Glucosaminyl-6'-oxidase involved in the biosynthetic pathway of neomycin by mediating FAD-dependent dehydrogenation of paromamine to 6'-dehydro-6'-oxoparomamine. Works in combination with neamine transaminase to replace the 6-hydroxy group of paromamine with an amino group. Also able to collaborate with neomycin C transaminase to replace the 6'''-hydroxy group of 6'''-hydroxyneomycin C with an amino group. 6'''-deamino-6'''-hydroxyneomycin C + O2 = 6'''-deamino-6'''-oxoneomycin C + H2O2 O2 + paromamine = 6'-oxoparomamine + H2O2 Antibiotic biosynthesis; neomycin biosynthesis. Belongs to the GMC oxidoreductase family.