Crystal Structure of Elastase (IMAGE) Kansas State University Caption This drawing represents the crystal structure of the NSP neutrophil elastase, shown in blue, bound to the Staphylococcus aureus Eap protein, EapH1, shown in gold. Two Kansas State University biochemists have discovered that S. aureus secretes a family of proteins that prevent neutrophil serine proteases, or NSPs, from functioning -- an important finding for understanding how infections are established. Credit Kansas State University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.