Tissue transglutaminase (TG2) catalyzed glutamine deamidation within gluten peptides plays a major role in the pathogenesis of celiac disease. Recent studies reported gliadin deamidation by microbial transglutaminase (MTG) and hypothesize an impact on celiac disease incidence. We therefore investigated deamidation and transamidation activities of MTG and human TG2 based on a wheat gliadin peptide containing an immunodominant epitope for celiac disease. Deamidation activity of MTG was about a magnitude lower than transamidation with a maximum at pH 5 and decreasing values at neutral and basic pH. In contrast, TG2-deamidation reaction rate doubled from pH 6 to pH 7. Transamidation activity of MTG showed minor pH dependence, whereas for TG2 it strongly increased from pH 6 to 7 by a factor of 7.5. Additionally, deamidation by TG2 in the presence of a fivefold excess of amine substrate was observed for reactions at pH 6 at an equal rate to transamidation, while at neutral pH no deamidation occurred. MTG only catalyzed deamidation in addition to transamidation when the substrate ratio was below a 2.5 fold excess of amine. In conclusion, transamidation activity rates of MTG and TG2 were higher compared to deamidation rates. In contrast to TG2, MTG shows a strong and pH-independent transamidation preference.
Journal of Cereal Science – Elsevier
Published: Jul 1, 2016
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.
Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.
It’s easy to organize your research with our built-in tools.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera