Degradation of polypeptide

T. V. Brennan, S. Clarke, Spontaneous Degradation of Polypeptides at Aspartyl and Asparaginyl Residues Effects of the Solvent Dielectric , Protein Sci. 1993, 2, 331 -338. 

Brennan TV, Clarke S. Spontaneous degradation of polypeptides at aspartyl and asparaginyl residues effects of the solvent dielectric. Protein Sci 1993 2(3) 331 338. 

Figure 2. Reaction Scheme and Postulated Intermediates for the Sequential C-Terminal Degradation of Polypeptides Which may Contain Proline.

H.S. Wiley, D.D. Cunningham, A steady state model for analyzing the cellular binding, internalization and degradation of polypeptide ligands,... 

Stepwise degradation of polypeptides involving benzoylation, conversion to azides and treatment of the azides with benzyl alcohol this treatment yields, via rearrangement to isocyanates, carbobenzoxy compounds which undergo catalytic hydrogenation and hydrolysis to the amide of the degraded peptide ... 

Aminopeptidase N (EC 3.4.11) was shown to occur selectively in pericytes of brain capillaries (Krause et al. 1992). Fxmctionally this enzyme is involved in the degradation of polypeptides including bioactive peptides (Kenney and Turner 1987), such as those with vasoactive properties. The enzyme may therefore be a component of the blood-brain barrier modifying neuropeptides which themselves alter vascular permeability. In experimental allergic encephalomyelitis there is a down-regulation of pericyte aminopeptidase N accompanying the well-known transient and focal perturbation of the blood-brain barrier (Kunz etal. 1995). 

Many aspects of the degradation of polypeptides are discussed in the reviews of Fontana and Scoffone (125) and of Heinrikson and Kramer (169), while specific experimental procedures are given in the volume of Methods in Enzymology, edited by Hirs (183). A comprehensive presentation of selective chemical cleavage of polypeptide chains can be found in the excellent review of Spande et al. (395). 

Degradation of Polypeptides and Proteins. Elucidation of Organic Structures... 

All known eight-stranded a/p-barrel domains have enzymatic functions that include isomerization of small sugar molecules, oxidation by flavin coenzymes, phosphate transfer, and degradation of sugar polymers. In some of these enzymes the barrel domain comprises the whole subunit of the protein in others the polypeptide chain is longer and forms several additional domains. An enzymatic function in these multidomain subunits, however, is always associated with the barrel domain. 

Chaperones bind to exposed hydrophobic surfaces of polypeptide substrates, and through either ATP-dependent or ATP-independent mechanisms facilitate the folding/assembly, intracellular transport, degradation, and activity of polypeptides. 

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