Mechanism and stereochemistry of the 5-aminolaevulinate synthetase reaction.
1. Two mechanisms for the biosynthesis of 5-aminolaevulinate from glycine and succinyl-CoA (3-carboxypropionyl-CoA) are considered. One of the mechanisms involves the retention of both the C-2 H atoms of glycine during the synthesis of 5-aminolaevulinate, whereas the other predicts the retention of only one of the C-2 H atoms of glycine. 2. Highly purified 5-aminolaevulinate synthetase from Rhodopseudomonas spheroides was used to show that the C-2 H atom of glycine with R configuration is specifically removed during the biosynthesis of 5-aminolaevulinate. 3. The mechanism of the condensation therefore differs from the analogous reaction of the biosynthesis of sphinganine from palmitoyl-CoA and serine, in which the C-2 H of serine is retained (Wiess, 1963).
D000624:5-Aminolevulinate Synthetase; D002250:Carbon Radioisotopes; D002498:Centrifugation; D005998:Glycine / Q000378:metabolism; D007700:Kinetics; D007982:Levulinic Acids / Q000096:biosynthesis; D008956:Models, Chemical; D012242:Rhodobacter sphaeroides / Q000201:enzymology; D013329:Structure-Activity Relationship; D014316:Tritium
D002250:Carbon Radioisotopes; D007982:Levulinic Acids; D014316:Tritium; D000624:5-Aminolevulinate Synthetase; D005998:Glycine