纳米氧化铝对多重耐药质粒RP4接合转移的影响

Mechanism of Al2O3 Nanoparticle Influence on RP4-mediated Conjugation a Preliminary Research in Bacterium Morphology

接合供体菌为大肠杆菌HB101（RP4）,受体菌为Salmonella aberdeen Kauffmann50312（str^R）,供、受体菌液均为10^9cfu/mL（浓度比为1：3）,25℃静止接合8h后计算接合子,采用透射电镜和激光扫描共聚焦显微镜进行形态学研究,结果表明,RP4的接合转移随着纳米Al2O3浓度的升高具有上升趋势,5mmol/L和50mmol/L纳米Al2O3组接合率分别为空白对照组的150倍和40倍,具有非常显著的差异,说明,纳米Al2O3能够促进接合子的产生,其影响机理可能是因为纳米Al2O3能够改变细胞膜通透性,间接影响接合过程,或者直接促进接合基因的表达所致。

Mating was conducted between E.coli HBIOI（RP4） and Salmonella aberdeen Kauffmann 50312（str^R） in saline at 25℃ without stirring for 8h. The starting concentration of donor and recipient were both about 10^9 cfu/mL （donor per recipient ratio was 1 ： 3）.Later transmission electron microscope （TEM） and laser scan confocal microscope （LSCM） were employed to investigate cell morphology and structure. The research show that 5mmol/L and 50mmol/L Al2O3 nanoparticle could increase the conjugal transfer frequency by 150-fold and 40-fold respectively and interpreted that Al2O3 nanopartiele can stimulate RP4 conjugal transfer. Conjugative gene is highly regulated. Al2O3 nanopartiele might modulate con- jugative gene expression directly or influence cell membrane permeability and thus modulate the process of conjugation indirectly.