Establishment and evaluation of standard strains of Burkholderia pseudomallei

Objective  According to the Technical Requirements for Evaluation of National Standard Strains of Pathogenic Microorganisms(WS/T 812—2022), construct a standard strain of Burkholderia pseudomallei.

Methods A systematic pathogenic study was conducted on ZH20BC01 through strain identification, morphological feature, motility characteristics, biochemical characteristics, antibiotic susceptibility. The passage stability of the ZH20BC01 were further determined by comparing and analyzing the differences in biochemical characteristics,susceptibility to antibiotics and genetic stability between G1, G5 and G10 strains.

Results  The results of colony morphology, Gram staining, Transmission Electron Microscope studies, Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) identification, 16S rDNA sequencing and biochemical testing demonstrate that the ZH20BC01 strain has typical characteristics of Burkholderia pseudomallei. Except for antibiotics such as amikacin and polymyxin B, ZH20BC01 showed a susceptible phenotype to most of the tested antibiotics. There is no significant difference in biochemical characteristics, antibiotic susceptibility and molecular genetic characteristics among the G1, G5, and G10 generations of ZH20BC01 bacteria, indicating good passage stability.

Conclusion A standard strain of Burkholderia pseudomallei was established and evaluated, which could be used in disease control,clinical diagnosis, teaching and scientific research and vaccine development in China.