Linked Life Data

20636372

Source:http://linkedlifedata.com/resource/pubmed/id/20636372

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-1-4
pubmed:abstractText
The stimulation of subsurface microbial metabolism often associated with engineered bioremediation of groundwater contaminants presents subsurface microorganisms, which are adapted for slow growth and metabolism in the subsurface, with new selective pressures. In order to better understand how Geobacter species might adapt to selective pressure for faster metal reduction in the subsurface, Geobacter sulfurreducens was put under selective pressure for rapid Fe(III) oxide reduction. The genomes of two resultant strains with rates of Fe(III) oxide reduction that were 10-fold higher than those of the parent strain were resequenced. Both strains contain either a single base-pair change or a 1 nucleotide insertion in a GEMM riboswitch upstream of GSU1761, a gene coding for the periplasmic c-type cytochrome designated PgcA. GSU1771, a gene coding for a SARP regulator, was also mutated in both strains. Introduction of either of the GEMM riboswitch mutations upstream of pgcA in the wild-type increased the abundance of pgcA transcripts, consistent with increased expression of pgcA in the adapted strains. One of the mutations doubled the rate of Fe(III) oxide reduction. Interruption of GSU1771 doubled the Fe(III) oxide reduction rate. This was associated with an increased in expression of pilA, the gene encoding the structural protein for the pili thought to function as microbial nanowires. The combination of the GSU1771 interruption with either of the pgcA mutations resulted in a strain that reduced Fe(III) as fast as the comparable adapted strain. These results suggest that the accumulation of a small number of beneficial mutations under selective pressure, similar to that potentially present during bioremediation, can greatly enhance the capacity for Fe(III) oxide reduction in G. sulfurreducens. Furthermore, the results emphasize the importance of the c-type cytochrome PgcA and pili in Fe(III) oxide reduction and demonstrate how adaptive evolution studies can aid in the elucidation of complex mechanisms, such as extracellular electron transfer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1462-2920
pubmed:author
pubmed:copyrightInfo
© 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.
pubmed:issnType
Electronic
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13-23
pubmed:meshHeading
pubmed-meshheading:20636372-Adaptation, Physiological, pubmed-meshheading:20636372-Biodegradation, Environmental, pubmed-meshheading:20636372-Cytochrome c Group, pubmed-meshheading:20636372-DNA, Bacterial, pubmed-meshheading:20636372-Electron Transport, pubmed-meshheading:20636372-Evolution, Molecular, pubmed-meshheading:20636372-Ferric Compounds, pubmed-meshheading:20636372-Gene Expression Profiling, pubmed-meshheading:20636372-Genes, Bacterial, pubmed-meshheading:20636372-Genome, Bacterial, pubmed-meshheading:20636372-Geobacter, pubmed-meshheading:20636372-Mutagenesis, Insertional, pubmed-meshheading:20636372-Mutation, pubmed-meshheading:20636372-Oligonucleotide Array Sequence Analysis, pubmed-meshheading:20636372-Oxidation-Reduction, pubmed-meshheading:20636372-Riboswitch, pubmed-meshheading:20636372-Sequence Analysis, DNA
pubmed:year
2011
pubmed:articleTitle
A c-type cytochrome and a transcriptional regulator responsible for enhanced extracellular electron transfer in Geobacter sulfurreducens revealed by adaptive evolution.
pubmed:affiliation
Department of Microbiology, University of Massachusetts, Amherst, MA, USA. pierluct@nre.umass.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.