Key Laboratory of Tropical Translational Medicine of Ministry of Education, NHC Key Laboratory of Tropical Disease Control, School of Tropical Medicine and The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China.
Department of Clinical Laboratory, The Second Affiliated Hospital, Hainan Medical University, Haikou, China.
Infect Dis Poverty. 2022 Aug 4;11(1):87. doi: 10.1186/s40249-022-01012-9.
Burkholderia pseudomallei is a tropical pathogen that causes melioidosis. Its intrinsic drug-resistance is a leading cause of treatment failure, and the few available antibiotics require prolonged use to be effective. This study aimed to assess the clinical potential of B. pseudomallei phages isolated from Hainan, China.
Burkholderia pseudomallei strain (HNBP001) was used as the isolation host, and phages were recovered from domestic environmental sources, which were submitted to the host range determination, lytic property assays, and stability tests. The best candidate was examined via the transmission electron microscope for classification. With its genome sequenced and analyzed, its protective efficacy against B. pseudomallei infection in A549 cells and Caenorhabditis elegans was evaluated, in which cell viability and survival rates were compared using the one-way ANOVA method and the log-rank test.
A phage able to lyse 24/25 clinical isolates was recovered. It was classified in the Podoviridae family and was found to be amenable to propagation. Under the optimal multiplicity of infection (MOI) of 0.1, an eclipse period of around 20 min and a high titer (10 PFU/ml) produced within 1 h were demonstrated. This phage was found stabile at a wide range of temperatures (24, 37, 40, 50, and 60 °C) and pH values (3-12). After being designated as vB_BpP_HN01, it was fully sequenced, and the 71,398 bp linear genome, containing 93 open reading frames and a tRNA-Asn, displayed a low sequence similarity with known viruses. Additionally, protective effects of applications of vB_BpP_HN01 (MOI = 0.1 and MOI = 1) alone or in combination with antibiotics were found to improve viability of infected cells (70.6 ± 6.8%, 85.8 ± 5.7%, 91.9 ± 1.8%, and 96.8 ± 1.8%, respectively). A significantly reduced mortality (10%) and a decreased pathogen load were demonstrated in infected C. elegans following the addition of this phage.
As the first B. pseudomallei phage was isolated in Hainan, China, phage vB_BpP_HN01 was characterized by promising lytic property, stability, and efficiency of bacterial elimination during the in vitro/vivo experiments. Therefore, we can conclude that it is a potential alternative agent for combating melioidosis.
伯克霍尔德氏菌是一种热带病原体，可导致类鼻疽病。其内在的耐药性是治疗失败的主要原因，而少数可用的抗生素需要长期使用才能有效。本研究旨在评估从中国海南分离的伯克霍尔德氏菌噬菌体的临床潜力。
使用伯克霍尔德氏菌菌株（HNBP001）作为分离宿主，从国内环境来源中回收噬菌体，并进行宿主范围测定、裂解特性测定和稳定性测试。通过透射电子显微镜对最佳候选噬菌体进行分类。对其基因组进行测序和分析，评估其对 A549 细胞和秀丽隐杆线虫中伯克霍尔德氏菌感染的保护作用，使用单向方差分析方法和对数秩检验比较细胞存活率和存活率。
从 24/25 株临床分离株中回收了一种能够裂解的噬菌体。它被分类为 Podoviridae 家族，并且可繁殖。在最佳感染复数（MOI）为 0.1 的条件下，显示出约 20 分钟的潜伏期和在 1 小时内产生的高滴度（10 PFU/ml）。该噬菌体在广泛的温度（24、37、40、50 和 60°C）和 pH 值（3-12）下均稳定。被指定为 vB_BpP_HN01 后，对其进行了全序列测序，该线性基因组长 71398bp，包含 93 个开放阅读框和一个 tRNA-Asn，与已知病毒的序列相似性较低。此外，发现 vB_BpP_HN01（MOI=0.1 和 MOI=1）单独或与抗生素联合应用的保护作用可提高感染细胞的活力（分别为 70.6±6.8%、85.8±5.7%、91.9±1.8%和 96.8±1.8%）。在添加该噬菌体后，在感染秀丽隐杆线虫中观察到死亡率显著降低（10%）和病原体载量降低。
由于这是在中国海南分离的第一株伯克霍尔德氏菌噬菌体，噬菌体 vB_BpP_HN01 的体外/体内实验表现出有希望的裂解特性、稳定性和消除细菌的效率。因此，我们可以得出结论，它是一种有潜力的对抗类鼻疽病的替代药物。
