Involved in the naphthalene catabolic pathway. Catalyzes the reversible glutathione-dependent isomerization of 2-hydroxychromene-2-carboxylate (HCCA) to trans-O-hydroxybenzylidenepyruvate (THBPA). 2-hydroxychromene-2-carboxylate = (3E)-4-(2-hydroxyphenyl)-2-oxobut-3-enoate Glutathione seems to stabilize the enzyme, which loses activity rapidly in the absence of this compound. kcat is 47 sec(-1) for HCCA, 19 sec(-1) for THBPA and 39 sec(-1) for glutathion. Optimum pH is 10. Aromatic compound metabolism; naphthalene degradation. Belongs to the GST superfamily. NadH family.