Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-12-14
pubmed:abstractText
Pseudomonas fluorescens B52 produces substantial biofilms at the air/liquid/solid interface of glass coverslips clamped vertically and partly submerged in liquid medium at 21 degrees C. Biofilm formation was maximal ca. 20-50 h after inoculation of the liquid medium and as indicated by environmental scanning electron microscopy (ESEM), contained large numbers of bacterial cells that were embedded within an extensive exopolymeric matrix. Incubation beyond 50 h led to reductions in biofilm which ESEM related primarily to losses of exopolymer. Both biofilm formation and the subsequent decline in exopolymer deposition was more rapid, and occurred to greater extents, when supernatants from two-day old cultures of B52 were used as the initial growth media. The addition of N-acyl-hexanoyl homoserine lactone to fresh growth medium had a similar effect upon biofilm formation as using spent culture medium. Homoserine lactones could not be demonstrated in spent culture supernatants by an Agrobacterium tumefaciens bioassay. An exopolysaccharide lyase was detected in spend culture media taken from dense biofilm cultures whose action was specifically directed towards biofilm exopolysaccharide. Results suggest that (i) cell-cell signals such as homoserine lactones are associated with the formation of P. fluorescens biofilms, (ii) the enzymic degradation of exopolymers has a specific role in the detachment of cells under starvation conditions, and (iii) whilst short chain (C6) exogenous homoserines can trigger such response in P. fluorescens, its own signal substance is likely to possess a longer (> C8) fatty acyl chain.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0378-1097
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
167
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
179-84
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Extracellular products as mediators of the formation and detachment of Pseudomonas fluorescens biofilms.
pubmed:affiliation
School of Pharmacy and Pharmaceutical Sciences, University of Manchester, UK. dallison@fs1.pa.man.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't