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 fo r the cost-effective production of perdeuterated biomass and for the hetero logous expression of membrane receptors. A protocol for the expression of 8 5% deuterated, functional human mu-opiate receptor was established. For par tially deuterated biomass, deuteration level and distribution were determin ed 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 tha t 80%-90% randomly deuterated biomass and over-expressed proteins may be ob tained using only deuterated water.