Bioenergetics of sulfur reduction in the hyperthermophilic archaeon Pyrococcus furiosus

Schicho, R. N.; Ma, Kesen; Adams, Michael W. W.; Kelly, Robert M.

doi:10.1128/jb.175.6.1823-1830.1993

Cited by 109 publications

(82 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, some of these organisms, such as P. furiosus, are able to grow in the absence of S0 by fermentation and produce H2. In these cases, So reduction was originally thought to be a mechanism of detoxifying inhibitory H2 (18 (42). Moreover, on the basis of the unusual ferredoxin-dependent "pyrosaccharolytic" pathway that P. furiosus is proposed to use for carbohydrate fermentation, it was calculated that So reduction is equivalent to an ATP yield of 0.5 mol of ATP per mol of S0 reduced (42).…”

Section: Resultsmentioning

confidence: 99%

“…In these cases, So reduction was originally thought to be a mechanism of detoxifying inhibitory H2 (18 (42). Moreover, on the basis of the unusual ferredoxin-dependent "pyrosaccharolytic" pathway that P. furiosus is proposed to use for carbohydrate fermentation, it was calculated that So reduction is equivalent to an ATP yield of 0.5 mol of ATP per mol of S0 reduced (42). It was therefore of some surprise to find that the sulfhydrogenase (sulfur:reduced ferredoxin oxidoreductase) activity of P. furiosus was located in the cytoplasm (26).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Sulfide dehydrogenase from the hyperthermophilic archaeon Pyrococcus furiosus: a new multifunctional enzyme involved in the reduction of elemental sulfur

1994

Self Cite

View full text Add to dashboard Cite

Pyrococcus furiosus is an anaerobic archaeon that grows optimally at 1000C by the fermentation of carbohydrates yielding acetate, C02, and H2 as the primary products. If elemental sulfur (SO) or polysulfide is added to the growth medium, H2S is also produced. The cytoplasmic hydrogenase of P. furiosus, which is responsible for H2 production with ferredoxin as the electron donor, has been shown to also catalyze the reduction of polysulfide to H2S (K. Ma, R. N. Schicho (33). The majority are strict anaerobes, and most are obligately dependent upon the reduction of elemental sulfur (S) to H2S for optimal growth. Molecular H2 or organic compounds serve as electron donors for the apparent respiration of So. Some of the heterotrophic species are able to grow in the absence of S by fermentation-type metabolisms that result in the production of H2. In such cases, the addition of So to the growth medium leads to H2S production and growth stimulation. Since the hyperthermophiles are the most slowly evolving of known life forms, it has been suggested that S0 respiration may represent one of the earliest mechanisms of energy conservation from an evolutionary perspective (40, 47).The mechanisms by which hyperthermophilic organisms reduce So to H2S and the natures of the enzymes involved are far from clear. The situation is complicated by the fact that the abiotic reduction of S0 can also occur at the growth temperatures of these organisms (9). Also, because of the low solubility of S in aqueous media, golysulfide is thought to be the true substrate for microbial S reduction (9,40,41 nism of H2S production from S0 has been investigated in only one autotrophic hyperthermophile, Pyrodictium brockii, an obligate S-reducing species which grows optimally at 1050C. This organism was shown to have a primitive membrane-bound electron transport chain for coupling H2 oxidation and S0 reduction (36). The chain contained hydrogenase, a cytochrome, and a novel quinone, but the So-reducing entity was not purified. In fact, there have been few reports on S5 reduction by mesophilic organisms. For example, Zophel and coworkers screened several different So-reducing bacteria for sulfur oxidoreductase activity (50) and the enzyme responsible in "Spirillum" strain 5175 (44) was postulated to be an iron-sulfur protein possibly associated with a c-type cytochrome (51). However, only one S0-reducing enzyme has been purified and characterized from a mesophile, that from Wolinella succinogenes (20,21,43), an organism which grows with formate as the electron donor and S0 as the electron acceptor (27). From sequencing analysis, it was postulated that its polysulfide reductase is composed of three subunits and is a molybdopterin-containing iron-sulfur protein (21).We are investigating the So-reducing activities of heterotrophic hyperthermophiles such as P. furiosus (18). This obligate anaerobe grows optimally at 100'C by the fermentation of carbohydrates and peptides in which excess reductant, generated mainly in the form of reduced ferredoxin (2,5,30)...

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Sulfide dehydrogenase from the hyperthermophilic archaeon Pyrococcus furiosus: a new multifunctional enzyme involved in the reduction of elemental sulfur

1994

Self Cite

View full text Add to dashboard Cite

show abstract

“…furiosus also reduces elemental sulfur (S 0 ) to H 2 S. This process decreases the amount of H 2 produced and has a stimulatory effect on growth, as indicated by an increase in cell density and growth rate (11). Moreover, during growth on maltose, the cell yield per gram of substrate used is 50% higher if S 0 is present in the medium (35). This suggests that the reduction of S 0 by P. furiosus is not merely a means of disposing of excess reductant but rather is an energy-conserving process.…”

mentioning

confidence: 99%

Purification and Characterization of a Membrane-Bound Hydrogenase from the Hyperthermophilic Archaeon Pyrococcus furiosus

2000

View full text Add to dashboard Cite

Highly washed membrane preparations from cells of the hyperthermophilic archaeon Pyrococcus furiosus contain high hydrogenase activity (9.4 mol of H 2 evolved/mg at 80°C) using reduced methyl viologen as the electron donor. The enzyme was solubilized with n-dodecyl-␤-D-maltoside and purified by multistep chromatography in the presence of Triton X-100. The purified preparation contained two major proteins (␣ and ␤) in an approximate 1:1 ratio with a minimum molecular mass near 65 kDa and contained ϳ1 Ni and 4 Fe atoms/mol. The reduced enzyme gave rise to an electron paramagnetic resonance signal typical of the so-called Ni-C center of mesophilic NiFe-hydrogenases. Neither highly washed membranes nor the purified enzyme used NAD(P)(H) or P. furiosus ferredoxin as an electron carrier, nor did either catalyze the reduction of elemental sulfur with H 2 as the electron donor. Using N-terminal amino acid sequence information, the genes proposed to encode the ␣ and ␤ subunits were located in the genome database within a putative 14-gene operon (termed mbh). The deduced sequences of the two subunits (Mbh 11 and 12) were distinctly different from those of the four subunits that comprise each of the two cytoplasmic NiFe-hydrogenases of P. furiosus and show that the ␣ subunit contains the NiFe-catalytic site. Six of the open reading frames (ORFs) in the operon, including those encoding the ␣ and ␤ subunits, show high sequence similarity (>30% identity) with proteins associated with the membrane-bound NiFe-hydrogenase complexes from Methanosarcina barkeri, Escherichia coli, and Rhodospirillum rubrum. The remaining eight ORFs encode small (<19-kDa) hypothetical proteins. These data suggest that P. furiosus, which was thought to be solely a fermentative organism, may contain a previously unrecognized respiratory system in which H 2 metabolism is coupled to energy conservation.Hydrogenases catalyze the reversible reduction of protons to hydrogen gas. They are found in a wide variety of microorganisms and enable them to use H 2 as a source of reductant under either aerobic or anaerobic conditions. Alternatively, fermentative-type organisms utilize hydrogenase to dispose of reductant without the need of terminal electron acceptors other than protons (1, 3). Hydrogenases can be divided into two major types, depending on the metals they contain (5). The so-called iron-only hydrogenases have high specific activities and usually function to evolve H 2 . Their catalytic site is comprised of a novel 6Fe cluster (26,29). The active site of nickel-and ironcontaining hydrogenases (NiFe-hydrogenases), on the other hand, consists of a binuclear NiFe center (12, 36). The NiFehydrogenases are less active than their Fe-only counterparts, and their physiological role is usually to oxidize H 2 . In aerobic H 2 -oxidizing bacteria, NiFe-hydrogenases can function both as cytoplasmic, NAD-reducing enzymes and as part of conventional membrane-bound (MB) respiratory chains where O 2 is the terminal electron acceptor (4, 9). In contrast, in anaerobic ...

show abstract

“…These have fermentative-type metabolisms and produce H 2 during growth, although they also produce H 2 S if S 0 is added to the growth medium. S 0 reduction was thought to be a mechanism of detoxifying inhibitory H 2 (23), but a more recent study showed that H 2 S production plays a role in energy conservation by an as yet unknown mechanism (62). The best studied of the hyperthermophiles that are not obligately S 0 dependent is Pyrococcus furiosus, which grows optimally at 100ЊC (23).…”

mentioning

confidence: 99%

Effects of elemental sulfur on the metabolism of the deep-sea hyperthermophilic archaeon Thermococcus strain ES-1: characterization of a sulfur-regulated, non-heme iron alcohol dehydrogenase

et al. 1995

Self Cite

View full text Add to dashboard Cite

The strictly anaerobic archaeon Thermococcus strain ES-1 was recently isolated from near a deep-sea hydrothermal vent. It grows at temperatures up to 91؇C by the fermentation of peptides and reduces elemental sulfur (S 0 ) to H 2 S. It is shown here that the growth rates and cell yields of strain ES-1 are dependent upon the concentration of S 0 in the medium, and no growth was observed in the absence of S 0 . The activities of various catabolic enzymes in cells grown under conditions of sufficient and limiting S 0 concentrations were investigated. These enzymes included alcohol dehydrogenase (ADH); formate benzyl viologen oxidoreductase; hydrogenase; glutamate dehydrogenase; alanine dehydrogenase; aldehyde ferredoxin (Fd) oxidoreductase; formaldehyde Fd oxidoreductase; and coenzyme A-dependent, Fd-linked oxidoreductases specific for pyruvate, indolepyruvate, 2-ketoglutarate, and 2-ketoisovalerate. Of these, changes were observed only with ADH, formate benzyl viologen oxidoreductase, and hydrogenase, the specific activities of which all dramatically increased in cells grown under S 0 limitation. This was accompanied by increased amounts of H 2 and alcohol (ethanol and butanol) from cultures grown with limiting S 0 . Such cells were used to purify ADH to electrophoretic homogeneity. ADH is a homotetramer with a subunit M r of 46,000 and contains 1 g-atom of Fe per subunit, which, as determined by electron paramagnetic resonance analyses, is present as a mixture of ferrous and ferric forms. No other metals or acid-labile sulfide was detected by colorimetric and elemental analyses. ADH utilized NADP(H) as a cofactor and preferentially catalyzed aldehyde reduction. It is proposed that, under S 0 limitation, ADH reduces to alcohols the aldehydes that are generated by fermentation, thereby serving to dispose of excess reductant.Hyperthermophiles are a recently discovered group of microorganisms that have the remarkable property of growing at temperatures of 90ЊC and above (1, 2, 64, 65). They have been isolated from a variety of geothermally heated environments, and almost all are classified as Archaea (formerly Archaeobacteria [75]). The majority are strict anaerobes, and most are obligately dependent upon the reduction of elemental sulfur (S 0 ) to H 2 S for optimal growth. Various organic compounds and molecular H 2 serve as electron donors for the apparent respiration of S 0 . The mechanism of S 0 reduction in one autotrophic hyperthermophile, Pyrodictium brockii, an obligate S 0 -reducing species which grows optimally at 105ЊC, has been investigated. This organism was shown to have a primitive membrane-bound electron transport chain for coupling H 2 oxidation and H 2 S production (52), although the S 0 -reducing entity was not purified.On the other hand, some of the heterotrophic hyperthermophiles are able to grow well in the absence of S 0 . These have fermentative-type metabolisms and produce H 2 during growth, although they also produce H 2 S if S 0 is added to the growth medium. S 0 reduction was thought to be...

show abstract

Bioenergetics of sulfur reduction in the hyperthermophilic archaeon Pyrococcus furiosus

Cited by 109 publications

References 55 publications

Sulfide dehydrogenase from the hyperthermophilic archaeon Pyrococcus furiosus: a new multifunctional enzyme involved in the reduction of elemental sulfur

Sulfide dehydrogenase from the hyperthermophilic archaeon Pyrococcus furiosus: a new multifunctional enzyme involved in the reduction of elemental sulfur

Purification and Characterization of a Membrane-Bound Hydrogenase from the Hyperthermophilic Archaeon Pyrococcus furiosus

Effects of elemental sulfur on the metabolism of the deep-sea hyperthermophilic archaeon Thermococcus strain ES-1: characterization of a sulfur-regulated, non-heme iron alcohol dehydrogenase

Contact Info

Product

Resources

About