1. Refining the Structure of cADPR Rodney Agnant and Dr. Steven M. Graham Harlem Children Society and St. John’s University

2. ♠ Introduction ♠

3. What is cADPR? cADPR – cyclic Adenosine Diphosphate Ribose… … is an organic molecule comprised of carbon, hydrogen, oxygen, nitrogen and phosphorus. … contains both rings and chains that are able to move. … is important for regulating calcium levels in cells; calcium regulates many cellular processes.

4. ♠ Purpose & Hypothesis ♠ Over 100 analogs of cADPR are known. Does the precise structure (better conformation of cADPR determine its function-its ability to cause calcium release? cADPR and its analogs have been characterized structurally only at a low level of sophistication. A thorough structure/function study requires a more rigorous approach to structure.

5. cADPR:North and South Conformations NorthSouth R-ring A-ring R-ring A-ring

6. Two Structure Analysis Programs PSEUROT is a program that calculates H-H (“proton-proton”) angles and ribose ring angles. The input for Pseurot is H-H coupling data obtained from H Nuclear Magnetic Resonance (NMR) Spectroscopy. HyperChem is a program that allows one to create and optimize molecular structures in silico. Hyperchem provides H-H and ribose ring angles that may not be obtainable from ‘H NMR data.

7. ♠ Materials & Procedures ♠

8. HyperChem Procedure Twenty different conformations of cADPR were built and their structures optimized in HyperChem. All  CCC/O and  HCCH were extractd from each structure. The plots of  CCC/O versus  HCCH were constructed

9. PSEUROT Procedure  HCCH = A●  CCC/O + B J HCCH

11. ♠ Results & Conclusion ♠

12. Pseurot-Hyperchem Comparison Pseurot Our Hyperchem Default A,B A,B 1’2’ 1.102, 123.3 1.079 124.4 2’3’ 1.090, 0.2 1.132-2.0 3,4’ 1.095-124.9 1.102-124.3 Output: Output: N(60º) : S(204º) N(68º) : A(210º) 31 : 69 32 : 68

13. Conclusion & Future When comparing results of Hyperchem derived A, B to default and PSEUROT A,B the discrepancy was minimal. We can conclude that Hyperchem can be used to derive the parameters needed for Pseurot Our future goals are to obtain and use molecules unknown to PSEUROT, for example 2’-dA cADPR.

14. ♠ Acknowledgments ♠ Dr. Steven Graham St John’s University Faculty and Staff Dr. Sat Baccharaya Harlem Children Society Staff