@article {3130,
	title = {Lactose-inducible system for metabolic engineering of Clostridium ljungdahlii.},
	journal = {Appl Environ Microbiol},
	volume = {80},
	year = {2014},
	month = {2014 Apr},
	pages = {2410-6},
	abstract = {<p>The development of tools for genetic manipulation of Clostridium ljungdahlii has increased its attractiveness as a chassis for autotrophic production of organic commodities and biofuels from syngas and microbial electrosynthesis and established it as a model organism for the study of the basic physiology of acetogenesis. In an attempt to expand the genetic toolbox for C. ljungdahlii, the possibility of adapting a lactose-inducible system for gene expression, previously reported for Clostridium perfringens, was investigated. The plasmid pAH2, originally developed for C. perfringens with a gusA reporter gene, functioned as an effective lactose-inducible system in C. ljungdahlii. Lactose induction of C. ljungdahlii containing pB1, in which the gene for the aldehyde/alcohol dehydrogenase AdhE1 was downstream of the lactose-inducible promoter, increased expression of adhE1 30-fold over the wild-type level, increasing ethanol production 1.5-fold, with a corresponding decrease in acetate production. Lactose-inducible expression of adhE1 in a strain in which adhE1 and the adhE1 homolog adhE2 had been deleted from the chromosome restored ethanol production to levels comparable to those in the wild-type strain. Inducing expression of adhE2 similarly failed to restore ethanol production, suggesting that adhE1 is the homolog responsible for ethanol production. Lactose-inducible expression of the four heterologous genes necessary to convert acetyl coenzyme A (acetyl-CoA) to acetone diverted ca. 60\% of carbon flow to acetone production during growth on fructose, and 25\% of carbon flow went to acetone when carbon monoxide was the electron donor. These studies demonstrate that the lactose-inducible system described here will be useful for redirecting carbon and electron flow for the biosynthesis of products more valuable than acetate. Furthermore, this tool should aid in optimizing microbial electrosynthesis and for basic studies on the physiology of acetogenesis.</p>},
	keywords = {Acetic Acid, Acetone, Acetyl Coenzyme A, Alcohol Dehydrogenase, Carbon, Clostridium, Ethanol, Fructose, Gene Expression, Gene Expression Regulation, Bacterial, Lactose, Metabolic Engineering, Metabolic Flux Analysis, Transcriptional Activation},
	issn = {1098-5336},
	doi = {10.1128/AEM.03666-13},
	author = {Banerjee, Areen and Leang, Ching and Ueki, Toshiyuki and Nevin, Kelly P and Lovley, Derek R}
}
@article {521,
	title = {Two putative c-type multiheme cytochromes required for the expression of OmcB, an outer membrane protein essential for optimal Fe(III) reduction in Geobacter sulfurreducens.},
	journal = {J Bacteriol},
	volume = {188},
	year = {2006},
	month = {2006 Apr},
	pages = {3138-42},
	abstract = {Deletion of two homologous Geobacter sulfurreducens c-type cytochrome genes, omcG and omcH, decreased the rate of Fe(III) reduction and decreased the level of an outer membrane cytochrome critical for Fe(III) reduction, OmcB, without affecting its transcription. Expression of either gene restored Fe(III) reduction and OmcB expression, suggesting functional similarity.},
	keywords = {Bacterial Outer Membrane Proteins, Bacterial Proteins, Blotting, Northern, Blotting, Western, Cytochromes c, Ferric Compounds, Gene Deletion, Gene Expression, Genes, Bacterial, Geobacter, Oxidation-Reduction, RNA, Bacterial, RNA, Messenger},
	issn = {0021-9193},
	doi = {10.1128/JB.188.8.3138-3142.2006},
	author = {Kim, Byoung-Chan and Qian, Xinlei and Leang, Ching and Coppi, Maddalena V and Lovley, Derek R}
}
