Structure of S35C flavodoxin mutant from Desulfovibrio vulgaris in the semiquinone state.
The crystallographic structure of an engineered flavodoxin mutant from Desulfovibrio vulgaris has been analysed. Site-directed mutagenesis was used to substitute serine 35 with a cysteine to provide a possible covalent linkage. The crystal structure of the semiquinone form of this mutant is similar to the corresponding oxidation state of the wild-type flavodoxin. Analysis of the structural changes reveals the interaction between N(5)H of the flavin and the carbonyl O atom of Gly61 to be critical for modulation of the electrochemical properties of the protein.
Artali
R
R
Institute of Pharmaceutical Chemistry, University of Milano, Italy. roberto.artali@tiscali.it
Marchini
N
N
Meneghetti
F
F
Cavazzini
D
D
Cassetta
A
A
Sassone
C
C
D019943:Amino Acid Substitution; D016227:Benzoquinones / Q000737:chemistry; D018360:Crystallography, X-Ray; D045285:Desulfovibrio desulfuricans / Q000737:chemistry / Q000235:genetics*; D005418:Flavodoxin / Q000737:chemistry* / Q000235:genetics*; D008958:Models, Molecular; D013056:Spectrophotometry, Ultraviolet
D016227:Benzoquinones; D005418:Flavodoxin; C025232:semiquinone radicals