FIGURE 2.

Overview of the general experimental approaches used to characterize an anti-infective candidate. A potential anti-infective compound that does not directly target bacterial growth can either impair pathogen virulence and/or enhance/modulate host immune responses. Various strategies from both pathogen and host perspectives can be employed to further characterize the molecular mechanism(s) of the compound of interest. Whole-genome transcriptome profiles of the compound-treated pathogen or host can be generated to study the effect of the compound. To assess the effect on bacterial virulence, qualitative and quantitative biochemical tests as well as biofilm production and quorum sensing assays can be performed. Bacterial mutants are useful for target identification while GFP-expressing bacteria may assist in visualization of in vivo bacterial colonization. Electron microscopy can be used to observe the formation of biofilm or bacterial structures (e.g., flagella). In silico molecular docking provides a clue of the possible binding interference between a bacterial protein and the compound of interest. From the host perspective, the live bacteria can be recovered from the C. elegans intestine and enumerated. The readily available transgenic mutant strains are useful for host target identification and pathway elucidation.