title: Stabilized variant of Streptomyces subtilisin inhibitor and its use in stabilizing subtilisin BPN'.
abstract: Protein protease inhibitors could potentially be used to stabilize proteases in commercial products such as liquid laundry detergents. However, many protein protease inhibitors are susceptible to hydrolysis inflicted by the protease. We have engineered Streptomyces subtilisin inhibitor (SSI) to resist proteolysis by adding an interchain disulfide bond and removing a subtilisin cleavage site at leucine 63. When these stabilizing changes were combined with changes to optimize the affinity for subtilisin, the resulting inhibitor provided complete protease stability for at least 5 months at 31 degrees C in a subtilisin-containing liquid laundry detergent and allowed full recovery of the subtilisin activity upon the dilution that occurs in a North American washing machine.
authors.affiliation: Corporate Research Division, Procter & Gamble Co., Miami Valley Laboratories, PO Box 538707, Cincinnati, OH 45253-8707, USA.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Ganz
authors.forename: Mark D
authors.initials: MD
authors.lastname: Bauer
authors.forename: Yiping
authors.initials: Y
authors.lastname: Sun
authors.forename: Angela M
authors.initials: AM
authors.lastname: Fieno
authors.forename: Raymond A
authors.initials: RA
authors.lastname: Grant
authors.forename: Paul E
authors.initials: PE
authors.lastname: Correa
authors.forename: Michael
authors.initials: M
authors.lastname: Laskowski
authors.forename: Charles W
authors.initials: CW
authors.lastname: Saunders
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004269:DNA, Bacterial; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D006868:Hydrolysis; D007930:Leucine / Q000737:chemistry; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D015202:Protein Engineering; D015842:Serine Proteinase Inhibitors / Q000737:chemistry*; D013302:Streptomyces / Q000737:chemistry*; D013381:Subtilisins / Q000037:antagonists & inhibitors*
chemical_list: D004269:DNA, Bacterial; D015842:Serine Proteinase Inhibitors; D013381:Subtilisins; D007930:Leucine