Development of in vitro antimicrobial resistance in bacteria exposed to residue level exposures of antimicrobial drugs, pesticides and veterinary drugs.

Ten ppb or less of antibacterial drugs, pesticides and veterinary drugs could increase antibacterial resistance in bacteria. The minimum inhibitory concentration (MIC) was the indicator of resistance and Staphylococcus aureus ATCC 9144 the indicator organism. Seventeen compounds used in human, veterinary medicine, crop production, and found in the environment, were studied singly, and as combinations.

Novel reduction of mercury (II) by mercury-sensitive dissimilatory metal reducing bacteria.

The dissimilatory metal reducing bacterium (DMRB) Shewanella oneidensis MR-1 reduces ionic mercury (Hg[II]) to elemental mercury (Hg[0]) by an activity not related to the MerA mercuric reductase. In S. oneidensis, this activity is constitutive and effective at Hg(II) concentrations too low to induce mer operon functions.