Purity ~90% (SDS-PAGE). Calumenin, also known as calumenin isoform a, which is a multiple EF-hand calcium-binding protein located in endoplasmic reticulum(ER) and sarcoplasmic reticulum (SR) of mammalian tissues. This protein binds 7 calcium ions with a low affinity and is involved in such ER functions as protein folding and sorting. Source: Recombinant protein corresponding to aa20-315 from human Calumenin, expressed in E. coli. Molecular Weight: ~35kD (297aa), confirmed by MALDI-TOF AA