Open AccessAnaerobic Respiration Using Fe 3+ , S 0 , and H 2 in the Chemolithoautotrophic Bacterium Acidithiobacillus ferrooxidans
Author(s) -
Naoya Ohmura,
Kazuhiro Sasaki,
Norio Matsumoto,
Hiroshi Saiki
Publication year - 2002
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.184.8.2081-2087.2002
Subject(s) - electron acceptor , cytochrome , anaerobic respiration , bacteria , respiration , anaerobic exercise , biology , cytochrome c , cellular respiration , sulfur , electron transport chain , anaerobic bacteria , electron donor , nuclear chemistry , biochemistry , chemistry , mitochondrion , catalysis , organic chemistry , enzyme , botany , physiology , genetics
The chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans has been known as an aerobe that respires on iron and sulfur. Here we show that the bacterium could chemolithoautotrophically grow not only on H(2)/O(2) under aerobic conditions but also on H(2)/Fe(3+), H(2)/S(0), or S(0)/Fe(3+) under anaerobic conditions. Anaerobic respiration using Fe(3+) or S(0) as an electron acceptor and H(2) or S(0) as an electron donor serves as a primary energy source of the bacterium. Anaerobic respiration based on reduction of Fe(3+) induced the bacterium to synthesize significant amounts of a c-type cytochrome that was purified as an acid-stable and soluble 28-kDa monomer. The purified cytochrome in the oxidized form was reduced in the presence of the crude extract, and the reduced cytochrome was reoxidized by Fe(3+). Respiration based on reduction of Fe(3+) coupled to oxidation of a c-type cytochrome may be involved in the primary mechanism of energy production in the bacterium on anaerobic iron respiration.