Ananna Nishat Tasnim, Shishir Tushar Ahmed, Ahmed Akash, Al Sium Syed Muktadir, Shakil Md Salman, Haque Fahim Kabir Monjurul, Hasanuzzaman Md
Biotechnology Program, Department of Mathematics and Natural Sciences, BRAC University, Dhaka, Bangladesh.
Microbiology Program, Department of Mathematics and Natural Sciences, BRAC University, Dhaka, Bangladesh.
Virus Res. 2024 Dec;350:199491. doi: 10.1016/j.virusres.2024.199491. Epub 2024 Nov 9.
Bacteriophages or bacteria infecting viruses are genetically diverse. Due to the emergence of antimicrobial-resistant bacteria, lytic bacteriophages are gaining enormous attention for treating superbug infections. Klebsiella pneumoniae is one of the eight most significant nosocomial pathogens and is addressed as a critical priority pathogen by WHO, requiring alternative treatment options. We reported two highly lytic bacteriophages, Klebsiella phage Kpn BM7 and the novel Klebsiella phage Kpn BU9, isolated from hospital wastewater and exhibiting lytic activity against different clinical isolates. Whole-genome analysis revealed that phages BM7 and BU9 belong to class Caudoviricetes. Phage BM7, with a genome length of 170,558 bp, is a member of the genus Marfavirus and the species Marfavirus F48. While phage BU9, with a genome length of 60,450 bp, remains unclassified. Neither phage harbors any lysogenic, toxin, or antimicrobial resistance genes. Both phages can steadily survive up to 40 °C and at pH 5-7. The optimal MOI was 0.1 for BM7 and 1 for BU9, with short latent periods of 10 and 25 min and burst sizes of 85 PFU/cell and 12 PFU/cell, respectively. This is the first carbapenem-resistant K. pneumoniae targeting lytic phages to be reported from Bangladesh. This study suggests that BM7 and BU9 are potential candidates for targeting carbapenem-resistant K. pneumoniae.
噬菌体或细菌感染性病毒具有遗传多样性。由于抗菌耐药细菌的出现，裂解性噬菌体在治疗超级细菌感染方面正受到极大关注。肺炎克雷伯菌是八大最重要的医院感染病原体之一，世界卫生组织将其列为关键优先病原体，需要替代治疗方案。我们报告了两种高度裂解性的噬菌体，肺炎克雷伯菌噬菌体Kpn BM7和新型肺炎克雷伯菌噬菌体Kpn BU9，它们从医院废水中分离出来，对不同临床分离株表现出裂解活性。全基因组分析表明，噬菌体BM7和BU9属于有尾噬菌体目。噬菌体BM7基因组长度为170,558 bp，是马尔法病毒属和马尔法病毒F48种的成员。而噬菌体BU9基因组长度为60,450 bp，仍未分类。两种噬菌体均未携带任何溶原性、毒素或抗菌耐药基因。两种噬菌体在40°C以及pH值为5至7的条件下都能稳定存活。BM7的最佳感染复数为0.1，BU9为1，潜伏期分别为10分钟和25分钟，爆发量分别为85个噬菌斑形成单位/细胞和12个噬菌斑形成单位/细胞。这是孟加拉国首次报道针对耐碳青霉烯类肺炎克雷伯菌的裂解性噬菌体。这项研究表明，BM7和BU9是针对耐碳青霉烯类肺炎克雷伯菌的潜在候选物。
