image: Antibiotic resistance is becoming a huge medical challenge. Antibiotic resistance is caused by resistance genes carried on plasmids, small circles of DNA separate from the chromosomal DNA. Resistance spreads by horizontal gene transfer, in which plasmid genes from a donor bacterial cell spread to a recipient bacterial cell during cell-to-cell contact. When the DNA that is transferred includes antibiotic-resistance genes, the bacterium receiving this DNA becomes antibiotic-resistant too. This image relates to a paper that appeared in the Sept. 17, 2014, issue of Science Translational Medicine, published by AAAS. The paper, by Dr. S. Conlan at the National Human Genome Research Institute, NIH in Bethesda, Md., and colleagues was titled, 'Single-molecule sequencing to track plasmid diversity of hospital-associated carbapenemase-producing Enterobacteriaceae.' view more
Credit: C. Schaffer, <i>Science</i>/AAAS