Metals are among the most prevalent pollutants released into the environment. For these reasons, the use of biomarkers for environmental monitoring of individuals and populations exposed to metal pollution has gained considerable attention, offering fast and sensitive detection of chemical stress in organisms. There are different metal resistance genes in bacteria that can be used as biomarkers, including cation diffusion facilitators carrying metal ions; the prototype is the cobalt–zinc–cadmium transporter (czcD). The present study reports the expression changes in the czcD gene in Bacillus megaterium and Microbacterium liquefaciens under nickel and vanadium exposure by real‐time polymerase chain reaction. The nickel–vanadium‐resistant strains of B. megaterium and M. liquefaciens used in this study were isolated from mine tailings in Guanajuato, Mexico. The czcD gene showed high expression under exposure to 200 ppm of Ni and 200 ppm of V during the logarithmic growth phase of M. liquefaciens in PHGII liquid media. In contrast, no changes were observed in B. megaterium during logarithmic and stationary growth, perhaps due to the gene having differential expression during the growth phases. The expression profiles obtained for czcD show the possibility of using this gene from M. liquefaciens as a biomarker of nickel and vanadium pollution in microorganisms.

中文翻译：

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来自巨大芽孢杆菌和液化微杆菌的 czcD 基因作为潜在的镍钒土壤污染生物标志物

金属是释放到环境中最普遍的污染物之一。由于这些原因，使用生物标志物对暴露于金属污染的个人和人群进行环境监测已经引起了相当大的关注，它可以快速、灵敏地检测生物体中的化学应激。细菌中有不同的金属抗性基因可以作为生物标志物，包括携带金属离子的阳离子扩散促进剂；原型是钴-锌-镉转运蛋白（czcD）。本研究通过实时聚合酶链反应报道了镍和钒暴露下巨大芽孢杆菌和液化微杆菌中 czcD 基因的表达变化。本研究中使用的巨大芽孢杆菌和液化分枝杆菌的镍钒抗性菌株是从瓜纳华托的尾矿中分离出来的，墨西哥。在 PHGII 液体培养基中液化分枝杆菌的对数生长期暴露于 200 ppm Ni 和 200 ppm V 下，czcD 基因显示出高表达。相比之下，在对数生长和平稳生长期间，巨大芽孢杆菌中没有观察到变化，这可能是由于基因在生长阶段具有差异表达。获得的 czcD 表达谱显示了使用液化支原体的该基因作为微生物中镍和钒污染的生物标志物的可能性。可能是由于基因在生长阶段具有差异表达。获得的 czcD 表达谱显示了使用液化支原体的该基因作为微生物中镍和钒污染的生物标志物的可能性。可能是由于基因在生长阶段具有差异表达。获得的 czcD 表达谱显示了使用液化支原体的该基因作为微生物中镍和钒污染的生物标志物的可能性。