The Plant Total Protein Extraction Kit is designed specifically for use in plant bioscience to extract a qualitative sample of all proteins from any type of plant species or tissue. The protocol does not require any ultracentrifugation or aqueous polymer two-phase partitioning (APTP). The kit includes two reagents a plant specific protease inhibitor cocktail and a new chaotropic reagent with increased solubilizing power to extract more hydrophobic proteins (C0356 Protein Extraction Reagent Type 4). Routine use of the reagent in sequential protein extraction of a plant tissue sample with fresh reagent removes nearly all protein from the tissue. The protease inhibitor cocktail is a mixture of protease inhibitors with broad specificity for the inhibition of serine cysteine metalloproteases aspartic and aminopeptidases. It contains pepstatin A 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSf) E-64 leupeptin 1 10-phenanthroline and bestatin. The cocktail has been demonstrated to be