ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Global impact of mature biofilm lifestyle on Escherichia coli K-12 gene expression (2004)

Beloin, Christophe ; Valle, Jaione ; Latour-Lambert, Patricia ; [et al.]

Oxford, UK : Blackwell Science Ltd

Molecular microbiology 51 (2004), S. 0

add to mindlist on the mindlist

Details

ISSN: 1365-2958

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology , Medicine

Notes: The formation of biofilm results in a major lifestyle switch that is thought to affect the expression of multiple genes and operons. We used DNA arrays to study the global effect of biofilm formation on gene expression in mature Escherichia coli K-12 biofilm. We show that, when biofilm is compared with the exponential growth phase, 1.9% of the genes showed a consistent up- or downregulation by a factor greater than two, and that 10% of the E. coli genome is significantly differentially expressed. The functions of the genes induced in these conditions correspond to stress response as well as energy production, envelope biogenesis and unknown functions. We provide evidence that the expression of stress envelope response genes, such as the psp operon or elements of the cpx and rpoE pathways, is a general feature of E. coli mature biofilms. We also compared biofilm with the stationary growth phase and showed that the biofilm lifestyle, although sharing similarities with the stationary growth phase, triggers the expression of specific sets of genes. Using gene disruption of 54 of the most biofilm-induced genes followed by a detailed phenotypic study, we validated the biological relevance of our analysis and showed that 20 of these genes are required for the formation of mature biofilm. This group includes 11 genes of previously unknown function. These results constitute a comprehensive analysis of the global transcriptional response triggered in mature E. coli biofilms and provide insights into its physiological signature.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1046/j.1365-2958.2003.03865.x

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Quantitative analysis of immunogold labellings of collagen types I, III, IV and VI in healthy and pathological human corneas (1995)

Delaigue, Olivier ; Arbeille, Brigitte ; Lemesle, Monique ; [et al.]

Springer

Graefe's archive for clinical and experimental ophthalmology 233 (1995), S. 331-338

add to mindlist on the mindlist

Details

ISSN: 1435-702X

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine

Notes: Abstract • Background: We studied the distribution of collagen types I, III, IV and VI in one healthy human cornea and in seven pathological human corneas, in which the disorders were three cases of pseudophakic bullous keratopathy (two severe, one moderate) and one case each of stage IV keratoconus, chronic ulcer, vascularized cornea and disciform keratitis. • Methods: Transmission electron microscopy examinations were performed on post-embedding immunogold-labelled sections. The staining was evaluated by gold particle count in the different tissues. The presence or absence of a given antigen was determined by statistical analysis, using a d-value test. • Results: Our results on healthy corneal tissues corroborate the data available from previous studies, except for collagen type VI, which we found to be absent in Bowman's layer. In pathological corneas with a collagenous layer posterior to Descemet's membrane, collagen types I, III and especially IV were detected in this collagenous layer. Collagen types I, III and VI were detected in the anterior healed stroma of other pathological corneas, except for the keratoconus cornea, in which intense collagen III staining was observed. • Conclusion: The presence of collagen types I and III in the posterior collagenous layer of our pseudophakic bullous keratopathy corneas suggests that this layer corresponds to scar tissue secreted by stimulated endothelial cells.