Title of Talk

Perturbing the polypeptide helix: Effect of non-protein aminoacids

 

Abstract

The helix is a common structural element present in proteins.  Our group is probing the design of peptides that fold into helical structures using alpha aminoisobutyric acid (Aib), a natural non protein amino acid.  We have designed sequences using Aib as a promoter of helical folding while attempting to distort the helix using beta alanine, gamma amnobutyric acid and epsilon amino caproic acids in the center of a seven residue peptideBoc- Ala-Leu-Aib-XXX-Ala-Leu-Aib-OMe.  The peptides were studied using high resolution NMR and X-ray crystallography.  The results reveal new insight into the way non-protein aminoacids affect the folding of helices.

 

 

Figure. NMR constrained energy minimized models of the peptides discussed in this talk are shown.  The guest residue color coded in blue is at the center of the peptide Boc- Ala-Leu-Aib-XXX-Ala-Leu-Aib-OMe.  XXX in A-Ala, B- Gly, C- Beta alanine, D- gamma aminobutyric acid and E- epsilon amino caproic acid.

 

This work was done by Ms. Anju Duley and is part of her Ph.D. thesis.

Gurunath Ramanathan, Professor

 

Department of Chemistry, Indian Institute of Technology Kanpur
Kanpur 208016, INIDA

e-mail: gurunath@iitk.ac.in

 

Profile. I did my B.Sc. (H) and M.Sc. in Chemistry from Delhi University.  After my Ph.D. at IISc., Bangalore and post-docs at MIT, Cambridge and Karolinska Institute Stockholm, I joined the Department of Chemistry as an Assistant professor in 2000.  Currently I am a professor in the same department.  I have varied interests and besides the above mention topic – I also work on organic photovoltaics, GFP modeling, biodegradation of environmental pollutants, Enzyme engineering and some theory as well.  My publication list below has been selected to represent this diversity.

 

Selected Publications

1. Jain, V.; Rajbongshi, B. K.; Mallajosyula, A. T.; Bhattacharjya, G.; Iyer, S. K.; Ramanathan, G. Solar Energy Materials and Solar Cells 2008, 92, 1043

2. Swaroop, S.; Sughosh, P.; Ramanathan, G., J. Hazardous Materials 2009, 171, 268

3. Duley, A.; Nethaji, M.; Ramanathan, G, Crystal Growth & Design 2011, 11, 2238

4. Rajbongshi, B. K.; Nair, N. N.; Nethaji, M.; Ramanathan, G. Crystal Growth & Design 2012, 12, 1823

5. Singh D.; Gurunath, R. Biodegradation 2013, 24, 645