Protein antigenic structures

Thus, with this goal In mind, and In order to circumvent the aforementioned problems and render the determination of protein antigenic structures more feasible within a reasonable time, we have devised (5) a novel comprehensive synthetic approach designed to yield the full antigenic profile of the protein under study. This approach consists of the direct synthesis and examination of the immunochemical activities of a series of overlapping peptides having uniform size and overlaps and that encompass the... 

J. A. Berzofsky, Intrinsic and extrinsic factors in protein antigenic structure, Science. 229, 932-940 (1985). 

Steinbacher, S., Miller, S., Baxa, U., Budisa, N., Weintraub, A., Seckler, R., and Huber, R. (1997). Phage P22 tailspike protein Crystal structure of the head-binding domain at 2.3 A, fully refined structure of the endorhamnosidase at 1.56 A resolution, and the molecular basis of O-antigen recognition and cleavage. J. Mol. Biol. 267, 865-880. 

Fig. 7. Kinetics of return of native antigenic structure in various limited regions of reduced albumin as determined with restricted populations of antialbumin. Reduced protein was reoxidized in the presence of optimal amounts of rat liver disulfide-exchange enzyme (0.5 mg/ml of RII/2.5 ml of reaction mixture). The reoxidation buffer and other conditions were as described in Section II. (A) 0, Anti-T 5 1M , anti- Tstt-mi anti-N-fragment antialbumin, anti-C-ffagment and anti anti-T,M, j.

Noncovalently bound adducts can also be observed, involving enzyme and substrate, protein and ligand, protein and protein, antigen and antibody that can influence the biological activity of the cells [26]. The study and the detection of noncovalent complexes has the benefit of enormous advantages using ESI-MS because it requires a lower amount of material and a shorter time to provide structural information. 

This article focuses mainly on the Immunology of proteins whose complete antigenic structures have been chemically localized and synthetically confirmed. These are Mb, lysozyme, Hb and serum albumin. The antigenic sites of many other proteins are now being Investigated. 

Figure 1. A schematic diagram showing the mode of folding of Mb and Its antigenic structure. The solid black portions represent segments which have been shown to comprise accurately the antigenic sites of the protein. The striped parts, each corresponding to one amino acid residue only, can be part of the antigenic sites with some antisera. The dotted portions represent parts of the molecule which have been shown exhaustively to reside outside antigenic sites (1).

In spite of the aforementioned points of resemblance between the antigenic structures of Mb and lysozyme, the antigenic sites of these two proteins are radically different In structural terms (4). The five antigenic sites of Mb are each made up of residues tTTat are directly linked to one another by peptide bonds (U. 

The antibody response to protein antigens has been extensively studied. As briefly outlined, the complete antigenic structures of several proteins have now been determined by chemical methods and confirmed by synthesis (for reviews, see refs. 1,4,35,44). 

In contrast to polysaccharides, protein antigens do have tertiary structure in solution this leaves only a limited number of amino acid sequences exposed at the surface of the molecule. Of these determinants, few, if any, will be repetitive. It would therefore be ex-... 

Renart, J., Reizer, J., and Stark, G. R. (1979) Transfer of proteins from gels to diazobenzyloxymethyl-paper and detection with antisera- a method for studying antibody specificity and antigen structure Proc Natl Acad Sci USA 76, 3116-3120... 

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