Interactions between trypsin and lanthanide ions in aqueous solutions

CHED 863

Angela K. Stone, stone3619@bellsouth.net1, Emanuel A. Waddell, ewaddell@chemistry.uah.edu2, Stephen Shreeves2, and Nsoki Phambu, nphambu@tnstate.edu3. (1) Biology Department, Tennessee State University, 1015-A Crowder Court, Nashville, TN 37211, (2) Chemistry, University of Alabama in Huntsville, MSB 203C, John Wright Drive, Huntsville, AL 35899, (3) Department of Chemistry, Tennessee State University, 3500 John A Merritt Blvd, Nashville, TN 37209
Trypsin, a gastric aspartic protease, is a zymogen-derived protein. The binding of metal ions to trypsin and the effect that metal ions have on the structure and conformation of trypsin is of great interest. Complexes of Gd3+, Nd3+, Eu3+, and Yb3+ ions with trypsin in aqueous solution at different pHs and metal ion concentrations have been investigated using infrared and fluorescence spectroscopes. The infrared spectra show dramatic changes in the position and intensity of the amide I and II bands of trypsin upon metal complexation, which indicates that the protein secondary structure is affected. The fluorescence spectra show that the tertiary structure of trypsin is also affected by the presence of metal ions cited above. The percentages of α-helix, β-sheet and random coil conformations were found to decrease after complexation with metal. Structural changes were also characterized by UV visible, Raman and 1H NMR techniques
 

Undergraduate Research Poster Session: Biochemistry
2:00 PM-4:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008