A novel octameric AMP‐forming acetyl‐CoA synthetase from the hyperthermophilic crenarchaeon <i>Pyrobaculum aerophilum</i>

Bräsen, Christopher; Urbanke, Claus; Schönheit, Peter

doi:10.1016/j.febslet.2004.12.016

Cited by 34 publications

(31 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under conditions in which acetate is incorporated into the gluconeogenesis pathway, the AMP-forming acetyl-CoA synthetase and phosphoenolpyruvate synthase could produce substantial amounts of AMP. The T. pendens AMP-forming acetyl-CoA synthetase (Tpen_0893) has a very high level of similarity to the P. aerophilum enzyme that has been characterized (4). A large amount of AMP may also be generated by ribose-phosphate pyrophosphokinase, which is required for pyrimidine synthesis, and phosphoribosyltransferases.…”

Section: Resultsmentioning

confidence: 99%

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

Anderson

Rodriguez²,

Susanti

et al. 2008

J Bacteriol

View full text Add to dashboard Cite

We report the complete genome of Thermofilum pendens, a deeply branching, hyperthermophilic member of the order Thermoproteales in the archaeal kingdom Crenarchaeota. T. pendens is a sulfur-dependent, anaerobic heterotroph isolated from a solfatara in Iceland. It is an extracellular commensal, requiring an extract of Thermoproteus tenax for growth, and the genome sequence reveals that biosynthetic pathways for purines, most amino acids, and most cofactors are absent. In fact, T. pendens has fewer biosynthetic enzymes than obligate intracellular parasites, although it does not display other features that are common among obligate parasites and thus does not appear to be in the process of becoming a parasite. It appears that T. pendens has adapted to life in an environment rich in nutrients. T. pendens was known previously to utilize peptides as an energy source, but the genome revealed a substantial ability to grow on carbohydrates. T. pendens is the first crenarchaeote and only the second archaeon found to have a transporter of the phosphotransferase system. In addition to fermentation, T. pendens may obtain energy from sulfur reduction with hydrogen and formate as electron donors. It may also be capable of sulfur-independent growth on formate with formate hydrogen lyase. Additional novel features are the presence of a monomethylamine:corrinoid methyltransferase, the first time that this enzyme has been found outside the Methanosarcinales, and the presence of a presenilin-related protein.The predicted highly expressed proteins do not include proteins encoded by housekeeping genes and instead include ABC transporters for carbohydrates and peptides and clustered regularly interspaced short palindromic repeat-associated proteins.Crenarchaeota is one of the two major divisions of the Archaea, and it is the least well represented taxon in terms of genome sequences. Only seven crenarchaeal genomes have been sequenced and published so far, and three of these are genomes of members of the genus Sulfolobus. For the order Thermoproteales, the complete sequence of only one organism, Pyrobaculum aerophilum, has been determined and published so far, although several more species of Pyrobaculum, Caldivirga maquilingensis, and Thermoproteus tenax have been or are currently being sequenced (29). Thermofilum pendens represents a deep branch in the order Thermoproteales, and this organism grows only in rich medium with a fraction of the polar lipids of T. tenax (64), a property that has not been seen before in archaea. Therefore, it was an attractive sequencing target. We report here the genome sequence of T. pendens and analysis of the type strain, T. pendens Hrk5.T. pendens is an anaerobic, sulfur-dependent hyperthermophile isolated from a solfatara in Iceland. It forms long thin filaments and may have an unusual mode of reproduction in which spherical bulges form at one end of the cell. It requires complex media and a lipid extract from the related organism T. tenax for growth (64). The unknown lipid may be a cellular componen...

show abstract

Section: Resultsmentioning

confidence: 99%

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

Anderson

Rodriguez²,

Susanti

et al. 2008

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…Acyl-CoA synthetases are usually described as monomers or homodimers composed of 70-to 75-kDa subunits. A homotetrameric structure is therefore unusual and may be a consequence of the thermostability of the enzyme (5).…”

Section: Resultsmentioning

confidence: 99%

3-Hydroxypropionyl-Coenzyme A Synthetase from Metallosphaera sedula , an Enzyme Involved in Autotrophic CO ₂ Fixation

2008

View full text Add to dashboard Cite

A modified 3-hydroxypropionate cycle has been proposed as the autotrophic CO 2 fixation pathway for the thermoacidophilic crenarchaeon Metallosphaera sedula. The cycle requires the reductive conversion of 3-hydroxypropionate to propionyl-coenzyme A (propionyl-CoA). The specific activity of the 3-hydroxypropionate-, CoA-, and MgATP-dependent oxidation of NADPH in autotrophically grown cells was 0.023 mol min ؊1 mg protein ؊1 . The reaction sequence is catalyzed by at least two enzymes. The first enzyme, 3-hydroxypropionylCoA synthetase, catalyzes the following reaction: 3-hydroxypropionate ؉ ATP ؉ CoA 3 3-hydroxypropionylCoA ؉ AMP ؉ PP i . The enzyme was purified 95-fold to a specific activity of 18 mol min ؊1 mg protein ؊1 from autotrophically grown M. sedula cells. An internal peptide sequence was determined and a gene encoding a homologous protein identified in the genome of Sulfolobus tokodaii; similar genes were found in S. solfataricus and S. acidocaldarius. The gene was heterologously expressed in Escherichia coli, and the His-tagged protein was purified. Both the native enzyme from M. sedula and the recombinant enzyme from S. tokodaii not only activated 3-hydroxypropionate to its CoA ester but also activated propionate, acrylate, acetate, and butyrate; however, with the exception of propionate, the affinities for these substrates were reduced. 3-Hydroxypropionyl-CoA synthetase is up-regulated eightfold in autotrophically versus heterotrophically grown M. sedula, supporting its proposed role during CO 2 fixation in this archaeon and possibly other members of the Sulfolobaceae family.

show abstract

“…A continuous spectrophotometric assay monitoring CoA thioester formation from acids was applied for examination of the substrate specificities and kinetic properties of recombinant SCS Tk and ACS II Tk (21). The reaction mixture (1000 l) was composed of 10 mM carboxylic acid, 1 mM ATP, 1.5 mM CoA, 5 mM MgCl 2 , 1.5 mM phosphoenolpyruvate, and 1.5 mM NADH in 50 mM MES-NaOH buffer (pH 6.5) together with a mixture of pyruvate kinase/lactate dehydrogenase from rabbit muscle (Sigma) as coupling enzymes.…”

Section: Methodsmentioning

confidence: 99%

“…Archaeal ADP-forming ACSs have been characterized from the hyperthermophilic P. furiosus (11)(12)(13), Archaeoglobus fulgidus (19,20), Methanocaldococcus jannaschii (20), and Pyrobaculum aerophilum (21) and the halophilic Haloarcula marismortui (21,22). The enzymes display a common structure and are composed of two ␣-and two ␤-subunits (␣ 2 ␤ 2 ) or are homodimers of ␣-␤ fusion proteins.…”

mentioning

confidence: 99%

A Novel ADP-forming Succinyl-CoA Synthetase in Thermococcus kodakaraensis Structurally Related to the Archaeal Nucleoside Diphosphate-forming Acetyl-CoA Synthetases

Shikata

Fukui

Atomi

et al. 2007

Journal of Biological Chemistry

View full text Add to dashboard Cite

We have identified and characterized a structurally novel succinyl-CoA synthetase (SCS) from the hyperthermophilic Archaea Thermococcus kodakaraensis. The presence of an SCS completes the metabolic pathway from glutamate to succinate in Thermococcales, which had not been clarified because of the absence of classical SCS homologs on their genomes. The SCS from T. kodakaraensis (SCS Tk ) is a heteromeric enzyme (␣ 2 ␤ 2 ) encoded by TK1880 (␣-subunit) and TK0943 (␤-subunit). Although both SCS Tk and classical SCSs harbor the five domains present in enzymes of the acyl-CoA synthetase (nucleoside diphosphate-forming) superfamily, the domain order and distribution among subunits in SCS Tk (␣-subunit, domains 1-2-5; ␤-subunit, domains 3-4) are distinct from those of classical SCSs (␣-subunit, domains 1-2; ␤-subunit, domains 3-4-5) and instead resemble the acetyl-CoA synthetases from Pyrococcus furiosus (ACSs I Pf and II Pf ). Comparison of the four Thermococcales genomes revealed that each strain harbors five ␣-and two ␤-subunit homologs. Sequence similarity suggests that the ␤-subunit of SCS Tk is also a component of the presumed ACS II from T. kodakaraensis (ACS II Tk ). We coexpressed the ␣/␤-genes of SCS Tk (TK1880/TK0943) and of ACS II Tk (TK0139/ TK0943). ACS II Tk recognizes a broad range of hydrophobic/ aromatic acid compounds, as is the case with ACS II Pf , whereas SCS Tk displays a distinct and relatively strict substrate specificity for several acids, including succinate. This indicates that the ␣-subunits are responsible for the distinct substrate specificities of SCS Tk and ACS II Tk .Thermococcus and Pyrococcus species are hyperthermophilic Archaea that preferentially utilize peptides/amino acids for cell growth (1). It is presumed that amino acids are first deaminated to 2-oxo acids by aminotransferases, with 2-oxoglutarate as a key amino acceptor (2). The generated glutamate is converted back to 2-oxoglutarate by oxidative deamination catalyzed by glutamate dehydrogenase (3). The 2-oxo acids are then converted to CoA thioester compounds by oxidative decarboxylation. Ferredoxin-dependent oxidoreductases catalyze these reactions, and a number of enzymes with distinct substrate specificities have been identified in Pyrococcus furiosus (4 -7). Closely related genes are also found on the genomes of Thermococcus kodakaraensis (8), Pyrococcus abyssi (9), and Pyrococcus horikoshii (10). The final step is the hydrolysis of the thioester bond, releasing a carboxylic acid and CoA accompanied by substrate level phosphorylation, an important energy conservation reaction in these hyperthermophiles. The ADP-forming acetyl-CoA synthetases I and II from P. furiosus (ACSs I Pf 2 and II Pf ) have been identified to be involved in this step (11-14) and exhibit activity not only for acetyl-CoA but also for branched-chain acyl-CoAs (ACSs I Pf and II Pf ) and aryl-CoAs (ACS II Pf ) (13). The substrate specificities of the two enzymes are consistent with the preferential consumption of Leu, Ile, and Phe by P. furiosus during...

show abstract

A novel octameric AMP‐forming acetyl‐CoA synthetase from the hyperthermophilic crenarchaeon Pyrobaculum aerophilum

Cited by 34 publications

References 26 publications

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

3-Hydroxypropionyl-Coenzyme A Synthetase from Metallosphaera sedula , an Enzyme Involved in Autotrophic CO ₂ Fixation

A Novel ADP-forming Succinyl-CoA Synthetase in Thermococcus kodakaraensis Structurally Related to the Archaeal Nucleoside Diphosphate-forming Acetyl-CoA Synthetases

Contact Info

Product

Resources

About

A novel octameric AMP‐forming acetyl‐CoA synthetase from the hyperthermophilic crenarchaeon Pyrobaculum aerophilum

Cited by 34 publications

References 26 publications

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

Genome Sequence of Thermofilum pendens Reveals an Exceptional Loss of Biosynthetic Pathways without Genome Reduction

3-Hydroxypropionyl-Coenzyme A Synthetase from Metallosphaera sedula , an Enzyme Involved in Autotrophic CO 2 Fixation

A Novel ADP-forming Succinyl-CoA Synthetase in Thermococcus kodakaraensis Structurally Related to the Archaeal Nucleoside Diphosphate-forming Acetyl-CoA Synthetases

Contact Info

Product

Resources

About

3-Hydroxypropionyl-Coenzyme A Synthetase from Metallosphaera sedula , an Enzyme Involved in Autotrophic CO ₂ Fixation