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| Author(s): |
Letícia Célia de Lencastre Novaes
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) |
| Defense date: | 2009-09-18 |
| Examining board members: |
Thereza Christina Vessoni Penna;
Daniela de Borba Gurpilhares;
Marco Antônio Stephano
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| Advisor: | Thereza Christina Vessoni Penna |
| Abstract | |
The addition of hydrosoluble excipients, such as, sugars, surfactants, salts and polymers is a common practice in the intent of stabilization of proteins during heating. Several polymers have been used to proteins stabilization, being their effect dependent of protein characteristics, however in some cases, it could cause a reduction of stability. Salts can stabilize proteins, or have no influence in their stability, and these behaviors depend on the type, concentration, ionic interaction and charged protein residues. Thermal stability of green protein fluorescent (GFP) have been demonstrated to humid heat, elevated temperatures (T ≥ 95°C), alkaline pH and to some chemical agents. Its thermal denaturation is highly reproducible and the variation of fluorescence intensity can be easily determinate by spectrofluorometry. The objective of this work was study the behavior of GFP in the presence of different aqueous solutions of polymers (polyethylene glycol, DEAE-Dextran and acid polyacrylic) and salts (citrate and phosphate). From the results, it may be concluded that the citrate favored the preservation of native structure of GFP in the temperatures studied (70ºC to 95ºC), in concentrations above 10% m/m. The PAA polymer also favored the GFP thermal stability, but in a minor intensity and in concentrations above 20% m/m. (AU) | |
| FAPESP's process: | 08/01702-0 - Effect of polymers and salts in the stability of green fluorescent protein GFP |
| Grantee: | Letícia Celia de Lencastre Novaes |
| Support Opportunities: | Scholarships in Brazil - Master |