Linked Life Data

12634347

Source:http://linkedlifedata.com/resource/pubmed/id/12634347

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 3
pubmed:dateCreated
2003-3-13
pubmed:abstractText
Pseudomonas putida F1 can assimilate benzene, toluene and ethylbenzene using the toluene degradation pathway, and can also utilize p-cymene via p-cumate using the p-cymene and p-cumate catabolic pathways. In the present study, P. putida F1 strains were isolated that were adapted to assimilate new substrates such as n-propylbenzene, n-butylbenzene, cumene and biphenyl, and the molecular mechanisms of genetic adaptation to an expanded range of aromatic hydrocarbons were determined. Nucleotide sequence analyses showed that the selected strains have mutations in the cymR gene but not in todF gene. The impairment of the repressor CymR by mutation led to the constitutive expression of CmtE, a meta-cleavage product hydrolase from the cmt operon. This study also showed that CmtE has a broad range of substrates and can hydrolyse meta-cleavage products formed from biphenyl and other new growth substrates via the toluene degradation pathway. However, the artificially constructed strain P. putida F1(cymR : : Tc(r)) and a recombinant P. putida F1, which expressed CmtE constitutively, could not grow on the new substrates. The adapted strains possess the tod operon, which is induced by new growth substrates that are poor inducers of wild-type P. putida F1. When the todS gene from the adapted strains was introduced in a trans manner to P. putida F1(cymR : : Tc(r)), the resulting recombinant strains were able to grow on biphenyl and other new substrates. This finding indicates that the TodS sensor was altered to recognize these substrates and this conclusion was confirmed by nucleotide sequence analyses. Amino acid substitutions were found in the regions corresponding to the receiver domain and the second PAS domain and their boundaries in the TodS protein. These results showed that P. putida F1 adapted strains capable of growth on n-propylbenzene, n-butylbenzene, cumene and biphenyl possess mutations to employ CmtE and to induce the tod catabolic operon by the new growth substrates.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1350-0872
pubmed:author
pubmed:issnType
Print
pubmed:volume
149
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
795-805
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Expansion of growth substrate range in Pseudomonas putida F1 by mutations in both cymR and todS, which recruit a ring-fission hydrolase CmtE and induce the tod catabolic operon, respectively.
pubmed:affiliation
Department of Microbiology, Changwon National University, Kyongnam 641-773, Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't