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C R Woese

Publications and source records attributed to C R Woese.

At least 19 recordsLinked to original sources
PubMed1992

A phylogenetic analysis of the myxobacteria: basis for their classification.

The primary sequence and secondary structural features of the 16S rRNA were compared for 12 different myxobacteria representing all the known cultivated genera. Analysis of these data show the myxobacteria to form a monophyletic grouping consisting of three distinct families, which lies within the delta subdivision of the purple bacterial phylum. The composition of the families is consistent with differences in cell and spore morphology, cell behavior, and pigment and secondary metabolite production but is not correlated with the morphological complexity of the fruiting bodies. The Nannocystis exedens lineage has evolved at an unusually rapid pace and its rRNA shows numerous primary and secondary structural idiosyncrasies.

Base Sequence↗
PubMed1992

The Ribosomal Database Project.

The Ribosomal Database Project (RDP) complies ribosomal sequences and related data, and redistributes them in aligned and phylogenetically ordered form to its user community. It also offers various software packages for handling, analyzing and displaying sequences. In addition, the RDP offers (or will offer) certain analytic services. At present the project is in an intermediate stage of development.

Base Sequence↗
PubMed1991

Description of the erythromycin-producing bacterium Arthrobacter sp. strain NRRL B-3381 as Aeromicrobium erythreum gen. nov., sp. nov.

Arthrobacter sp. strain NRRL B-3381T (T = type strain) is a nonmycelial, nonsporulating actinomycete that produces the macrolide antibiotic erythromycin. This bacterium differs in many ways from the type species of the genus Arthrobacter (Arthrobacter globiformis), suggesting that a taxonomic revision is appropriate. The G + C content of strain NRRL B-3381T DNA is 71 to 73 mol%, and the peptidoglycan of this organism contains LL-diaminopimelic acid. Evolutionary distance data obtained from 16S rRNA sequences identified NRRL B-3381T as the deepest branching member of the Nocardioides group of actinomycetes. The principal long-chain fatty acids which we identified that distinguished strain NRRL B-3381T from related G + C-rich bacteria were 10-methyloctadecanoic (tuberculosteric), octadecenoic, and hexadecanoic acids. These characteristics, together with phage typing and biochemical characteristics, form the basis for our recommendation that strain NRRL B-3381 should be the type strain of a new taxon, for which we propose the name Aeromicrobium erythreum.

Amino Acids↗
PubMed1991

Phylogenetic analysis of the spirochetes.

The 16S rRNA sequences were determined for species of Spirochaeta, Treponema, Borrelia, Leptospira, Leptonema, and Serpula, using a modified Sanger method of direct RNA sequencing. Analysis of aligned 16S rRNA sequences indicated that the spirochetes form a coherent taxon composed of six major clusters or groups. The first group, termed the treponemes, was divided into two subgroups. The first treponeme subgroup consisted of Treponema pallidum, Treponema phagedenis, Treponema denticola, a thermophilic spirochete strain, and two species of Spirochaeta, Spirochaeta zuelzerae and Spirochaeta stenostrepta, with an average interspecies similarity of 89.9%. The second treponeme subgroup contained Treponema bryantii, Treponema pectinovorum, Treponema saccharophilum, Treponema succinifaciens, and rumen strain CA, with an average interspecies similarity of 86.2%. The average interspecies similarity between the two treponeme subgroups was 84.2%. The division of the treponemes into two subgroups was verified by single-base signature analysis. The second spirochete group contained Spirochaeta aurantia, Spirochaeta halophila, Spirochaeta bajacaliforniensis, Spirochaeta litoralis, and Spirochaeta isovalerica, with an average similarity of 87.4%. The Spirochaeta group was related to the treponeme group, with an average similarity of 81.9%. The third spirochete group contained borrelias, including Borrelia burgdorferi, Borrelia anserina, Borrelia hermsii, and a rabbit tick strain. The borrelias formed a tight phylogenetic cluster, with average similarity of 97%. THe borrelia group shared a common branch with the Spirochaeta group and was closer to this group than to the treponemes. A single spirochete strain isolated fromt the shew constituted the fourth group. The fifth group was composed of strains of Serpula (Treponema) hyodysenteriae and Serpula (Treponema) innocens. The two species of this group were closely related, with a similarity of greater than 99%. Leptonema illini, Leptospira biflexa, and Leptospira interrogans formed the sixth and most deeply branching group. The average similarity within this group was 83.2%. This study represents the first demonstration that pathogenic and saprophytic Leptospira species are phylogenetically related. The division of the spirochetes into six major phylogenetic clusters was defined also by sequence signature elements. These signature analyses supported the conclusion that the spirochetes represent a monophylectic bacterial phylum.

Animals↗
PubMed1990

Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya.

Molecular structures and sequences are generally more revealing of evolutionary relationships than are classical phenotypes (particularly so among microorganisms). Consequently, the basis for the definition of taxa has progressively shifted from the organismal to the cellular to the molecular level. Molecular comparisons show that life on this planet divides into three primary groupings, commonly known as the eubacteria, the archaebacteria, and the eukaryotes. The three are very dissimilar, the differences that separate them being of a more profound nature than the differences that separate typical kingdoms, such as animals and plants. Unfortunately, neither of the conventionally accepted views of the natural relationships among living systems--i.e., the five-kingdom taxonomy or the eukaryote-prokaryote dichotomy--reflects this primary tripartite division of the living world. To remedy this situation we propose that a formal system of organisms be established in which above the level of kingdom there exists a new taxon called a "domain." Life on this planet would then be seen as comprising three domains, the Bacteria, the Archaea, and the Eucarya, each containing two or more kingdoms. (The Eucarya, for example, contain Animalia, Plantae, Fungi, and a number of others yet to be defined). Although taxonomic structure within the Bacteria and Eucarya is not treated herein, Archaea is formally subdivided into the two kingdoms Euryarchaeota (encompassing the methanogens and their phenotypically diverse relatives) and Crenarchaeota (comprising the relatively tight clustering of extremely thermophilic archaebacteria, whose general phenotype appears to resemble most the ancestral phenotype of the Archaea.

Archaea↗
PubMed1990

Higher order structural elements in ribosomal RNAs: pseudo-knots and the use of noncanonical pairs.

The data base of prokaryotic small subunit ribosomal RNAs alone now numbers more than 400 sequences, while that for the large subunit rRNAs numbers more than 70 when eukaryotic, mitochondrial, and plastid sequences are also included. Comparisons among these rRNA sequences reveal a number of positions that covary in composition, suggestive of higher order structural elements; 5 such structures are reported for the small subunit rRNA and 15 for the large subunit rRNA. While some of these are properly (small) secondary structural elements, the majority would have to be classified as more complex "tertiary" interactions, which in some cases bring together diverse areas in the secondary structural diagram. A number of the covariances are not of the canonical type, indicating non-Watson-Crick interactions.

Base Composition↗
PubMed1990

Architecture of ribosomal RNA: constraints on the sequence of "tetra-loops".

The four-base loops that cap many double-helical structures in rRNA (the so-called "tetra-loops") exhibit highly invariant to highly variable sequences depending upon their location in the molecule. However, in the vast majority of these cases the sequence of a tetra-loop is independent of its location and conforms to one of three general motifs, GNRA, UNCG, and (more rarely) CUUG. For the most frequently varying of the 16S rRNA tetra-loops, that at position 83 (Escherichia coli numbering), the three sequences CUUG, UUCG, and GCAA account for almost all examples encountered, and each of them has independently arisen at least a dozen times. The closing base pair of tetra-loop hairpins reflects the loop sequence, tending to be C.G for UUCG loops and G.C for CUUG loops.

Bacteria↗
PubMed1990

Structure detection through automated covariance search.

This paper summarizes our investigations into the computational detection of secondary and tertiary structure of ribosomal RNA. We have developed a new automated procedure that not only identifies potential secondary and tertiary structural interactions, but also provides the covariation evidence that supports the proposed bondings, and any counterevidence that can be detected in the known sequences. A small number of previously unknown higher-order structural features have been detected in individual RNA molecules (16S rRNA and 7S RNA) through the use of our automated procedure. We are systematically studying mitochondrial rRNA, seeking tertiary structure within 16S rRNA and quaternary structure between 16S and 23S rRNA. To test hypotheses suggested by an examination of our program's output, our colleagues in biology are sequencing key portions of the 23S ribosomal RNA for species in which the known 16S ribosomal RNA exhibits variation (from the dominant pattern) at the site of a proposed bonding. Our ultimate hope is that automated covariation analysis will contribute significantly to a refined picture of ribosomal structure.

Algorithms↗
PubMed1990

Assignment of Clostridium bryantii to Syntrophospora bryantii gen. nov., comb. nov. on the basis of a 16S rRNA sequence analysis of its crotonate-grown pure culture.

The Clostridium bryantii-Methanospirillum hungatei syntrophic coculture, grown on caproate, was adapted to grow on crotonate. Then, C. bryantii was isolated in pure culture from crotonate bottle plates. A 16S rRNA sequence analysis of the pure subculture revealed that, as a member of the gram-positive phylum, it was not closely related to any of the Clostridium species with which it was compared or to any of the other clusters in the gram-positive phylum with which it was compared. However, it was closely related to another syntrophic fatty acid-degrading bacterium, Syntrophomonas wolfei. On the basis of its phylogeny, physiology, and cell wall ultrastructure, we propose assignment of C. bryantii to Syntrophospora bryantii gen. nov., nov. comb.

Bacteriological Techniques↗
PubMed1989

Evidence for several higher order structural elements in ribosomal RNA.

Comparative analysis of small subunit ribosomal RNA sequences suggests the existence of two new higher order interactions: (i) a double-helical structure involving positions 505-507 and 524-526 (Escherichia coli numbering) and (ii) an interaction between the region of position 130 and the helix located approximately between positions 180 and 195. In the first of these, one of the strands of the helix exists in the bulge loop, and the other strand exists in the terminal loop of a previously recognized compound helix involving positions 500-545. Therefore, the new structure formally represents a pseudoknot. In the second, the insertion/deletion of a nucleotide in the vicinity of position 130 correlates with the length of the helix in the 180-195 region, the latter having a 3-base-pair stalk when the base in question is deleted and a stalk of approximately 10 pairs when it is inserted.

Animals↗
PubMed1989

Phylogenetic diversity of the Rickettsiae.

Small subunit rRNA sequences have been determined for representative strains of six species of the family Rickettsiaceae: Rickettsia rickettsii, Rickettsia prowazekii, Rickettsia typhi, Coxiella burnetii, Ehrlichia risticii, and Wolbachia persica. The relationships among these sequences and those of other eubacteria show that all members of the family Rickettsiaceae belong to the so-called purple bacterial phylum. The three representatives of the genus Rickettsia form a tight monophyletic cluster within the alpha subdivision of the purple bacteria. E. risticii also belongs to the alpha subdivision and shows a distant yet specific relationship to the genus Rickettsia. However, the family as a whole is not monophyletic, in that C. burnetii and W. persica are members of the gamma subdivision. The former appears to show a specific, but rather distant, relationship to the genus Legionella.

Bacteria↗
PubMed1989

A brief note concerning archaebacterial phylogeny.

Critical analysis of the recently proposed alternative to the normal archaebacterial tree, the new eocyte tree, shows that the latter's central topology, in which the eubacteria branch from an entirely different section of the unrooted archaebacterial tree than the eukaryotes, is consistent with an artifact. The effects of the alignment used and the particular composition of the sequence quartets analyzed to infer this tree are discussed in detail.

Archaea↗
PubMed1987

Comparative 16S rRNA oligonucleotide analyses and murein types of round-spore-forming bacilli and non-spore-forming relatives.

The phylogenetic incoherency of the genus Bacillus as presently described is demonstrated by analysis of both published and new data from comparative 16S rRNA cataloguing of nine Bacillus species and a number of related non-Bacillus taxa, i.e. Caryophanon latum, Filibacter limicola and Planococcus citreus. While the ellipsoidal-spore-forming bacilli, e.g. B. subtilis and allied species, formed a coherent cluster, the round-spore-forming bacilli showed a higher degree of relationship to the non-spore-forming organisms than these bacilli show among each other. Thus B. sphaericus clustered with C. latum, B. globisporus grouped with F. limicola, B. pasteurii with Sporosarcina ureae, and 'B. aminovorans' with P. citreus, respectively. These organisms formed two related subclusters which, in their phylogenetic depth, are comparable to that of the B. subtilis subline. With the exception of 'B. aminovorans', the 16S rRNA phylogeny was entirely consistent with the distribution of murein types. Even more distantly related to and grouping outside the main Bacillus cluster was B. stearothermophilus, which displayed a moderate relationship to Thermoactinomyces vulgaris. Taxonomic problems arising from the new insights into the intrageneric relationships of Bacillus are discussed.

Bacillus↗