A Cambialistic SOD in a Strictly Aerobic Hyperthermophilic Archaeon, Aeropyrum pernix

Yamano, Shigeyuki; Sako, Yoshihiko; Nomura, Norimichi; Maruyama, Tadashi

doi:10.1093/oxfordjournals.jbchem.a022426

Cited by 43 publications

(42 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both enzymes displayed relatively strong resistance against azide (Mnand Fe-SOD activity decreased 50% with 380 and 340 mM azide, respectively). This resistance against azide has also been observed in other archaeal SODs (44,45).…”

Section: Resultssupporting

confidence: 71%

“…However, it has previously been reported that SODs from Sulfolobus, although displaying similarly small molecular masses in gel filtration experiments (11,24), are actually composed of tightly packed tetramers (25,41). Since other SODs from hyperthermophilic archaea also exhibit the same tendency (42,45), this may also be the case for SOD Pc .…”

Section: Discussionmentioning

confidence: 92%

“…Although Mn-and Fe-SODs generally exhibit a strict metal specificity for SOD activity (34), several cambialistic SODs, which are active with either Mn or Fe, have been reported. This is the case in the enzymes from Pyrobaculum aerophilum (42) and Aeropyrum pernix (45). At present, Cu/Zn-SODs have not been found in archaea.…”

mentioning

confidence: 95%

See 2 more Smart Citations

Biochemical Properties and Regulated Gene Expression of the Superoxide Dismutase from the Facultatively Aerobic Hyperthermophile Pyrobaculum calidifontis

2003

View full text Add to dashboard Cite

Superoxide dismutase (SOD) was purified from a facultatively aerobic hyperthermophilic archaeon, Pyrobaculum calidifontis VA1. The purified native protein from aerobically grown cells exhibited 1,960 U of SOD activity/mg and contained 0.86 ؎ 0.04 manganese and <0.01 iron atoms per subunit. The gene encoding SOD was cloned and expressed in Escherichia coli. Although the recombinant protein was soluble, little activity was observed due to the lack of metal incorporation. Reconstitution of the enzyme by heat treatment with either Mn or Fe yielded a highly active protein with specific activities of 1,970 and 434 U/mg, respectively. This indicated that the SOD from P. calidifontis was a cambialistic SOD with a preference toward Mn in terms of activity. Interestingly, reconstitution experiments in vitro indicated a higher tendency of the enzyme to incorporate Fe than Mn. When P. calidifontis was grown under anaerobic conditions, a majority of the native SOD was incorporated with Fe, indicating the cambialistic property of this enzyme in vivo. We further examined the expression levels of SOD and a previously characterized Mn catalase from this strain in the presence or absence of oxygen. Northern blot, Western blot, and activity measurement analyses revealed that both genes are expressed at much higher levels under aerobic conditions. We also detected a rapid response in the biosynthesis of these enzymes once the cells were exposed to oxygen.

show abstract

Section: Resultssupporting

confidence: 71%

Section: Discussionmentioning

confidence: 92%

See 1 more Smart Citation

Biochemical Properties and Regulated Gene Expression of the Superoxide Dismutase from the Facultatively Aerobic Hyperthermophile Pyrobaculum calidifontis

2003

View full text Add to dashboard Cite

show abstract

“…Thermostable SODs are potentially very useful due to their high stability. It has been reported that SODs were isolated from hyperthermophilic organisms, [4][5][6][7][8][9][10] but reports about SODs from thermophilic fungi are few. The thermophilic fungus T. aurantiacus var.…”

mentioning

confidence: 99%

Purification, Characterization, and Molecular Cloning of a Thermostable Superoxide Dismutase fromThermoascus aurantiacus

Shi-Jin

Guo

Liu

et al. 2007

Bioscience, Biotechnology, and Biochemistry

View full text Add to dashboard Cite

“…Therefore, a better understanding of the mechanism by which it protects itself against ROS would be of interest. A themostable superoxide dismutase was found in the genomic sequence of A. pernix and characterized (16). However, additional enzymes related to oxidative damage have not been reported.…”

mentioning

confidence: 99%

Characterization of Novel Hexadecameric Thioredoxin Peroxidase from Aeropyrum pernix K1

Jeon¹,

Ishikawa

2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

A gene (APE2278) encoding the peroxiredoxin (Prx) homologous protein of yeast and human was identified in the genome data base of the aerobic hyperthermophilic archaeon Aeropyrum pernix. We cloned the gene and produced the encoded protein in Escherichia coli cells. The isolated recombinant protein showed peroxidase activity in vitro and used the thioredoxin system of A. pernix as an electron donor. These results indicate that the recombinant protein is in fact thioredoxin peroxidase (ApTPx) of A. pernix. Immunoblot analysis revealed that the expression of ApTPx was induced as a cellular adaptation in response to the addition of exogenous H 2 O 2 and may exert an antioxidant activity in vivo. An analysis of the ApTPx oligomers by high pressure liquid chromatography and electron microscopic studies showed that ApTPx exhibited the hexadecameric protein forming 2-fold toroid-shaped structure with outer and inner diameters of 14 and 6 nm, respectively. These results indicated that ApTPx is a novel hexadecameric protein composed of two identical octamers. Although oligomerization of individual subunits does not take place through an intersubunit-disulfide linkage involving Cys 50 and Cys 213 , Cys 50 is essential for the formation of the hexadecamer. Mutagenesis studies suggest that the sulfhydryl group of Cys 50 is the site of oxidation by peroxide and that oxidized Cys 50 reacts with the sulfhydryl group of Cys 213 of another subunit to form an intermolecular disulfide bond. The resulting disulfide can then be reduced by thioredoxin. In support of this hypothesis, ApTPx mutants lacking either Cys 50 or Cys 213 showed no TPx activity, whereas the mutant lacking Cys 207 had a TPx activity. This is the first report on the biochemical and structural features of a novel hexadecameric thioredoxin peroxidase from the archaea.

show abstract

A Cambialistic SOD in a Strictly Aerobic Hyperthermophilic Archaeon, Aeropyrum pernix

Cited by 43 publications

References 0 publications

Biochemical Properties and Regulated Gene Expression of the Superoxide Dismutase from the Facultatively Aerobic Hyperthermophile Pyrobaculum calidifontis

Biochemical Properties and Regulated Gene Expression of the Superoxide Dismutase from the Facultatively Aerobic Hyperthermophile Pyrobaculum calidifontis

Purification, Characterization, and Molecular Cloning of a Thermostable Superoxide Dismutase fromThermoascus aurantiacus

Characterization of Novel Hexadecameric Thioredoxin Peroxidase from Aeropyrum pernix K1

Contact Info

Product

Resources

About