Isolation, identification and biological characteristics analysis of a strain of Klebsiella pneumoniae

Abstract:

[Background] Klebsiella pneumoniae is a zoonotic opportunistic pathogen, which can cause infections in many animals and is difficult to be controlled. [Objective] To investigate the existence of pathogenic bacteria in a rhinoceros domestication farm. [Methods] Bacteria isolation and identification, drug resistance and drug resistance genes, virulence gene screening, and pathogenicity test in mice were performed on six samples of rhinoceros feces randomly collected. [Results] One Klebsiella pneumoniae strain was isolated, with the isolation rate of 16.67%. The isolate was resistant to six antibiotics, including doxycycline, polymyxin B and bacitracin, and carried six resistance genes and six virulence genes (kfuBC, fimH, ureA, uge, wabG, and wcaG). In the pathogenicity test, the strain suspension of 1×10¹⁰ CFU/mL led to a mortality rate as high as 80% in mice and lesions appeared in the liver, lung, and small intestine tissues of dead mice. [Conclusion] The K. pneumoniae strain isolated from the rhinoceros domestication farm had strong drug resistance, a low combination rate of drug resistance gene and drug resistance phenotype, and a complex drug resistance mechanism. The results of virulence gene prediction were in good agreement with the results of pathogenicity test. The data could provide reference for the prevention and control of K. pneumoniae infection in domestication farms.