Hardy et al. Clinically Isolated Bacteria Inhibit S. aureus Galleria mellonella caterpillars. While future studies will seek to define the molecular mechanisms of the inhibitory activities, our current findings support the study of polymicrobial interactions as a strategy to understand bacterial competition and to identify novel therapeutics against S. aureus and other pathogens.

Although the available anti-HIV drugs can, in combination, block viral replication, current therapies do not eliminate the viral infection. As a consequence, patients are currently prescribed multiple drugs (usually three). This approach is called combination antiretroviral therapy (cART). cART is the standard of care because treating patients with monotherapies fails to completely suppress HIV-1 replication, which leads to the rapid emergence of drug resistance (Havlir, McLaughlin, & Richman, 1995; Shafer et al., 2003). In most patients who are compliant, there is a decrease, over several months, in the level of viral RNA in the blood to levels below what can be detected in standard commercial assays (Maldarelli et al., 2007; Perelson et al., 1997). The most effective anti-HIV therapies target the HIV-1 viral enzymes protease, reverse transcriptase (RT), and integrase. The current standard of care for treatment-naïve patients includes an integrase strand transfer inhibitor (INSTI) plus two additional nucleoside reverse transcriptase inhibitors

The microbiome is essential for host health, and perturbations resulting from antibiotic use can lead to dysbiosis and disease. Diet can be a powerful modulator of microbiome composition and function, with the potential to mitigate the negative effects of antibiotic use. Thus, it is necessary to study the impacts of diet and drug interactions on the gut microbiome. Coffee is a commonly consumed beverage containing many compounds that have the potential to affect the microbiome, including caffeine, polyphenols, and fiber. We supplemented mice with caffeinated and decaffeinated coffee in conjunction with amoxicillin, and used 16S rRNA amplicon sequencing of fecal samples to investigate changes in diversity and composition of the murine fecal microbiome. We found that antibiotics, regardless of coffee supplementation, caused significant disruption to the murine fecal microbiome, enriching for Proteobacteria, Verrucomicrobia, and Bacteroidetes, but reducing Firmicutes. While we found that coffee alone did not have a significant impact on the composition of the fecal microbiome, coffee supplementation did significantly affect relative abundance metrics in mice treated with amoxicillin. After caffeinated coffee supplementation, mice treated with amoxicillin showed a smaller increase in Proteobacteria, specifically of the family Burkholderiaceae. Correspondingly we found that in vitro, Burkholderia cepacia was highly resistant to amoxicillin, and that it was inhibited by concentrations of caffeine and caffeinated coffee comparable to levels of caffeine in murine ceca. Overall, this work shows that coffee, and possibly the caffeine component, can impact both the microbiome and microbiome members during antibiotic exposure.