Search results for "phylogenetics"
showing 10 items of 777 documents
Multilocus sequence analysis of the central clade of the genus Vibrio by using the 16S rRNA, recA, pyrH, rpoD, gyrB, rctB and toxR genes.
2009
The central clade of the genus Vibrio, also called the Vibrio core group, comprises six species that are tightly related (DNA–DNA reassociation values are very close to 70 % for most species pairs). Identification of novel strains to the species level within this group is troublesome and results are quite often dependent on the methodology employed. Therefore, this group represents an excellent framework to test the robustness of multilocus sequence analysis (MLSA) not only for inferring phylogeny but also as an identification tool without the need for DNA–DNA hybridization assays. The genes selected, 16S rRNA, recA, pyrH, rpoD, gyrB, rctB and toxR, were amplified by direct PCR from 44 Vibr…
Tropicibacter multivorans sp. nov., an aerobic alphaproteobacterium isolated from surface seawater.
2011
Strain MD5T, an aerobic marine alphaproteobacterium, was isolated from Mediterranean seawater at Malvarrosa beach, Valencia, Spain. The strain was characterized in a polyphasic study and was placed phylogenetically within the Roseobacter clade in the family Rhodobacteraceae . Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MD5T is related to Tropicibacter naphthalenivorans C02T, Phaeobacter inhibens T5T, P. gallaeciensis BS107T and P. daeponensis TF-218T, with 96.9, 96.2, 96.1 and 96.1 % sequence similarity, respectively. Phylogenetic analyses also showed that strain MD5T forms a stable clade only with T. naphthalenivorans C02T. Strain MD5T requires Na+ plus a diva…
Functional and genomic diversity of methylotrophic Rhodocyclaceae: description of Methyloversatilis discipulorum sp. nov.
2015
Three strains of methylotrophic Rhodocyclaceae (FAM1T, RZ18-153 and RZ94) isolated from Lake Washington sediment samples were characterized. Based on phylogenetic analysis of 16S rRNA gene sequences the strains should be assigned to the genus Methyloversatilis. Similarly to other members of the family, the strains show broad metabolic capabilities and are able to utilize a number of organic acids, alcohols and aromatic compounds in addition to methanol and methylamine. The main fatty acids were 16:1ω7c (49–59 %) and 16:0 (32–29 %). Genomes of all isolates were sequenced, assembled and annotated in collaboration with the DOE Joint Genome Institute (JGI). Genome comparison revealed that the s…
Pseudomonas lini sp. nov., a novel species from bulk and rhizospheric soils.
2002
The taxonomic position of eight fluorescent Pseudomonas strains isolated from bulk and rhizospheric soils, and from water was examined. These eight strains clustered in one phenon together with Pseudomomas mandelii (CFBP 4844T), but could still be differentiated from this type strain by four phenotypic features. The eight stains exhibited internal DNA-DNA hybridization values ranging from 60 to 100%, with deltaTm below 5 degrees C (3.9 and 4.3 degrees C) for the lowest values (60 and 66%). The percentages of hybridization with type or reference strains of other Pseudomonas species tested ranged from 12 to 60% (deltaTm = 5.5 degrees C), indicating that the eight isolates studied constituted …
Haliea mediterranea sp. nov., a marine gammaproteobacterium.
2010
Strain 7SM29T, an aerobic marine gammaproteobacterium isolated from seawater from Castellón, Spain, was characterized by classical phenotyping, chemotaxonomy and 16S rRNA gene sequence analysis. Strain 7SM29T was found to be closely related to strains in the genus Haliea and to Congregibacter litoralis KT71T, with which a genus-level cluster was formed within the NOR5/OM60 clade of the Gammaproteobacteria. Strain 7SM29T was a short, motile rod with a tuft of three polar flagella. The strain grew on marine agar and formed pale-yellow colonies. Strain 7SM29T required NaCl for growth, reduced nitrate to nitrite, degraded several polymers and showed a preference for organic acids and amino acid…
Diversity of stonefly hexamerins and implication for the evolution of insect storage proteins
2007
Hexamerins are large storage proteins of insects in the 500 kDa range that evolved from the copper-containing hemocyanins. Hexamerins have been found at high concentration in the hemolymph of many insect taxa, but have remained unstudied in relatively basal taxa. To obtain more detailed insight about early hexamerin evolution, we have studied hexamerins in stoneflies (Plecoptera). Stoneflies are also the only insects for which a functional hemocyanin is known to co-occur with hexamerins in the hemolymph. Here, we identified hexamerins in five plecopteran species and obtained partial cDNA sequences from Perla marginata (Perlidae), Nemoura sp. (Nemouridae), Taeniopteryx burksi (Taeniopterygid…
A novel member of an ancient superfamily: sponge (Geodia cydonium, Porifera) putative protein that features scavenger receptor cysteine-rich repeats
1997
Proteins featuring scavenger receptor cysteine-rich (SRCR) domains are prominent receptors known from vertebrates and from one phylum of invertebrates, the echinoderms. In the present study we report the first putative SRCR protein from the marine sponge Geodia cydonium (Porifera), a member of the lowest phylum of contemporary Metazoans. Two forms of SRCR molecules were characterized, which apparently represent alternative splicing of the same transcript. The long putative SRCR protein, of 1536 aa, features twelve SRCR repeats, a C-terminal transmembrane domain and a cytoplasmic tail. The sequence of the short form is identical with the long form except that it lacks a coding region near th…
Axial (apical-basal) expression of pro-apoptotic and pro-survival genes in the lake baikal demosponge Lubomirskia baicalensis.
2006
Like in all other Metazoa, also in sponges (Porifera) proliferation, differentiation, and death of cells are controlled by apoptotic processes, thus allowing the establishment of a Bauplan (body plan). The demosponge Lubomirskia baicalensis from the Lake Baikal is especially suitable to assess the role of the apoptotic molecules, since its grade of construction is highly elaborated into an encrusting base and branches composed of modules lined up along the apical-basal axis. The four cDNAs, ALG-2, BAK, MA-3, and Bcl-2, were isolated from this sponge species. The expression levels of these genes follow characteristic gradients. While the proapoptotic genes are highly expressed at the base of…
Termite Gut Symbiotic Archaezoa Are Becoming Living Metabolic Fossils
2003
ABSTRACT Over the course of several million years, the eukaryotic gut symbionts of lower termites have become adapted to a cellulolytic environment. Up to now it has been believed that they produce nutriments using their own cellulolytic enzymes for the benefit of their termite host. However, we have now isolated two endoglucanases with similar apparent molecular masses of approximately 36 kDa from the not yet culturable symbiotic Archaezoa living in the hindgut of the most primitive Australian termite, Mastotermes darwiniensis . The N-terminal sequences of these cellulases exhibited significant homology to cellulases of termite origin, which belong to glycosyl hydrolase family 9. The corre…
Evolutionary relationships of the metazoan βγ–crystallins, including that from the marine spongeGeodia cydonium
1997
beta gamma-crystallins are one major component of vertebrate lenses. Here the isolation and characterization of a cDNA, coding for the first beta gamma-crystallin molecule from an invertebrate species, the marine sponge Geodia cydonium, is described. The size of the transcript as determined by Northern blotting was 0.7 kb in length. The deduced amino acid sequence consists of 163 aa residues and comprises four repeated motifs which compose the two domains of the beta gamma-crystallin. Motif 3 contains the characteristic beta gamma-crystallin 'Greek key' motif signature, while in each of the three other repeats, one aa residue is replaced by an aa with the same physico-chemical property. The…