Details

Autor(en) / Beteiligte

• Caporale, Andrea
• Monti, Alessandra
• Selis, Fabio
• Sandomenico, Annamaria
• Tonon, Giancarlo
• Ruvo, Menotti
• Doti, Nunzianna

Titel

A comparative analysis of catalytic activity and stability of microbial transglutaminase in controlled denaturing conditions

Ist Teil von

• Journal of biotechnology, 2019-08, Vol.302, p.48-57

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2019

Quelle

MEDLINE

Beschreibungen/Notizen

• •MTG has structural and functional tolerance to pH changes, whereas it decreases with increasing denaturing agents, such as urea and GdnHCl.•MTG in denaturing conditions shows a higher substrate specificity compared to physiological settings.•Controlled amounts of urea in MTG mediated transamidation reactions improves yield (∼15%) and purity (∼30%) of the final products. Microbial transglutaminases (MTGs) catalyzes the formation of Gln-Lys isopeptide bonds and are widely used for the cross-linking of proteins and peptides in food and in biotechnological applications for bioconjugation reactions. In view of its practical utility, a comparative study of the catalytic activity and stability of the enzyme in a wide range of denaturing conditions has been performed through Circular Dichroism (CD), fluorescence and activity assays performed with model substrates. In agreement with previous results, we show that MTG has a significant structural and functional tolerance to pH changes, whereas the enzyme stability and activity decrease in presence of increasing amounts of denaturing agents, such as urea and guanidinium chloride (GdnHCl). Noteworthy, the activity of MTG in denaturing conditions differs markedly from that in pseudo-physiological settings, shifting unexpectedly toward higher substrate specificity. Also, the use of controlled amounts of denaturing agents (1.0–1.5 M urea) largely improves yields and purity of the final products of 10–15% and 25–30%, respectively. These findings widen the range of applicability of the MTG-mediated biocatalysis for industrial and biotechnological purposes.