Linked Life Data

15612918

Source:http://linkedlifedata.com/resource/pubmed/id/15612918

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-12-22
pubmed:abstractText
MreB proteins of Escherichia coli, Bacillus subtilis and Caulobacter crescentus form actin-like cables lying beneath the cell surface. The cables are required to guide longitudinal cell wall synthesis and their absence leads to merodiploid spherical and inflated cells prone to cell lysis. In B. subtilis and C. crescentus, the mreB gene is essential. However, in E. coli, mreB was inferred not to be essential. Using a tight, conditional gene depletion system, we systematically investigated whether the E. coli mreBCD-encoded components were essential. We found that cells depleted of mreBCD became spherical, enlarged and finally lysed. Depletion of each mre gene separately conferred similar gross changes in cell morphology and viability. Thus, the three proteins encoded by mreBCD are all essential and function in the same morphogenetic pathway. Interestingly, the presence of a multicopy plasmid carrying the ftsQAZ genes suppressed the lethality of deletions in the mre operon. Using GFP and cell fractionation methods, we showed that the MreC and MreD proteins were associated with the cell membrane. Using a bacterial two-hybrid system, we found that MreC interacted with both MreB and MreD. In contrast, MreB and MreD did not interact in this assay. Thus, we conclude that the E. coli MreBCD form an essential membrane-bound complex. Curiously, MreB did not form cables in cell depleted for MreC, MreD or RodA, indicating a mutual interdependency between MreB filament morphology and cell shape. Based on these and other observations we propose a model in which the membrane-associated MreBCD complex directs longitudinal cell wall synthesis in a process essential to maintain cell morphology.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
78-89
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
The morphogenetic MreBCD proteins of Escherichia coli form an essential membrane-bound complex.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't