Teknologian Tutkimuskeskus Vtt Oy

Valtion Teknillinen Tutkimuskeskus

Teknologian Tutkimuskeskus Vtt

Danisco Sweeteners Oy

Peter Richard

Merja Penttilä

Laura Ruohonen

John Londesborough

Mervi Toivari

Merja Elisa Penttila

Aristos Aristidou

Joosu Kuivanen

Hans Söderlund

Kari Koivuranta

Heikki Ojamo

Outi Koivistoinen

Harry Boer

Hakan Gros

Dominik Mojzita

Andrei Miasnikov

Anita Teleman

Josef Deutscher

Mira Povelainen

Claire Plazanet-Menut

Satu Hilditch

Ying-Mong Jasmin Wang

Marilyn Wiebe

Satu Hildich

Merja PenttilÄ

Satu Kuorelahti

The present invention relates to a field of genetically modified fungal cells and converting galacturonic acid to meso-galactaric acid, more precisely to a method of producing meso-galactaric acid. The invention further relates to recombinant fungal cells having a specific combination of modifications including but not limited to expression of uronate dehydrogenase enzyme, reduced D-galacturonic acid reductase activity, and furthermore reduced meso-galactaric acid catabolism, as well as uses and methods related thereto.

Method for producing meso-galactaric acid by contacting a fungal cell with a biomaterial having galacturonic acid

The present invention concerns a eukaryotic host selected from microorganisms, and a method for producing glycolic acid using said eukaryotic host cells, especially cells of a genetically modified fungal host. Further this invention relates to a glycolic acid product obtained using the method described here and the use of genetically modified microorganism cells in production of glycolic acid.

Eukaryotic cell and method for producing glycolic acid

A DNA molecule comprising a fungal gene encoding an enzyme protein capable of converting L-galactonic acid into L-threo-3-deoxy-hexulosonic acid has been cloned and heterologously expressed. The enzyme is involved in the metabolic conversion of sugar acids, which are present in biological waste material such as sugar beet pulp and other pectin comprising material. A microorganism genetically modified to effectively express said enzyme may be used in fermenting biomaterial to desired end products such as ethanol. Alternatively, microorganisms in which the gene has been inactivated may be used to produce L-galactonic acid, which accumulates when the expression of the gene is prevented.

Microbial conversion of sugar acids and means therein

Provided is a method for producing xylonic acid from xylose with a recombinant fungal strain that is genetically modified to express a xylose dehydrogenase gene, which is able to convert xylose to xylonolactone, which is spontaneously or enzymatically hydrolyzed to xylonic acid. The xylonic acid is excreted outside the host cell. Xylonate production may be coupled with xylitol production. Alternatively, if xylitol production is not desired, its production is reduced by removing the aldose reductase (or specific xylose reductase) enzyme, which converts xylose to xylitol. Expression of a heterologous lactonase encoding gene may result in higher acid concentrations. The method is suitable for producing xylonic acid from a hemicellulose hydrolysate such as hydrolyzed lignocellulosic plant biomass.

Manufacture of xylonic acid

The present invention relates to a method and microbial host strain for converting a hexuronic acid to a hexaric acid. In particular, the invention relates to the conversion of D-galacturonic acid to meso-galactaric acid (mucic acid). The invention also concerns an isolated nucleotide sequence. According to the present method a microbial host strain genetically modified to express uronate dehydrogenase enzyme (EC 1.1.1.203) is contacted with a biomaterial comprising hexuronic acid and the conversion products are recovered. By using the recombinant microorganisms of the present invention it is possible to treat biomaterials comprising hexuronic acids and thereby decrease the amount of hexuronic acids released to the environment.

Conversion of hexuronic acid to hexaric acid

A fungal microorganism can be engineered by means of genetic engineering to utilise L-arabinose. The genes of the L-arabinose pathway, which were unknown, i.e. L-arabinitol 4-dehydrogenase and L-xylulose reductase, were identified. These genes, together with the known genes of the L-arabinose pathway, form a functional pathway. This pathway can be introduced to a fungus, which is completely or partially lacking this pathway.

Engineering fungi for the utilisation of L-arabinose

The invention relates to the methods of manufacturing five-carbon sugars and sugar alcohols as well as other compounds derived from pentose-phosphate pathway from readily available substrates such a hexoses using metabolically engineered microbial hosts.

Manufacture of five-carbon sugars and sugar alcohols

The present invention relates to genetic engineering of production microorganisms used in biotechnology to improve their properties so that they produce useful products more efficiently. The microorganisms express at least one enzyme that causes the functional coupling of the oxidation and reduction of substrates by two pyridine nucleotide-linked dehydrogenase reactions with different specificities for the NAD/NADH and NADP/NADPH coenzyme couples and so facilitates the transfer of electrons between the two coenzyme couples through the said substrates. In particular the invention relates to increasing the yields of products such as ethanol or amino acids from carbon and nitrogen sources such as biomass comprising hexoes, pentoses or their polymers.

Transformed microorganisms with improved properties

Growing community of inventors

Espoo, Finland

Peter Richard