5.2.1.1 maleate isomerase - 5.2.1.10 2-Chloro-4-carboxymethylenebut-2-en-1,4-olide isomerase - 5.2.1.11 4-hydroxyphenylacetaldehyde-oxime isomerase deleted. The existence of this enzyme has been called into question by one of the authors of the reference previously cited. 5.2.1.12 zeta-carotene isomerase - 5.2.1.13 prolycopene isomerase - 5.2.1.14 beta-carotene isomerase - 5.2.1.2 maleylacetoacetate isomerase - 5.2.1.3 retinal isomerase deleted, now covered by EC 1.1.1.300, NADP-retinol dehydrogenase; EC 2.3.1.135, phosphatidylcholine—retinol O-acyltransferase; EC 3.1.1.64, retinoid isomerohydrolase; and EC 1.1.1.315, 11-cis-retinol dehydrogenase 5.2.1.4 maleylpyruvate isomerase - 5.2.1.5 linoleate isomerase - 5.2.1.6 furylfuramide isomerase - 5.2.1.7 retinol isomerase transferred to EC 3.1.1.64 5.2.1.8 peptidylprolyl isomerase - 5.2.1.9 farnesol 2-isomerase - 5.2.1.B4 2-methyl-cis-aconitate isomerase preliminary BRENDA-supplied EC number