Record Details
The urea denaturation of bovine serum albumin, polyglycyl bovine serum albumin and poly-L-phenylalanyl bovine serum albumin
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | The urea denaturation of bovine serum albumin, polyglycyl bovine serum albumin and poly-L-phenylalanyl bovine serum albumin |
| Names |
Chung, Po-luen
(creator) Becker, Robert R. (advisor) |
| Date Issued | 1966-10-31 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | A comparative study was made on the effect of urea denaturation of bovine serum albumin (BSA), polyglycyl BSA and poly-L-phenylalanyl BSA. The denaturation process was followed by ultraviolet spectrophotometry and optical rotation. A blue shift in the absorption maximum at 278 mμ was observed in urea denatured proteins, In 7M urea solution, the peak of the native BSA shifted from 278.4 mμ to 276.7 mμ. However, for urea denatured poly-L-phenylalanyl BSA, the extent of the shift was small, from 278. 5 mμ to 278 mμ. Polyglycyl BSA had the same spectrum as native BSA, and the extent of the shift in 7M urea was about 1.5 mμ. The difference spectra between native proteins and urea denatured proteins were investigated as the functions of molarities of urea from 1 M to 7 M. On exposure of native BSA, polyglycyl BSA and poly-L-phenylalanyl BSA to urea concentrations above 2-3M at pH 7.6, an immediate blue shift in the absorption maximum at 278.5 mμ occurred. The extent of this shift was dependent on the urea concentration. A minimum in molar absorptivity difference (Δε) was also observed at 287 mμ. There was a strong dependency of Δε₂₈₇ on urea concentration for native BSA, polyglycyl BSA and poly-L-phenylalanyl BSA. No significant difference on the effect of urea concentration on Δε₂₈₇ was found between polyglycyl BSA and native BSA. However, poly-L-phenylalanyl BSA showed more stability toward urea denaturation. The increased levorotation of the urea denatured proteins was dependent on the molarities of urea. At pH 7.6 and 7M urea, the specific rotation [α][subscript D] of native BSA changed from -61° to -104° polyglycyl BSA from -58° to -98°, and poly-L-phenylalanyl BSA from -57° to -76°. In pH 5.5, the effect of urea on [α][subscript D] of polyglycyl BSA resembled native BSA. The [α][subscript D] of polyglycyl BSA and native BSA at pH 5.5 changed from -60° to about -105° in 7M urea. The stability of poly-L-phenylalanyl BSA toward urea denaturation was interpreted in terms of the protective effect of sodium dodecyl sulfate against urea denaturation of serum albumin. |
| Genre | Thesis/Dissertation |
| Topic | Serum albumin |
| Identifier | http://hdl.handle.net/1957/47661 |
