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SummaryMicroarray technology is currently used in the development of carbohydrate drugs and diagnostic tests. Here we model an inexpensive alternative to microarrays using derivatized microbeads. In this model we examine the binding of mannose-rich yeast to microbeads derivatized with concanavalin A (Con A), a mannose-binding lectin, in the presence of 30 different sugars and 9 different pH conditions. We developed a listing of effective saccharide inhibitors of immobilized Con A based on 3901 replicates. We suggest that this is the most extensive saccharide inhibitor list ever developed for this lectin and it may be useful to use this listing to replace the less extensive lists that have been in the literature for decades. Information is also provided on pH effects on immobilized Con A binding based on 918 trials. Two assays to study binding, one which qualitatively scores more or less binding than control in thousands of replicate samples, and another that quantitatively evaluates binding by counting the number of cells bound to each bead, are also modeled here. We know of no previous studies that provide such as extensive information on saccharide inhibition and pH effects on the binding of immobilized Con A. We suggest that this microbead approach, using beads derivatized with lectins or sugars, and the two simple assays presented here, can in some cases, substitute for more expensive microarray technology in the development of carbohydrate drugs and diagnostic tests. If, for example, our model Saccharomyces cerevisiae was a pathogen, these studies show that it binds via cell surface mannose residues and drugs to prevent binding could be developed using the inhibitors of binding identified here. The beads could be also used in the development of diagnostic tests that identify the presence of the organism in blood samples, etc. in much the same way as microarray technology is being used today.

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We are identifying reagents that unclump cells in a model yeast system (Saccharomyces cerevisiae) for potential uses in clinical and other applications. Here 7 salts (0.1M concentration range) and no salt controls were stirred with fixed yeast at 20 min intervals over a 60 min time course in 1 ml distilled water droplets on glass microscope slides in 2545 trials by 45 independent investigators counting percentages of unclumped yeast vs clumps at each time point. The 7 salts were chosen because of their relationship to a known anti‐clumping agent magnesium sulfate. The following hierarchy of best to worst unclumping (compared with controls) was established at the 60 min time. Average percent single cells vs controls of all the trials appears in parentheses: sodium sulfate (+20.0), magnesium sulfate (+17.6), potassium sulfate (+9.9), magnesium carbonate (‐1.6), magnesium chloride (‐7.3), calcium carbonate (‐8.4), calcium sulfate (‐13.0). Individual groups of values varied from +59% to ‐41%. T tests were performed to compare results of experimentals vs controls. These results might help identify reagents that can be useful in unclumping cells in the bloodstream such as in anti‐thrombocytic and anti‐cancer applications, in reducing infectivity and biofilm development as well as in industrial applications (support: Sidney Stern Memorial Trust, NIH RISE, NSF Presidential Award 0731633 and Cal State).