This entry contains bacterial 6-phosphogluconolactonases (6PGL)YbhE-type (EC:3.1.1.31) which hydrolyse 6-phosphogluconolactone to 6-phosphogluconate. The entry also contains the fungal muconate lactonising enzyme carboxy-cis,cis-muconate cyclase (EC:5.5.1.5) and muconate cycloisomerase (EC:5.5.1.1), which convert cis,cis-muconates to muconolactones and vice versa as part of the microbial beta-ketoadipate pathway. Structures of proteins in this family have revealed a 7-bladed beta-propeller fold [1].

1: The structure of Neurospora crassa 3-carboxy-cis,cis-muconate lactonizing enzyme, a beta propeller cycloisomerase. Kajander T, Merckel MC, Thompson A, Deacon AM, Mazur P, Kozarich JW, Goldman A; Structure. 2002;10:483-492. PMID:11937053