Disulfide bond formation by exported glutaredoxin indicates glutathione's presence in the E. coli periplasm

Markus Eser, Lluis Masip, Hiroshi Kadokura, George Georgiou, Jonathan Beckwith

Research output: Contribution to journalArticlepeer-review

44 Citations (Scopus)

Abstract

Organisms have evolved elaborate systems that ensure the homeostasis of the thiol redox environment in their intracellular compartments. In Escherichia coli, the cytoplasm is kept under reducing conditions by the thioredoxins with the help of thioredoxin reductase and the glutaredoxins with the small molecule glutathione and glutathione reductase. As a result, disulfide bonds are constantly resolved in this compartment. In contrast to the cytoplasm, the periplasm of E. coli is maintained in an oxidized state by DsbA, which is recycled by DsbB. Thioredoxin 1, when exported to the periplasm turns from a disulfide bond reductase to an oxidase that, like DsbA, is dependent on DsbB. In this study we set out to investigate whether a subclass of the thioredoxin superfamily, the glutaredoxins, can become disulfide bond-formation catalysts when they are exported to the periplasm. We find that glutaredoxins can promote disulfide bond formation in the periplasm. However, contrary to the behavior of thioredoxin 1 in this environment, the glutaredoxins do so independently of DsbB. Furthermore, we show that glutaredoxin 3 requires the glutathi- one biosynthesis pathway for its function and can oxidize substrates with only a single active-site cysteine. Our data provides in vivo evidence suggesting that oxidized glutathione is present in the E. coli periplasm in biologically significant concentrations.

Original languageEnglish
Pages (from-to)1572-1577
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume106
Issue number5
DOIs
Publication statusPublished - 2009 Feb 3
Externally publishedYes

Keywords

  • Monothiol
  • Protein oxidation
  • SRP

ASJC Scopus subject areas

  • General

Fingerprint

Dive into the research topics of 'Disulfide bond formation by exported glutaredoxin indicates glutathione's presence in the E. coli periplasm'. Together they form a unique fingerprint.

Cite this