（100%）hvKp分离株均表现出ST258的等位基因谱。总体而言，PKp-V1表现出88%（15/17；p≤0.05）的宿主范围，其中所有（100%；p≤0.01）hvKp分离株对PKp-V1敏感。PKp-V1在25°C至37°C的温度范围内表现出2.4×10噬菌斑形成单位（PFU）/mL的裂解噬菌体效价。PKp-V1在pH = 8和0.5%氯仿条件下的裂解噬菌体效价分别为2.1×10 PFU/mL和7.2×10 PFU/mL。
尽管兽医环境中ESBL感染的发生率令人担忧，但PKp-V1噬菌体对宿主细菌表现出相当大的裂解作用，表明PKp-V1作为对抗多重耐药菌的一种可能的替代治疗选择的潜力。
