Bacteria adherence

Recently a phenomenon of resistance to biocide solutions has been recognized (see also Chapters 9 and 13) in which bacteria adhere to a container wall and cover themselves with a carbohydrate slime called a glycocalyx thus, doubly protected (wall and glycocalyx), they have been found to resist biocide attack. 

Whooping cough primarily affects children, with 90% of cases recorded in individuals under 5 years of age. Upon exposure, the bacteria adhere to the cilia of the upper respiratory tract, hence colonizing this area. They then synthesize and release several toxins which can induce both local and systemic damage. 

Pour an additional 10 ml (approximately) of sterile 0.1% Tween solution into each filter using aseptic technique. This rinse is intended to wash the interior walls of the filtration units and carry any bacteria adhering to these surfaces onto the surface of the membrane filter. 

A recent study has shown that some RO membranes are more prone to bioadhesion than others. The study involved a bioadhesion assay, which utilizes a model bacterium, SW 8, known to adhere to membranes. Examination of bacteria adhered to the membranes... 

Bacteria adhere to intestinal epithelial cells with destruction of microvilli... 

Although all oral bacteria adhere to the tooth surface, only... 

Although aU oral bacteria adhere to the tooth surface, only S. mutans causes dental caries, or cavities. Why does this bacterium cause cavities when all the others do not The answer lies in the special enzyme called glucosyl transferase that is found on the surface of S. mutans cells. 

Many bacteria adhere to human cells by binding to sugar moieties on the cell surfaces. In several cases (e.g., Escherichia coli and Helicobacter pylori), the ability to bind can define the virulence of a subspecies of microorganisms, as the property to adhere to humans cells can turn relatively harmless bacteria into hazardous pathogens causing a broad variety of diseases (9). 

In some cases, the SEM substrate can be a TEM grid. More typically, ideal substrates are flat or relatively featureless or both. Pre-cleaned glass or plastic cover slips are commonly used for cell layers and cells that can adhere. Use of pre-cut silicon chips as a substrate is gaining popularity, as these are very flat and featureless and sufficiently conductive to minimize charge buildup in samples. In many cases, cells and bacteria adhere to cover slips and chips without further treatment. If necessary, the substrates can be coated with polypeptides or other agents such as collagen, fibronectin, serum, or polylysine to promote adherence. 

Attachment pilus Type of pilus that helps bacteria adhere to surfaces. 

Pellicle (1) A thin layer of bacteria adhering to the air-water interface of a broth culture by their attachment pili (2) A strengthened plasma membrane of a protozoan cell (3) Film over the surface of a tooth at the begiiming of plaque formation. 

Excellent in cleansing dirt, agricultural chemicals and bacteria adhering to vegetcQjles, fruits, etc. 

Surface charge is important for bacteria adherence to the material surface, and it affects subsequent biofilm formation. Most bacterial cells are negatively charged. Therefore, in general, a positively charged surface is more prone to bacterial adhesion... 

Not only can bacteria adhere to the surface but also macromolecules of all kind. They may kinetically compete with adhering cells and mask the active groups, an effect which is called fouling . 

---