Sub‐Units of Citrate Oxaloacetate‐Lyase

Abstract

Citrate lyase has been shown to have values for S ° 20,W and D ° 20,W of 17.6 S and 3.02 × 10 −7 cm 2 sec −1 , respectively. Using the Svedberg equation a value of 533000 was assigned for the molecular weight of the active preparation. The meniscus depletion sedimentation equilibrium method led to a value of 550000 while the transient state method gave a value of 566000. The partial specific volume was determined by the 2 H 2 O method of Edelstein and Schachman to be 0.73 ml g −1 . The enzyme was also studied in a variety of denaturing solvents. Molecular weights were measured in the analytical ultracentrifuge and also using dodecylsulphate‐polyacrylamide‐gel electrophoresis with marker proteins of known molecular weight. A range of particles resulted suggesting that there could be 16 sub‐units in the active enzyme preparation.