R-factor is an old name for a plasmid that codes for antibiotic resistance. Often, R-factors code for more than one antibiotic resistance factor: genes that encode resistance to unrelated antibiotics may be carried on a single R-factor. Many R-factors can pass from one bacterium to another through bacterial conjugation and are a common means by which antibiotic resistance spreads between bacterial species, genera and even families. For example RP1, a plasmid that encodes resistance to ampicillin, tetracycline and kanamycin originated in a species of Pseudomonas, from the Family Pseudomonadaceae, but can also be maintained in bacteria belonging to the family Enterobacteriaceae, such as Escherichia coli.
New technology: will it catch the "R" factor? Remote data transfer and other new technologies provide better ways to verify sales. Misreporting sales to customers is a longstanding and largely secretive practice.(Cover story)
Apr 01, 2007; Technology offers a bold new world for the vending industry. Two of the benefits that technology provides, improved...