Yeast cells having reductive TCA pathway from pyruvate to succinate and overexpressing an exogenous NAD(P)+ transhydrogenase enzyme

A recombinant yeast cell engineered to produce succinate through an active reductive tricarboxylic acid (TCA) pathway from pyruvate or phosphoenolpyruvate to succinate, wherein the recombinant yeast cell is modified from a parent yeast cell by having integrated into its genome an exogenous gene encoding a soluble nicotinamide adenine dinucleotide phosphate (NAD(P)+) transhydrogenase enzyme, wherein the soluble NAD(P)+transhydrogenase enzyme is expressed in the cytosol of the recombinant yeast cell, wherein the recombinant yeast cell is further modified from the parent yeast cell by having integrated into its genome at least one of:

• (i) an exogenous pyruvate carboxylase gene that encodes an enzyme which catalyzes the conversion of pyruvate to oxaloacetate;
• (ii) an exogenous malate dehydrogenase gene which encodes an enzyme that catalyzes the conversion of oxaloacetate to malate;
• (iii) an exogenous fumarase gene that encodes an enzyme which catalyzes the conversion of malate to fumarate;
• and
• (iv) an exogenous fumarate reductase gene which encodes an enzyme which catalyzes the conversion of fumarate to succinate, and wherein the recombinant yeast cell produces more succinate through the active reductive TCA pathway as compared to the parent cell.