Complete genome sequence of Nitratifractor salsuginis type strain (E9I37-1)

Nitratifractor salsuginis Nakagawa et al. 2005 is the type species of the genus Nitratifractor, a member of the family Nautiliaceae. The species is of interest because of its high capacity for nitrate reduction via conversion to N(2) through respiration, which is a key compound in plant nutrition. The strain is also of interest because it represents the first mesophilic and facultatively anaerobic member of the Epsilonproteobacteria reported to grow on molecular hydrogen. This is the first completed genome sequence of a member of the genus Nitratifractor and the second sequence from the family Nautiliaceae. The 2,101,285 bp long genome with its 2,121 protein-coding and 54 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of Deinococcus maricopensis type strain (LB-34)

Deinococcus maricopensis (Rainey and da Costa 2005) is a member of the genus Deinococcus, which is comprised of 44 validly named species and is located within the deeply branching bacterial phylum Deinococcus-Thermus. Strain LB-34(T) was isolated from a soil sample from the Sonoran Desert in Arizona. Various species of the genus Deinococcus are characterized by extreme radiation resistance, with D. maricopensis being resistant in excess of 10 kGy. Even though the genomes of three Deinococcus species, D. radiodurans, D. geothermalis and D. deserti, have already been published, no special physiological characteristic is currently known that is unique to this group. It is therefore of special interest to analyze the genomes of additional species of the genus Deinococcus to better understand how these species adapted to gamma- or UV ionizing-radiation. The 3,498,530 bp long genome of D. maricopensis with its 3,301 protein-coding and 66 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of the extremely halophilic Halanaerobium praevalens type strain (GSL)

Halanaerobium praevalens Zeikus et al. 1984 is the type species of the genus Halanaerobium, which in turn is the type genus of the family Halanaerobiaceae. The species is of interest because it is able to reduce a variety of nitro-substituted aromatic compounds at a high rate, and because of its ability to degrade organic pollutants. The strain is also of interest because it functions as a hydrolytic bacterium, fermenting complex organic matter and producing intermediary metabolites for other trophic groups such as sulfate-reducing and methanogenic bacteria. It is further reported as being involved in carbon removal in the Great Salt Lake, its source of isolation. This is the first completed genome sequence of a representative of the genus Halanaerobium and the second genome sequence from a type strain of the family Halanaerobiaceae. The 2,309,262 bp long genome with its 2,110 protein-coding and 70 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of the hyperthermophilic chemolithoautotroph Pyrolobus fumarii type strain (1A)

Pyrolobus fumarii Blöchl et al. 1997 is the type species of the genus Pyrolobus, which belongs to the crenarchaeal family Pyrodictiaceae. The species is a facultatively microaerophilic non-motile crenarchaeon. It is of interest because of its isolated phylogenetic location in the tree of life and because it is a hyperthermophilic chemolithoautotroph known as the primary producer of organic matter at deep-sea hydrothermal vents. P. fumarii exhibits currently the highest optimal growth temperature of all life forms on earth (106°C). This is the first completed genome sequence of a member of the genus Pyrolobus to be published and only the second genome sequence from a member of the family Pyrodictiaceae. Although Diversa Corporation announced the completion of sequencing of the P. fumarii genome on September 25, 2001, this sequence was never released to the public. The 1,843,267 bp long genome with its 1,986 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of Calditerrivibrio nitroreducens type strain (Yu37-1)

Calditerrivibrio nitroreducens Iino et al. 2008 is the type species of the genus Calditerrivibrio. The species is of interest because of its important role in the nitrate cycle as nitrate reducer and for its isolated phylogenetic position in the Tree of Life. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the third complete genome sequence of a member of the family Deferribacteraceae. The 2,216,552 bp long genome with its 2,128 protein-coding and 50 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of Riemerella anatipestifer type strain (ATCC 11845)

Riemerella anatipestifer (Hendrickson and Hilbert 1932) Segers et al. 1993 is the type species of the genus Riemerella, which belongs to the family Flavobacteriaceae. The species is of interest because of the position of the genus in the phylogenetic tree and because of its role as a pathogen of commercially important avian species worldwide. This is the first completed genome sequence of a member of the genus Riemerella. The 2,155,121 bp long genome with its 2,001 protein-coding and 51 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Complete genome sequence of Cellulophaga algicola type strain (IC166)

Cellulophaga algicola Bowman 2000 belongs to the family Flavobacteriaceae within the phylum 'Bacteroidetes' and was isolated from Melosira collected from the Eastern Antarctic coastal zone. The species is of interest because its members produce a wide range of extracellular enzymes capable of degrading proteins and polysaccharides with temperature optima of 20-30°C. This is the first completed genome sequence of a member of the genus Cellulophaga. The 4,888,353 bp long genome with its 4,285 protein-coding and 62 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Generation and Characterization of a genetic zebrafish model of SMA carrying the human SMN2 gene

Background

Animal models of human diseases are essential as they allow analysis of the disease process at the cellular level and can advance therapeutics by serving as a tool for drug screening and target validation. Here we report the development of a complete genetic model of spinal muscular atrophy (SMA) in the vertebrate zebrafish to complement existing zebrafish, mouse, and invertebrate models and show its utility for testing compounds that alter SMN2 splicing.

Results

The human motoneuron disease SMA is caused by low levels, as opposed to a complete absence, of the survival motor neuron protein (SMN). To generate a true model of SMA in zebrafish, we have generated a transgenic zebrafish expressing the human SMN2 gene (hSMN2), which produces only a low amount of full-length SMN, and crossed this onto the smn ^-/- background. We show that human SMN2 is spliced in zebrafish as it is in humans and makes low levels of SMN protein. Moreover, we show that an antisense oligonucleotide that enhances correct hSMN2 splicing increases full-length hSMN RNA in this model. When we placed this transgene on the smn mutant background it rescued the neuromuscular presynaptic SV2 defect that occurs in smn mutants and increased their survival.

Conclusions

We have generated a transgenic fish carrying the human hSMN2 gene. This gene is spliced in fish as it is in humans and mice suggesting a conserved splicing mechanism in these vertebrates. Moreover, antisense targeting of an intronic splicing silencer site increased the amount of full length SMN generated from this transgene. Having this transgene on the smn mutant fish rescued the presynaptic defect and increased survival. This model of zebrafish SMA has all of the components of human SMA and can thus be used to understand motoneuron dysfunction in SMA, can be used as an vivo test for drugs or antisense approaches that increase full-length SMN, and can be developed for drug screening.     

Cyclical parthenogenetic reproduction in the Russian wheat aphid (Hemiptera: Aphididae) in the United States: sexual reproduction and its outcome on biotypic diversity

In 1986, the Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), became an invasive species of United States. Nearly 20 yr later, new biotypes appeared that were capable of overcoming most sources of resistance and became a renewed threat to wheat, Triticum aestivum L., production. Cyclical (CP) and obligate (OP) parthenogenesis enables aphids to both adapt to changing environments and exploit host resources. We documented these forms of reproduction for Russian wheat aphid in wheat and wild grasses in the Central Great Plains and Rocky Mountain regions during falls 2004-2009. Colonies from sample sites also were held under unheated greenhouse conditions and observed for the presence of sexual morphs and eggs through the winter. Russian wheat aphid populations were mainly OP and attempted to overwinter as adults, regardless of region sampled. A few populations contained oviparae but no males (gynocyclic) and were not specific to any particular region. Observation of the Russian wheat aphid colonies under greenhouse conditions failed to produce males or eggs. In spring 2007, CP was confirmed in a small population of Russian wheat aphid that eclosed from eggs (fundatricies) on wild grasses and wheat near Dove Creek, CO, in the Colorado Plateau region where other aphid species undergo CP. Lineages from ninety-three fundatricies were screened against 16 resistant and susceptible cereal entries to determine their biotypic classification. A high degree of biotypic diversity (41.4%) was detected in this population. Although CP was a rare in Russian wheat aphid populations, genetic recombination during the sexual cycle creates new biotypes and can have significant effects on population genetics.     

Crystal structure of a new benzoic acid inhibitor of influenza neuraminidase bound with a new tilt induced by overpacking subsite C6

Background

The quaternary structure of eukaryotic NADH:ubiquinone oxidoreductase (complex I), the largest complex of the oxidative phosphorylation, is still mostly unresolved. Furthermore, it is unknown where transiently bound assembly factors interact with complex I. We therefore asked whether the evolution of complex I contains information about its 3D topology and the binding positions of its assembly factors. We approached these questions by correlating the evolutionary rates of eukaryotic complex I subunits using the mirror-tree method and mapping the results into a 3D representation by multidimensional scaling.

Results

More than 60% of the evolutionary correlation among the conserved seven subunits of the complex I matrix arm can be explained by the physical distance between the subunits. The three-dimensional evolutionary model of the eukaryotic conserved matrix arm has a striking similarity to the matrix arm quaternary structure in the bacterium Thermus thermophilus (rmsd=19 ?) and supports the previous finding that in eukaryotes the N-module is turned relative to the Q-module when compared to bacteria. By contrast, the evolutionary rates contained little information about the structure of the membrane arm. A large evolutionary model of 45 subunits and assembly factors allows to predict subunit positions and interactions (rmsd = 52.6 ?). The model supports an interaction of NDUFAF3, C8orf38 and C2orf56 during the assembly of the proximal matrix arm and the membrane arm. The model further suggests a tight relationship between the assembly factor NUBPL and NDUFA2, which both have been linked to iron-sulfur cluster assembly, as well as between NDUFA12 and its paralog, the assembly factor NDUFAF2.

Conclusions

The physical distance between subunits of complex I is a major correlate of the rate of protein evolution in the complex I matrix arm and is sufficient to infer parts of the complex??s structure with high accuracy. The resulting evolutionary model predicts the positions of a number of subunits and assembly factors.