Proline rich protein

Proline-rich proteins (PRPs) is a class of intrinsically unstructured proteins (IUP) containing several repeats of a short proline-rich sequence.

Many tannin-consuming animals secrete a tannin-binding protein (mucin) in their saliva. Tannin-binding capacity of salivary mucin is directly related to its proline content. Advantages in using salivary proline-rich proteins (PRPs) to inactivate tannins are :

Example of this class of protein is IB5, a human parotid salivary protein known to bind with polyphenols (binding responsible for the astringency mouth feel).

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