Cross-link between protein and

It is also known that formaldehyde can form cross links between protein and DNA in vivo. 

Figure 3 Proposed structure for diphenol mediated cross-link between protein and chitin in M. sexta pupal cuticle (from Schaefer et al. 24).

Fraenkel-Conrat H, Olcott HS. The reaction of formaldehyde with proteins. V. Cross-linking between amino and primary amide or guanidyl groups. J. Am. Chem. Soc. 1948 70 2673-2684. 

Armstrong attributed the increased resistance of dentin matrix to proteolysis to the blockage of susceptible sites by covalently bound carbohydrate. Later it became clear that the Maillard reaction induces the formation of covalent bonds (cross-links) between protein molecules, accounting for such resistance as well. The presence of non-degradable matrix proteins inhibits mineral dissolution (Chapter 2). In addition, both brown pigments and cross-linked proteins inhibit the production of extracellular polysaccharides by cariogenic streptococci (Kobayashi et al., 1990). 

Kulcharyk PA, Heinecke JW (2001) Hypochlorous Acid Produced by the Myeloperoxidase System of Human Phagocytes Induces Covalent Cross-Links Between DNA and Protein. Biochemistry 40 3648... 

Simic M, Dizdaroglu M (1985) Formation of radiation-induced cross-links between thymine and tyrosine Possible model for cross-linking of DNA and proteins by ionizing radiation. Biochemistry 24 234-236... 

Piber, M., Koehler, P. 2005. Identification of dehydro-ferulic acid-tyrosine in rye and wheat Evidence for a covalent cross-link between arabinoxylans and proteins. J Agric Food Chem 53 5276-5284. 

With time, the increased glucose concentration leads to glycosylation of the proteins over Amadori products to advanced glycosylation products (AGEs) and cross-linking between proteins. This degenerative process leads to the so-called late diabetic complications (LDC) after some decades. The four main complications are ... 

Transglutaminase (EC2.3.2.13) catalyzes an acyl-transfer reaction and this results in the formation of cross-links between glutamine and lysine residues. The introduction of new cross-links has important consequences for the functionality of proteins. Many aspects have been covered in a review on the use of transglutaminase in milks and dairy products, which show that it can be used to improve various functional properties (Jaros et al., 2006). Selected aspects are highlighted below. 

As the Maillard reaction progresses, there can be cross-linking between protein species and the formation of polymeric species. The formation of these species is expected to further modify the viscosity and gelation properties of the proteins. 

Borrega R., Tribet C., Audebert R. Reversible gelation in hydrophobic poly-electrolyte/protein mixtures an example of cross-links between soft and hard colloids. Macromolecules 1999 32(23) 7798-7806. 

The isolation of this adduct suggests that mitomycin C will form cross-links between DNA and the nucleophilic residues of a DNA binding protein. The formation of these proposed DNA-protein cross-links could be partly responsible for the ability of mitomycin to inhibit DNA synthesis. Molecular mechanics simulations on covalent complexes between left handed helical... 

Toyokuni, S. et al.. Treatment of Wistar rats with a renal carcinogen, ferric nitrilotriacetate, causes DNA-protein cross-linking between thymine and tyrosine in their renal chromatin, Int J. Cancer, 62 (3), 309, 1995. 

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