Microorganisms attachment

MicrobiologicaHy influenced corrosion, which results from the interaction of microorganisms and a metal, is receiving increased emphasis (1,3,9). The action of microorganisms is at least one of the reasons why natural seawater is more corrosive than either artificial seawater or sodium chloride solutions. Microorganisms attach to the surfaces of metals and can, for example, act as diffusion barriers produce metaboHtes that enhance or initiate... 

Dental plaque Mass of microorganisms attached to a tooth surface. 

It is well known that pine enzymes change then behaviour and stability when they are immobilised. In the past two decades the immobilisation of microorganisms, cells and parts of cells has gradually been introduced into microbiology and biotechnology. The cell immobilisation techniques are modifications of the techniques developed for enzymes. However, the larger size of microbes has influenced the techniques. As for immobilised enzymes, two broad types of method have been used to immobilise microorganisms attachment to a support and entrapment. 

Contact lens care products can be divided into three categories cleaners, disinfectants, and lubricants. Improperly cleaned lenses can cause discomfort, irritation, decrease in visual acuity, and giant papillary conjunctivitis (GPC). This latter condition often requires discontinuation of lens wear, at least until the symptoms clear. Deposits can also accumulate preservatives from lens care products and produce toxicity and can act as a matrix for microorganism attachment to the lens [317]. Thus, cleaning with the removal of surface debris, tear components, and contaminating microorganisms is one of the most important steps contributing to the safety and efficacy of successful lens wear [318]. 

Biofilms are abundant in a multitude of aquatic environments in which they cover all kinds of inorganic and organic solid surfaces. Biofilms can be defined as microorganisms attached to a surface and embedded in an extracellular gellike matrix of polymeric substances. This matrix is excreted by the microorganisms themselves and may be enriched by molecules adsorbed from the surrounding water. 

While directly quantifying the numbers of microorganisms attached to the surface of a polymer by enumeration of colonies following incubation on a suitable medium has been widely used to indicate the amount of growth supported on the polymer surface (Christensen et al., 1995), it has a number of severe limitations. The technique depends on a... 

Mott and Bott illustrated the effect of different materials on the accumulation of Pseudomonas fluor-escens biofilms on the inside of tubes under identical operating conditions (see Fig. 9). The differences between the effects of the materials occur for two reasons roughness and surface electrical properties. The quality of the surface, in terms of roughness, on which microorganisms attach, can affect the biofilm accumulation as discussed earlier. The effect of roughness is illustrated in Fig. 9 by the difference of biofilm accumulation between electropolished and as received 316 stainless steel. The rougher stainless steel is seen to be more hospitable to biofilm growth. 

Microorganisms attach themselves to most surfaces and then multiply ... 

Microorganisms attach to host cells via an often unique and speciflc process. Microbial surface structures called adhesins react and combine with complementary receptor sites on host cells. The specific interaction is how individual microbial strains demonstrate a predilection for a particular host body site [3]. 

The contaminating microorganisms must be able to multiply within the person. For example. Salmonella spp. and related microorganisms attach to the walls of the intestinal tract and subsequently colonize it. 

Turbidity is an important characteristic in drinking water supplies because microorganisms attached to particles... 

Adhesin A protein or glycoprotein on attachment pili (fimbriae) or capsules that help a microorganism attach to a host cell. 

The Michaelis-Menten kinetics model, illustrated for a lake in Example 2.20, may also be applied to a flowing stream in which the microorganisms are attached to the surfaces of the charmel, have a relatively steady cell density, and are exposed to the full chemical concentration in the stream (Cohen et al., 1995 Kim et al., 1995). Microorganisms attached to solid surfaces form biofilms, as populations of attached microbes accumulate on top of one another, building up a layer of microbes embedded in an extracellular matrix which they secrete. Within biofilms, the microbial cell density X corresponds to the number of attached microorganisms divided by the volume of the biofilm. In wastewater treatment engineering, a biofilm is often referred to as attached growth. A biofilm may also be called a bacterial... 

---