Protein main-chain conformation

F. Avbelj and J. Moult. Role of electrostatic screening in determining protein main chain conformational preferences. BiochemAstry, 34 755-764, 1995. 

Structurally important role, by allowing unusual main chain conformations. This may explain why a high proportion of Gly residues in homologous protein sequences are conserved. 

Can H cramps NMR become an effective means for conformational analysis of polypeptides and proteins in the solid state In order to answer this question, in this section, we focus on and discuss a study on correlation between the H chemical shifts and the main-chain conformation (secondary structure) of synthetic polypeptides.Homopolypeptides and copolypeptides are useful as models for structural analysis of natural proteins. Homopolypeptide is the simplest and the most basic model polypeptide for NMR studies of proteins. 

In particular, we can now determine the main-chain conformation of various copolypeptides (and some proteins) in the solid state from the criso and labelled natural protein can be provided. As the relation between the nitrogen shielding and the structures (primary, secondary and higher ordered structures) is clarified in the future, we will be able to get more detailed information on the structure of polypeptides and proteins in the solid state. 

K. Ogata, H. Umeyama. Prediction of protein side-chain conformations by principal component analysis for fixed main-chain atoms. Protein Eng. 1997, 10, 353-359. 

Chakrabarti, R and D. Pal. 2001. The interrelationships of side-chain and main-chain conformations in proteins. Prog Biophys Mol Biol 76 1. 

One protein that yielded to X-ray analysis was silk fibroin. Meyer and Mark were able to calculate the complete unit cell The main chain conformation of collagen was also discovered. Because of the commercial importance of wool, the study of keratin fibers was heavily funded and was also successful. 

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