Protein transglutaminase catalyzed

These transglutaminase-catalysed reactions can be nsed to modify the functional properties of food proteins. Transglutaminase has been nsed to catalyze the cross-hnking of a nnmber of proteins, such as whey proteins, soy proteins, glnten, myosin and... 

Since application of microbial transglutaminase-catalyzed modification on food proteins is vast, intense attention must be focused on nutritional efficiency of such cross-linked proteins. It has been demonstrated that the glutamine-lysine dipeptide could be metabolized in rats, and that lysine was... 

Colas, B., Caer, D., and Fournier, E., Transglutaminase catalyzed glycosylation in vegetable protein effect on solubility of pea legumin and wheat ghadins, J. Agric. Food Chem., 41, 1811, 1993. 

Figure 7 shows the SDS-PAGE profile of protein conjugates produced by transglutaminase-catalyzed crosslinking. Lanes 1 and 2 indicate that caseins (both a-casein and P-casein) are good substrates for transglutaminase. Almost... 

Tanaka T, Kamiya N, Nagamune T (2005) N-Terminal glycine-specific protein conjugation catalyzed by microbial transglutaminase. FEBS Lett 579 2092-2096... 

Lin CW, Ting AY (2006) Transglutaminase-catalyzed site-specific conjugation of small-molecule probes to proteins in vitro and on the surface of living cells. J Am Chem Soc 128 4542- 543... 

The most important reaction in blood clotting is the conversion, catalyzed by thrombin, of the soluble plasma protein fibrinogen (factor 1) into polymeric fibrin, which is deposited as a fibrous network in the primary thrombus. Thrombin (factor 11a) is a serine proteinase (see p. 176) that cleaves small peptides from fibrinogen. This exposes binding sites that spontaneously allow the fibrin molecules to aggregate into polymers. Subsequent covalent cross-linking of fibrin by a transglutaminase (factor Xlll) further stabilizes the thrombus. 

In vitro, the enzyme is able to catalyze crosslinking of whey proteins, soy proteins, wheat proteins, beef myosin, casein, and crude actomyosin (which is refined from mechanically deboned meat), improving functional properties such as the texture of food products [49-53], Bonds formed by transglutaminase exhibit a high resistance to proteolytic degradation [54],... 

Another biologically compatible, site-specific method for poly(ethylene glycol) (PEG) conjugation to proteins was described by Sato (2002), who reported the use of the transglutaminase enzyme to catalyze the acyl transfer between the y-carboxyamide group of glutamine and alkylamines under mild conditions. This method could easily be adopted for peptide-PEG conjugation. 

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. 

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