title: Microbial solvent formation revisited by comparative genome analysis.
abstract: BACKGROUND
  Microbial formation of acetone, isopropanol, and butanol is largely restricted to bacteria belonging to the genusClostridium. This ability has been industrially exploited over the last 100 years. The solvents are important feedstocks for the chemical and biofuel industry. However, biological synthesis suffers from high substrate costs and competition from chemical synthesis supported by the low price of crude oil. To render the biotechnological production economically viable again, improvements in microbial and fermentation performance are necessary. However, no comprehensive comparisons of respective species and strains used and their specific abilities exist today.
  
  
  RESULTS
  The genomes of a total 30 saccharolyticClostridiumstrains, representative of the speciesClostridium acetobutylicum,C. aurantibutyricum,C. beijerinckii,C. diolis,C. felsineum,C. pasteurianum,C. puniceum,C. roseum,C. saccharobutylicum, andC. saccharoperbutylacetonicum, have been determined; 10 of them completely, and compared to 14 published genomes of other solvent-forming clostridia. Two major groups could be differentiated and several misclassified species were detected.
  
  
  CONCLUSIONS
  Our findings represent a comprehensive study of phylogeny and taxonomy of clostridial solvent producers that highlights differences in energy conservation mechanisms and substrate utilization between strains, and allow for the first time a direct comparison of sequentially selected industrial strains at the genetic level. Detailed data mining is now possible, supporting the identification of new engineering targets for improved solvent production.
authors.affiliation: Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Georg-August University Göttingen, Grisebachstr. 8, 37077 Göttingen, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Poehlein
authors.affiliation: Institut für Mikrobiologie und Biotechnologie, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
authors.forename: José David Montoya
authors.initials: JDM
authors.lastname: Solano
authors.affiliation: Institut für Mikrobiologie und Biotechnologie, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
authors.forename: Stefanie K
authors.initials: SK
authors.lastname: Flitsch
authors.affiliation: Green Biologics Ltd., 45A Western Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RU UK.
authors.forename: Preben
authors.initials: P
authors.lastname: Krabben
authors.affiliation: Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, Nottingham, NG7 2RD UK.
authors.forename: Klaus
authors.initials: K
authors.lastname: Winzer
authors.affiliation: Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, Cape Town, 7701 South Africa.
authors.forename: Sharon J
authors.initials: SJ
authors.lastname: Reid
authors.affiliation: Department of Microbiology and Immunology, University of Otago, Dunedin, 9010 New Zealand.
authors.forename: David T
authors.initials: DT
authors.lastname: Jones
authors.affiliation: CHAIN Biotechnology Ltd., Imperial College Incubator, Level 1 Bessemer Building, Imperial College London, London, SW7 2AZ UK.
authors.forename: Edward
authors.initials: E
authors.lastname: Green
authors.affiliation: Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, Nottingham, NG7 2RD UK.
authors.forename: Nigel P
authors.initials: NP
authors.lastname: Minton
authors.affiliation: Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Georg-August University Göttingen, Grisebachstr. 8, 37077 Göttingen, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Daniel
authors.affiliation: Institut für Mikrobiologie und Biotechnologie, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
authors.forename: Peter
authors.identifier: 0000-0002-5586-221X
authors.initials: P
authors.lastname: Dürre
keywords: Acetone; Butanol; C. beijerinckii; C. saccharobutylicum; C. saccharoperbutylacetonicum; Clostridium acetobutylicum; Phylogeny; Solvents