Factors affecting the solubility of Bacillus halmapalus α-amylase
| Autor: | Svend Kaasgaard, Jørgen Mollerup, Timothy John Hobley, Cornelius Faber, Owen R.T. Thomas |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
chemistry.chemical_classification
Hofmeister series Process Chemistry and Technology General Chemical Engineering Sodium Inorganic chemistry Energy Engineering and Power Technology chemistry.chemical_element Salt (chemistry) General Chemistry Industrial and Manufacturing Engineering law.invention chemistry.chemical_compound chemistry law Zeta potential Lithium Lysozyme Solubility Crystallization |
| Zdroj: | Chemical Engineering and Processing: Process Intensification. 47:1007-1017 |
| ISSN: | 0255-2701 |
| DOI: | 10.1016/j.cep.2007.02.015 |
| Popis: | A detailed study of the solubility of recombinant Bacillus halmapalus α-amylase has been conducted. A semi-purified preparation from a bulk crystallisation was chos en that contained six isoforms with p I -values of between 5.5 and 6.1. The solubility was strongly affected by pH and could be reduced approximately 200-fold at pH 6 as compared to pH 10, leaving only 0.1 mg/mL in solution. Solubility could also be dramatically manipulated using salts. The choice of anions was found to be more important than of the cations, and the lowest solubility was found using sodium sulphate. For the anions, solubility followed the order expected from the Hofmeister series, however, a more complex behaviour was seen for the cations. With the exception of lithium, their efficiency to influence the solubility was reversed to what was expected. The polydispersity of the solution was reduced by salt addition and zeta potential measurements indicated a shift in p I caused by lithium. Possible explanations for the observations are discussed, extending our present understanding of how salts affect the solubility of proteins, one that to date is primarily based on experiments with lysozyme. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect