Presence and turnover of adenosine diphosphate ribose in human erythrocytes.
ADP-ribose was detected in human red blood cells (RBC) at 0.45 +/- 0.1 microM concentrations. These levels could be estimated after purification of ADP-ribose by means of three sequential HPLC fractionations of RBC extracts. Extraction was performed by sonication of RBC either in trichloroacetic acid, followed by centrifugation, or in carbonate-bicarbonate buffer, pH 10.0, followed by rapid ultrafiltration. Neither procedure of extraction caused artefactual formation of ADP-ribose. Prolonged incubation of intact RBC in isotonic buffer containing labeled orthophosphate resulted in the slow incorporation of radioactivity into ADP-ribose. Identification of the labeled ADP-ribose was confirmed upon incubation of the purified metabolite with nucleotide pyrophosphatase, yielding radioactive 5'-AMP and ribose 5-phosphate, while its exposure to a nonspecific deaminase resulted in the quantitative formation of labeled inosine diphosphate ribose.
Guida
L
L
Institute of Biochemistry, University of Genoa, Italy.
Zocchi
E
E
Franco
L
L
Benatti
U
U
De Flora
A
A
D000244:Adenosine Diphosphate / Q000097:blood; D000246:Adenosine Diphosphate Ribose / Q000097:blood* / Q000302:isolation & purification; D000255:Adenosine Triphosphate / Q000097:blood; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000737:chemistry / Q000378:metabolism*; D006454:Hemoglobins / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D009243:NAD / Q000097:blood*; D010710:Phosphates / Q000097:blood; D010761:Phosphorus Radioisotopes; D011865:Radioisotope Dilution Technique
D002250:Carbon Radioisotopes; D006454:Hemoglobins; D010710:Phosphates; D010761:Phosphorus Radioisotopes; D009243:NAD; D000246:Adenosine Diphosphate Ribose; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate