Designing customized protein-specific-buffer system

Abstract

The present invention is related to the field of protein chemistry. In particular, mixed buffer compositions are formulated that allow an accurate identification of agent-induced changes in protein melting point temperatures. Such buffer compositions provide for methods that determine the specific effects of exogenous agents on protein stability, cryoprotective effects and/or protein quality control (e.g., synthesis and/or extraction purity validations).

I claim: 
     
         1 . A method for designing a customized protein-specific buffer system, comprising:
 a) providing:
 i) a solid substrate comprising a plurality of testing wells and a control well, wherein each of said plurality of testing wells comprises a first buffer and a second buffer and a different test compound, said control well comprises a sample buffer, and each of said plurality of testing wells and control well comprises a protein sample; 
 ii) a thermocycler device configured with an optical reaction module and an optically readable storage medium device; 
   b) inserting said solid substrate into said thermocycler device;   c) cycling said thermocycler device between a first temperature and a second temperature under conditions such that said optical reaction module collects a data file from each of said plurality of testing well series and said control well; and   d) storing said data files on said optically readable storage medium device;   e) processing said data files to select at least one test compound as a component for a customized buffer system for said protein.   
     
     
         2 . The method of  claim 1 , wherein said processing produces a plurality of protein melting point temperature profiles. 
     
     
         3 . The method of  claim 2 , wherein each of said protein melting point temperature profiles comprise an inflection point. 
     
     
         4 . The method of  claim 2 , wherein said selected at least one test compound has a higher inflection point T m  than said control inflection point T m . 
     
     
         5 . The method of  claim 2 , wherein said customized protein-specific buffer system is selected from the group consisting of a customized protein-specific stability buffer system and a customized protein-specific cryoprotection buffer system. 
     
     
         6 . The method of  claim 1 , wherein said first buffer is selected from the group consisting of MES, citrate and cacodylate. 
     
     
         7 . The method of  claim 1 , wherein said second buffer is selected from the group consisting of bis-tris propane, bicine and HEPES. 
     
     
         8 . The method of  claim 1 , wherein said different test compound is ammonium sulphate. 
     
     
         9 . The method of  claim 1 , wherein said different test compound is an amino acid. 
     
     
         10 . The method of  claim 1 , wherein said different test compound is urea. 
     
     
         11 . The method of  claim 1 , wherein said different test compound is glycerol. 
     
     
         12 . The method of  claim 1 , wherein said different test compound is a hydrogen ion. 
     
     
         13 . The method of  claim 1 , wherein said different test compound is a third buffer. 
     
     
         14 . The method of  claim 1 , wherein said different test compound is dimethyl sulfoxide. 
     
     
         15 . The method of  claim 1 , wherein said different test compound is a Hoefmeister Series compound. 
     
     
         16 . The method of  claim 1 , wherein said different test compound is a metal ion. 
     
     
         17 . The method of  claim 1 , wherein said different test compound is ethylene glycol. 
     
     
         18 . The method of  claim 1 , wherein said different test compound is polyethylene glycol 3350. 
     
     
         19 . The method of  claim 1 , wherein said different test compound is erythritol. 
     
     
         20 . The method of  claim 1 , wherein said different test compound is 2-methyl-2,4-pentanediol. 
     
     
         21 . The method of  claim 1 , wherein said different test compound is polyethylene glycol 6000. 
     
     
         22 . The method of  claim 1 , wherein said different test compound is sodium malonate. 
     
     
         23 . The method of  claim 1 , wherein said different test compound is ethanol. 
     
     
         24 . The method of  claim 1 , wherein said different test compound is polyethylene glycol 10,000. 
     
     
         25 . The method of  claim 1 , wherein said different test compound is glycerol. 
     
     
         26 . The method of  claim 1 , wherein said different test compound is xylitol. 
     
     
         27 . The method of  claim 1 , wherein said different test compound is sucrose. 
     
     
         28 . The method of  claim 1 , wherein said different test compound is trehalose dihydrate. 
     
     
         29 . The method of  claim 1 , wherein said different test compound is 1,6 hexanediol. 
     
     
         30 . The method of  claim 1 , wherein said different test compound is sodium chloride. 
     
     
         31 . The method of  claim 13 , wherein said different third buffer is selected from the group consisting of Trizma, HEPES, Pipes, Bicine, Bis-Tris, TES, MOPS, MES, PBS, CAPS, CHES, Bis-Tris Propane and TAPS. 
     
     
         32 . A method for determining protein quality: comprising:
 a) providing;
 i) a solid substrate comprising a plurality of testing wells and a control well, wherein each of said plurality of testing wells are prefilled with a first buffer and a second buffer, and a plurality of testing well series of said plurality of testing wells wherein each well of said plurality of testing well series is prefilled with a different hydrogen ion concentration; and 
 ii) a thermocycler device configured with an optical reaction module and an optically readable storage medium device; 
   b) inserting said solid substrate into said thermocycler device;   c) cycling said thermocycler device between a first temperature and a second temperature under conditions such that the optical reaction module generates a data file from each of said plurality of testing well series and control well;   d) storing said data files on said optically readable storage medium device;   e) processing said data files to produce a plurality of protein melting point temperature profiles;   displaying said protein melting point temperature profiles as a first three dimensional map; and   g) identifying changes in quality of said protein by differences between said first three dimensional map and a control three dimensional map of said protein.   
     
     
         33 . The method of  claim 32 , wherein each well of said plurality of testing well series further comprises a different sodium chloride concentration. 
     
     
         34 . The method of  claim 32 , wherein said first buffer is selected from the group consisting of MES, citrate and cacodylate. 
     
     
         35 . The method of  claim 32 , wherein second buffer is selected from the group consisting of bis-tris propane, bicine and HEPES.