Adhesins

S. Langermann, el al., Receptor binding studies disclose a novel class of high-affinity inhibitors of the Escherichia coli FimH adhesin, Mol. Microbiol., 55 (2005) 441 155. 

Porcilis porcoli (combination vaccine containing r-E. coli adhesins) Intervet Active immunization of sows... 

Bacterial adhesin right-hand-twisted, trimeric /8-solenoids with ... 

The repeat sequences in solenoid proteins are often so imperfect that it is difficult to identify them without knowledge of the 3D structure or other supplementary information. In highly regular /1-solenoids, such as antifreeze proteins (Leinala et al., 2002 Liou et al., 2000) or YadA adhesin (Nummelin et al., 2004), the repeats are of the same length and sequence similarity between the repeats is discernible (so-called overt repeats). Frequently, however, the repeats in a given /1-solenoid vary in length because additional residues may be inserted at turn sites without disrupting the pattern of /1-strands that stabilizes the structure (Steinbacher et al., 1994 Yoder et al., 1993). In these cases, the structural repeats are not apparent as sequence repeats (covert repeats). 

Kajava, A. V., Cheng, N., Cleaver, R., Kessel, M., Simon, M. N., Willery, E., Jacob-Dubuisson, F., Locht, C., and Steven, A. C. (2001). Beta-helix model for the filamentous haemagglutinin adhesin of Bordetella pertussis and related bacterial secretory proteins. Mol. Microbiol. 42, 279-292. 

Nummelin, H., Merckel, M. C., Leo, J. C., Lankinen, H., Skurnik, M., and Goldman, A. (2004). The Yersinia adhesin YadA collagen-binding domain structure is a novel left-handed parallel beta-roll. EMBOJ. 23, 701-711. 

Recombinant GM-CSF (produced in Escherichia coli, yeast or COS cells) has been tested for its ability to affect haematopoiesis in primates and humans. Because of its relatively short half-life in the circulation, daily administration (usually via intravenous infusion) is required. Administration results in a transient neutropenia, monocytopenia and eosinopenia within 30 min of administration, presumably because of the ability of GM-CSF to stimulate the expression of adhesins and hence increase the numbers of leukocytes adhered to the capillary endothelium in the marginated pool. Additionally, these leukocytes may accumulate in the lungs after GM-CSF administration, which may contribute to the decrease in the observed numbers... 

The peroxidase-negative granules produced later in neutrophil development are termed secondary or specific granules (because they stain only with specific dyes). They are twice as abundant in the cytoplasm of the mature neutrophil as the azurophilic granules. Specific granules contain much of the lysozyme, lactoferrin, vitamin-B 12-binding protein, adhesin receptors, fMet-Leu-Phe receptors, and cytochrome b.245. 

Figure 3.7. Mode of action of binding of adhesins. The adhesion molecules are shown with their a- and /J- subunits. They may bind (a) extracellular matrix molecules, such as iibronectin, (b) bind directly to other adhesion molecules, such as ICAM-1, or (c) else bind to other adhesion molecules via molecules, such as Iibronectin. Source Redrawn from Ruoslahti (1991).

CR3 comprises two polypeptides, an a-subunit of 185 kDa and a -sub-unit of 95 kDa, which are covalently linked into an a fl structure. Both chains are exposed at the cell surface, whilst the a-chain forms the major portion of the ligand-binding site. The /J-subunit is common to the other adhesins, LFA-1 and pi50,95. These have an antigenically-distinct a-chain but a common /J-chain (see Fig. 3.6). Of these three receptors with common j3-chains, only CR3 binds significant amounts of C3bi. 

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