Adhesins lectin

Microbial pathogens utilize different types of lectins for targeting the glycans on the surface of host cells. Many bacteria are covered with pili or fimbriae that contain a very special class of lectins known as adhesins because they play a role in attachment to epithelial cells. These lectins are monomeric and comprise only one binding site. Because the adhesins are repeated on the pilus, a larger number of adhesins on the bacterial surface create multivalent interaction with the host glycans. 

Some unusual aminosaccharides can have antibacterial and antibiotic effects this is the case of 3-amino-3-deoxy-D-glucose isolated from deep-sea bacteria (a Bacillus strain) collected at a depth of 4310 m [178]. More importantly, cellular receptors responsible for the adherence of microbes to eukaryotic cells are often lectin-type adhesins [179], and aminosaccharide treatment can result in the protection against microbial infections [ 180]. 

Ofek, I. and Sharon, N. 1990. Adhesins as lectins Specificity and role in infection. Curr. Topics Microbiol. Immun. 151, 91-113. 

Modulation of sialic acid-receptor interactions, e g., increase of the binding of murine B lymphocyte CD22 adhesin and of Escherichia coli K99 lectin decrease of the binding of mouse macrophage sialoadhesin and Myelin-Associated Glycoprotein (MAG) [664-667]... 

Buts L, Bouckaert J, De Genst E et al. (2003) The fimbrial adhesin F17-G of enterotoxigenic E. coli has an immunoglobulin like lectin domain that binds A-acetylgl ucosam i ne. Mol... 

Some of this variety of adhesion may be straightforward double layer effects (see Chapter 10) but there is no doubt that more complicated mechanisms may be involved and that particular polyma- molecules, now identified as adhesins, integrins, lectins, etc., can be influential. The purpose of this chapter is to outline the basic adhesion principles, starting from a definition of cell surface structure, moving on to measurement methods, then finally discussing the peculiar molecular influences. 

The most common group of fimbrial adhesins of Escherichia coli occurs at the edge of their fimbriae and have a two-domain organization. The most external N-terminal domain is a lectin, whereas the C-terminal pilin connects to the rest of the fimbrius. In Fig. 5, the lectin domains from E. coli adhesins that have been crystallised in complex with a specific glycan sequence are displayed, with the exception of CfaE that was only crystallized in its glycan-free form. PapGII (Pap for pyelonephritis associated pili) is the fimbrial adhesin at the tip of P fimbriae from... 

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