This is the catalytic domain found in the endoplasmic reticulum (ER) -bound oxygenases mpaB' (MPAB2) and mpaB (MPAB) from Penicillium roqueforti and Penicillium brevicompactum and in the rubber oxygenase (Lcp) from Streptomyces sp., which contains highly conserved arginine and histidine residues. Structural analysis from Lcp revealed that Arg164, Thr168 and His198 are crucial active site residues [1]. The mpaB and mpaB' are part of the gene cluster that mediates the biosynthesis of mycophenolic acid (MPA) [2]. Lcp (Latex clearing proteins) is a rubber oxygenase that catalyses the extracellular cleavage of poly (cis-1,4-isoprene) [1,3]. This domain is also present in uncharacterised proteins from Mycobacterium sp. and hypothetical proteins, mainly from bacteria and fungi.

1: Structural and Functional Analysis of Latex Clearing Protein (Lcp) Provides Insight into the Enzymatic Cleavage of Rubber. Ilcu L, Rother W, Birke J, Brausemann A, Einsle O, Jendrossek D; Sci Rep. 2017;7:6179. PMID:28733658

2: Compartmentalized biosynthesis of mycophenolic acid. Zhang W, Du L, Qu Z, Zhang X, Li F, Li Z, Qi F, Wang X, Jiang Y, Men P, Sun J, Cao S, Geng C, Qi F, Wan X, Liu C, Li S; Proc Natl Acad Sci U S A. 2019;116:13305-13310. PMID:31209052

3: Latex Clearing Protein (Lcp) of Streptomyces sp. Strain K30 Is a b-Type Cytochrome and Differs from Rubber Oxygenase A (RoxA) in Its Biophysical Properties. Birke J, Rother W, Jendrossek D; Appl Environ Microbiol. 2015;81:3793-3799. PMID:25819959