N-malonyltransferase FDB2

UniProtKB accession:  W7NDP8

Grouped By:  Matching UniProtKB accession

UniProtKB description:  N-malonyltransferase; part of the Fusarium detoxification of benzoxazolinone cluster 2 (FDB2) involved in the degradation of benzoxazolinones produced by the host plant (PubMed:19302487, PubMed:26808652). Maize, wheat, and rye produce the 2 benzoxazinone phytoanticipins 2,4-dihy-droxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) that, due to their inherent instability once released, spontaneously degrade to the more stable corresponding benzoxazolinones, 6-methoxy-2-benzoxazolinone (MBOA) and 2-benzoxazolinone (BOA), respectively (PubMed:11876429). The first step in the detoxification of benzoxazolinones involves the hydrolysis of the cyclic ester bond of benzoxazolinones by the FDB1 cluster gamma-lactamase MBL1 to aminophenols (PubMed:26808652, PubMed:12788712). MBL1 is able to convert BOA into 2-aminophenol (2-AP), as well as MBOA into 5-methoxy-2-aminophenol (2-AMP) (PubMed:26808652, PubMed:12788712). The FDB2 cluster N-malonyltransferase FDB2/NAT1 then metabolizes aminophenols via N-malonylation to non-toxic malonamic acids (PubMed:19302487, PubMed:12788712). FDB2/NAT1 converts 2-AP into N-(2-hydroxyphenyl) malonamic acid (HPMA) and 2-AMP into N-(2-hydroxy-4-methoxyphenyl) malonamic acid (HMPMA) (PubMed:19302487, PubMed:12788712). The duplicated dienlactone hydrolases DLH1 and DLH2 may provide redundant function for hydrolyzing the lactone moiety in the BOA molecule (Probable). The roles of the amidases an other enzymes encoded by the 2 FDB clusters have not been identified so far (Probable).