Legionella pneumophila is an intracellular pathogen causing pneumonia-like disease in humans. A 43-kb putative heavy metal efflux gene island was found on the L. pneumophila genome. Large Legionella deletion strains of the metal efflux genes were tested in human THP-1-derived macrophages and amoebal Acanthamoeba castellanii cells and were able to survive and replicate similar to the wild type, suggesting that they do not play a significant role within the intracellular environment. Examination of the sequence of this genomic island revealed that some genes were not accurately annotated and there were no known metal-responsive regulators encoded in this region. Therefore, functional roles of these metal resistance genes were tested by conducting metal resistance assays. Individual genes were cloned in an expression vector and expressed in an appropriate metal-sensitive Escherichia coli background with varying concentrations of the tested metal. Of the 11 efflux systems, a role was determined only for one. A Cu(I)-translocating P(IB)-type ATPase was shown to be encoded by lpg1024. This gene, termed copA, complemented a copper-sensitive (Delta copA) E. coli strain in trans and was able to confer copper resistance.

Minority group members’ participation in clinical research is essential for eliminating health disparities. Early recruitment procedures for a randomized control trial involving minority elders at local hospitals were unsuccessful, with challenges at hospital and individual levels. These challenges included referrals for home health care being written late during hospitalization, hospital staff reluctant to assist recruiters, ill minority elders and protective or unavailable caregivers. We met these challenges with evidence-based strategies, including changing inclusion criteria, increasing study staff, branding our study, using a consistently respectful manner, and pacing our process. After revising our approaches in various ways, we recruited close to our goal, with relatively good retention. Participants reported that benefiting the community rather than monetary reward was a strong motivator to join the study. Unexpected recruitment expenditures exceeded the recruitment budget. Our experiences include strategies that can be more cost-effective in future studies at both hospital and individual levels.

Aims:  The antibacterial efficacy of zeolites containing copper (Cu) or silver (Ag) ions or a combination was assessed against several reported copper‐resistant (CuR) bacterial strains. Methods and Results:  Comparison strains were obtained from the American Type Culture Collection that had no documented metal resistance. Reductions in bacterial populations were determined after exposure time intervals of 3, 6 and 24 h. All three CuR strains of Salmonella enterica exhibited resistance to Cu, Ag and Cu/Ag after three and 6 h of exposure. Both the CuR and comparison strain of Enterococcus faecium were resistant to both metals and the metal combination. CuRPseudomonas putida was significantly reduced by all zeolites within 3 h. The CuREscherichia coli strain was more sensitive to Cu, but more resistant to Ag than the comparison strain; however, significant reductions were achieved within 3 h with both Cu and Cu/Ag, and within 24 h with Ag. Conclusions:  Some strains with reported resistance to Cu were also resistant to Ag, suggestive of a shared resistance mechanism such as an indiscriminate Cu efflux pump. Ent. faecium appears to have innate resistance to both metals. In general, Ent. faecium was the most resistant species to the individual metals and the combination of metals, Ps. putida the least resistant, and the Salmonella strains were more resistant than E. coli. Significance and Impact of the Study:  Several of the comparison strains with no reported copper resistance were resistant to one or both metals. This may call into question the methods for determining bacterial metal resistance, which typically use nutrient‐rich media containing metals to assess the ability of the bacteria to grow in comparison with a wild‐type strain. Nevertheless, all the CuR strains evaluated in this study, with the exception of Ent. faecium, were reduced using the Cu and Ag zeolite combination.