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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3-4
|
| pubmed:dateCreated |
1997-10-23
|
| pubmed:abstractText |
The surfaces of bacteria are highly interactive with their environment. Whether the bacterium is Gram-negative or Gram-positive, most surfaces are charged at neutral pH because of the ionization of the reactive chemical groups which stud them. Since prokaryotes have a high surface area-to-volume ratio, this can have surprising ramifications. For example, many bacteria can concentrate dilute environmental metals on their surfaces and initiate the development of fine-grained minerals. In natural environments, it is not unusual to find such bacteria closely associated with the minerals which they have helped develop. Bacteria can be free-living (planktonic), but in most natural ecosystems they prefer to grow on interfaces as biofilms; supposedly to take advantage of the nutrient concentrative effect of the interface, although there must also be gained some protective value against predators and toxic agents. Using a Pseudomonas aeruginosa model system, we have determined that lipopolysaccharide is important in the initial attachment of this Gram-negative bacterium to interfaces and that this surface moiety subtly changes during biofilm formation. Using this same model system, we have also discovered that there is a natural tendency for Gram-negative bacteria to concentrate and package periplasmic components into membrane vesicles which bleb-off the surface. Since some of these components (e.g., peptidoglycan hydrolases) can degrade other surrounding cells, the vesicles could be predatory; i.e., a natural system by which neighboring bacteria are targeted and lysed, thereby liberating additional nutrients to the microbial community. This obviously would be of benefit to vesicle-producing bacteria living in biofilms containing mixed microbial populations.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jul
|
| pubmed:issn |
0168-6445
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
20
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
291-303
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading | |
| pubmed:year |
1997
|
| pubmed:articleTitle |
Interactions between biofilms and the environment.
|
| pubmed:affiliation |
Canadian Bacterial Disease Network-National Centre of Excellence, Guelph, Ont., Canada. tjb@micro.uoguelph.ca
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|