October 2, 2012
Circular Dichroism and Secondary Structure of Proteins
Proteins are vital to an organism life; they are involved in nearly all cellular functions. It is an essential part of enzymes, the cellular membrane, active transport, protein synthesis and wound healing. Because one relies so heavily upon proteins and its function the structure of proteins is also very important. “The way a protein will fold over its self-determines how it interacts with other chemicals in its proximity, primarily because of different attractive forces being subjected at specific angles from certain amino acids on the protein’s primary structure and the final shape in the tertiary and quandary structure (Circular dichroism ).” The structure of proteins can range from simple to complex molecules. Proteins may consist of a primary, secondary, tertiary, and quaternary structure. The secondary structure consists of hydrogen bonds which join amide and carboxyl groups. These bonds aren’t far from the backbone of proteins. This structure is capable of structures such as alpha helicies, beta sheets, and beta turns (Jim, 2007). The physical, secondary structure is important because it helps in determining the activity of a protein. Circular Dichrosim spectroscopy has been identified as prevalent application used in structural biology in determining whether a protein is folded, characterizing its secondary structure, tertiary structure, and the structural family along with other uses as well (Circular dichroism ). Circular dichroism, CD spectroscopy has defined a form of light absorption spectroscopy. It measures the difference in the absorption of circular polarized light by a substance on the right and left. The secondary structure of a protein can be analyzed between the spectrum of approximately 260 and 180 nm. Estimates of secondary proteins can be compared to X-ray crystallography or NMR (Kelly, Jess, & C., 2005).The structures identified...
Cited: Berndt, K. D. (1996, May 31). 4.2.1 Circular dichroism spectroscopy. Retrieved October 02, 2012, from 4.2.1 Circular dichroism spectroscopy
Circular dichroism . (n.d.). Retrieved October 02, 2012, from APlab: http://www.ap-lab.com/circular_dichroism.htm
Jim, C. (2007, August). The Structure of Proteins. Retrieved October 02, 2012, from Chemguide: http://www.chemguide.co.uk/organicprops/aminoacids/proteinstruct.html
Kelly, S. M., Jess, T. J., & C., P. N. (2005). How to study proteins by circular dichroism. Biochimica et Biophysica Acta 1751, 119 – 139.
PARTHASARATHY, M. (1985). Protein secondary structure from circular dichroism spectra. Proc. Int. Symp. Biomol. Struct. Interactions, 141-149.
Whitmore, L., & A., W. B. (2007). Protein Secondary Structure Analyses from Circular Dichroism. Biopolymers, 392-400.
Please join StudyMode to read the full document