Protein refolding agent and refolding method

Abstract

A refolding agent and refolding method which makes it possible to produce high-purity proteins in high productivity. The refolding agent includes a phosphorus-containing compound (A) and an oxycarbonyl group-containing compound (B). The refolding method includes the step of treating the unfolded protein with the refolding agent. As the compound (A), there may be at least one selected from inorganic phosphoric acids, alkyl phosphate esters, sugar phosphate esters, and salts of these, and as the compound (B), there may be at least one selected from formic acid, acetic acid, propionic acid, lactic acid, tartaric acid, and salts of these.

1 . A refolding agent for an unfolded protein which is a phosphorus-containing refolding agent (C) comprising a compound (A) having a group represented by the formula (1): 
     
       
         
         
             
             
         
       
     
   
   
       2 . The refolding agent according to  claim 1  wherein, in a refolding step, the concentration thereof at a compound (A) concentration, in the system, is 0.2 to 6 moles/L. 
   
   
       3 . The refolding agent according to  claim 1   wherein the compound (A) is at least one species selected from the group consisting of inorganic phosphoric acids, alkyl phosphate esters, sugar phosphate esters, and salts of these.   
   
   
       4 . The refolding agent according to  claims 1  or  2   wherein the compound (A) is at least one species selected from the group consisting of phosphoric acid, pyrophosphoric acid, polyphosphoric acids, adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, and salts of these.   
   
   
       5 - 8 . (canceled) 
   
   
       9 . The refolding agent according to  claims 1  or  2   wherein the unfolded protein has a molecular weight of 1,000 to 300,000.   
   
   
       10 . The refolding agent according to  claims 1  or  2   wherein the unfolded protein is a protein unfolded with guanidine hydrochloride and/or urea.   
   
   
       11 . A method of refolding an unfolded protein
 which comprises the step of treating the unfolded protein with the phosphorus-containing refolding agent (C) according to  claims 1  or  2 ,   wherein, in this step, the concentration thereof at a compound (A) concentration, in the system, is 0.2 to 6 moles/L.   
   
   
       12 . (canceled) 
   
   
       13 . The method according to  claim 11   wherein a surfactant (E) is used in the step of treating with the refolding agent.   
   
   
       14 . The method according to  claim 11   wherein a pH adjusting agent (F) and/or protein stabilizing agent (G) is used in the step of treating with the refolding agent.   
   
   
       15 . The method according to  claim 11   wherein, in the step of treating with the phosphorus-containing refolding agent (C) or the oxycarbonyl group-containing refolding agent (D), the protein concentration in the system is 0.2 to 30 mg/mL.   
   
   
       16 . A method of protein production
 which comprises the step of refolding by the method according to  claim 11 .   
   
   
       17 . A protein obtained by the production method according to  claim 11 .