The role of lysine 55 in determining the specificity of the purine repressor for its operators through minor groove interactions. Glasfeld A, Koehler AN, Schumacher MA, Brennan RG. The role of lysine 55 in determining the specificity of the purine repressor for its operators through minor groove interactions. J Mol Biol. 1999;291(2):347-61. doi:10.1006/jmbi.1999.2946 Read more