Heterologous expression of a deuterated membrane-integrated receptor and partial deuteration in methylotrophic yeasts

Methylotrophic yeast has previously been shown to be an excellent system for the cost-effective production of perdeuterated biomass and for the heterologous expression of membrane receptors. A protocol for the expression of 85% deuterated, functional human -opiate receptor was established. For partially deuterated biomass, deuteration level and distribution were determined for fatty acids, amino acids and carbohydrates. It was shown that prior to biosynthesis of lipids and amino acids (and of carbohydrates, to a lower extent), exchange occurs between water and methanol hydrogen atoms, so that 80%–90% randomly deuterated biomass and over-expressed proteins may be obtained using only deuterated water.