Clostridium ljungdahlii

The first step in the process is gasification of wood followed by conditioning and cleaning of the synthesis gas to give a mixture rich in CO and H2. The synthesis gas is sparged into a broth-filled tank fermentor where bacteria Clostridium ljungdahlii, for example) convert CO and CO2 to ethanol via the following two reactions ... 

Lactococcus lactis Propionibacterium shermani Coiynebacterium glutamicum Gluconobacter oxydans Lactobacillus casei Lactobacillus delbrueckii Lactobacillus plantarum Propionibacteriurn acidiprop. Rhizopus oiyzae Lactobacillus delbrueckii Lactococcus lactis Lactobacillus delbrueckii Lactococcus lactis Lactobacillus delbrueckii Streptococcus, Lactobacil lus, Propion i bacteri urn Clostridium ljungdahlii Ciyptococcus neoformans... 

Kopke M, Held C, Hujer S, Liesegang H, Wiezer A, Wollherr A, Ehrenreich A, Liebel W, GottschaUc G, Durre P. (2010) Clostridium ljungdahlii represents a microbial production platform based on syngas. Proc Natl Acad SciU S A, 107, 13087-13092. 

Leang C, Ueki T, Nevin K, Lovley D. (2013) A genetic system for Clostridium ljungdahlii a chassis for autotrophic production of biocommodities and a model homoacetogen. Appl Environ Microbiol. 19, 1102-1109. 

Synthesis gas, a mixture of mainly CO, CO2, and H2, has been used in chemical industry as feedstock and can be generated by gasification of coal and oil but also from biomass, municipal waste, or by recycling of used plastics (Kopke et al., 2010). Isobutanol production from synthesis gas has so far not been reported. However, Kopke et al. (2010) engineered Clostridium ljungdahlii, which is naturally able to use synthesis gas as carbon and energy source, for the production of 1-butanol by implementation of the CoA-dependent 1-butanol synthesis pathway from Clostridium acetobutylicum. The final titer of about 0.5 mM 1-butanol was rather low however, this approach demonstrated the feasibility to produce fuels and chemicals from synthesis gas. 

Cotter, J.L., Chinn, M.S., Grtmderr, A.M., 2009a. Ethanol and acetate production by Clostridium ljungdahlii and Clostridium autoethanogenum using resting cells. Bioprocess and Biosystems Engineering 32 (3), 369—380. 

Tanner, R.S., Miller, L.M., Yang, D., 1993. Clostridium ljungdahlii sp-nov, an acetogenic species in clostridial ribosomal-RNA homology group-I. International Journal of Systematic Bacteriology 43 (2), 232—236. 

Butyribacterium methylotrophicum Clostridium autoethanogenum Clostridium carboxidivorans Clostridium ljungdahlii... 

Younesi, H., Najafpour, G., Mohamed, A.R., 2005. Ethanol and acetate production from synthesis gas via fermentation processes using anaerobic bacterium, Clostridium ljungdahlii. Biochemical Engineering Journal 27 (2), 110—119. 

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