Lyase class I_like superfamily: contains the lyase class I family, histidine ammonia-lyase and phenylalanine ammonia-lyase, which catalyze similar beta-elimination reactions
Lyase class I_like superfamily of enzymes that catalyze beta-elimination reactions and are active as homotetramers. The four active sites of the homotetrameric enzyme are each formed by residues from three different subunits. This superfamily contains the lyase class I family, histidine ammonia-lyase and phenylalanine ammonia-lyase. The lyase class I family comprises proteins similar to class II fumarase, aspartase, adenylosuccinate lyase, argininosuccinate lyase, and 3-carboxy-cis, cis-muconate lactonizing enzyme which, for the most part catalyze similar beta-elimination reactions in which a C-N or C-O bond is cleaved with the release of fumarate as one of the products. Histidine or phenylalanine ammonia-lyase catalyze a beta-elimination of ammonia from histidine and phenylalanine, respectively.