The pathogenicity of or aerobactin-positive in infected mice.

OBJECTIVES

To investigate the pathogenicity of (KPN) possessing or the aerobactin gene in infected mice.

METHODS

BALB/c mice were divided into four groups (n = 10 per group) and infected with: string test-positive and -positive or aerobactin-positive KPN (group 1), string test-negative but -positive KPN (group 2), string test-negative but aerobactin-positive KPN (group 3), or string test- and /aerobactin-negative KPN (group 4). Mouse survival time was compared among groups, and the infection of livers, spleens, lungs, and kidneys and KPN growth were assessed in infected mice.

RESULTS

Compared with the negative group (group 4), the survival rates of mice infected with - or aerobactin-positive KPN (groups 1–3) were significantly lower, their multi-organ injuries were significantly more severe, and bacterial enumeration was significantly higher.

CONCLUSIONS

Despite being string test-negative, aerobactin- or -positive KPN still exhibit high virulence and anti-immune effect activity. Therefore, the combination of the string test and gene detection of aerobactin and will be helpful in screening hypervirulent KPN.