This domain is found in a group of proteins from proteobacteria and fungi, including the bifunctional enzyme Oxalate biosynthetic component 1 from Burkholderia pseudomallei (Obc1, Swiss:Q63KK6). This entry represents the cap domain of Obc1, which adopts an alpha- helical fold, with two layers of anti-parallel helices [1].

1: Structural Insights into an Oxalate-producing Serine Hydrolase with an Unusual Oxyanion Hole and Additional Lyase Activity. Oh J, Hwang I, Rhee S; J Biol Chem. 2016;291:15185-15195. PMID:27226606