Five new type II manumycins (asukamycins A-II, B-II, C-II, D-II, E-II) containing a hydroxyquinol mC7N unit were discovered in cultures of Streptomyces nodosus ssp. asukaensis. Their structures were elucidated using NMR, LC-MS, LC-MS/MS, and HR-MS, showing they correspond to type I manumycin counterparts with an epoxyquinol mC7N unit. The biosynthetic origin of type II manumycins from type I compounds was confirmed by time-course production analysis and the incorporation of [7'-13C]asukamycin A into asukamycin A-II. Substrate preference studies supported an enzyme-mediated conversion, with a slight preference for branched 'upper' chain termini in type I substrates. These results demonstrate type II manumycins are derived from type I congeners, clarifying their biogenesis.