ConclusionsThe extracellular serine thiol alkaline protease from S. koyan-gensis strain TN650 (STAP) was purified and biochemicallycharacterized. The results revealed that the enzyme was highlystable and active at high temperature and alkaline pH. Comparedto SG-XIV and KERAB proteases, STAP showed high catalytic effi-ciency, better hydrolysis degree, and elevated tolerance to organicsolvents as well as an excellent stability and compatibility witha wide range of commercialized detergents. Overall, the findingsindicate that STAP is endowed with a number of promising prop-erties that might open new opportunities for the synthesis ofnon-aqueous peptides and laundry detergent formulations. Furtherstudies, some of which are currently underway in our laborato-ries, are needed to investigate the structure-function relationshipsof the enzyme using site-directed mutagenesis and 3-D structuremodeling.Acknowledgments