Figure 1

The two Xenopus histidine ammonia lyase (HAL) genes encode proteins highly homologous to mammalian HAL. Sequence alignment was carried out among the human (h), mouse (m) and the three HALs from Xenopus laevis (xl) and two HALs Xenopus tropicalis (xt), a diploid species. Note that the proteins are highly homologous throughout the entire length. The HAL1 and HAL2 from Xenopus laevis and Xenopus tropicalis shared about 84% identity between each other, similar to their homologies to the mammalian HAL.