离子环境对Acinetobacter sp. ADP1的salR基因活性的影响

Influence of Ions Conditions on salR Gene in Acinetobacter sp. ADP1

革兰氏阴性菌Acinetobacter sp. ADP1可以利用水杨酸作为惟一的碳源和能源生长,与这一代谢过程相关的基因为sal基因。利用sal基因启动子与细菌荧光素酶基因(lux)编码区融合而构建的工程菌Acinetobacter ADPWH_lux,通过定量测定活细胞发光度可以检测出salR基因在不同离子环境中的活性。本试验测定了不同浓度梯度的10种金属离子对处于指数期和稳定期的细菌的salR基因活性的影响。发光度检测表明重金属离子均会抑制指数期和稳定期的细菌的发光能力。RT-PCR试验也证明,凡能够抑制细菌发光能力的离子,均会抑制细菌的salA基因的转录。

Acinetobacter sp. ADP1, a gram-negative bacterium, can utilize salicylate as the unique carbon source and energy source, and sal operon is required for the metabolism. Genetically engineered Acinetobacter ADPWH_lux containing fusion gene combined with full salA gene and promoter less luxCDABE gene, was used for live-cell based quantitatively bioluminescence assay to determine the SalR activities in different ions conditions. The influence of 10 kinds of cations in different concentrations on salR in Acinetobacter sp. ADP1 in the exponential and stationary phases was determined. The biolumincscence assay illuminated most of heavy metal ions inhibit the bioluminescence abilities of the bacterium in both exponential and stationary phases. The corresponding RT-PCR experiments also proved that all the ions which inhibit the bioluminescence abilities, can also inhibit the transcription of salA gene.