Novel extreme thermophilic bacteria of the genus caldicellulosiruptor

Abstract

The present disclosure pertains to novel isolated cellulolytic extreme thermophilic bacterial cells belonging to the genus Caldicellulosiruptor, mutants thereof, isolated strains, microbial cultures and microbial compositions. The novel bacteria are in particular suitable for the production of fermentation products such as ethanol and lactic acid from lignocellulosic biomass.

1 . An isolated  Caldicellulosiruptor  sp. cell comprising a 16S rDNA sequence which is at least 99%, 99.2%, 99.4%, 99.6%, 99.8%, 99.9% or 100% identical to SEQ ID NO 1, SEQ ID NO 2, SEQ ID NO 3, SEQ ID NO 4, SEQ ID NO 5, SEQ ID NO 6 or SEQ ID NO 7. 
     
     
         2 . The isolated cell according to  claim 1 , wherein the cell is capable of growing in a medium comprising a lignocellulosic biomass material. 
     
     
         3 . The isolated cell according to  claim 2 , wherein the lignocellulosic biomass material is selected from the group consisting of grass, switch grass, cord grass, rye grass, reed canary grass, mixed prairie grass, miscanthus, sugar-methoding residues, sugarcane bagasse, sugarcane straw, agricultural wastes, rice straw, rice hulls, barley straw, corn cobs, cereal straw, wheat straw, canola straw, oat straw, oat hulls, corn fiber, stover, soybean stover, corn stover, cotton stalks, forestry wastes, recycled wood pulp fiber, paper sludge, sawdust, hardwood, and softwood. 
     
     
         4 . The isolated cell according to  claim 3 , wherein the lignocellulosic biomass material is subjected to mechanical, thermochemical, and/or biochemical pretreatment. 
     
     
         5 . The isolated cell according to  claim 4 , wherein pretreating the lignocellulosic biomass material comprises exposing the lignocellulosic biomass to steam treatment. 
     
     
         6 . The isolated cell according to  claim 4  wherein pretreating the lignocellulosic biomass material comprises mechanical comminution and a subsequent treatment with sulfurous acid or its anhydride under heat and pressure with a sudden release of pressure. 
     
     
         7 . The isolated cell according to  claim 1 , which is capable of producing a fermentation product selected from the group consisting of an acid, an alcohol and hydrogen. 
     
     
         8 . The isolated cell according to  claim 7 , wherein the alcohol is selected from the group consisting of ethanol, butanol, propanol, methanol, propanediol and butanediol. 
     
     
         9 . The isolated cell according to  claim 7 , wherein the acid is selected from the group consisting of lactic acid, propionic acid, acetic acid, succinic acid, malic acid, butyric acid and formic acid. 
     
     
         10 . The isolated cell according to  claim 7 , wherein the acid is lactic acid or a salt or ester thereof. 
     
     
         11 . The isolated cell according to  claim 1 , wherein one or more genes have been inserted, deleted or substantially inactivated. 
     
     
         12 . The isolated cell according to  claim 1 , which is DIB041C (DSMZ Accession number 25771) or a mutant thereof. 
     
     
         13 . The isolated cell according to  claim 1 , which is DIB087C (DSMZ Accession number 25772) or a mutant thereof. 
     
     
         14 . The isolated cell according to  claim 1 , which is DIB103C (DSMZ Accession number 25773) or a mutant thereof. 
     
     
         15 . The isolated cell according to  claim 1 , which is DIB104C (DSMZ Accession number 25774) or a mutant thereof. 
     
     
         16 . The isolated cell according to  claim 1 , which is DIB107C (DSMZ Accession number 25775) or a mutant thereof. 
     
     
         17 . The isolated cell according to  claim 1 , which is DIB004C (DSMZ Accession number 25177) or a mutant thereof. 
     
     
         18 . The isolated cell according to  claim 1 , which is DIB101C (DSMZ Accession number 25178) or a mutant thereof. 
     
     
         19 . An isolated strain of the genus  Caldicellulosiruptor , wherein the strain is selected from the group consisting of  Caldicellulosiruptor  sp. DIB041C, deposited as DSM 25771,  Caldicellulosiruptor  sp. DIB087C, deposited as DSM 25772,  Caldicellulosiruptor  sp. DIB103C, deposited as DSM 25773,  Caldicellulosiruptor  sp. DIB104C, deposited as DSM 25774,  Caldicellulosiruptor  sp. DIB107C, deposited as DSM 25775,  Caldicellulosiruptor  sp. DIB 101 C, deposited as DSM 25178 and  Caldicellulosiruptor  sp. DIB004C, deposited as DSM 25177, microorganism derived therefrom, progenies or mutants thereof. 
     
     
         20 . The isolated strain of  claim 19 , having one or more of the following characteristics:
 a) it is a microorganism of the genus  Caldicellulosiruptor;  and/or   b) it is a microorganism of the species  Caldicellulosiruptor saccharolyticus;  and/or   c) in a DNA-DNA hybridization assay, it shows a DNA-DNA relatedness of at least 80%, optionally at least 90%, at least 95%, optionally at least 98%, optionally at least 99%, and optionally at least 99.9% with one of the strains of  claim 19 ; and/or   c) it displays a level of 16S rDNA gene sequence similarity of at least 98%, optionally at least 99%, at least 99.5% or at least 99.7%, optionally 99.99% with one of the strains listed in  claim 19 ; and/or   d) it is capable of surviving and/or growing and/or producing a fermentation product selected from the group consisting of acids and alcohols at temperature conditions above 70° C., in particular of above 72° C.   
     
     
         21 - 25 . (canceled)