Involved in the modification of the terminal sugar residues in the last two steps in the biosynthesis of polyketide antibiotics of the aclacinomycin group. In the first reaction, it catalyzes the oxidation of the hydroxyl group at carbon C4 of the L-rhodinose terminal sugar moiety of aclacinomycin N (AclN) to a keto group, modifying the sugar to cinerulose A and generating aclacinomycin A (AclA). In the second reaction, it catalyzes the elimination of two hydrogen atoms from cinerulose A, leading to a double bond between carbon atoms C2 and C3 and the generation of the L-aculose terminal sugar moiety of aclacinomycin Y (AclY). It can also use aclacinomycin analogs, epsilon-pyrromycinone glycosides, rhodirubins (A, B, C and E) and all triglycosides containing L-cinerulose, L-rhodinose or 2-deoxy-L-fucose as terminal sugar. aclacinomycin N + O2 = aclacinomycin A + H2O2 aclacinomycin A + O2 = aclacinomycin Y + H2O2 Binds 1 FAD per subunit in a bicovalent manner. Inhibited by ascorbic acid and iron ion. kcat is 0.17 sec(-1) for oxidase activity with AclA. Optimum pH is 5.5. Homotetramer; dimer of dimers. Predicted to be exported by the Tat system. The position of the signal peptide cleavage has been experimentally proven. The FAD cofactor is bound via a bicovalent 6-S-cysteinyl, 8alpha-N1-histidyl FAD linkage. Cells lacking this gene accumulate various aclacinomycin analogs. AknOx uses two distinct sets of catalytic residues in the two reactions. Tyr-493 is responsible for proton abstraction from the C-4 hydroxyl group in the first reaction, the oxidation of rhodinose to cinerulose A. Tyr-421 is responsible for the proton abstraction from C3 of cinerulose A in the second reaction, for formation L-aculose. Belongs to the oxygen-dependent FAD-linked oxidoreductase family.