Title |
Dimethyl sulfoxide reduction by a hyperhermophilic archaeon Thermococcus onnurineus NA1 via a cysteine-cystine redox shuttle |
Author |
Ae Ran Choi1, Min-Sik Kim1, Sung Gyun Kang1,2, and Hyun Sook Lee1,2* |
Address |
1Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan 15627, Republic of Korea, 2Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon 34113, Republic of Korea |
Bibliography |
Journal of Microbiology, 54(1),31-38, 2016,
|
DOI |
10.1007/s12275-016-5574-1
|
Key Words |
DMSO, Thermococcus onnurineus NA1, cysteinecystine
redox shuttle, thioredoxin reductase, protein disulfide
oxidoreductase, extracellular electron mediator |
Abstract |
A variety of microbes grow by respiration with dimethyl sulfoxide
(DMSO) as an electron acceptor, and several distinct
DMSO respiratory systems, consisting of electron carriers
and a terminal DMSO reductase, have been characterized.
The heterotrophic growth of a hyperthermophilic archaeon
Thermococcus onnurineus NA1 was enhanced by the addition
of DMSO, but the archaeon was not capable of reducing
DMSO to DMS directly using a DMSO reductase. Instead, the
archaeon reduced DMSO via a cysteine-cystine redox shuttle
through a mechanism whereby cystine is microbially reduced
to cysteine, which is then reoxidized by DMSO reduction.
A thioredoxin reductase-protein disulfide oxidoreductase
redox couple was identified to have intracellular cystine-reducing
activity, permitting recycle of cysteine. This study presents
the first example of DMSO reduction via an electron
shuttle. Several Thermococcales species also exhibited enhanced
growth coupled with DMSO reduction, probably by
disposing of excess reducing power rather than conserving
energy. |