Aminotransferase-like protein; part of the Fg3_54/C64 gene cluster that mediates the biosynthesis of the octapeptide fusaoctaxin A, a virulence factor that is required for cell-to-cell invasiveness of plant host (PubMed:30804501). The 2 nonribosomal peptide synthetases NRPS9 and NRPS5 form an assembly line which likely utilizes GABA as a starter unit (loaded on the unique module M1 of NRPS9) and sequentially incorporates seven extender units composed of the residues L-Ala, L-allo-Ile, L-Ser, L-Val, L-Ser, L-Leu and L-Leu, respectively (PubMed:30804501, PubMed:31100892). During the process, each of the residues that are tethered on modules M3-M7 of NRPS5 containing an E domain can undergo an epimerization reaction to produce a D-configuration before the transpeptidation reaction occurs (PubMed:30804501, PubMed:31100892). The elongation of the peptidyl chain might be terminated by module M8-mediated L-Leu incorporation, followed by R domain-catalyzed 4 electron reduction to release the resulting octapeptide from the assembly line as an alcohol (PubMed:30804501, PubMed:31100892). Fusaoctaxin A is cleaved by the cluster specific ABC transporter FGM5 to the pentapeptide fusapentaxin A and the tripeptide fusatrixin A (PubMed:31100892). The other enzymes from the cluster, FGM1, FGM2, FGM3 and FGM9 seem not to be involved in the biosynthesis of fusaoctaxin A and their functions have still to be determined (Probable). Expression is positively regulated by the cluster-specific transcription factor FGM4 and is induced during infection of coleoptiles of wheat seedlings (PubMed:23266949, PubMed:25333987). The fusaoctaxin A gene cluster is silenced by H3K27 trimethylation by the histone methyltransferase KMT6 (PubMed:31100892). Produces fewer spikelets with blight symptoms on susceptible wheat cultivars. Belongs to the class-V pyridoxal-phosphate-dependent aminotransferase family. Csd subfamily.