Mlc (makes large colonies) from Escherichia coli is a transcriptional repressor which controls the expression of a number of genes encoding enzymes involved in glucose metabolism. Mlc forms stable homodimers in order to bind DNA, though it usually is found as a tetramer in studies using size exclusion chromatography. Hence, above a certain Mlc concentration, two homodimers can dimerize into a tetramer.

protein dimerization | homodimer | tetramer | MO-P-025