摘要
      肠杆菌科中移动粘菌素抗性基因（mcr-1）的出现已成为全球公共卫生关注的问题。mcr-1基因可能通过与食物相关的细菌结合而传播。本研究调查了mcr-1基因在大肠杆菌中在液体培养基和绿豆芽生长过程中的转移频率。使用供体菌株大肠杆菌NCTC 13846（mcr-1阳性）和受体菌株大肠杆菌O157:H7和大肠杆菌O104:H4。体外交配实验在4、25和37°C下进行，持续时间长达36小时。在用供体和受体接种绿豆种子后的6天内，在芽生长室中以1分钟/小时的灌溉进行体内交配实验（生长芽）。大肠杆菌O104:H4和大肠杆菌O157:H7在TSB培养基中的最高转移频率分别为2.86E-07和3.24E-07，分别发生在交配24小时后的37°C。在4°C的液体培养基中未检测到转偶联物。此外，在绿豆芽生长期间，大肠杆菌O104:H4的mcr-1的转移频率（每个受体5.68E-05）比大肠杆菌O157:H7（每个受体1.02E-05）在第3天至第6天更高。这项研究表明，在绿豆芽生产过程中，细菌之间的抗生素抗性基因转移可能有助于抗生素抗性细菌在环境中和人类中的传播。
Abstract
The emergence of mobile colistin resistant gene (mcr-1) in Enterobacteriaceae has become a global public health concern. Dissemination of the mcr-1 gene through conjugation of bacteria associated with food may occur. This research investigated the transfer frequency of the mcr-1 gene among Escherichia coli in liquid media and during growth of mung bean sprouts. The donor strain E. coli NCTC 13846 (mcr-1 positive) and recipient strains of E. coli O157:H7 and E. coli O104:H4 were used. Mating experiments in vitro were conducted at 4, 25, and 37 °C for up to 36 h. The in vivo mating experiments (growing sprouts) were conducted in a sprout growth chamber with irrigation of 1 min/h over 6 days following inoculation of mung bean seeds with the donor and a recipient. The highest transfer frequencies in TSB media, 2.86E-07 and 3.24E-07, occurred at 37 °C after mating for 24 h for E. coli O104:H4 and E. coli O157:H7, respectively. Transconjugants were not detected in liquid media at 4 °C. Moreover, transfer frequency (5.68E-05 per recipient) of mcr-1 was greater during mung bean sprout growth for E. coli O104:H4 compared to E. coli O157:H7 (1.02E-05 per recipient) Day 3 to Day 6. This study indicates that the transfer of antibiotic resistant gene(s) among bacteria during mung bean sprout production may facilitate the spread of antibiotic resistant bacteria in the environment and to humans.

https://www.sciencedirect.com/science/article/abs/pii/S074000202200212X