MODIFIED 6-PHOSPHOFRUCTO-1 -KINASES, WHICH ENABLE FREMENTATIVE GROWTH OF RECOMBINANT YEAST SACCHAROMYCES CEREVISIAE CELLS ON PENTOSE SUGARS

The subject of the invention is the modified glycolytic enzyme 6-phosphofructo-1 -kinase (PFK) that will allow the yeast Saccharomyces cerevisiae cells to fermentatively grow on pentose sugars. The invention belongs to the field of genetic engineering and microbial cells and fermentations or processes for the synthesis of desired chemical compounds, more specifically into the field of fermentative products formation that are based on the expression of the modified genes in the host cell. The essence of the invention is a modification of the gene encoding 6-phosphofructo-1- kinase (PFK), the key regulatory enzyme, of glycolysis that determines the rate of metabolic flux through the initial part of primary metabolism. Modified gene is of human, animal, microbial origin or it is a hybrid. A consequence of modified pfk genes expression in a host cell is the formation of the shorter PFK fragments that have higher activities in respect to the native enzyme. Modified enzymes in combination with NADPH-specific malic enzyme enable the use of pentose sugars and production of fermentative products, in particular 2-phenyethanol.