Download MendeleyAn NMR-derived model for the solution structure of oxidized putidaredoxin, a 2-Fe, 2-S ferredoxin from Pseudomonas.
Pochapsky, T.C., Ye, X.M., Ratnaswamy, G., Lyons, T.A.(1994) Biochemistry 33: 6424-6432
- PubMed: 8204575
- DOI: https://doi.org/10.1021/bi00187a006
- Primary Citation of Related Structures:
1PUT - PubMed Abstract:
A model for the solution structure of oxidized putidaredoxin (Pdx), a 106-residue globular protein containing a Fe2S2 cluster, has been determined using homonuclear NMR methods. Pdx is the first of the class of Fe2S2Cys4 ferredoxins which act as electron-transfer partners for P-450 monooxygenases to be structurally characterized, and no crystal structure has been determined for Pdx or for any closely homologous protein. Pdx is the physiological redox partner of cytochrome P-450cam. A total of 878 NOE distance constraints, 66 phi angular constraints derived from NH-C alpha H coupling constants, and five paramagnetic broadening constraints were used in simulated annealing structural refinements to obtain a family of structures with pairwise rms deviations of 1.14 A for backbone atoms and 1.80 A for all non-hydrogen atoms. Paramagnetic broadening of resonances within a ca. 8-A radius of the metal cluster prevents the use of NMR-derived constraints in this region of the protein; structural constraints used to model the environment of the metal cluster were obtained from site-directed mutagenesis and model compounds and by comparison with known ferredoxin structures. Pdx retains a similar folding topology to other structurally characterized Fe2S2Cys4 ferredoxins but differs from the other ferredoxins in containing a significantly more compact structure in the C-terminal half of the protein.
Organizational Affiliation:
Department of Chemistry, Brandeis University, Waltham, Massachusetts 02254-9110.
