Abstract:
:A thermodynamic framework (UNIQUAC model with temperature dependent parameters) is applied to model the salt-induced protein crystallization equilibrium, i.e., protein solubility. The framework introduces a term for the solubility product describing protein transfer between the liquid and solid phase and a term for the solution behavior describing deviation from ideal solution. Protein solubility is modeled as a function of salt concentration and temperature for a four-component system consisting of a protein, pseudo solvent (water and buffer), cation, and anion (salt). Two different systems, lysozyme with sodium chloride and concanavalin A with ammonium sulfate, are investigated. Comparison of the modeled and experimental protein solubility data results in an average root mean square deviation of 5.8%, demonstrating that the model closely follows the experimental behavior. Model calculations and model parameters are reviewed to examine the model and protein crystallization process.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Agena SM,Pusey ML,Bogle IDdoi
10.1002/(sici)1097-0290(19990720)64:2<144::aid-bitsubject
Has Abstractpub_date
1999-07-20 00:00:00pages
144-50issue
2eissn
0006-3592issn
1097-0290pii
10.1002/(SICI)1097-0290(19990720)64:2<144::AID-BITjournal_volume
64pub_type
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