The effect of wza gene deletion in Klebsiella pneumoniae on capsule formation and bacteriophage sensitivity
10.3760/cma.j.cn112150-20240226-00148
- VernacularTitle:肺炎克雷伯菌 wza基因缺失对荚膜形成与噬菌体敏感性的研究
- Author:
Zheng FAN
1
;
Hongbo LIU
;
Yuchen CHEN
;
Xiaohu CUI
;
Zhoufei LI
;
Tongtong FU
;
Jing YUAN
Author Information
1. 首都儿科研究所细菌学研究室，北京100020
- Keywords:
Klebsiella pneumoniae;
wza;
Gene knockout;
Capsule;
Bacteriophage
- From:
Chinese Journal of Preventive Medicine
2024;58(7):992-997
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effects of wza gene deletion in Klebsiella pneumoniae on capsule formation ability and bacteriophage sensitivity. Methods:The wza deletion mutant strain was constructed through a temperature-sensitive plasmid-mediated homologous recombination. The growth curves of W14 and Δ wza were detected by measuring the optical density OD 600. In order to analyze the effect of gene wza on bacterial capsule formation, wild-type strain W14 and Δ wza mutant strain were detected by transmission electron microscope, and their capsule contents were measured by quantifying the uronic acid contents. The plaque assay was used to detect bacterial sensitivity to bacteriophage in wild-type strain W14 and Δ wza mutant strain. The t test was used to compare whether there were differences in the contents of uronic acid in the capsules of wild-type strain W14 and Δ wza mutant strain. Results:The PCR results revealed that the Δ wza mutant strain was successfully constructed. Compared with wild-type strain W14, the growth curves of Δ wza on the solid plates demonstrated a slightly slower growth. However, no difference in growth was observed among wild-type strain W14 and Δ wza mutant strains in LB broth. The transmission electron microscope results showed that wza gene deletion resulted in the loss of capsule in bacteria. The uronic acid content assay suggested that the capsule content was significantly decreased in Δ wza mutant strain (45.963±2.795) μg/ml compared with wild-type strain W14 (138.800±5.201) μg/ml. There was a statistical difference between the two groups ( t=27.233, P<0.001). The plaque assay indicated that bacteria lost its sensitivity to bacteriophage when gene wza was deleted. Conclusion:Deletion of the wza gene impairs bacterial capsule formation ability and can affect bacterial sensitivity to bacteriophage phiW14.
