Environmental influences on the particle sizes of purified κ-casein: metal effect
| Autor: | Peter D. Hoagland, Edward D. Wickham, Joseph J. Unruh, Merton L. Groves, Peter H. Cooke, Harold M. Farrell, Thomas F. Kumosinski |
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| Rok vydání: | 1999 |
| Předmět: |
chemistry.chemical_classification
Range (particle radiation) Chromatography Dimer Polymer Applied Microbiology and Biotechnology Divalent law.invention Metal Crystallography chemistry.chemical_compound chemistry Dynamic light scattering law visual_art visual_art.visual_art_medium Particle Electron microscope Food Science |
| Zdroj: | International Dairy Journal. 9:193-199 |
| ISSN: | 0958-6946 |
| Popis: | Kappa-casein as purified from bovine milk exhibits a rather unique disulfide bonding pattern as revealed by SDS-PAGE. The disulfide bonded caseins present, range from dimer to octamer and above and preparations contain about 10% monomer. All of these heterogeneous polymers, however, self-associate into nearly spherical uniform particles with an average radius of 8.9 nm as revealed by negatively stained transmission electron micrographs. Evidence is presented that multivalent cations play a role in the stabilization of these spherical particles. Treatment with EDTA causes disruption of the κ-casein particles and leads to a broader size distribution as judged by electron microscopy, dynamic light scattering and analytical ultracentrifugation. The size and shape of the particles are in accord with earlier proposed 3D models for κ-casein, that actually predicted participation of divalent cations in the structure. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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