Gluten may be harmful, causing disorders such as celiac disease (CD) and non-CD gluten sensitivity. CD has severe manifestations, with ~1% prevalence. There is still no cure for CD. The invention is an acidic peptidease able to remove the toxic peptides derived from gluten under the stomach-like condition. Therefore, the peptidase has potential to be an oral therapeutic enzyme for CD patents.

The oral peptidase used to improve the health condition of celiac disease patients must meet the criteria such as being able to digest the toxic gluten-derived peptides and being functional at <pH 4. The invented peptidase, obtained through bacterial screening and enzyme directed evolution, meets the criteria and is superior to the counterparts described in the literature.

The invented peptidase can be applied in three business models. First, it can be used as a food processing enzyme for the preparation of gluten-free foods. Second, it can be an active ingredient in dietary supplements, used to improve the health of those suffering from gluten ingestion. Third, it can be developed into an oral therapeutic enzyme, used to protect the celiac disease patients.