| purification and properties of an archaebacterial enzyme: citrate synthase from sulfolobus solfataricus. | citrate synthase from the thermoacidophilic archaebacterium sulfolobus solfataricus was purified to homogeneity. the synthase is a dimer composed of subunits of mr approximately equal to 40,000. the km values of acetyl-coa and oxalacetate are 7 microm and 20 microm, respectively. nadh (ki = 3.5mm) and atp (ki = 0.36mm) are competitive inhibitors vs acetyl-coa. the dimeric structure and the inhibition by nucleotides (atp greater than nadh) correlate the archaebacterial enzyme to synthases from eu ... | 1988 | 3130075 |
| archaebacterial malate dehydrogenases. the enzymes from the thermoacidophilic organisms sulfolobus acidocaldarius and thermoplasma acidophilum show a-side stereospecificity for nad+. | the stereoselective transfer of hydrogen from nadh to oxaloacetate catalysed by malate dehydrogenases (ec 1.1.1.37) from the thermoacidophilic archaebacteria sulfolobus acidocaldarius and thermoplasma acidophilum was studied by the p.m.r. method described by zhou & wong [(1981) j. biochem. biophys. methods 4, 329-338]. both enzymes are a-side (pro-r) stereospecific for nadh. | 1985 | 2985051 |
| analysis and characterization of the folates in the nonmethanogenic archaebacteria. | a detailed analysis of the folate coenzymes in the nonmethanogenic archaebacteria has been performed. by using the lactobacillus casei microbiological assay for folates, the levels of folates in sulfolobus solfataricus and sulfolobus acidocaldarius were found to be 3.7 and 8.3 ng/g (dry weight) of cells, respectively, compared with 88,000 and 28,000 ng/g (dry weight) of cells in halobacterium halobium and halobacterium strain gn-1, respectively. the levels of folates found in the sulfolobus spp. ... | 1988 | 3139633 |
| a restriction endonuclease suai from the thermoacidophilic archaebacterium sulfolobus acidocaldarius. | a type ii restriction endonuclease (suai) has been isolated from the thermoacidophilic archaebacterium sulfolobus acidocaldarius. the enzyme is an isoschizomer of bspri. it does not cut s. acidocaldarius dna, as the recognition sequence ggcc in this dna contains modified nucleotide(s). the enzyme is most active at 60-70 degrees c and is highly thermostable. | 1985 | 2996942 |
| oxalacetate decarboxylase and pyruvate carboxylase activities, and effect of sulfhydryl reagents in malic enzyme from sulfolobus solfataricus. | malic enzyme (s)-malate: nadp+ oxidoreductase (oxaloacetate-decarboxylating, ec 1.1.1.40) purified from the thermoacidophilic archaebacterium sulfolobus solfataricus, strain mt-4, catalyzed the metal-dependent decarboxylation of oxaloacetate at optimum ph 7.6 at a rate comparable to the decarboxylation of l-malate. the oxaloacetate decarboxylase activity was stimulated about 50% by nadp but only in the presence of mgcl2, and was strongly inhibited by l-malate and nadph which abolished the nadp a ... | 1988 | 3142524 |
| studies on the citryl-coa-dependent inhibition of citrate-synthase with source variants from baker's yeast, escherichia coli and sulfolobus solfataricus. | 1) citrate synthase from pig heart has previously been shown to display complex kinetic characteristics in the reactions with citryl-coa, resulting in inhibition. the synthase from another eukaryotic source, baker's yeast, yields the same complex kinetics. 2) synthases from a gram-negative prokaryote, e. coli, and from an archaebacterium, s. solfataricus, catalyse the reactions of citryl-coa in kinetics of the michaelis-menten type. a comparison of the rates of citryl-coa hydrolysis (v') and phy ... | 1988 | 3144288 |
| s-adenosylmethionine synthetase in the thermophilic archaebacterium sulfolobus solfataricus. purification and characterization of two isoforms. | two isoforms of methionine adenosyltransferase (s-adenosylmethionine synthetase), a and b, have been partially purified from sulfolobus solfataricus, a thermophilic archaebacterium optimally growing at 87 degrees c. the chromatographic procedure, involving hydrophobic chromatography on a phenyl-sepharose column as a major step, results in 330-fold and 150-fold purification of adenosylmethionine synthetase a and b respectively. the apparent molecular masses, estimated by gel filtration, are 180 k ... | 1988 | 3142771 |
| s-adenosylmethionine decarboxylase from the thermophilic archaebacterium sulfolobus solfataricus. | | 1988 | 3151235 |
| a dna polymerase from a thermoacidophilic archaebacterium: evolutionary and technological interests. | the archaebacteria constitute a group of prokaryotes with an intermediate phylogenetic position between eukaryotes and eubacteria. the study of their dna polymerases may provide valuable information about putative evolutionary relationships between prokaryotic and eukaryotic dna polymerases. as a first step towards this goal, we have purified to near homogeneity a dna polymerase from the thermoacidophilic archaebacterium sulfolobus acidocaldarius. this enzyme is a monomeric protein of 100 kda wh ... | 1988 | 3145018 |
| structure-activity relationships of sparsomycin and its analogues. inhibition of peptide bond formation in cell-free systems and of l1210 and bacterial cell growth. | the biological activity of 14 analogues of sparsomycin (1) was studied in cell-free systems of escherichia coli, saccharomyces cerevisiae, and sulfolobus solfataricus by measuring the inhibition of protein synthesis. the inhibition of l1210 colony formation in soft agar and bacterial cell growth in solid as well as in liquid medium was also examined. each analogue possesses not more than two structural modifications of the sparsomycin molecule. this enabled us to determine unambiguously several ... | 1987 | 3543365 |
| glucose dehydrogenase from the thermoacidophilic archaebacterium sulfolobus solfataricus. | glucose dehydrogenase has been purified to homogeneity from cell extracts of the extreme thermoacidophilic archaebacterium sulfolobus solfataricus. the enzyme utilizes both nad+ and nadp+ as coenzyme and catalyses the oxidation of several monosaccharides to the corresponding glyconic acid. substrate specificity and oxidation rate depend on the coenzyme present; when nad+ is used, the enzyme binds and oxidizes specifically sugars presenting equatorial orientation of hydroxy groups at c-2, c-3 and ... | 1986 | 3827812 |
| two contrary modes of chemolithotrophy in the same archaebacterium. | sulphur-dependent archaebacteria, which are found around nearly boiling continental solfataric springs and mud holes, can be assigned to two distinct branches: the aerobic, sulphur-oxidizing sulfolobales and the strictly anaerobic sulphur-reducing thermoproteales. here, we report the isolation of a group of extremely thermophilic solfataric archaebacteria that are able to grow either strictly anaerobically by reduction, or fully aerobically by oxidation of molecular sulphur, depending on the oxy ... | 1985 | 3919307 |
| structure and polymorphism of bipolar isopranyl ether lipids from archaebacteria. | we describe in this work the structure and polymorphism of a variety of lipids extracted from sulfolobus solfataricus, an extreme thermoacidophilic archaebacterium growing at about 85 degrees c and ph 2. these lipids are quite different from the usual fatty acid lipids of eukaryotes and prokaryotes: each molecule consists of two c40 omega-omega' biphytanyl residues (with 0 to 4 cyclopentane groups per residue), ether linked at both ends to two (variably substituted) glycerol or nonitol groups. f ... | 1985 | 3923203 |
| a comparison of the translational diffusion of a normal and a membrane-spanning lipid in l alpha phase 1-palmitoyl-2-oleoylphosphatidylcholine bilayers. | we have used the fluorescence recovery after photobleaching technique to study the translational diffusion, in l alpha phase multibilayers of 1-palmitoyl-2-oleoylphosphatidylcholine (popc), of fluorescent derivatives of 1-palmitoyl-2-oleoylphosphatidylethanolamine (nbd-pope) and a membrane-spanning phosphatidylethanolamine (nbd-mspe). the latter derivative was prepared from a membrane-spanning glycerol-dialkyl-glycerol tetraether lipid isolated from the thermophilic and acidophilic archaebacteri ... | 1985 | 3924584 |
| rna polymerase subunit homology among cyanobacteria, other eubacteria and archaebacteria. | rna polymerase purified from vegetative cells of the cyanobacterium anabaena sp. strain pcc 7120 contains a dissociable sigma factor and a core of five subunits: the beta', beta, and two alpha subunits characteristic of all eubacteria and an additional 66,000-molecular-weight polypeptide called gamma. fifteen of fifteen strains of unicellular and filamentous cyanobacteria tested contained a serologically related gamma protein. antiserum to gamma reacted with escherichia coli beta' and the a subu ... | 1988 | 3137214 |
| [subordination of the taxa of gram-negative bacteria determined by numerical analysis methods]. | various numerical methods were used to estimate the coordination of taxa of gram-negative aerobic and facultative anaerobic organoheterotrophic and chemolithotrophic bacteria. stable phena were found to be formed by cultures belonging to the families rhizobiaceae, halobacteriaceae, enterobacteriaceae, nitrobacteriaceae (except the genus nitrobacter), and methylomonadaceae (except the genus methylococcus). the unstable position was found in the genera thermus, zoogloea, xanthomonas, sulfolobus, m ... | 1986 | 3523170 |
| atp-dependent dna topoisomerase from the archaebacterium sulfolobus acidocaldarius. relaxation of supercoiled dna at high temperature. | a topoisomerase, able to relax negatively supercoiled dna, has been isolated from the archaebacterium sulfolobus acidocaldarius. relaxation was fully efficient in vitro between 70 degrees c and 80 degrees c and was dependent on the presence of atp and magnesium ions. the enzyme did not exhibit gyrase-like activity and was poorly sensitive to gyrase inhibitors. these properties are reminiscent of eukaryotic type ii topoisomerases. however, the enzyme was unable to relax positively supercoiled dna ... | 1984 | 6096554 |
| immunological comparison of ribosomal proteins from archaebacteria. | antisera were raised in rabbits against ribosomal proteins of methanobacterium bryantii and used to analyze immunological relationships to ribosomes from other archaebacteria, from eubacteria, and from yeasts. cross-reaction could be detected within the methanogens and with a member of the extreme halophiles; the degree of immunological similarity reflected the relationship delineated by 16s ribosomal ribonucleic acid oligonucleotide analysis (fox et al., science 209:457-463, 1980). with the met ... | 1981 | 6167563 |
| taxonomic relations between archaebacteria including 6 novel genera examined by cross hybridization of dnas and 16s rrnas. | dnas from 16 species of archaebacteria including 6 novel isolates were hybridized with 16s rrnas from 7 species representing different orders or groups of the urkingdom of archaebacteria. the yields, normalized for the number of genes per microgram of dna, and the temperature stabilities of all hybrids were determined and related to each other. a taxonomic tree constructed from such fractional stability data reveals the same major divisions as that derived from comparative cataloging of 16s rrna ... | 1982 | 6178834 |
| genome organization and transcription in archaebacteria. | the genome organization of the archaebacteria is investigated in three model systems: a) rrna genes of various archaebacteria, b) a plasmid of 15.6 kb from sulfolobus acidocaldarius which exists in free or integrated form, c) the 59 kb genome of phage phi h of halobacterium halobium as a model for the unusual structural variability of dna in this organism. several variants of this phage have been isolated, their genomes differ by several insertions, a deletion, and an inversion. the frequent inv ... | 1984 | 6202564 |
| an unusual 5s rrna, from sulfolobus acidocaldarius, and its implications for a general 5s rrna structure. | the nucleotide sequence of the 5s ribosomal rna of the thermoacidophilic archaebacterium sulfolobus acidocaldarius was determined. the high degree of evident secondary structure in the molecule has implications for the common higher order structure of other 5s rrnas, both bacterial and eukaryotic. | 1981 | 6273825 |
| putative introns in trna genes of prokaryotes. | sequences of two putative trna genes, for serine and leucine, from the archaebacterium sulfolobus solfataricus contain intervening sequences in the anticodon region. furthermore, the genes lack encoded cca 3' termini and are flanked by a + t-rich dna segments. the introns can both form the same secondary structure, which is a double-helical extension of the anticodon stalk. the resulting structure contains two symmetrically placed 3-base bulge loops, in which are located cleavage sites for the i ... | 1983 | 6304706 |
| reverse gyrase--a topoisomerase which introduces positive superhelical turns into dna. | an enzymatic activity which converts closed circular dna into a positively supercoiled form is present in cellular extracts of sulfolobus, an acidothermophilic archaebacterium. this novel enzyme is a type ii dna topoisomerase and is active only at temperatures greater than 55 degrees c, in the presence of atp and mg2+. | 1984 | 6328327 |
| histone-like protein in the archaebacterium sulfolobus acidocaldarius. | the archaebacterium thermoplasma acidophilum contains a basic chromosomal protein remarkably similar to the histones of eukaryotes. therefore, it was of interest to examine a different archaebacterium for similar proteins. we chose to examine sulfolobus acidocaldarius because it is thermophilic, like t. acidophilum, but nevertheless the two organisms are not particularly closely related. two major chromosomal proteins were found in s. acidocaldarius. the smaller of these was soluble in 0.2 m h2s ... | 1983 | 6418207 |
| sensitivity of thermoacidophilic archaebacteria to alpha-sarcin. | the protein synthesis machinery of sulfolobus solfataricus , a thermoacidophilic archaebacterium, is insensitive to most of the known antibiotics that interfere with elongation. alpha-sarcin, a cytotoxic protein, inhibits protein synthesis on eukaryotic systems by cleaving a specific sequence of the large rrna. alpha-sarcin is capable of inhibiting protein synthesis on s. solfataricus producing a fragment under conditions similar to those which produce it in yeast ribosomes. this result suggests ... | 1984 | 6427011 |
| the amino acid sequence of a small dna binding protein from the archaebacterium sulfolobus solfataricus. | the thermoacidophilic archaebacterium sulfolobus solfataricus possesses several dna binding proteins which may have a histone-like function. two particularly dominant species have molecular masses of 7 and 10 kda, respectively. we have purified one of the small proteins which occurs in relatively large amount and have determined its amino acid sequence. the protein is characterized by a high lysine content; in the n-terminal region the lysine residues occur in an alternating order: x-k-x-k-x-k-x ... | 1984 | 6436055 |
| protein phosphorylation in the archaebacterium sulfolobus acidocaldarius. | a number of proteins of the sulphur-dependent archaebacterium sulfolobus acidocaldarius are phosphorylated in vivo. the extent of phosphorylation depends on the state of growth and is most intense in the late exponential phase. some of the phosphorylated proteins are strongly associated with the bacterial membrane. ribosomal proteins and dna-dependent rna polymerase are not phosphorylated. studies in vitro show a high target selectivity. the activity is not increased by cyclic nucleotides. the r ... | 1984 | 6439562 |
| glucose metabolism in the extreme thermoacidophilic archaebacterium sulfolobus solfataricus. | sulfolobus solfataricus is a thermophilic archaebacterium able to grow at 87 degrees c and ph 3.5 on glucose as sole carbon source. the organism metabolizes glucose by two main routes. the first route involves an atp-dependent phosphorylation to give glucose 6-phosphate, which readily isomerizes to fructose 6-phosphate. in the second route, glucose is converted into gluconate by an nad+-dependent dehydrogenation; gluconate is then dehydrated to 2-keto-3-deoxygluconate, which, in turn, is cleaved ... | 1984 | 6440533 |
| archaebacterial elongation factor is adp-ribosylated by diphtheria toxin. | archaebacteria have been defined as a 'third primary kingdom' of cells in addition to the urkaryotes and the eubacteria. while the latter two correspond approximately to the conventional categories eukaryotes and prokaryotes respectively, the archaebacteria have up to now comprised four groups of microorganisms: the methanogenic bacteria, the extremely halophilic bacteria and the two thermoacidophilic genera sulfolobus and thermoplasma. based on ribosomal rna sequence homologies and lipid compos ... | 1980 | 6776409 |
| dna-dependent rna polymerase of thermoacidophilic archaebacteria. | the component compositions of the dna-dependent rna polymerases of the extremely thermophilic, anaerobic sulfur-respiring archaebacteria thermoproteus tenax and desulfurococcus mucosus strongly resemble each other but also that of the rna polymerase of sulfolobus acidocaldarius suggesting that both organisms belong to the same novel order thermoproteales, which together with the order represented by sulfolobus, forms the thermoacidophilic branch of archaebacteria. the component pattern of the rn ... | 1982 | 6800790 |
| insensitivity of archaebacterial ribosomes to protein synthesis inhibitors. evolutionary implications. | the effect on sulfolobus solfataricus (an extremely thermoacidophilic archaebacterium) of selected inhibitors affecting reactions of the polypeptide elongation cycle has been tested by using poly(u) and poly(ug) directed cell-free systems. the results reveal a unique pattern of antibiotic sensitivity of sulfolobus ribosomes with an inhibitory effect observed for only three of 60 compounds tested. through comparison with suitable eubacterial and eukaryotic cell-free systems the insensitivity of s ... | 1985 | 3924597 |
| amino acid sequence of a ferredoxin from thermoacidophilic archaebacterium, sulfolobus acidocaldarius. presence of an n6-monomethyllysine and phyletic consideration of archaebacteria. | the amino acid sequence of a ferredoxin from a thermoacidophilic archaebacterium, sulfolobus acidocaldarius, was determined by a combination of various conventional methods to be as follows: gly-ile-asp-pro-tyr-arg-thr-his-lys-pro-val-val-gly-asp-ser-ser-gly-his- lys-ile -tyr-gly-pro-val-glu-ser-pro-lys(me)-val-leu-gly-val-his-gly-thr-ile-val -gly-va l-asp-phe-asp-leu-cys-ile-ala-asp-gly-ser-cys-ile-thr-ala-cys-pro-val-as n-val-p he-gln-trp-tyr-glu-thr-pro-gly-his-pro-ala-ser-glu-lys-lys-ala-asp ... | 1985 | 3926756 |
| membrane-bound atpase of a thermoacidophilic archaebacterium, sulfolobus acidocaldarius. | the membranes of sulfolobus, a thermoacidophilic archaebacterium showed two types of atp hydrolyzing activity. one was that of a neutral atpase at an optimum ph around 6.5. this enzyme was activated by 10 mm sulfate with a shift of optimum ph to 5. in these respects, the enzyme was similar to membrane-bound atpase of thermoplasma, another thermoacidophilic archaebacterium, reported by searcy and whatley [1982) zbl. bakt. hyg., i. abt. orig. c3, 245-257). the enzyme hydrolyzed atp and other ntps, ... | 1985 | 3159431 |
| purification and characterization of dna polymerase from the archaebacterium sulfolobus acidocaldarius. | dna polymerase has been purified about 25,000-fold from the thermoacidophilic archaebacterium sulfolobus acidocaldarius. on sds-page the enzyme was observed to have a molecular weight of 100 kda and to be about 90% pure. the native molecular weight was 108 kda indicating that the enzyme is composed of a single polypeptide. activity gel analysis showed an active polypeptide of about 100 kda. under conditions promoting proteolysis this polypeptide was degraded to a slightly smaller form of 98 kda. ... | 1985 | 3927262 |
| sequence of the 16s rrna gene from the thermoacidophilic archaebacterium sulfolobus solfataricus and its evolutionary implications. | the sequence of the small-subunit rrna from the thermoacidophilic archaebacterium sulfolobus solfataricus has been determined and compared with its counterparts from halophilic and methanogenic archaebacteria, eukaryotes, and eubacteria. the s. solfataricus sequence is specifically related to those of the other archaebacteria, to the exclusion of the eukaryotic and eubacterial sequences, when examined either by evolutionary distance matrix analyses or by the criterion of minimum change (maximum ... | 1985 | 3936935 |
| subunit cell wall of sulfolobus acidocaldarius. | the cell wall of sulfolobus acidocaldarius has been isolated. cells were mechanically disrupted with a french press, and the cytoplasmic membrane was removed by extracting cell-envelope fragments with triton x-100. the triton-insoluble cell wall material retained the characteristic subunit structure when examined in the electron microscope. isolated cell wall fragments formed in open sheets that were easily separated from cytoplasmic contamination. chemical studies showed that the triton-insolub ... | 1974 | 4206874 |
| long-chain glycerol diether and polyol dialkyl glycerol triether lipids of sulfolobus acidocaldarius. | cells of sulfolobus acidocaldarius contain about 2.5% total lipid on a dry-weight basis. total lipid was found to contain 10.5% neutral lipid, 67.6% glycolipid, and 21.7% polar lipid. the lipids contained c(40)h(80) isopranol glycerol diethers. almost no fatty acids were present. the glycolipids were composed of about equal amounts of the glycerol diether analogue of glucosyl galactosyl diglyceride and a glucosyl polyol glycerol diether. the latter compound contained an unidentified polyol attac ... | 1974 | 4407015 |
| growth rates of sulfolobus acidocaldarius in nature. | turnover times for water passing through several sulfolobus acidocaldarius-containing springs were determined by measuring the dilution rates of small amounts of sodium chloride that were added to the springs. chloride was diluted out exponentially, while concentrations of the bacteria remained constant. additionally, temperature, ph, and chemical composition of the springs also remained constant during the time that the chloride was being diluted. the springs are thus steady-state systems, and ... | 1974 | 4597995 |
| oxidation of elemental sulfur by sulfolobus acidocaldarius. | oxidation of elemental sulfur by sulfolobus acidocaldarius, an autotroph which grows at high temperatures and low ph, was examined by use of (35)s-labeled elemental sulfur. when cultured at ph 3.2 and 70 c, s. acidocaldarius oxidized elemental sulfur essentially quantitatively to sulfuric acid. oxidation rate paralleled growth rate and decrease in ph of the culture medium. elemental sulfur was not oxidized under these conditions if the culture was poisoned with formaldehyde. during the growth ph ... | 1973 | 4706192 |
| population ecology of sulfolobus acidocaldarius. i. temperature strains. | | 1974 | 4847495 |
| sequences of the 5s rrnas of the thermo-acidophilic archaebacterium sulfolobus solfataricus (caldariella acidophila) and the thermophilic eubacteria bacillus acidocaldarius and thermus aquaticus. | we have determined the nucleotide sequences of the 5 s rrnas of three thermophilic bacteria: the archaebacterium sulfolobus solfataricus, also named caldariella acidophila, and the eubacteria bacillus acidocaldarius and thermus aquaticus. a 5 s rna sequence for the latter species had already been published, but it looked suspect on the basis of its alignment with other 5 s rna sequences and its base-pairing pattern. the corrected sequence aligns much better and fits in the universal five helix s ... | 1983 | 6878035 |
| archaebacterial trna contains 1-methylinosine at residue 57 in t psi c-loop. | 1-methylinosine was isolated from unfractionated trnas of sulfolobus acidocaldarius and halobacterium volcani. the structure of 1-methylinosine was characterized by ultraviolet absorption and mass spectral analysis. 1-methylinosine found in these archaebacterial trnas was located at residue 57 in t psi c-loop, indicating that the presence of 1-methylinosine is characteristic of archaebacteria. | 1982 | 7183961 |
| the 60 kda heat shock proteins in the hyperthermophilic archaeon sulfolobus shibatae. | one of the most abundant proteins in the hyperthermophilic archaeon sulfolobus shibatae is the 59 kda heat shock protein (tf55) that is believed to form a homo-oligomeric double ring complex structurally similar to the bacterial chaperonins. we discovered a second protein subunit in the s. shibatae ring complex (referred to as alpha) that is stoichiometric with tf55 (renamed beta). the gene and flanking regions of alpha were cloned and sequenced and its inferred amino acid sequence has 54.4% ide ... | 1995 | 7473746 |
| a 37.5 kb region of yeast chromosome x includes the sme1, mef2, gsh1 and csd3 genes, a tcp-1-related gene, an open reading frame similar to the dal80 gene, and a trna(arg). | the complete dna sequence of cosmid clone p59 comprising 37,549 bp derived from chromosome x was determined from an ordered set of subclones. the sequence contains 14 open reading frames (orfs) containing at least 100 consecutive sense codons. four of the orfs represent already known and sequenced yeast genes: b645 is identical to the sme1 gene encoding a protein kinase, required for induction of meiosis in yeast, d819 represents the mef2 gene probably encoding a second mitochondrial elongation ... | 1995 | 7483851 |
| the identification and partial characterisation of a novel inducible extracellular thermostable esterase from the archaeon sulfolobus shibatae. | extracellular esterases have so far only been reported in eubacteria, here we report the first identification and partial characterisation of a novel inducible extracellular esterase from the thermoacidophilic archaeon sulfolobus shibatae. this esterase exhibits remarkable stability to both acid and heat. esterase activity is induced by growth on a range of polyoxyethylenesorbitan (tween) compounds as sole carbon source. activity occurs over a wide temperature (25-99 degrees c) and ph (ph4.0-9.0 ... | 1995 | 7488139 |
| stability against temperature and external agents of vesicles composed of archael bolaform lipids and egg pc. | the bolaform lipid ple extracted from the thermophilic archaeon sulfolobus solfataricus and its mixtures with egg phosphatidyl-choline (egg pc) have been used to prepare sonicated vesicles. the leakage of entrapped calcein was continuously monitored by fluorescence dequenching. the half times of leakage have been used to compare vesicle stability under different conditions of temperature, lipid composition and presence of destabilizing agents like ca2+ ions and poly(ethylene glycol) (peg). it ha ... | 1995 | 7495852 |
| a secy homologous gene in the crenarchaeon sulfolobus acidocaldarius. | the nucleotide sequence of an open reading frame, located upstream of the gene for adenylate kinase, was determined in the thermoacidophile crenarchaeon sulfolobus acidocaldarius. data bank searches identified the sequence as a secy homologous gene. the dna derived protein sequence of total 463 amino acids contains 10 hydrophobic domains. a sequence alignment with other prokaryotic and eukaryotic secy sequences reveals significant homology, but the secy primary sequence of s. acidocaldarius show ... | 1995 | 7495856 |
| prevention of in vitro protein thermal aggregation by the sulfolobus solfataricus chaperonin. evidence for nonequivalent binding surfaces on the chaperonin molecule. | we have studied the effects of the sulfolobus solfataricus chaperonin on the aggregation and inactivation upon heating of four model enzymes: chicken egg white lysozyme (one 14.4-kda chain), yeast alpha-glucosidase (one 68.5-kda chain), chicken liver malic enzyme (four 65-kda subunits), and yeast alcohol dehydrogenase (four 37.5-kda subunits). when the proteins were heated in the presence of an equimolar amount of chaperonin, 1) the aggregation was prevented in all solutions; 2) the inactivation ... | 1995 | 7499301 |
| conformational cycle of the archaeosome, a tcp1-like chaperonin from sulfolobus shibatae. | the major heat shock proteins in the archaeon sulfolobus shibatae are similar to the cytosolic eukaryotic chaperonin and form an 18-subunit bitoroidal complex. two sequence-related subunits constitute a functional complex, named the archaeosome. the archaeosome exists in two distinct conformational states that are part of chaperonin functional cycle. the closed archaeosome complex binds atp and forms an open complex. upon atp hydrolysis, the open complex dissociates into subunits. free subunits ... | 1995 | 7499406 |
| confusion in the assignments of sulfolobus sequences to sulfolobus species. | | 1993 | 7504815 |
| bovine mitochondrial trnaphe, trnaser (agy) and trnaser (ucn): preparation using a new detection method and their properties in aminoacylation. | bovine mitochondrial trnaphe, trnaser (agy), and trnaser (ucn) possessing unusual structures were purified using a new hybridization assay system and their properties in aminoacylation were examined. bovine mitochondrial phenyl-alanyl- and seryl-trna synthetases could aminoacylate the same amino acid-specific trnas obtained not only from the mitochondria but also from other sources such as e. coli, thermus thermophilus, bovine and yeast cytosols and archaebacteria, sulfolobus acidocaldarius. on ... | 1988 | 3226927 |
| gene expression of a thermostable beta-galactosidase in mammalian cells and its application in assays of eukaryotic promoter activity. | the gene (lacs) encoding a thermostable beta-galactosidase enzyme (ss beta-gal) from the archaebacterium sulfolobus solfataricus has been cloned and expressed in simian cv1 and murine nih3t3 cell lines. the recombinant protein is an active enzyme that shows the same properties of thermophilicity and thermostability as the wild-type ss beta-gal and has no cytotoxic effect on the host cells. its possible use as a reporter gene is also proposed, and a comparison with other reporter gene systems is ... | 1994 | 7514880 |
| conformation of the central, three-helix junction of the 5 s ribosomal rna of sulfolobus acidocaldarius. | the current investigation has focused on the structure of the central, three-helix junction of the 5 s ribosomal rna from sulfolobus acidocaldarius, a thermoacidophilic archaebacterium. the 5 s molecule from s. acidocaldarius represents a paradigm for the study of the 5 s junction (and branched rna structures in general) due to its unusually high degree of predicted secondary structure and stability. in order to study the junction in isolation, a set of three rna heteroduplex molecules was assem ... | 1994 | 7520504 |
| separate pathways for excision and processing of 16s and 23s rrna from the primary rrna operon transcript from the hyperthermophilic archaebacterium sulfolobus acidocaldarius: similarities to eukaryotic rrna processing. | in the hyperthermophilic archaebacterium sulfolobus acidocaldarius, the mature 16s and 23s rrna are generated by processing of a 5000-nucleotide transcript. analysis of intermediates that accumulate in vivo indicates that the transcript contains 11 separate processing sites. the processing and maturation of 23s rrna appears to follow the typical archaebacterial pathway, utilizing a bulge-helix-bulge motif within the 23s processing helix as the substrate for an excision endonuclease. the precurso ... | 1994 | 7527119 |
| thermopsin. | | 1995 | 7674919 |
| organization of a sulfolobus solfataricus gene cluster homologous to the escherichia coli str operon. | the sulfolobus solfataricus s12, s7 and s10 ribosomal proteins and the elongation factor 1 alpha genes are organized in a sequence analogous to that in the escherichia coli str operon. northern analysis showed that the s12 gene belongs to a transcript different from that corresponding to the other three genes. compared to the sulfolobus acidocaldarius s12 and to the methanococcus vannielii s7 proteins, the s. solfataricus s12 and s7 proteins were 33 and 47 amino acids longer respectively. these ... | 1994 | 7527264 |
| ribosomal rna precursor processing by a eukaryotic u3 small nucleolar rna-like molecule in an archaeon. | an rna-containing endonuclease that catalyzes the excision and maturation of the 16s ribosomal rna (rrna) from the rrna primary transcript (pre-rrna) in the hyperthermophilic archaeon sulfolobus acidocaldarius has been characterized. the ribonucleoprotein was inactivated by micrococcal nuclease treatment and inactivation was reversed by reconstitution with bulk rna. a 159-nucleotide rna with sequence and structural similarity to u3 small nucleolar rnas of eukaryotes copurified with the endonucle ... | 1995 | 7538698 |
| a gene encoding a putative membrane protein homologous to the major facilitator superfamily of transporters maps upstream of the beta-glycosidase gene in the archaeon sulfolobus solfataricus. | we have identified a gene encoding a putative membrane protein homologous to the major facilitator superfamily, mapping upstream of the lacs gene in sulfolobus solfataricus. permeases from this family mediate secondary transport and are widely distributed among eubacteria and eukaryotes; the finding of an archaeal member suggests that this mechanism of transport evolved before the divergence of the three living domains. we also report a transcriptional mapping of the gene cluster. | 1995 | 7533760 |
| cloning, sequencing and transcript analysis of the gene encoding formylmethanofuran: tetrahydromethanopterin formyltransferase from the hyperthermophilic methanothermus fervidus. | the formylmethanofuran:tetrahydromethanopterin formyltransferase (ftr) from methanothermus fervidus was partially purified and its n-terminal amino acid sequence determined. using as probe a mixture of oligonucleotides derived from the ftr n-terminus, the corresponding gene (ftr) was cloned and sequenced. the ftr gene codes for 297 amino acids, corresponding to a molecular mass of 31,836 daltons, in contrast to the 41,000 daltons estimated for the protein by sodium dodecylsulphate-polyacrylamide ... | 1994 | 7506350 |
| tetraether lipid components from a thermoacidophilic archaebacterium. chemical structure and physical polymorphism. | as a continuation of an x-ray scattering study of the tetraether lipids extracted from the thermophilic archaebacterium sulfolobus solfataricus, the phase behaviour of four fractions of the complex polar lipid extract (ple) is described. each molecule of two of these fractions (p1 and gl) carries an unsubstituted glycerol headgroup, those of another (p2) no such group; the fourth fraction (wple) is obtained by water-washing ple, thus reducing its p2 content from approximately 48% to approximatel ... | 1988 | 3138418 |
| molecular cloning, nucleotide sequence, and expression of a carboxypeptidase-encoding gene from the archaebacterium sulfolobus solfataricus. | mammalian metallocarboxypeptidases play key roles in major biological processes, such as digestive-protein degradation and specific proteolytic processing. a sulfolobus solfataricus gene (cpsa) encoding a recently described zinc carboxypeptidase with an unusually broad substrate specificity was cloned, sequenced, and expressed in escherichia coli. despite the lack of overall sequence homology with known carboxypeptidases, seven homology blocks, including the zn-coordinating and catalytic residue ... | 1995 | 7559343 |
| thermoacidophilic archaebacteria contain bacterial-type ferredoxins acting as electron acceptors of 2-oxoacid:ferredoxin oxidoreductases. | thermoplasma acidophilum and sulfolobus acidocaldarius contain coenzyme a-acylating 2-oxoacid:ferredoxin oxidoreductases similar to those found in halophilic archaebacteria. a common feature of these enzymes is the formation of a free radical intermediate in the course of the catalytic cycle. the electron-accepting ferredoxins and a similar protein from desulfurococcus mobilis have been purified and characterized. in contrast to the [2fe-2s] ferredoxin of halobacterium halobium, the ferredoxins ... | 1982 | 6816594 |
| 1h-nmr and photo-cidnp spectroscopies show a possible role for trp23 and phe31 in nucleic acid binding by p2 ribonuclease from the archaeon sulfolobus solfataricus. | investigations were performed on recombinant ribonuclease p2 from sulfolobus solfataricus, previously cloned and expressed in escherichia coli [fusi, p., grisa, m., mombelli, e., consonni, r., tortora, p. and vanoni, m. (1995) gene 154, 99-103]. nmr and photo-cidnp spectroscopies showed that the enzyme possesses an aromatic cluster consisting of phe5, tyr7, phe31 and tyr33 while trp23 is fully exposed to solvent. phe31, tyr33 and trp23 are located within a triple stranded antiparallel beta-sheet ... | 1995 | 7556654 |
| three-dimensional arrangement of the cell wall protein of sulfolobus acidocaldarius. | the three-dimensional structure of the s-layer that surrounds the bacterium sulfolobus acidocaldarius is described in detail. pieces of the s-layer, which are two-dimensional crystals with p6 symmetry, have been studied by crystallographic analysis of electron micrographs of tilted specimens. in the density map, each asymmetric unit appears to consist of several domains connected by strong hinges. on the basis of the ragged appearance of the structure at torn edges, we now suggest that the singl ... | 1983 | 6876166 |
| isolation and cloning of a protein-serine/threonine phosphatase from an archaeon. | a divalent metal ion-stimulated protein-serine/threonine phosphatase, pp1-arch, was purified approximately 1,000-fold from the extreme acidothermophilic archaeon sulfolobus solfataricus (atcc 35091). purified preparations contained 40 to 70% of total protein as pp1-arch, as determined by assay-ing sodium dodecyl sulfate-polyacrylamide gels for protein phosphatase activity. the first 25 amino acids of the protein's sequence were identified, as well as an internal sequence spanning some 20 amino a ... | 1995 | 7592428 |
| transcription in archaea: similarity to that in eucarya. | we present homologies between archaeal and eucaryal dna-dependent rna polymerase (rnap) subunits and transcription factors. the sequences of the sulfolobus acidocaldarius subunits d, e, and n and alignments with eucaryal homologs are presented here. the similarities between archaeal transcription factors and their eucaryal homologs tfiib and tbp have been established in other laboratories. the archaeal rnap subunits h, k, and n, respectively, show high sequence similarity to abc27, abc23, and ab ... | 1995 | 7597027 |
| molecular cloning of the transcription factor tfiib homolog from sulfolobus shibatae. | the archaea (archaebacteria) constitute a group of prokaryotes that are phylogenetically distinct from eucarya (eukaryotes) and bacteria (eubacteria). although archaea possess only one rna polymerase, evidence suggests that their transcriptional apparatus is similar to that of eucarya. for example, archaea contain a homolog of the tata-binding protein which interacts with the tata-box like a-box sequence upstream of many archaeal genes. here, we report the cloning of a sulfolobus shibatae gene t ... | 1995 | 7597084 |
| new archaebacterial genes coding for redox proteins: implications for the evolution of aerobic metabolism. | archaebacterial respiratory chains are poorly understood at the molecular level. we have cloned and sequenced a cluster of five new genes from the archaebacterium sulfolobus acidocaldarius, four of them coding for redox proteins: a rieske iron-sulphur protein, a cytochrome b, a subunit ii of cytochrome oxidase and a blue copper protein (sulfocyanin). the fifth gene codes for a hydrophobic protein with no homologue in the databases. the gene organization and biochemical data suggest that all four ... | 1995 | 7608970 |
| the structure of the core polyol of the ether lipids from sulfolobus acidocaldarius. | the major ether-type lipid structures of sulfolobus acidocaldarius (atcc33909) were composed of caldarchaeol and calditoglycerocaldarchaeol. however, the characterization by nuclear magnetic resonance spectroscopy and mass spectrometry showed that the structure of calditol in calditoglycerocaldarchaeol is not nonitol, 2-(1',2',3'-trihydroxypropyl)1,2,3,4,5,6-hexahydroxyhexane, but 2-hydroxymethyl-1-(2,3-dihydroxypropoxy)2,3,4,5-cyclopentanetet raol with an ether linkage in the molecule. such an ... | 1995 | 7609602 |
| thermostability of respiratory terminal oxidases in the lipid environment. | the effect of the lipid environment on the thermostability of three respiratory terminal oxidases was determined. cytochrome-c oxidase from beef heart and bacillus stearothermophilus were used as representative proteins from mesophilic and thermophilic origin, respectively. quinol oxidase from the archaeon sulfolobus acidocaldarius represented the model for a extreme thermoacidophilic enzyme. all three integral membrane proteins were tested for their thermal inactivation in detergent and after r ... | 1995 | 7612641 |
| ferredoxin-dependent redox system of a thermoacidophilic archaeon, sulfolobus sp. strain 7. purification and characterization of a novel reduced ferredoxin-reoxidizing iron-sulfur flavoprotein. | to elucidate the ferredoxin-dependent redox system of the thermoacidophilic, aerobic archaeon sulfolobus sp. strain 7, a novel fes flavoprotein, which can reoxidize the reduced 7fe ferredoxin in vitro, has been purified and characterized (designated as ifp) using the cognate 7fe ferredoxin and 2-oxoacid:ferredoxin oxidoreductase, a key enzyme of the archaeal tricarboxylic acid cycle. ifp consists of three non-identical subunits with apparent molecular masses of 87, 32, and 22 kda, respectively, ... | 1995 | 7629091 |
| gene cloning, expression, and characterization of the sac7 proteins from the hyperthermophile sulfolobus acidocaldarius. | the genes for two sac7 dna-binding proteins, sac7d and sac7e, from the extremely thermophilic archaeon sulfolobus acidocaldarius have been cloned into escherichia coli and sequenced. the sac7d and sac7e open reading frames encode 66 amino acid (7608 da) and 65 amino acid (7469 da) proteins, respectively. southern blots indicate that these are the only two sac7 protein genes in s. acidocaldarius, each present as a single copy. sac7a, b, and c proteins appear to be carboxy-terminal modified sac7d ... | 1995 | 7632679 |
| the first nucleotide sequence of an archaeal elongation factor 1 beta gene. | an archaeal elongation factor 1 beta gene has been isolated for the first time from a sulfolobus solfataricus genomic library. the sequenced clone (869 bp) contained two open reading frames, one coding for a protein made of 91 amino acid residues (ssef-1 beta), the other one encoding a nonidentified product (orf 115). the amino acid sequences of segments at the n- and c-terminal of the translated ssef-1 beta were identical to those determined for the native protein. northern and southern analyse ... | 1995 | 7632739 |
| solution structure and dna-binding properties of a thermostable protein from the archaeon sulfolobus solfataricus. | the archaeon sulfolobus solfataricus expresses large amounts of a small basic protein, sso7d, which was previously identified as a dna-binding protein possibly involved in compaction of dna. we have determined the solution structure of sso7d. the protein consists of a triple-stranded anti-parallel beta-sheet onto which an orthogonal double-stranded beta-sheet is packed. this topology is very similar to that found in eukaryotic src homology-3 (sh3) domains. sso7d binds strongly (kd < 10 microm) t ... | 1994 | 7634092 |
| a multicopy plasmid of the extremely thermophilic archaeon sulfolobus effects its transfer to recipients by mating. | a plasmid of 45 kb, designated pnob8, was found in high copy number in a new heterotrophic sulfolobus isolate, nob8h2, from japan. dissemination of the plasmid occurred in six cultures of nine different sulfolobus strains when small amounts of the donor were added. these mixed cultures exhibited a high average copy number of the plasmid, between 20 and 40 per chromosome, and showed a marked growth retardation. horizontal transfer of pnob8 was proved by isolating transcipients from mating mixture ... | 1995 | 7635827 |
| glyceraldehyde-3-phosphate dehydrogenase in the hyperthermophilic archaeon sulfolobus solfataricus: characterization and significance in glucose metabolism. | glyceraldehyde-3-phosphate dehydrogenase in the archaeon sulfolobus solfataricus (ssgapd) has been purified 232 fold with an overall recovery of about 25%. the enzyme is a homomeric tetramer with an m(r) of 41 kda/subunit. it utilizes either nad+ or nadp+ as coenzyme but its affinity for the latter is about 50 fold higher. ssgapd activity is maximum at 87 degrees c. in the range 45-87 degrees c the arrhenius plot is linear and the activation energy is 55 kj/mol. the enzyme is thermostable, with ... | 1995 | 7663406 |
| molecular properties of glutamate dehydrogenase from the extreme thermophilic archaebacterium sulfolobus solfataricus. | this study is concerned with the structural characterization in solution of the glutamate dehydrogenase from the archaeon sulfolobus solfataricus. at neutral ph both alpha-helix and beta-sheet constitute the secondary structure of this enzyme, on the basis of circular dichroism. a complex, temperature dependent self-association equilibrium regulates the formation of the enzyme quaternary structure, which seems to be accompanied by a reversible structural change. at 25 degrees c the enzyme is mos ... | 1995 | 7669806 |
| nucleotide sequence of the 16s rrna gene from thermoacidophilic archaea sulfolobus acidocaldarius atcc33909. | | 1993 | 7680117 |
| characterization of the rnase p rna of sulfolobus acidocaldarius. | rnase p is the ribonucleoprotein enzyme that cleaves precursor sequences from the 5' ends of pre-trnas. in bacteria, the rna subunit is the catalytic moiety. eucaryal and archaeal rnase p activities copurify with rnas, which have not been shown to be catalytic. we report here the analysis of the rnase p rna from the thermoacidophilic archaeon sulfolobus acidocaldarius. the holoenzyme was highly purified, and extracted rna was used to identify the rnase p rna gene. the nucleotide sequence of the ... | 1993 | 7688716 |
| phylogenetic inference: linear invariants and maximum likelihood. | we develop a new statistical method for inferring phylogenies, based on a likelihood ratio test. this method does not require parameter constraints but does require identical evolutionary processes in the sites considered. another method of phylogenetic inference is the method of linear invariants, described by cavender (1989, molecular biology and evolution 6, 301-316), based on a notion of lake (1987, molecular biology and evolution 4, 167-191). we describe a sound mathematical basis for the u ... | 1993 | 7690255 |
| root of the universal tree of life based on ancient aminoacyl-trna synthetase gene duplications. | universal trees based on sequences of single gene homologs cannot be rooted. iwabe et al. [iwabe, n., kuma, k.-i., hasegawa, m., osawa, s. & miyata, t. (1989) proc. natl. acad. sci. usa 86, 9355-9359] circumvented this problem by using ancient gene duplications that predated the last common ancestor of all living things. their separate, reciprocally rooted gene trees for elongation factors and atpase subunits showed bacteria (eubacteria) as branching first from the universal tree with archaea (a ... | 1995 | 7708661 |
| nucleotide sequence of a gene cluster encoding ribosomal proteins in the thermoacidophilic crenarchaeon sulfolobus acidocaldarius. | a 1.6 kb genomic dna fragment derived from the extremely thermoacidophilic archaeon sulfolobus acidocaldarius (dsm 639) comprises four open reading frames. the sequence contains three genes encoding crenarchaeal ribosomal proteins with apparent molecular masses of 6.3 kda, 15.2 kda and 9.9 kda, which all represent strongly basic properties. these were identified by sequence comparison as rl46, rl31 and rl33. one open reading frame encodes a new polypeptide (22.1 kda, pi = 7.3) with no homology t ... | 1995 | 7711082 |
| dna-binding surface of the sso7d protein from sulfolobus solfataricus. | we have used nuclear magnetic resonance (n.m.r.) spectroscopy to identify the dna-binding surface of the abundant, small and basic protein sso7d from the hyperthermophilic archaebacterium sulfolobus solfataricus. the sso7d protein was previously found to bind strongly to double-stranded dna sequences and to protect dna from thermal denaturation, indicating that it might assume a similar function in vivo. several amide resonances in two-dimensional n.m.r. 1h, 15n correlation spectra of 15n-enrich ... | 1995 | 7723036 |
| purification and characterization of 3-isopropylmalate dehydrogenase from a thermoacidophilic archaebacterium sulfolobus sp. strain 7. | 3-isopropylmalate dehydrogenase was purified (about 2000-fold) to homogeneity for the first time from an archaebacterium, sulfolobus sp. strain 7. the enzyme showed an apparent molecular mass of about 110 kda by gel filtration and a single 36-kda polypeptide band on sds-page, suggesting tri- or tetrameric structure. the pi value was 6.9. the n-terminal amino acid sequence was similar to enzymes from other sources. the enzyme activity was greatly stimulated by the presence of mn2+, cd2+, mg2+, or ... | 1995 | 7557336 |
| on the use of nucleic acid sequences to infer early branchings in the tree of life. | simplifying assumptions made in various tree reconstruction methods--notably rate constancy among nucleotide sites, homogeneity, and stationarity of the substitutional processes--are clearly violated when nucleotide sequences are used to infer distant relationships. use of tree reconstruction methods based on such oversimplified assumptions can lead to misleading results, as pointed out by previous authors. in this paper, we made use of a (discretized) gamma distribution to account for variable ... | 1995 | 7739387 |
| archaea: narrowing the gap between prokaryotes and eukaryotes. | | 1995 | 7597025 |
| replacing the glutamate ligand in the structural zinc site of sulfolobus solfataricus alcohol dehydrogenase with a cysteine decreases thermostability. | the alcohol dehydrogenase gene from the thermophilic archaeum sulfolobus solfataricus has been subcloned and expressed in escherichia coli under the control of the t7 inducible promoter. the recombinant protein shows properties analogous to those of the native enzyme, including thermostability, despite the fact that e.coli does not post-translationally modify two lysine residues which are n-epsilon-methylated in the native enzyme. we constructed a 3-d model of the s.solfataricus alcohol dehydrog ... | 1995 | 7770449 |
| purification, cloning, and sequencing of archaebacterial pyrophosphatase from the extreme thermoacidophile sulfolobus acidocaldarius. | cytoplasmic pyrophosphatases are indispensible for the function of cellular bioenergetics. from the extreme thermoacidophilic archaeon sulfolobus acidocaldarius, situated at one of the lowest branches of the phylogenetic tree, a cytosolic pyrophosphatase has been isolated and purified 200-fold to electrophoretic homogeneity by combining ion-exchange and gel-exclusion chromatography. the native enzyme consists of a homotetramer of 71 kda apparent molecular mass; the subunit displays an apparent m ... | 1995 | 7771779 |
| cloning and functional analysis of the tata binding protein from sulfolobus shibatae. | archaea (formerly archaebacteria) comprise a domain of life that is phylogenetically distinct from both eucarya and bacteria. here we report the cloning of a gene from the archaeon sulfolobus shibatae that encodes a protein with strong homology to the tata binding protein (tbp) of eukaryotes. sulfolobus shibatae tbp is, however, almost as diverged from other archaeal tbps that have been cloned as it is from eukaryotic tbps. dna binding studies indicate that s.shibatae tbp recognizes tata-like a- ... | 1995 | 7784182 |
| primary structure of the thermosome from thermoplasma acidophilum. | the thermosome, a chaperonin from the archaebacterium thermoplasma acidophilum, consists of two subunits (m(r) 58,000 and 60,000) which assemble into a cylindrical complex of pseudo eight-fold rotational symmetry. the sequences of the two subunits are approximately 60% identical to each other and to tf55 from sulfolobus shibatae, and are 30-40% identical to the subunits of the tcp1 containing ring complex (tric) from the eukaryotic cytosol. a dendrogram of this family of chaperonins contains eig ... | 1995 | 7794526 |
| using protein synthesis inhibitors to establish the phylogenetic relationships of the sulfolobales order. | the sensitivity of the cell-free protein synthesis systems from acidanus brierleyi, acidianus infernus, and metallosphaera sedula, members of the archaeal order sulfolobales, to 40 antibiotics with different specificities has been studied. the sensitivity patterns were compared to those of sulfolobus solfataricus and other archaeal, bacterial, and eukaryotic systems. the comparative analysis shows that ribosomes from the sulfolobales are the most refractory to inhibitors of protein synthesis des ... | 1994 | 7807541 |
| which bacterium is the ancestor of the animal mitochondrial genome? | we present considerable data supporting the hypothesis that a sulfolobus- or mycoplasma-like endosymbiont, rather than an alpha-proteobacterium, is the ancestor of animal mitochondrial genomes. this hypothesis is based on pronounced similarities in oligonucleotide relative abundance extremes common to animal mtdna, sulfolobus, and mycoplasma capricolum and pronounced discrepancies of these relative abundance values with respect to alpha-proteobacteria. in addition, genomic dinucleotide relative ... | 1994 | 7809132 |
| purification and characterization of a maltase from the extremely thermophilic crenarchaeote sulfolobus solfataricus. | a soluble maltase (alpha-glucosidase) with an apparent subunit mass of 80 kda was purified to homogeneity from sulfolobus solfataricus. the enzyme liberates glucose from maltose and malto-oligomers. maximal activity was observed at 105 degrees c, with half-lives of 11 h (85 degrees c), 3.0 h (95 degrees c), and 2.75 h (100 degrees c). the enzyme was generally resistant to proteolysis and denaturants including aliphatic alcohols. n-propanol treatment at 85 degrees c increased both km and vmax for ... | 1995 | 7814342 |
| sard, a new protein isolated from the extremophile archaeon sulfolobus acidocaldarius, is a thermostable ribonuclease with dna-binding properties. | we have isolated the thermostable 9 kda sard-protein from sulfolobus acidocaldarius which exhibit rnase activity as well as dna-binding properties (sard). the amino acid composition and the sequence of the 16 n-terminal amino acids show similarities to different rnases as well as to dna-binding proteins from thermophilic archea. the rnase activity was demonstrated by 5s rrna degradation, thin layer chromatography and a zymogram. the temperature optimum for the rnase activity is 65 degrees c. the ... | 1995 | 7545905 |
| alternative form of the dicluster ferredoxin from the thermoacidophilic archaeon, sulfolobus sp. strain 7. | an alternative form of a 7fe dicluster-type ferredoxin (fd-b) with a different charge density was purified as a minor component from the aerobic and thermoacidophilic archaeon, sulfolobus sp. strain 7. comparison of its properties with those of native 7fe ferredoxin (fd-a), a major ferredoxin, was made in terms of the molecular properties, the absorption, circular dichroism and electron paramagnetic resonance spectral properties, and the reactivity coupled with the cognate 2-oxoacid:ferredoxin o ... | 1995 | 7826373 |
| the chaperonin from the archaeon sulfolobus solfataricus promotes correct refolding and prevents thermal denaturation in vitro. | we have isolated a chaperonin from the hyperthermophilic archaeon sulfolobus solfataricus based on its ability to inhibit the spontaneous refolding at 50 degrees c of dimeric s. solfataricus malic enzyme. the chaperonin, a 920-kda oligomer of 57-kda subunits, displays a potassium-dependent atpase activity with an optimum temperature at 80 degrees c. s. solfataricus chaperonin promotes correct refoldings of several guanidine hydrochloride-denatured enzymes from thermophilic and mesophilic sources ... | 1994 | 7833806 |
| ribosomal protein s1 in archaea. | cell extracts and ribosomes of thermoacidophilic and halophilic archaebacteria were analysed by immunoblotting to detect ribosomal protein s1 homologues. antisera to e. coli s1, the n-terminal ribosome binding domain (f2a) and the central and cooh-terminal nucleic acid binding domain (s1f1) of the protein were used. the results show that the thermoacidophilic archaebacterium sulfolobus acidocaldarius contains a protein with molecular weight of 66,000 that cross-reacts with anti-s1f1. however, th ... | 1994 | 7833831 |
| a seven-iron ferredoxin from the thermoacidophilic archaeon desulfurolobus ambivalens. | a seven-iron ferredoxin was isolated from aerobically grown cells of the hyperthermoacidophilic archaeon desulfurolobus ambivalens (dsm 3772). the protein is monomeric, with an apparent molecular mass of 15 kda and contains 7 iron atoms/molecule. the n-terminal sequence shows a large similarity (70% identity) with that of the ferredoxin isolated from the archaeon sulfolobus acidocaldarius. the epr characteristics in both the native (oxidized) and dithionite-reduced states of this protein allowed ... | 1995 | 7851403 |
| introduction of additional charges as an aid in protein purification: isolation of elongation factor 2 from sulfolobus acidocaldarius by preparative isoelectric focusing before and after adp-ribosylation. | diphtheria toxin catalyzes the adp-ribosylation of elongation factor 2 (ef-2) in eukaryotes and archae-bacteria. as the reaction is strictly ef-2 specific and introduces two negative charges into the molecule, the resulting shift in the isoelectric point (pi) by 0.2 ph units was used to establish a new purification method for ef-2 from sulfolobus acidocaldarius. the cells were lysed with dithiothreitol at ph 9 and ef-2 was purified by ammonium sulfate precipitation, gel filtration on sephadex g- ... | 1994 | 7858424 |
| sulredoxin: a novel iron-sulfur protein of the thermoacidophilic archaeon sulfolobus sp. strain 7 with a rieske-type [2fe-2s] center. | a novel pink [2fe-2s] protein has been purified from the cytosol fraction of the thermoacidophilic archaeon sulfolobus sp. strain 7 (originally named sulfolobus acidocaldarius 7) and called "sulredoxin." its absorption, circular dichroism, and electron paramagnetic resonance spectra suggest the presence of a rieske-type [2fe-2s] cluster (g-factors of 2.01, 1.91, and 1.79; average g-factor [gav] = 1.90) which is remarkably similar to that of thermus thermophilus respiratory rieske fes protein (j. ... | 1995 | 7730295 |