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1.
Eur J Cardiovasc Nurs ; 22(5): 472-481, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-36190843

RESUMO

AIMS: Electronic health (eHealth) sources have great potential to improve patients' access to health information for self-management of secondary prevention after percutaneous coronary intervention (PCI). It remains unclear, however, whether patients are health-related digitally active and whether they have sufficient eHealth literacy. This study aimed to determine the extent to which patients after PCI are health-related digitally active at baseline, 2 and 6 months after PCI, and to determine the association between patients' eHealth literacy and their health-related digital activity. METHODS AND RESULTS: This multicentre cohort study included patients at three large referral PCI centres in Norway (n = 1970). Data were collected from medical records, national registries, and patients' self-reports. The eHealth Literacy Scale (eHEALS) assessed patients' eHealth literacy. At baseline, 67% had used the internet to find health information. The mean eHEALS score was 25.71 (standard deviation 6.22), illustrating a lower level of eHealth literacy. There were substantial associations between eHealth literacy and use of the internet to find health information [coefficient 10.90, 95% confidence interval (CI) 8.05-14.57]. At the 2-month follow-up, there were substantial associations between baseline eHealth literacy and use of the internet to find information about health, prevention, illness, or treatment [odds ratio (OR) 1.19, 95% CI 1.14-1.24] and use of health applications (OR 1.15, 95% CI 1.08-1.22). CONCLUSION: This study provides evidence that patients' level of eHealth literacy after PCI is associated to how patients use, and can make use of, eHealth technology for health information. REGISTRATION: ClinicalTrials.gov (NCT03810612).


Assuntos
Letramento em Saúde , Intervenção Coronária Percutânea , Telemedicina , Humanos , Estudos de Coortes , Inquéritos e Questionários , Telemedicina/métodos , Estudos Transversais , Eletrônica , Tecnologia
2.
Genomics ; 91(4): 335-46, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18313895

RESUMO

We report the sequence of the Halobacterium salinarum strain R1 chromosome and its four megaplasmids. Our set of protein-coding genes is supported by extensive proteomic and sequence homology data. The structures of the plasmids, which show three large-scale duplications (adding up to 100 kb), were unequivocally confirmed by cosmid analysis. The chromosome of strain R1 is completely colinear and virtually identical to that of strain NRC-1. Correlation of the plasmid sequences revealed 210 kb of sequence that occurs only in strain R1. The remaining 350 kb shows virtual sequence identity in the two strains. Nevertheless, the number and overall structure of the plasmids are largely incompatible. Also, 20% of the protein sequences differ despite the near identity at the DNA sequence level. Finally, we report genome-wide mobility data for insertion sequences from which we conclude that strains R1 and NRC-1 originate from the same natural isolate. This exemplifies evolution in the laboratory.


Assuntos
Evolução Biológica , Genoma Arqueal , Halobacterium salinarum/genética , Sequência de Aminoácidos , Proteínas Arqueais/química , Proteínas Arqueais/genética , Cromossomos de Archaea , Dados de Sequência Molecular , Plasmídeos , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
3.
Photochem Photobiol Sci ; 4(9): 688-93, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16121278

RESUMO

To properly respond to changes in fluency conditions, Nature has developed a variety of photosensors that modulate gene expression, enzyme activity and/or motility. Dedicated types have evolved, which can be classified in six families: rhodopsins, phytochromes, xanthopsins, cryptochromes, phototropins and BLUF-proteins. The photochemistry of the first three families is based on cis/trans isomerization of an ethylene bond. Surprisingly, the latter three all use flavin as their chromophore, but each with very different photochemistry. In this contribution we will discuss the molecular basis of signal generation in a xanthopsin (Photoactive Yellow Protein (PYP) from Halorhodospira halophila), a photoreceptor for negative phototaxis, and in a BLUF protein (AppA from Rhodobacter sphaeroides), a transcriptional anti-repressor. PYP is activated through trans/cis isomerization of the 7,8-vinyl bond of its 4-hydroxycinnamic acid chromophore. This initiates a photocycle with multiple intermediates, like pB, which is formed after intramolecular proton transfer. The negative charge thus formed in the interior of the protein triggers formation of a partially unfolded signaling state. For AppA much less is known about the underlying photochemistry. Available evidence suggests that it is based on a light-induced change in the hydrogen-bonding of its flavin chromophore and/or a change in hydrophobic stacking between the flavin and/or nearby aromatic amino acids like Y 21. A signaling state is formed within microseconds, which recovers with a rate of approximately 10(-3) s(-1). The change in conformation between receptor- and signaling-state in AppA, however, appear to be minute as compared to those in PYP. Here we review the underlying chemistry in the various steps of the photocycle of these two photoreceptor proteins and provide new data on their mechanism and function.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/fisiologia , Flavoproteínas/química , Flavoproteínas/fisiologia , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/fisiologia , Sequência de Aminoácidos , Dados de Sequência Molecular , Fotoquímica , Homologia de Sequência de Aminoácidos , Transdução de Sinais/fisiologia
4.
Opt Lett ; 26(9): 641-3, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18040409

RESUMO

We present an ultrahigh-resolution saturation spectrometer based on a line-tunable carbon monoxide laser near 60 THz (lambda = 5 microm). A spectral resolution of 14 kHz (Dnu/nu = 2.3 x 10(-10)) for CO fundamental-band transitions was achieved, which improves on earlier results by one order of magnitude. A frequency-locking scheme using tunable microwave sidebands provides tunability and absolute frequency control of the CO laser on the kilohertz. Transit-time broadening and pressure broadening of the observed transitions are significantly reduced by use of expanded laser beams in a 24-m absorption cell at pressures down to 0.0 1Pa. The new spectrometer is suitable for the study of saturation line shapes and the development of a new generation of frequency standards in the 60-THz region.

5.
J Mol Spectrosc ; 204(2): 281-285, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11148097

RESUMO

By using tunable microwave sidebands added to CO-laser lines, we have made more sub-Doppler heterodyne frequency measurements on OCS. Three new rotational transitions have been measured for each of three absorption bands, 10(0)0-00(0)0, 02(0)1-00(0)0, and 03(1)1-01(1)0. The absolute uncertainties of the measurements are on the order of +/-25 kHz. New calibration tables are given for the region 1860-1925 and 2020-2085 cm(-1) based on the most recent OCS measurements. Copyright 2000 Academic Press.

6.
J Mol Evol ; 49(4): 524-37, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10486009

RESUMO

A global alignment of EF-G(2) sequences was corrected by reference to protein structure. The selection of characters eligible for construction of phylogenetic trees was optimized by searching for regions arising from the artifactual matching of sequence segments unique to different phylogenetic domains. The spurious matchings were identified by comparing all sections of the global alignment with a comprehensive inventory of significant binary alignments obtained by BLAST probing of the DNA and protein databases with representative EF-G(2) sequences. In three discrete alignment blocks (one in domain II and two in domain IV), the alignment of the bacterial sequences with those of Archaea-Eucarya was not retrieved by database probing with EF-G(2) sequences, and no EF-G homologue of the EF-2 sequence segments was detected by using partial EF-G(2) sequences as probes in BLAST/FASTA searches. The two domain IV regions (one of which comprises the ADP-ribosylatable site of EF-2) are almost certainly due to the artifactual alignment of insertion segments that are unique to Bacteria and to Archaea-Eucarya. Phylogenetic trees have been constructed from the global alignment after deselecting positions encompassing the unretrieved, spuriously aligned regions, as well as positions arising from misalignment of the G' and G" subdomain insertion segments flanking the "fifth" consensus motif of the G domain (AE varsson, 1995). The results show inconsistencies between trees inferred by alternative methods and alternative (DNA and protein) data sets with regard to Archaea being a monophyletic or paraphyletic grouping. Both maximum-likelihood and maximum-parsimony methods do not allow discrimination (by log-likelihood difference and difference in number of inferred substitutions) between the conflicting (monophyletic vs. paraphyletic Archaea) topologies. No specific EF-2 insertions (or terminal accretions) supporting a crenarchaeal-eucaryal clade are detectable in the new EF-G(2) sequence alignment.


Assuntos
Archaea/genética , Evolução Molecular , Fator G para Elongação de Peptídeos/genética , Filogenia , Sequência de Aminoácidos , Animais , Bactérias/genética , Bases de Dados Factuais , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
7.
J Mol Spectrosc ; 190(1): 91-100, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9645928

RESUMO

We present sub-Doppler heterodyne frequency measurements on 10 rovibrational transitions of carbonyl sulfide (OCS) between 2894 and 2910 cm-1. The measurements were made using a CO overtone laser which had limited tuneability through the generation of microwave sidebands in a CdTe crystal. With this technique the laser frequencies were shifted to the desired OCS transition frequencies. The transition frequencies could be measured with uncertainties less than 30 kHz (Deltanu/nu = 3 x 10(-10)) by frequency offset-locking the CO overtone laser to combination frequencies of two saturation-stabilized CO2 laser standards. The measured transition frequencies of OCS were combined with previous sub-Doppler, Fourier transform, and microwave measurements to recalculate improved calibration tables for the 10(0)1-00(0)0, 11(1e)1-01(1e)0, and 11(1f)1-01(1f)0 bands. These tables are suitable for the calibration of infrared spectrometers in the 87 THz region (near 2900 cm-1). Copyright 1998 Academic Press.

8.
Opt Lett ; 23(1): 58-60, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18084411

RESUMO

We report a source of tunable laser radiation for high-precision molecular spectroscopy in the 2.6- 4.1-microm spectral region. Laser light from a CO overtone laser is mixed with microwaves, generating tunable sidebands of ~1 mW of power. We achieve very high absolute frequency accuracy by frequency-offset locking the CO laser to a CO(2) laser secondary frequency standard. The uncertainty of the laser frequency is less than 30 kHz (Dnu/nu=3x10(-10)) , and the laser linewidth is of the order of 100 kHz. This tunable and ultrastable laser system is suitable for very accurate molecular spectroscopy and metrology in a most interesting wavelength region. We demonstrate an application of the system to saturated-absorption spectroscopy of a rovibrational transition of carbonyl sulfide.

9.
Eur J Biochem ; 233(1): 227-37, 1995 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7588750

RESUMO

The gene coding for the 3-phosphoglycerate kinase (EC 2.7.2.3) of Pyrococcus woesei was cloned and sequenced. The gene sequence comprises 1230 bp coding for a polypeptide with the theoretical M(r) of 46,195. The deduced protein sequence exhibits a high similarity (46.1% and 46.6% identity) to the other known archaeal 3-phosphoglycerate kinases of Methanobacterium bryantii and Methanothermus fervidus [Fabry, S., Heppner, P., Dietmaier, W. & Hensel, R. (1990) Gene 91, 19-25]. By comparing the 3-phosphoglycerate kinase sequences of the mesophilic and the two thermophilic Archaea, trends in thermoadaptation were confirmed that could be deduced from comparisons of glyceraldehyde-3-phosphate dehydrogenase sequences from the same organisms [Zwickl, P., Fabry, S., Bogedain, C., Haas, A. & Hensel, R. (1990) J. Bacteriol. 172, 4329-4338]. With increasing temperature the average hydrophobicity and the portion of aromatic residues increases, whereas the chain flexibility as well as the content in chemically labile residues (Asn, Cys) decreases. To study the phenotypic properties of the 3-phosphoglycerate kinases from thermophilic Archaea in more detail, the 3-phosphoglycerate kinase genes from P. woesei and M. fervidus were expressed in Escherichia coli. Comparisons of kinetic and molecular properties of the enzymes from the original organisms and from E. coli indicate that the proteins expressed in the mesophilic host are folded correctly. Besides their higher thermostability according to their origin from hyperthermophilic organisms, both enzymes differ from their bacterial and eucaryotic homologues mainly in two respects. (a) The 3-phosphoglycerate kinases from P. woesei and M. fervidus are homomeric dimers in their native state contrary to all other known 3-phosphoglycerate kinases, which are monomers including the enzyme from the mesophilic Archaeum M. bryantii. (b) Monovalent cations are essential for the activity of both archaeal enzymes with K+ being significantly more efficient than Na+. For the P. woesei enzyme, non-cooperative K+ binding with an apparent Kd (K+) of 88 mM could be determined by kinetic analysis, whereas for the M. fervidus 3-phosphoglycerate kinase the K+ binding is rather complex: from the fitting of the saturation data, non-cooperative binding sites with low selectivity for K+ and Na+ (apparent Kd = 270 mM) and at least three cooperative and highly specific K+ binding sites/subunit are deduced. At the optimum growth temperature of P. woesei (100 degrees C) and M. fervidus (83 degrees C), the 3-phosphoglycerate kinases show half-lives of inactivation of only 28 min and 44 min, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Archaea/enzimologia , Archaea/genética , Euryarchaeota/enzimologia , Euryarchaeota/genética , Genes Bacterianos , Fosfoglicerato Quinase/genética , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , Primers do DNA/genética , DNA Bacteriano/genética , Escherichia coli/genética , Expressão Gênica , Cinética , Dados de Sequência Molecular , Estrutura Molecular , Peso Molecular , Fosfoglicerato Quinase/química , Fosfoglicerato Quinase/metabolismo , Filogenia , Conformação Proteica , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos
10.
Proc Natl Acad Sci U S A ; 91(8): 3255-9, 1994 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-8159735

RESUMO

The EF-2 coding genes of the Archaea Pyrococcus woesei and Desulfurococcus mobilis were cloned and sequenced. Global phylogenies were inferred by alternative tree-making methods from available EF-2(G) sequence data and contrasted with phylogenies constructed from the more conserved but shorter EF-1 alpha(Tu) sequences. Both the monophyly (sensu Hennig) of Archaea and their subdivision into the kingdoms Crenarchaeota and Euryarchaeota are consistently inferred by analysis of EF-2(G) sequences, usually at a high bootstrap confidence level. In contrast, EF-1 alpha(Tu) phylogenies tend to be inconsistent with one another and show low bootstrap confidence levels. While evolutionary distance and DNA maximum parsimony analyses of EF-1 alpha(Tu) sequences do show archaeal monophyly, protein parsimony and DNA maximum-likelihood analyses of these data do not. In no case, however, do any of the tree topologies inferred from EF-1 alpha(Tu) sequence analyses receive significant bootstrap support.


Assuntos
Fatores de Alongamento de Peptídeos/genética , Filogenia , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Funções Verossimilhança , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos , Fator G para Elongação de Peptídeos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
11.
Nucleic Acids Res ; 21(21): 4904-8, 1993 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8177738

RESUMO

An improved purification procedure for Thermotoga maritima RNA-polymerase holoenzyme was developed. The enzyme is highly active with poly dAT or T7 phage DNA as template. DNA gyrase was found to be a side product of this RNA-polymerase purification. The genes for the large subunits beta and beta' of RNA-polymerase were cloned and sequenced. The phylogenetic position of T.maritima within the bacterial domain was determined by various methods. It is the lowest bacterial offspring but slightly higher than the chloroplasts.


Assuntos
RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Bactérias Anaeróbias Gram-Negativas/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , DNA Bacteriano , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Bactérias Anaeróbias Gram-Negativas/classificação , Bactérias Anaeróbias Gram-Negativas/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Filogenia , Homologia de Sequência de Aminoácidos
12.
Mol Gen Genet ; 237(3): 334-42, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8483447

RESUMO

We present evidence for the existence of a conservative site-specific recombination system in Archaea by demonstrating integrative recombination of Sulfolobus shibatae virus SSV1 DNA with the host chromosome, catalysed by the SSV1-encoded integrase in vitro. The putative int gene of SSV1 was expressed in Escherichia coli yielding a protein of about 39 kDa. This protein alone efficiently recombined linear DNA substrates containing chromosomal (attA) and viral (attP) attachment sites; recombination with either negatively or positively supercoiled SSV1 DNA was less efficient. Intermolecular attA x attA and attP x attP recombination was also promoted by the SSV integrase. The invariant 44 bp "common attachment core" present in all att sites contained sufficient information to allow recombination, whilst the flanking sequences effected the efficiency. These features clearly distinguish the SSV1--encoded site--specific recombination system from others and make it suitable for the study of regulatory mechanisms of SSV1 genome--host chromosome interaction and investigations of the evolution of the recombination machinery.


Assuntos
Bacteriófagos/genética , DNA Nucleotidiltransferases/genética , Recombinação Genética , Sulfolobus/genética , Sequência de Bases , Southern Blotting , DNA Bacteriano/genética , DNA de Cadeia Simples , DNA Viral/genética , Teste de Complementação Genética , Genoma Bacteriano , Integrases , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Especificidade por Substrato , Integração Viral
13.
Virology ; 190(1): 45-54, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1529545

RESUMO

The complete nucleotide sequence of the plasmid p phi HL, composing the central 12,041-bp L-region from the temperate phage phi H of Halobacterium salinarium is presented. Transcripts mapped to the p phi HL and the L-region produced under immune conditions, under lytic growth or constitutively, are described. The sequences upstream of the transcription start points show homology to the consensus sequence for archaeal (formerly archaebacterial) promoters. Lytic transcription is shown to be strictly time-dependent, with an early gene product required for the expression of late genes.


Assuntos
Bacteriófagos/genética , DNA Viral/genética , Halobacterium/genética , Plasmídeos , Transcrição Gênica , Sequência de Bases , Northern Blotting , Southern Blotting , DNA Viral/química , Cinética , Lisogenia , Dados de Sequência Molecular , Mutação , Mapeamento por Restrição
14.
J Mol Evol ; 34(5): 396-405, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1602493

RESUMO

Phylogenies were inferred from both the gene and the protein sequences of the translational elongation factor termed EF-2 (for Archaea and Eukarya) and EF-G (for Bacteria). All treeing methods used (distance-matrix, maximum likelihood, and parsimony), including evolutionary parsimony, support the archaeal tree and disprove the "eocyte tree" (i.e., the polyphyly and paraphyly of the Archaea). Distance-matrix trees derived from both the amino acid and the DNA sequence alignments (first and second codon positions) showed the Archaea to be a monophyletic-holophyletic grouping whose deepest bifurcation divides a Sulfolobus branch from a branch comprising Methanococcus, Halobacterium, and Thermoplasma. Bootstrapped distance-matrix treeing confirmed the monophyly-holophyly of Archaea in 100% of the samples and supported the bifurcation of Archaea into a Sulfolobus branch and a methanogen-halophile branch in 97% of the samples. Similar phylogenies were inferred by maximum likelihood and by maximum (protein and DNA) parsimony. DNA parsimony trees essentially identical to those inferred from first and second codon positions were derived from alternative DNA data sets comprising either the first or the second position of each codon. Bootstrapped DNA parsimony supported the monophyly-holophyly of Archaea in 100% of the bootstrap samples and confirmed the division of Archaea into a Sulfolobus branch and a methanogen-halophile branch in 93% of the bootstrap samples. Distance-matrix and maximum likelihood treeing under the constraint that branch lengths must be consistent with a molecular clock placed the root of the universal tree between the Bacteria and the bifurcation of Archaea and Eukarya. The results support the division of Archaea into the kingdoms Crenarchaeota (corresponding to the Sulfolobus branch and Euryarchaeota). This division was not confirmed by evolutionary parsimony, which identified Halobacterium rather than Sulfolobus as the deepest offspring within the Archaea.


Assuntos
Archaea/genética , Proteínas de Bactérias/genética , Classificação , Fatores de Alongamento de Peptídeos/genética , Filogenia , Sequência de Aminoácidos , Animais , Archaea/classificação , Bactérias/classificação , Bactérias/genética , Cricetinae , DNA/genética , Dictyostelium/classificação , Dictyostelium/genética , Drosophila melanogaster/classificação , Drosophila melanogaster/genética , Funções Verossimilhança , Mesocricetus/classificação , Mesocricetus/genética , Dados de Sequência Molecular , Fator 2 de Elongação de Peptídeos , Fator G para Elongação de Peptídeos , Alinhamento de Sequência , Software , Especificidade da Espécie
17.
Proc Natl Acad Sci U S A ; 89(1): 407-10, 1992 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-1729711

RESUMO

The gene encoding component H of the DNA-dependent RNA polymerase (RNAP, EC 2.7.7.6) of Sulfolobus acidocaldarius has been identified by comparison of the amino acid sequence with the derived amino acid sequence of an open reading frame (ORF88) in the RNAP operon. Corresponding genes were identified in Halobacterium halobium and were cloned and sequenced from Thermococcus celer and Methanococcus vannielii. All these rpoH genes are situated between the promoters of the RNAP operons and the corresponding rpoB and rpoB2 genes. The archaeal H subunits show high sequence similarity to each other and to the C-terminal portions of the largest of four subunits shared by all three specialized nuclear RNAPs. These correlations are further evidence for the striking similarity between archaeal and eucaryal RNAP structures and transcription systems.


Assuntos
Archaea/enzimologia , RNA Polimerases Dirigidas por DNA/química , Genes Bacterianos , Sequência de Aminoácidos , Archaea/genética , Sequência de Bases , Evolução Biológica , RNA Polimerases Dirigidas por DNA/genética , Dados de Sequência Molecular , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Alinhamento de Sequência
18.
Virology ; 185(1): 242-50, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1926776

RESUMO

The DNA sequence of the Sulfolobus shibatae virus SSV1 is the first complete sequence of an archaebacterial virus genome. The viral DNA is a closed double-stranded DNA circle of 15465 bp. The features of the sequence, the positions of all 11 transcripts, the three characterized proteins, and the open reading frames are described.


Assuntos
Bacteriófagos/genética , DNA Circular/genética , DNA Viral/genética , Genoma Viral , Sulfolobus/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular/métodos , DNA Circular/isolamento & purificação , DNA Viral/isolamento & purificação , Escherichia coli/genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica , Proteínas Virais/genética
19.
J Mol Evol ; 33(4): 332-42, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1723106

RESUMO

The gene encoding elongation factor 1 alpha (EF-1 alpha, 1290 bp) of the ultrathermophilic, sulfur-reducing archaeote Pyrococcus woesei was localized within a Bg/II fragment of chromosomal DNA. Sequence analysis showed that the EF-1 alpha gene is the upstream unit of a three-gene cluster comprising the genes for ribosomal protein S10 (306 bp) and transfer RNAser (GGA). The three genes follow each other immediately in the order EF-1 alpha.S10.tRNA(ser) after a putative promoter located 55 bp upstream of the EF-1 alpha gene. Alignment of the derived EF-1 alpha sequence with the corresponding sequences from Eukarya, Bacteria/organelles, and with available archaeal sequences (Sulfolobus, Thermococcus, Methanococcus, Halobacterium) showed that Pyrococcus EF-1 alpha is highly homologous (89% identity) to Thermococcus celer EF-1 alpha, both being strikingly more similar to eukaryotic EF-1 alpha than to bacterial EF-Tu. Unrooted dendrograms computed from aligned sequences by distance matrix and DNA parsimony methods, including evolutionary parsimony, showed the Archaea to be a monophyletic-holophyletic cluster closer to Eukarya than to Bacteria. Both distance matrix and DNA parsimony--although not evolutionary parsimony--support the partition of the known archaeal lineages between the kingdoms Crenarchaeota and Euryarchaeota, and the affiliation of the Pyrococcus-Thermococcus lineage to the Euryarchaeota, of which it is the most primitive offspring. A closer relation of Pyrococcus to Euryarchaeota than to Crenarchaeota was also inferred from sequence analysis of S10 ribosomal proteins.


Assuntos
Archaea/genética , Fatores de Alongamento de Peptídeos/genética , Filogenia , Sequência de Aminoácidos , Archaea/classificação , Sequência de Bases , Clonagem Molecular , DNA Bacteriano , Ligação Genética , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos , Fator Tu de Elongação de Peptídeos/genética , RNA Bacteriano , Proteínas Ribossômicas/genética , Alinhamento de Sequência
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