Search results
Results from the WOW.Com Content Network
In gram-positive bacteria, a protein or polysaccharide surface layer serves as the specific adhesin. To effectively achieve adherence to host surfaces, many bacteria produce multiple adherence factors called adhesins. Bacterial adhesins provide species and tissue tropism. Adhesins are expressed by both pathogenic bacteria and saprophytic bacteria.
An S-layer (surface layer) is a cell surface protein layer found in many different bacteria and in some archaea, where it serves as the cell wall. All S-layers are made up of a two-dimensional array of proteins and have a crystalline appearance, the symmetry of which differs between species.
This has an antiphagocytic effect, i.e. macrophages cannot "see" these bacteria as easily as if they were correctly opsonised by antigen. Also, S. aureus expresses fibronectin-binding proteins, which promote binding to mucosal cells and tissue matrices. This protein is also referred to as clumping factor.
Bacteria produce various adhesins including lipoteichoic acid, trimeric autotransporter adhesins and a wide variety of other surface proteins to attach to host tissue. Capsules, made of carbohydrate, form part of the outer structure of many bacterial cells including Neisseria meningitidis.
Protein A is a 42 kDa surface protein originally found in the cell wall of the bacteria Staphylococcus aureus. It is encoded by the spa gene and its regulation is controlled by DNA topology, cellular osmolarity, and a two-component system called ArlS-ArlR. It has found use in biochemical research because of its ability to bind immunoglobulins ...
Lipopolysaccharides are frequent contaminants in plasmid DNA prepared from bacteria or proteins expressed from bacteria, and must be removed from the DNA or protein to avoid contaminating experiments and to avoid toxicity of products manufactured using industrial fermentation. [74] Ovalbumin is frequently contaminated with endotoxins. Ovalbumin ...
The glycocalyx (pl.: glycocalyces or glycocalyxes), also known as the pericellular matrix and cell coat, is a layer of glycoproteins and glycolipids which surround the cell membranes of bacteria, epithelial cells, and other cells. [1] Animal epithelial cells have a fuzz-like coating on the external surface of their plasma membranes.
Bacteria often produce capsules made of proteins or sugars that coat their cells and interfere with phagocytosis. [107] Some examples are the K5 capsule and O75 O antigen found on the surface of Escherichia coli, [111] and the exopolysaccharide capsules of Staphylococcus epidermidis. [112]