Introduction

Hydrostatic pressure has been previously shown to enhance enzymatic hydrolysis by trypsin [1, 2], chymotrypsin and pepsin [3, 4], as well as by Alcalase, Neutrase, Corolase 7089, Corolase PN-L, and papain [5, 6]. In our preliminary experiments we have confirmed the positive effects of pressure and additional benefits of alternating hydrostatic pressure (pressure cycling) for several enzymes including proteinaseK, PNGaseF, Lys-C and lysozyme. Recent publications have demonstrated the advantages of using alternating hydrostatic pressure (Pressure Cycling Technology, PCT) for proteomic sample preparation. We have developed and evaluated a novel sample preparation scheme, in which PCT is used to enhance cell lysis, protein extraction and proteolytic digestion, which are carried out in a single, chemically inert disposable sample container (PCT MicroTube).