Pressure-induced dissociation of casein micelles: size distribution and effect of temperature
Pressure-induced dissociation of a turbid solution of casein micelles was studied in situ in static and dynamic light scattering experiments. We show that at high pressure casein micelles decompose into small fragments comparable in size to casein monomers. At intermediate pressure we observe partic...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Associação Brasileira de Divulgação Científica
2005-08-01
|
| Series: | Brazilian Journal of Medical and Biological Research |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2005000800008 |
| _version_ | 1818148741416222720 |
|---|---|
| author | R. Gebhardt W. Doster U. Kulozik |
| author_facet | R. Gebhardt W. Doster U. Kulozik |
| author_sort | R. Gebhardt |
| collection | DOAJ |
| description | Pressure-induced dissociation of a turbid solution of casein micelles was studied in situ in static and dynamic light scattering experiments. We show that at high pressure casein micelles decompose into small fragments comparable in size to casein monomers. At intermediate pressure we observe particles measuring 15 to 20 nm in diameter. The stability against pressure dissociation increased with temperature, suggesting enhanced hydrophobic contacts. The pressure transition curves are biphasic, compatible with a temperature (but not pressure)-dependent conformational equilibrium of two micelle species. Our thermodynamic model predicts an increase in structural entropy with temperature. |
| first_indexed | 2024-12-11T12:55:58Z |
| format | Article |
| id | doaj.art-7ab287fa7c7146988c9c9f4d87f8e415 |
| institution | Directory Open Access Journal |
| issn | 0100-879X 1414-431X |
| language | English |
| last_indexed | 2024-12-11T12:55:58Z |
| publishDate | 2005-08-01 |
| publisher | Associação Brasileira de Divulgação Científica |
| record_format | Article |
| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-7ab287fa7c7146988c9c9f4d87f8e4152022-12-22T01:06:35ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research0100-879X1414-431X2005-08-013881209121410.1590/S0100-879X2005000800008Pressure-induced dissociation of casein micelles: size distribution and effect of temperatureR. GebhardtW. DosterU. KulozikPressure-induced dissociation of a turbid solution of casein micelles was studied in situ in static and dynamic light scattering experiments. We show that at high pressure casein micelles decompose into small fragments comparable in size to casein monomers. At intermediate pressure we observe particles measuring 15 to 20 nm in diameter. The stability against pressure dissociation increased with temperature, suggesting enhanced hydrophobic contacts. The pressure transition curves are biphasic, compatible with a temperature (but not pressure)-dependent conformational equilibrium of two micelle species. Our thermodynamic model predicts an increase in structural entropy with temperature.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2005000800008Casein micellesHigh-pressure light scatteringPressure dissociation |
| spellingShingle | R. Gebhardt W. Doster U. Kulozik Pressure-induced dissociation of casein micelles: size distribution and effect of temperature Brazilian Journal of Medical and Biological Research Casein micelles High-pressure light scattering Pressure dissociation |
| title | Pressure-induced dissociation of casein micelles: size distribution and effect of temperature |
| title_full | Pressure-induced dissociation of casein micelles: size distribution and effect of temperature |
| title_fullStr | Pressure-induced dissociation of casein micelles: size distribution and effect of temperature |
| title_full_unstemmed | Pressure-induced dissociation of casein micelles: size distribution and effect of temperature |
| title_short | Pressure-induced dissociation of casein micelles: size distribution and effect of temperature |
| title_sort | pressure induced dissociation of casein micelles size distribution and effect of temperature |
| topic | Casein micelles High-pressure light scattering Pressure dissociation |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2005000800008 |
| work_keys_str_mv | AT rgebhardt pressureinduceddissociationofcaseinmicellessizedistributionandeffectoftemperature AT wdoster pressureinduceddissociationofcaseinmicellessizedistributionandeffectoftemperature AT ukulozik pressureinduceddissociationofcaseinmicellessizedistributionandeffectoftemperature |