Characterization of lignoceroyl-CoA ligase activity in chicken liver microsomes

Lignoceroyl-coenzyme A (CoA) ligase activity was detected in microsomal fractions from chicken liver in the presence of alpha-cyclodextrin as a solubilizing agent of lignoceric acid. Heptakis(2,6-di-O-methyl)-beta-cyclodextrin (dimethyl-beta-cyclodextrin) and hexakis(2,6-di-O-methyl)-alpha-cyclodextrin (dimethyl-alpha-cyclodextrin), among the cyclodextrins tested, were more effective than alpha-cyclodextrin as solubilizing agents. We have characterized lignoceroyl-CoA ligase activity in comparison with palmitoyl-CoA ligase activity. Lignoceroyl-CoA and palmitoyl-CoA ligase activities showed a similar dependency on CoA concentration. However, lignoceroyl-CoA ligase activity exhibited responses to the Mg2+ ion, adenosine triphosphate (ATP), ATP analogues (adenosine monophosphate (AMP) and adenosine diphosphate (ADP)), and heat treatment, which were distinctly different from the responses of palmitoyl-CoA ligase activity. These results are consistent with the idea that lignoceroyl-CoA and palmitoyl-CoA are synthesized by two different enzymes.