Synthesis and activity of the archazolid western hemisphere.

A convergent and scalable synthesis of the archazolid western hemisphere has been completed. The V-ATPase inhibitory activity of this compound along with a previously prepared eastern domain was then tested using a convenient Arabidopsis-based V-ATPase assay.

Polymer-protomer transition of acetyl-CoA carboxylase occurs in vivo and varies with nutritional conditions.

The protomeric form of purified acetyl coenzyme A carboxylase is inactivated by the binding of avidin to the biotinyl prosthetic group; the catalytically active filamentous form of the enzyme is resistant to avidin. This differential sensitivity to avidin was used to examine the influence of nutritional state on the proportion of polymeric and protomeric carboxylase occurring in avian liver. Hepatic carboxylase was 80% avidin-resistant (polymeric) in the fed chick.