Porphyrin biosynthesis. Immobilized enzymes. IV. Studies on aminolaevulate dehydratase attached to Sepharose.
Bovine liver aminolaevulate dehydratase (ALA-D) has been chemically attached to Sepharose 4B and its properties have been studied. The optimal conditions for coupling have been determined. It was found that the immobilized enzyme retained a significant percentage of the activity of the free enzyme. The coupling yield was rather high. The insolubilized enzyme requires both anaerobiosis and a thiol activator for maximal activity. It can be stored at 4 degrees C for long periods with little loss of activity and it can be repeatedly used without alteration of its enzymic capacity. Attachment of ALA-D to the gel has led to an enhanced thermal stability. pH optima of free and bound enzyme was the same while a small decrease in the Km of the matrix bonded ALA-D as compared to that of the soluble enzyme was observed. The use of the fixed-ALA-D for the preparation of PBG is described.
D000818:Animals; D002417:Cattle; D004355:Drug Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D006836:Hydro-Lyases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008722:Methods; D011162:Porphobilinogen / Q000096:biosynthesis; D000623:Porphobilinogen Synthase / Q000378:metabolism*; D012685:Sepharose; D013696:Temperature
D004800:Enzymes, Immobilized; D011162:Porphobilinogen; D012685:Sepharose; D006836:Hydro-Lyases; D000623:Porphobilinogen Synthase