RecA is a DNA repair protein found in Escherichia coli, with homologues found in mammalian species. RecA is a DNA dependent ATPase that hydrolyzes ATP in the presence of single or double-stranded DNA. RecA has pH dependent affinities for ssDNA and dsDNA binding and ATP hydrolysis. Previous studies in our laboratory have shown that a variety of salts, substrates and pH conditions alter RecA structure and stability. In this study, three buffers were used to study the thermal unfolding and ATPase activity of RecA. RecA unfolding in HEPES, MES, and potassium phosphate buffers is compared to unfolding in Tris buffer at a variety of pH levels (6.5, 7.0, 7.5, 8.0, 8.5). Circular Dichroism was used to follow the unfolding transitions and to determine the melting temperature of RecA at each given pH in each of the various buffers. Activity assays were conducted for each of the solution conditions used for the CD studies in order to study how buffer composition and pH influences RecA activity. Differences in melting temperatures between buffers at a given pH suggest that the buffer itself may alter the aggregation state and stability of RecA.