Dsm IP Assets B.v.

Maarten Dirk Verhoeven

Jacobus Thomas Pronk

Antonius Jeroen Adriaan Van Maris

Ioannis Papapetridis

Paulus Petrus De Waal

Jozef Petrus Johannes Schmitz

Niels Lauret

The invention relates to a variant of a parent polypeptide which is preferably a hexose transporter, wherein the variant comprises an amino acid sequence which, when aligned with the amino acid sequence of SEQ ID NO: 1, comprises a substitution of amino acids N376 and T89, the positions of said amino acids being defined with reference to the amino acid sequence of SEQ ID NO: 1. Said polypeptide is suitable in the production of ethanol from arabinose-rich biomass such as corn stover and corn starch.

Polypeptides with improved arabinose transport specificity

The invention relates to a method for preparing a yeast which is capable of simultaneously fermenting a pentose and a hexose sugar, the method comprising providing a yeast which comprises: one or more heterologous genes encoding an enzyme of a pentose metabolic pathway, a disruption of a gene encoding a ribulose-phosphate 3-epimerase and a disruption of a gene encoding a glucose-6-phosphate isomerase, and one or more overexpressed endogenous genes encoding an enzyme of the pentose phosphate pathway; and subjecting the yeast to evolutionary engineering on a medium comprising a hexose sugar and at least one pentose sugar, selecting for a yeast with improved growth rate when grown on a media comprising a hexose and at least one pentose sugar, so as to obtain an evolved yeast.

Yeast cell capable of simultaneously fermenting hexose and pentose sugars

The present invention describes a recombinant yeast cell functionally expressing one or more heterologous nucleic acid sequences encoding for ribulose-1,5-phosphate carboxylase/oxygenase (EC4.1.1.39; Rubisco), and optionally one or more molecular chaperones for Rubisco, and one or more phosphoribulokinase (EC2.7.1.19; PRK), wherein the phosphoribulokinase is under control of a promoter (the 'PRK promoter') that enables higher expression under anaerobic conditions than under aerobic conditions.

Growing community of inventors

Delft, Netherlands

Maarten Dirk Verhoeven