Crystal structure of the YffB protein from Pseudomonas aeruginosa suggests a glutathione-dependent thiol reductase function

Abstract

Background: The yffB (PA3664) gene of Pseudomonas aeruginosa encodes an uncharacterized protein of 13 kDa molecular weight with a marginal sequence similarity to arsenate reductase from Escherichia coli. The crystal structure determination of YffB was undertaken as part of a structural genomics effort in order to assist with the functional assignment of the protein.

Results: The structure was determined at 1.0 A resolution by single-wavelength anomalous diffraction. The fold is very similar to that of arsenate reductase, which is an extension of the thioredoxin fold.

Conclusion: Given the conservation of the functionally important residues and the ability to bind glutathione, YffB is likely to function as a GSH-dependent thiol reductase.

Figure 1

(Left) Ribbon presentation of the polypeptide fold of YffB. Active site residues are shown as ball-and-stick models (produced with MOLSCRIPT [19]). (Right) Electrostatic surface potential calculated with GRASP [20]. Positive charges are blue and negative are red.