FACTOID # 19: Cheap sloppy joes: Looking for reduced-price lunches for schoolchildren? Head for Oklahoma!
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Biofilms" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Biofilms
Enlarge
Longest raised mat area is about half a meter long.

A biofilm is a complex aggregation of microorganisms growing on a solid substrate. Biofilms are characterized by structural heterogeneity, genetic diversity, complex community interactions, and an extracellular matrix of polymeric substances.

Contents

Formation

Formation of a biofilm begins with the attachment of free-floating microorganisms to a surface. These first colonists adhere to the surface initially through weak, reversible van der Waals forces. If the colonists are not immediately separated from the surface, they can anchor themselves more permanently using cell adhesion molecules such as pili.


The first colonists facilitate the arrival of other cells by providing more diverse adhesion sites and beginning to build the matrix that holds the biofilm together. Only some species are able to attach to a surface on their own. Others are often able to anchor themselves to the matrix or directly to earlier colonists. Once colonization has begun, the biofilm grows through a combination of cell division and recruitment.


Properties

Biofilms are usually found on solid substrates submerged in or exposed to some aqueous solution. Biofilms consist of many species of bacteria and archaea living within a matrix of excreted polymeric compounds. This matrix protects the cells within it and facilitates communication among them through chemical and physical signals. Some biofilms have been found to contain water channels that help distribute nutrients and signalling molecules. This matrix is strong enough that in some cases, biofilms can become fossilized.


Bacteria living in a biofilm can have significantly different properties from free-floating bacteria, as the dense and protected environment of the film allows them to cooperate and interact in various ways. One benefit of this environment is increased resistance to detergents and antibiotics, as the dense extracellular matrix and the outer layer of cells protect the interior of the community.


Examples

Biofilms are common in nature, as bacteria commonly have mechanisms by which they can adhere to surfaces and to each other. Dental plaque is a biofilm. In industrial environments, biofilms can develop on the interiors of pipes and lead to clogs and corrosion. In medicine, biofilms spreading along implanted tubes or wires can lead to pernicious infections in patients. Biofilms on floors and counters can make sanitation difficult in food preparation areas.


Biofilms can also be harnessed for constructive purposes. For example, many sewage treatment plants include a treatment stage in which waste water passes over biofilms grown on filters, which extract and digest harmful organic compounds.


References

  • Allison, D. G.; Gilbert, P.; Lappin_Scott, H. M.; and Wilson, M. (eds) Community Structure and Co_operation in Biofilms Cambridge: Cambridge University Press. ISBN 0_521_79302_5



  Results from FactBites:
 
About Biofilm (170 words)
BioFilm has recently expanded its Astroglide product line to include a strawberry flavored lubricant and a thicker gel formula.
BioFilm is registered with the Food and Drug Administration and the products have been approved to sell by the FDA.
BioFilm's number one priority is to provide its customers with the best products possible.
Biofilm control (2769 words)
The development of biofilms and the role they play in corrosion and deposition processes may be the most misunderstood and baffling factor in the management of cooling and other industrial water systems.
Biofilm structure is often imagined as a coating of microbial cells and the secreted biopolymer spread evenly across a surface.
Coatings and deposits in the form of biofilm and biofilm with entrapped suspended debris are foulants that most of us can comprehend, but biofilms often lead to the additional formation of mineral scales as well.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m