DsbA
Encyclopedia
DSBA oxidoreductase is sub-family of the Thioredoxin family. The efficient and correct folding of bacterial disulfide bonded proteins in vivo is dependent upon a class of periplasmic oxidoreductase proteins called DsbA, after the Escherichia coli
enzyme. The bacterial protein-folding factor DsbA is the most oxidizing of the thioredoxin
family. DsbA catalyzes disulfide-bond formation during the folding of secreted proteins. The extremely oxidizing nature of DsbA has been proposed to result from either domain motion or stabilizing active-site interactions in the reduced form. DsbA's highly oxidizing nature is a result of hydrogen bond, electrostatic and helix-dipole interactions that favour the thiolate over the disulfide at the active site. In the pathogenic bacterium Vibrio cholerae
, the DsbA homolog (TcpG) is responsible for the folding, maturation and secretion of virulence factors.
Sequence/ Structure Details:. The stucture 3L9S has in total 1 chains. Out of these 1 are sequence-unique. The structure of the crystal is composed of 50% helical (9 helices; 97 residues) and 10% beta sheet (6 strands; 21 residues). The crystal structure of DsbA contains a thioredoxin like fold which includes a central β-strand in the central β-sheet and the insertion of a 65 residue helical domain. These insertions are common within the thioredoxin family.
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
enzyme. The bacterial protein-folding factor DsbA is the most oxidizing of the thioredoxin
Thioredoxin
Thioredoxin is a class of small redox proteins known to be present in all organisms. It plays a role in many important biological processes. In humans, it is encoded by the TXN gene. Loss-of-function mutation of either of the two human thioredoxin genes is lethal at the four-cell stage of the...
family. DsbA catalyzes disulfide-bond formation during the folding of secreted proteins. The extremely oxidizing nature of DsbA has been proposed to result from either domain motion or stabilizing active-site interactions in the reduced form. DsbA's highly oxidizing nature is a result of hydrogen bond, electrostatic and helix-dipole interactions that favour the thiolate over the disulfide at the active site. In the pathogenic bacterium Vibrio cholerae
Vibrio cholerae
Vibrio cholerae is a Gram-negative, comma-shaped bacterium. Some strains of V. cholerae cause the disease cholera. V. cholerae is facultatively anaerobic and has a flagella at one cell pole. V...
, the DsbA homolog (TcpG) is responsible for the folding, maturation and secretion of virulence factors.
Sequence/ Structure Details:. The stucture 3L9S has in total 1 chains. Out of these 1 are sequence-unique. The structure of the crystal is composed of 50% helical (9 helices; 97 residues) and 10% beta sheet (6 strands; 21 residues). The crystal structure of DsbA contains a thioredoxin like fold which includes a central β-strand in the central β-sheet and the insertion of a 65 residue helical domain. These insertions are common within the thioredoxin family.