Transfection of clMagR/clCry4 imparts MR-T(2) imaging contrast properties to living organisms (E. coli) in the presence of Fe(3+) by endogenous formation of iron oxide nanoparticles

Rapid development of medical imaging, such as cellular tracking, has increased the demand for “live” contrast agents. This study provides the first experimental evidence demonstrating that transfection of the clMagR/clCry4 gene can impart magnetic resonance imaging (MRI) T(2)-contrast properties to living prokaryotic Escherichia coli (E. coli) in the presence of Fe(3+) through the endogenous formation of iron oxide nanoparticles. The transfected clMagR/clCry4 gene markedly promoted uptake of exogenous iron by E. coli, achieving an intracellular co-precipitation condition and formation of iron oxide nanoparticles. This study will stimulate further exploration of the biological applications of clMagR/clCry4 in imaging studies.