Properties of the 3'-phosphoadenosine-5'-phosphosulfate (PAPS) synthesizing systems of brain and liver.
Chromatography of brain and liver 100,000 g supernatants over HPLC molecular sieve columns revealed striking differences in the molecular weight distribution of ATP-sulfurylase and APS-kinase of the two tissues, pointing to different enzymic species for both enzymes in brain and liver. This was further substantiated by kinetic characterization of the two enzymes of both tissues. APS-kinase of liver is allosterically activated by ATP, while the brain enzyme is not. ATP-sulfurylase of brain is activated at high, but still physiological concentrations of ATP. Brain ATP-sulfurylase is inhibited by phenylalanine.
D000227:Adenine Nucleotides / Q000096:biosynthesis*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D004789:Enzyme Activation; D007527:Isoenzymes / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008970:Molecular Weight; D009713:Nucleotidyltransferases / Q000378:metabolism*; D010724:Phosphoadenosine Phosphosulfate / Q000096:biosynthesis*; D010770:Phosphotransferases / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor); D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013430:Sulfate Adenylyltransferase / Q000378:metabolism*
D000227:Adenine Nucleotides; D007527:Isoenzymes; D010724:Phosphoadenosine Phosphosulfate; D000255:Adenosine Triphosphate; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C019617:adenylylsulfate kinase; D009713:Nucleotidyltransferases; D013430:Sulfate Adenylyltransferase