Linked Life Data

8817489

Source:http://linkedlifedata.com/resource/pubmed/id/8817489

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1996-12-20
pubmed:databankReference
pubmed:abstractText
Two divergently transcribed operons in Escherichia coli required for the expression of fibronectin- and Congo red-binding curli polymers were identified and characterized by transposon mutagenesis, sequencing and transcriptional analyses, as well as for their ability to produce the curli subunit protein. The csgBA operon encodes CsgA, the major subunit protein of the fibre, and CsgB, a protein with sequence homology to CsgA. A non-polar csgB mutant is unaffected in its production of CsgA, but the subunit protein is not assembled into insoluble fibre polymers. A third open reading frame, orfC, positioned downstream of csgA may affect some functional property of curli since an insertion in this putative gene abolishes the autoagglutinating ability typical of curliated cells without affecting the production of the fibre. The promoter for the oppositely transcribed csgDEFG operon was identified by primer extension and shown, like the csgBA promoter, to be dependent upon the alternate stationary phase-specific sigma factor sigma s in wild-type cells, but not in mutants lacking the nucleoid associated protein H-NS. Insertions in csgD abolish completely trancription from the csgBA promoter. Therefore, any regulatory effect on the csgBA promoter might be secondary to events controlling the csgDEFG promoter and/or activation of CsgD. Insertions in csgE, csgF and csgG abolish curli formation but allow CsgA expression suggesting that one or more of these gene products are involved in secretion/assembly of the CsgA subunit protein. No amino acid sequence homologies were found between the CsgE, CsgF and CsgG proteins and secretion/assembly proteins for other known bacterial fibres, suggesting that the formation of curli follows a novel pathway.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
661-70
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:8817489-Bacterial Proteins, pubmed-meshheading:8817489-Blotting, Northern, pubmed-meshheading:8817489-Blotting, Western, pubmed-meshheading:8817489-DNA Transposable Elements, pubmed-meshheading:8817489-Escherichia coli, pubmed-meshheading:8817489-Escherichia coli Proteins, pubmed-meshheading:8817489-Fibronectins, pubmed-meshheading:8817489-Gene Expression Regulation, Bacterial, pubmed-meshheading:8817489-Genes, Bacterial, pubmed-meshheading:8817489-Microscopy, Electron, pubmed-meshheading:8817489-Molecular Sequence Data, pubmed-meshheading:8817489-Mutagenesis, Insertional, pubmed-meshheading:8817489-Open Reading Frames, pubmed-meshheading:8817489-Operon, pubmed-meshheading:8817489-Promoter Regions, Genetic, pubmed-meshheading:8817489-Sigma Factor, pubmed-meshheading:8817489-Transcription, Genetic
pubmed:year
1995
pubmed:articleTitle
Expression of two csg operons is required for production of fibronectin- and congo red-binding curli polymers in Escherichia coli K-12.
pubmed:affiliation
Microbiology and Tumorbiology Center, Karolinska Institute, Stockholm, Sweden. Marten.Hammar@mtc.ki.se
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't