... isoforms of CytOX V [10,32]. The regulation of genes CytOX5a and CytOX5b, coding for the two isofoms Va and Vb, parallels that of genes CYC1 and CYC7, which encode iso-1 and iso-2 of yeast cytochrome ... 1). With the accompanying reduction in heme aa3levels, the enzyme activity per mg SMP protein indicates achange in the catalytic efficiency (TN) of the enzymecomplex in PC12 cells following ... coding for the subunits of CytOX, changes in the microenvironment of the cell may induce alterations in the catalytic efficiency of mammalian enzyme. Selective loss of CytOX subunits I/II and...