Anti‐infection drug testing model; L‐arginine, Part 2

This is part 2 of our study on the effects of L‐arginine on dissociating yeast ( Saccharomyces cerevisiae ) that are bound to Concanavalin A (ConA) derivatized agarose beads. In this study, concentrations of L‐arginine differ from part 1. Details of the method are presented in part 1. Here, in 126 total trials, 0M (control),0.05M 0.06M, 0.10M, 0.13M L‐arginine concentrations were tested for their effects on dissociating yeast bound to ConA derivatized agarose beads in distilled water over a 60 min time course. A two tailed t‐test showed that at all the L‐arginine concentrations tested yeast remaining bound to the ConA beads was significantly less that in control samples (no arginine) at p values ranging from less than 0.05 to less than 0.0001. While all L‐arginine concentrations significantly reduced yeast bound to the beads over control values, there was no statistically significant difference in the percentage of bound yeast between any of the 4 concentrations (p greater than 0.8). Mannose‐rich yeast binds to ConA (a mannose‐glucose binding lectin) and that forms the conceptual basis of this assay system. Here we show that an amino acid, L‐arginine, can interfere with the yeast‐ConA bead binding interaction. Yeast and lectin beads are a useful mimic for pathogens and human cells and therefore this simple, inexpensive assay system can be used to assay potential agents that might dissociate pathogens bound to human cells or prevent their binding in the first place (Supported by NIH NIGMS SCORE (S0648680), MARC, RISE, the Joseph Drown Foundation, and the Sidney Stern Memorial Trust).