Andrew Wittman
Biology 152
Lab Section 409
3/23/2015
PURIFICATION OF SPERM WHALE APOMYOGLOBIN AND THE ORIGIN OF ITS HELICAL FOLD
Abstract
The purpose of this research is to understand how secondary structures of a protein, in this case sperm whale apomyoglobin, affect the denatured state of that protein. The scientific community has been working under the impression that once denatured by urea, a protein loses all of its secondary structure. In this research the effect that apomyoglobin’s history of secondary structure has on the denatured state of the protein will be determined through kinetics of the refolding reaction. The kinetics of the refolding of apomyoglobin that has been denatured from a predominantly alpha helical structure will be compared to the kinetics of the refolding of apomyoglobin that has been denatured from a predominantly beta sheet structure.
Introduction Anfinsen (1973) found that proteins have the capacity unfold from their native state into a denatured form, and then refold back into their native state through a reversible process. A protein that has been denatured by urea …show more content…
Unlike its related holoprotien, myoglobin, Apomyoglobin lacks a heme group within the molecule. This allows the kinetics of refolding to be unimolecular. (Jennings and Wright 1993) In this study, differences in the refolding of proteins with a history of beta sheet will be compared to proteins with a history of alpha helices. Apomyoglobin will be able to provide both structures; Its native state apomyoglobin is dominated by alpha helices (Tusi et al. 1999) and, like most proteins, the secondary structure of apomyoglobin can be altered from a predominantly alpha helical structure to a predominantly beta sheeted structure through heat treatment. The temperature required for this change in structure to occur is about 90 degrees Celsius. (Correa and Ramos
Biology 152
Lab Section 409
3/23/2015
PURIFICATION OF SPERM WHALE APOMYOGLOBIN AND THE ORIGIN OF ITS HELICAL FOLD
Abstract
The purpose of this research is to understand how secondary structures of a protein, in this case sperm whale apomyoglobin, affect the denatured state of that protein. The scientific community has been working under the impression that once denatured by urea, a protein loses all of its secondary structure. In this research the effect that apomyoglobin’s history of secondary structure has on the denatured state of the protein will be determined through kinetics of the refolding reaction. The kinetics of the refolding of apomyoglobin that has been denatured from a predominantly alpha helical structure will be compared to the kinetics of the refolding of apomyoglobin that has been denatured from a predominantly beta sheet structure.
Introduction Anfinsen (1973) found that proteins have the capacity unfold from their native state into a denatured form, and then refold back into their native state through a reversible process. A protein that has been denatured by urea …show more content…
Unlike its related holoprotien, myoglobin, Apomyoglobin lacks a heme group within the molecule. This allows the kinetics of refolding to be unimolecular. (Jennings and Wright 1993) In this study, differences in the refolding of proteins with a history of beta sheet will be compared to proteins with a history of alpha helices. Apomyoglobin will be able to provide both structures; Its native state apomyoglobin is dominated by alpha helices (Tusi et al. 1999) and, like most proteins, the secondary structure of apomyoglobin can be altered from a predominantly alpha helical structure to a predominantly beta sheeted structure through heat treatment. The temperature required for this change in structure to occur is about 90 degrees Celsius. (Correa and Ramos