Alkaline protease produced by a bacillus

Abstract

A novel enzyme having a high proteolytic activity in alkaline media and being suitable for inclusion in washing compositions and which is produced by a novel Bacillus strain designated "PB 92", or its proteolytic enzyme producing mutants or variants. A culture of the Bacillus is deposited with the Laboratory for Microbiology of the Technical University of Delft, The Netherlands, where it has been given number OR-60.

I claim: 
     
       1. A process for the preparation of an enzyme having high proteolytic activity in alkaline media comprising cultivating Bacillus strain PB 92 in a nutrient medium and recovering the formed proteolytic enzyme. 
     
     
       2. The process of claim 1 wherein the nutrient media contains carbon, nitrogen, calcium salts, magnesium salts and trace elements under aerobic conditions. 
     
     
       3. The process of claim 1 wherein the fermentation broth is filtered, the enzyme is precipitated from the filtrate, recovering and drying the precipitate to recover the enzyme. 
     
     
       4. An alkaline protease produced by cultivation of Bacillus nov. sp. PB 92 and characterized by the following properties: a optimal proteolytic activity at a pH value above 12, said activity being measured against denatured hemoglobin according to the Anson method,   b. consisting of at least three proteolytically active components showing a characteristic zymogram following disc electrophoresis as shown in the accompanying figure,   ______________________________________                                    
(c) the two main components having the following amino acid               
composition:                                                              
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              component 1  component 2                                    
Lysine        6            6                                              
Histidine     7            6                                              
Arginine      9            8                                              
Asparetic acid                                                            
              27           28                                             
Threonine     16           16                                             
Serine        30           30                                             
Glutamic acid 15           15                                             
Proline       12           13                                             
Glycine       31           33                                             
Alanine       36           36                                             
Cystine       0            0                                              
Valine        22           22                                             
Methionine    3            3                                              
Isaolcucine   8            9                                              
Leucine       18           18                                             
Tyrosine      7            6                                              
Phenylalanine 2            2                                              
Tryptophan    3            3                                              
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(d) the two main components having the following physical                 
properties                                                                
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isolectric point                                                          
              10.5         10.5                                           
molecular weight                                                          
              25,500       25,500                                         
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       c. showing an improved washing action in perborate containing washing compositions.   
     
     
       5. A washing composition containing an effective amount of the enzyme of claim 4 having a high proteolytic activity in alkaline media. 
     
     
       6. The washing composition of claim 5 also containing a detergent, a water softener, an alkali metal silicate, a weakly alkaline bicarbonate and optionally an alkali metal per borate. 
     
     
       7. A method of cleaning textiles comprising washing textiles in an aqueous solution containing an effective amount of the washing composition of claim 6. .Iadd. 8. A biologically pure culture of the microorganism Bacillus PB 92, said culture being capable of producing an enzyme having high proteolytic activity in alkaline media, when cultivated in a nutrient medium. .Iaddend.