Sampling bias created by ampicillin in isolation media for Aeromonas

Jennifer R. Huddleston, John Zak, Randall Jeter

Research output: Contribution to journalArticlepeer-review


Members of the bacterial genus Aeromonas are widely isolated from aquatic environments and studied in part for their ability to act as opportunistic pathogens in a variety of animals. All aeromonads, with the exception of Aeromonas trota, are generally thought to be resistant to ampicillin, so the antibiotic is frequently added to isolation medium as a selective agent. In this study, 282 aeromonads from environmental sources were isolated on a medium without ampicillin and their resistance to ampicillin determined. Of the 104 of these isolates that were judged to be independent (nonredundant), 18 (17.3%) were susceptible to ampicillin. A chi-square analysis was performed to determine the impact of ampicillin use on enumerating Aeromonas species from environmental samples. Our results indicate that, when ampicillin is used as a selective agent, a significant portion of the aeromonad population in at least some environments can be omitted from isolation.
Original languageEnglish
Pages (from-to)39–44
JournalCanadian Journal of Microbiology
StatePublished - Feb 7 2007


Dive into the research topics of 'Sampling bias created by ampicillin in isolation media for Aeromonas'. Together they form a unique fingerprint.

Cite this