Abstract

Titanium and its alloys are technically superior and cost-effective materials, with a wide variety of aerospace, industrial, marine, and commercial applications. In this study, the effects of titanium ions on bacterial growth were evaluated. Six strains of bacteria known to be resistant to both metal ions and antibiotics were used in this study. Two strains, Escherichia coli ATCC 15489, and Pseudomonas aeruginosa ATCC 10145, proved to be resistant to titanium ions. Plasmid-cured P. aeruginosa resulted in the loss of one or more resistance markers, indicating plasmid-encoded resistance. The plasmid profile of P. aeruginosa revealed the presence of a 23-kb plasmid. The plasmid was isolated and transformed into DH5α. Interestingly, the untransformed DH5α did not grow in 300 mg/l titanium ions, but the transformed DH5α grew quite well under such conditions. The survival rate of the transformed DH5α also increased more than 3-fold compared to that of untransformed DH5α.

• Keywords: titanium ion; resistance; Escherichia coli; Pseudomonas aeruginosa; bacteriostatic effect