Biomedica

Spectroscopic and thermodynamic comparisons of Escherichia coli DNA photolyase and Vibrio cholerae cryptochrome 1

Sokolowsky, Kathleen1; Newton, Maire1; Lucero, Carlos2; Wertheim, Bradley1, 3;Freedman, Jaryd1, 4; Cortazar, Frank1, 5; Czochor, Jennifer1, 6; Schelvis, Johannes P. M.2 ; Gindt, Yvonne M.1

Source: Journal of Physical Chemistry B, v 114, n 20, p 7121-7130, May 27, 2010; ISSN:15206106, E-ISSN: 15205207; DOI: 10.1021/jp102275r; Publisher: American Chemical Society

Author affiliations:

1 Department of Chemistry, Hugel Science Center, Lafayette College, Easton, PA18042, United States

2 Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, United States

3 Harvard Medical School, Tosteson Medical Education Center,Cannon Society, 760 Longwood Ave., Boston, MA 02115, United States

4 Temple University, School of Medicine, Medicine Education and Research Building, 3500 N. Broad Street, Philadelphia, PA 19140,United States

5 University of Miami, Miller School of Medicine, Rosensteil Medical Science Building, 1600 NW 10th Ave., Miami, FL 33136, United States

6 Yale University, Biological and BiomedicalSciences, New Haven, CT 06520, United States

Abstract:

Escherichia coli DNA photolyase and cryptochrome 1 isolated from Vibrio cholerae, a member of the CRY-DASH family, are directly comparedusing a variety of experimental methods including UV-vis and Raman spectroscopy, reduction potential measurements, and isothermal titration calorimetry. The semiquinone form of the cryptochrome has anabsorption spectrum that is red-shifted from that of the photolyase, but the Raman spectrum indicates that the FAD binding pocket is similar to that of photolyase. The FADH-/FADH· reduction potentialof the cryptochrome is significantly higher than that of the photolyase at 164 mV vs NHE, but it also increases upon substrate binding (to 195 mV vs NHE), an increase similar to what is observed in...