P-21
A catalog product label whose identity is unconfirmed; it overlaps with the well-known p21 cell-cycle protein but matches no documented peptide.
Overview
P-21 appears in this catalog as a single product label within a metabolic-energy grouping. The identifier overlaps with p21, a well-characterized cyclin-dependent kinase inhibitor protein involved in cell-cycle control, but no distinct P-21 peptide with peer-reviewed documentation matching this listing could be identified. Its identity, composition, and research status are therefore unconfirmed, and mechanistic or dosing claims attached to the label should be regarded as vendor-generated.