LAUSR

Abstract Coaggregation, the specific recognition and adhesion of genetically distinct bacteria, is proposed to contribute to the development of freshwater biofilms. This work aimed to develop a microplate-based system to measure and model the kinetics of freshwater bacterial coaggregation. Blastomonas natatoria 2.1 and Micrococcus luteus 2.13 were evaluated for coaggregation ability using 24-well microplates containing novel dome shaped wells (DSWs) and standard flat-bottom wells. Results were compared to a tube-based visual aggregation assay. The DSWs facilitated the reproducible detection of coaggregation via spectrophotometry and the estimation of coaggregation kinetics using a linked mathematical model. Quantitative analysis using DSWs was more sensitive than the visual tube aggregation assay and subject to substantially less variation than flat-bottom wells. Collectively these results demonstrate the utility of the DSW-based method and improve upon the current toolkit for studying freshwater bacterial coaggregation.