Both enzymes
are isolated from the methylotrophic yeast Hansenula
polymorpa cells: the mutant C-105 (gcr1 catX) overproducing
AOX (Gonchar, Maidan, Pavlishko, & Sibirny, 2001) and the recombinant
strain Tf-11-6 overexpressing FLD1 gene coding for FdDH
(Demkiv et al., 2007).