2'-Deoxyadenosine metabolism in human and opossum Didelphis virginiana erythrocytes in vitro.
1. In erythrocytes of both species, deamination and phosphorylation of dADO was completely inhibited by 5 microM 2'deoxycoformycin and 10 microM 5-ITU respectively. 2. Under physiologic conditions, provided with nanomolar concentrations of dADO there was complete deamination of dADO in human red cells. In opossum erythrocytes deamination and phosphorylation of the deoxynucleoside were nearly; additionally, 1-2% of the substrate was metabolized to AXP. 3. With ADA inhibited in intact red cells, apparent Km and Vmax for dADO were 0.5 vs 0.1 mM and 0.8 vs 6.25 mumol/g hg/hr in human and opossum cells, respectively. 4. In opossum red cell lysates, GTP was superior to ATP and to dATP as a phosphate donor in the dADO kinase reaction.
Bethlenfalvay
N C
NC
Department of Primary Care, Fitzimons Army Medical Center, Aurora, CO 80045.
Lima
J E
JE
Banks
R E
RE
D000818:Animals; D003839:Deoxyadenosines / Q000097:blood*; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000502:physiology; D009893:Opossums / Q000097:blood*; D010766:Phosphorylation; D011092:Polyethylene Glycols / Q000494:pharmacology*
D003839:Deoxyadenosines; D011092:Polyethylene Glycols; D008274:Magnesium; C058118:2'-deoxyadenosine