Protein
Lactamase-like protein nscB
Organism
Arthroderma otae (strain ATCC MYA-4605 / CBS 113480)
Function
Lactamase-like protein; part of the gene cluster that mediates the biosynthesis of neosartoricin B, a prenylated anthracenone that probably exhibits T-cell antiproliferative activity, suggestive of a physiological role as an immunosuppressive agent (PubMed:23758576, PubMed:23368997). The non-reducing polyketide synthase nscA probably synthesizes and cyclizes the decaketide backbone (By similarity). The hydrolase nscB then mediates the product release through hydrolysis followed by spontaneous decarboxylation (By similarity). The prenyltransferase nscD catalyzes the addition of the dimethylallyl group to the aromatic C5 (By similarity). The FAD-dependent monooxygenase nscC is then responsible for the stereospecific hydroxylation at C2 (By similarity). Neosartoricin B can be converted into two additional compounds neosartoricins C and D (By similarity). Neosartoricin C is a spirocyclic compound that is cyclized through the attack of C3 hydroxyl on C14, followed by dehydration (By similarity). On the other hand, neosartoricin D is a further cyclized compound in which attack of C2 on C14 in neosartoricin C results in the formation of the acetal-containing dioxabicyclo-octanone ring (By similarity). Both of these compounds are novel and possibly represent related metabolites of the gene cluster (By similarity).
Similarity
Belongs to the metallo-beta-lactamase superfamily.
Sequence
MGGRMPFNQSFWEEFLMGREGRLPTLPEISHVSKRVVRILGGNPGSMHLQGTNTYLVGTGRSRILIDTAQVKQASFLRLQRAPSQLIHSKKGLPVWISRISSFLRTHNLELSYVLLTHWHGDHTGGVPDLLAHSPSLADKIYKNCPDAGQNPITDGQIFSVNGATVRAVFTPGHSVDHMCFQLEEENALFTGDNVLGHGFSVAQDLGRYMHSLGDMASLGCGIGYPAHGAVIGNLPEKLEEYMKHREGRERMMLSTLTREQAQGEGGRVGETKGGLTLNEIVIAMYGRVPQEVVEKALAPSLLQVLWKLAEDRRVGFKPGDPLKRRWFALDQRKRNRVRGYPS