Among these five heavy metals,
the influences of Hg2+ and Zn2+ on the antibiotic resistance of Pseudomonas putida XX6
were the most significant,
as the addition of Hg2+ made the bacterial resistance to norfloxacin decrease rapidly,
and the inoculant failed to grow up on the media with 0.01 mg/mL Hg2+ and the norfloxacin disc.