耐药性副溶血性弧菌生长异质性比较研究

Comparative study on growth heterogeneity of antimicrobial resistant Vibrio parahaemolyticus

目的在不同温度(10、20、30、37℃)下,比较17株不同耐药性、耐药表型及基因型不一致的副溶血性弧菌在碱性蛋白胨水(3%NaCl)中最大比生长速率及生长快慢之间的差异。方法应用Bioscreen C全自动微生物生长曲线分析仪测定副溶血性弧菌的最大比生长速率,构建不同温度下生长曲线,采用修正后的Gompertz模型进行拟合得出生长动力学参数。结果不同耐药性副溶血性弧菌μmax存在一定差异,差异随着温度的降低而增加,抗生素耐药种类越多,其μmax越大;同一温度下,耐药表型与基因型不一致的副溶血性弧菌其生长参数存在一定的差异,但是菌株的生长参数的差异与菌株耐药表型与基因型不一致之间没有明显的对应关系。结论菌株之间的微生物生长动力学参数的异质性将会对风险评估的准确性带来影响,此结果可为多重耐药副溶血性弧菌风险评估提供基础数据支持。

Objective To compare the maximal specific growth rate and growth rate of 17 strains of Vibrio parahaemolyticus with different drug resistance, drug-resistant phenotype and genotype incongruent in alkaline peptone water（APW, 3%NaCl） at different temperatures（10, 20, 30, 37 ℃）. Methods The maximum specific growth rate of Vibrio parahaemolyticus was determined by Bioscreen C automatic microorganism growth curve analyzer. The growth curves of different temperatures were constructed and the growth kinetic parameters were obtained by using the modified Gompertz model. Results There was a certain difference between different drug resistant Vibrio parahaemolyticus, and the difference increased with the decrease of temperature. The more variety of antibiotic resistance, the bigger the μmax was. At the same temperature, there was a certain difference in the growth parameters between the resistant phenotype and the genotype incongruent Vibrio parahaemolyticus. However, there was no significant correlation between the growth parameters of the strains and the inconsistency of the resistant phenotype and genotype of the strain. Conclusion The heterogeneity of microbial growth kinetics parameters between strains will affect the accuracy of risk assessment. This result can provide basic data support for the risk assessment of multi-drug resistant Vibrio parahaemolyticus.