Linked Life Data

18786181

Source:http://linkedlifedata.com/resource/pubmed/id/18786181

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-1-14
pubmed:abstractText
Pseudomonas fluorescens SBW25 is a plant growth-promoting bacterium that efficiently colonizes the leaf surfaces and rhizosphere of a range of plants. Previous studies have identified a putative plant-induced nitrilase gene (pinA) in P. fluorescens SBW25 that is expressed in the rhizosphere of sugar beet plants. Nitrilase enzymes have been characterised in plants, bacteria and fungi and are thought to be important in detoxification of nitriles, utilisation of nitrogen and synthesis of plant hormones. We reveal that pinA is a NIT4-type nitrilase that catalyses the hydrolysis of beta-cyano-L-alanine, a nitrile common in the plant environment and an intermediate in the cyanide detoxification pathway in plants. In plants cyanide is converted to beta-cyano-L-alanine, which is subsequently detoxified to aspartic acid and ammonia by NIT4. In P. fluorescens SBW25 pinA is induced in the presence of beta-cyano-L-alanine, and the beta-cyano-L-alanine precursors cyanide and cysteine. pinA allows P. fluorescens SBW25 to use beta-cyano-L-alanine as a nitrogen source and to tolerate toxic concentrations of this nitrile. In addition, pinA is shown to complement a NIT4 mutation in Arabidopsis thaliana, enabling plants to grow in concentrations of beta-cyano-L-alanine that would otherwise prove lethal. Interestingly, over-expression of pinA in wild-type A. thaliana not only resulted in increased growth in high concentrations of beta-cyano-L-alanine, but also resulted in increased root elongation in the absence of exogenous beta-cyano-L-alanine, demonstrating that beta-cyano-L-alanine nitrilase activity can have a significant effect on root physiology and root development.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1365-313X
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
57
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
243-53
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
A conserved mechanism for nitrile metabolism in bacteria and plants.
pubmed:affiliation
Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't