Over expression of foldases and chaperones improves protein production

Abstract

The present teachings provide methods for increasing protein secretion, e.g., chymosin in filamentous fungi by co-expressing certain chaperone(s) and/or foldase(s). The present teachings also provide filamentous fungi containing certain chaperone(s) and/or foldase(s) and a protein of interest for increased secretion.

1 . A method for production of a secretable polypeptide in a filamentous fungal host comprising:
 expressing a secretion enhancing protein in a filamentous fungal host containing a secretable polypeptide, wherein the secretion enhancing protein is bip1 and the secretable polypeptide is a chymosin.   
     
     
         2 . The method of  claim 1 , comprising expressing at least two secretion enhancing proteins. 
     
     
         3 . The method of  claim 1 , further comprising expressing a second chaperone protein and/or a foldase. 
     
     
         4 . The method of  claim 1 , wherein the filamentous fungal host is  T. reesei.    
     
     
         5 . The method of  claim 1 , wherein the filamentous fungal host is selected from:  Aspergillus, Acremonium, Aureobasidium, Beauveria, Cephalosporium, Ceriporiopsis, Chaetomium paecilomyces, Chrysosporium, Claviceps, Cochiobolus, Cryptococcus, Cyathus, Endothia, Endothia mucor, Fusarium, Gilocladium, Humicola, Magnaporthe, Myceliophthora, Myrothecium, Mucor, Neurospora, Phanerochaete, Podospora, Paecilomyces, Penicillium, Pyricularia, Rhizomucor, Rhizopus, Schizophylum, Stagonospora, Talaromyces, Trichoderma, Thermomyces, Thermoascus, Thielavia, Tolypocladium, Trichophyton, Trametes , and  Pleurotus.    
     
     
         6 . The method of  claim 1 , wherein the chymosin is a bovine chymosin. 
     
     
         7 . The method of  claim 1 , wherein the chymosin is expressed through a promoter of the filamentous fungal host. 
     
     
         8 . The method of  claim 1 , wherein the chymosin is expressed under a cbh1 promoter in  T. reesei.    
     
     
         9 . The method of  claim 1 , wherein the chymosin is produced as a fusion protein. 
     
     
         10 . The method of  claim 1 , wherein the chymosin is produced as a fusion protein with a CBHI, or a portion thereof. 
     
     
         11 . The method of  claim 1 , wherein the chymosin is produced as a fusion protein with a CBHI, or a portion thereof, and the CBHI amino acid sequence is altered to reduce or eliminate catalytic activity. 
     
     
         12 . The method of  claim 1  further comprising inoculating a suitable growth medium with the host and incubating under conditions permitting growth of the host. 
     
     
         13 - 25 . (canceled) 
     
     
         26 . A supernatant obtained using the method of  claim 1 , wherein the supernatant contains substantial amount of chymosin, but not substantial amount of the filamentous fungus.