An outbreak of Salmonellosis erupted in Ohio, Michigan, Georgia, and Alabama during the winter of 1981. Frustrated epidemiologists could find no common link, until they finally realized what all the victims had in common: marijuana.1 Samples of pot used by some patients in Michigan were tainted with Salmonella muenchen, which was phenotypically unremarkable, except for the presence of two low-molecular-weight plasmids. Genetic fingerprinting of these non-chromosomal DNAs tied the cases together, and even uncovered new incidents that investigators did not know were linked to the outbreak.
Twenty years later, this marriage of molecular biology and microbiology continues to evolve, as have the tools of the trade. In today's microbiology laboratory, loops and Bunsen burners share bench space with real-time PCR machines, automated DNA sequencers, and microarray readers. Every branch of the field has benefited. Vigilant microbiologists and epidemiologists are spotting disease outbreaks earlier, and microbial ecologists seeking novel microbes in ...
