Protein recombination method

For the purpose of synthesizing flavor peptides or proteins in large scale, we developed "protein recombination method" and "enzymatic synthesis using chemically modified enzyme". "Protein recombination method" was applied to the synthesis of C-terminal portion of p-casein and its analog. Chymotrypsin was chemically modified by Z-DSP in aqueous solution. It was stable for organic solvents. Using this modified enzyme, we succeeded in the synfiiesis of Inverted-Aspartame-Type Sweetener "Ac-Phe-Lys-OH" in one step. 

Today, it is well-known that peptides or proteins exhibit various kinds of taste. Our group has been researching on the relationship between taste and structure of peptides, BPIa (Bitter peptide la, Arg-Gly-Pro-Pro-Phe-Ile-Val) (7 as a bitter peptide, Om-p-Ala-HCl (OBA), Om-Tau-HCl as salty peptides(2j, and "Inverted-Aspartame-Type Sweetener" (Ac-Phe-Lys-OH) as a sweet peptide(5). The relationship between taste and chemical structure was partly made clear. Since commercial demand for these flavor peptides is increasing, we need to develop new synthetic methods which can prepare these peptides in large scale. We developed the following two methods (1) protein recombination method as a chemical method, (2) enzymatic synthesis using chemically modified enzyme as a biochemical method. 

Vaccine candidates are based on the two viral surface proteins, gD and gB (80). Recombinant methods are used to express the proteins, either in Chinese hamster ovary (CHO) cells or in baculovims. The proteins are purified as subunits and formulated with different adjuvants. Clinical trials with these vaccine candidates have been performed, but the results to date have not been encouraging. 

The second example is the SE-HPLC analysis of recombinant hGH. In this example, SE-HPLC is used for both a purity and a protein concentration method for bulk and formulated finished products. This method selectively separates both low molecular weight excipient materials and high molecular weight dimer and aggregate forms of hGH from monomeric hGH, as shown... 

Udit, A.K., Silberg, J.J. and Sieber, V. (2003) Sequence homology-independent protein recombination (SHIPREC). Methods in Molecular Biology (Clifton, NJ), 231, 153-163. 

Derewenda ZS. 2004. The use of recombinant methods and molecular engineering in protein crystallization. Methods 34 354-363. 

Protein Arrays Methods and Protocols, edited by Eric Fung, 2004 263. Flow Cytometry, Second Edition, edited by Teresa S. Hawley and Robert G. Hawley, 2004 262. Genetic Recombination Protocols, edited by Alan S. Waldman, 2004... 

This operation is illustrated by work on the human cytokine GCSF, a protein of 174 residues. The disulfide-linked loop (64-74) of this protein, thought to be involved in binding to the receptor, was replaced by various non-coded synthetic structures.[10] In this case recombinant methods were used to produce a variant of the parent protein having the appropriate cleavage sites for the production of the wanted fragments. 

Flavor notes and products of lipid oxidation in cooked meats, 85,86/ Flavor peptides convenient synthesis, 149-156 enzymatic synthesis, 151,154-156 protein recombination synthetic method, 149... 

Hageman et al. [3.13] calculated the absorption isotherms for recombinant bovine somatotropin (rbSt) and found 5-8 g of water in 100 g of protein, which was not only on the surface but also inside the protein molecule. Costantino et al. [3.72] estimated the water monolayer M0 (g/100 g dry protein) for various pharmaceutical proteins and for their combination with 50 wt% trehalose or mannitol as excipient. They compared three methods of calculating MQ (1) theoretical (th) from the strongly water binding residues, (2) from conventional adsorption isotherm measurements (ai) and (3) from gravimetric sorption analysis (gsa) performed with a microbalance in a humidity-controlled atmosphere. Table 3.5 summarizes the results for three proteins. The methods described can be helpful for evaluating RM data in protein formulations. 

Fenn JB, Mann M, Meng CK Electrospray ionization for mass spectrometry of large biomolecules. Science (1989) 246 64-71. Patrick JS, Lagu AL Review applications of capillary electrophoresis to the analysis of biotechnology-derived therapeutic proteins. Electrophoresis (2001) 22 4179-4196. Sowell J, Salon J, Strekowski L, et al Covalent and noncovalent labeling schemes for near-infrared dyes in capillary electrophoresis protein applications. Methods Mol. Biol. (2004) 276 39-75. Moini M Capillary electrophoresis mass spectrometry and its application to the analysis ofbiological mixtures. Anal. Bio-anal. Chem. (2002) 373 466 180. Nemunaitis J, Holmlund JT, Kraynak M, et al. Phase I evaluation of ISIS 3521, an antisense oligodeoxynucleotide to protein kinase C-a, in patients with advanced cancer./. Clin. Oncol. (1999) 17 3586-3595. De Frutos M, Cifuentes A, Diez-Masa JC Differences in capillary electrophoresis profiles of urinary and recombinant erythropoietin. Electrophoresis (2003) 24 678-680. 

SpA-derived proteins containing different number and composition of domains have been produced by recombinant methods. The binding properties of intact SpA and some SpA-derived protein fragments to IgG, IgA, IgM, and F(ab )2 have been analyzed. The results suggest that the binding is affected both by the number of immunoglobulin binding domains and by the composition of the domains. 

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