bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct observation of Bin/amphiphysin/Rvs (BAR) domain-induced membrane curvature by means of molecular dynamics simulations
Authors: Blood Philip D. , Voth Gregory A.
Published: September 2006

The process of membrane curvature generation by BAR (Bin/amphiphysin/Rvs) domains is thought to involve the plastering of the negatively charged cell membrane to the positively charged concave surface of the BAR domain. Recent work [Peter, B. J.,
et al.
(2004)
Science
, 303,495–499; Masuda, M.,
et al.
(2006)
EMBO J.
25, 2889–2897; and Gallop, J. L.,
et al.
(2006)
EMBO J.
25, 2898–2910] has demonstrated the importance of the charged, crescent-shaped surface and the N-terminal amphipathic helices (present in N-BAR domains) for generating membrane curvature. These experiments suggest that curvature is generated by the synergistic action of the N-terminal helices embedding in the lipid bilayer and the charged crescent-shaped dimer acting to “scaffold” membrane curvature. Here, we present atomistic molecular dynamics simulations that directly show membrane binding to the concave face of N-BAR domains, resulting in the generation of local membrane curvature that matches the curvature presented by the BAR domain. These simulations provide direct molecular-scale evidence that BAR domains create curvature by acting as a scaffold, forcing the membrane to locally adopt the intrinsic shape of the BAR domain. We find that BAR domains bind strongly through the maximum curvature surface and, additionally, at an orientation that presents a lesser degree of curvature, thus enabling N-BAR domains to induce a range of local curvatures. Finally, we find that the N-terminal region may play a role in biasing the orientations of N-BAR domains on the membrane surface to those that favor binding to the concave face and subsequent membrane bending.
Defective RNA processing enhances RNA silencing and influences flowering ofArabidopsis
Authors: Herr Alan J. , Molnàr Attila , Jones Alex , Baulcombe David C.
Published: September 2006

Many eukaryotic cells use RNA-directed silencing mechanisms to protect against viruses and transposons and to suppress endogenous gene expression at the posttranscriptional level. RNA silencing also is implicated in epigenetic mechanisms affecting chromosome structure and transcriptional gene silencing. Here, we describe enhanced silencing phenotype (esp) mutants inArabidopsis thalianathat reveal how proteins associated with RNA processing and 3′ end formation can influence RNA silencing. These proteins were a putative DEAH RNA helicase homologue of the yeast PRP2 RNA splicing cofactor and homologues of mRNA 3′ end formation proteins CstF64, symplekin/PTA1, and CPSF100. The last two proteins physically associated with the flowering time regulator FY in the 3′ end formation complex AtCPSF. The phenotypes of the 3′ end formationespmutants include impaired termination of the transgene transcripts, early flowering, and enhanced silencing of theFCA-β mRNA. Based on these findings, we propose that the ESP-containing 3′ end formation complexes prevent transgene and endogenous mRNAs from entering RNA-silencing pathways. According to this proposal, in the absence of these ESP proteins, these RNAs have aberrant 3′ termini. The aberrant RNAs would enter the RNA silencing pathways because they are converted into dsRNA by RNA-dependent RNA polymerases.
Hereditary Neuropathy With Liability to Pressure Palsies Manifesting By Recurrent Neuropathic Pain
Authors: Barroso Fabio A , Leiguarda Ramón , Nogués Martín A.
Published: September 2006

Hereditary neuropathy with liability to pressure palsies is an autosomal dominant disease that presents with focal neurological deficits in the territory of peripheral nerves. The usual cause is a deletion of 1.5 Mb at chromosome 17p11.2.

It has been clear from several clinical series that other phenotypes, such as isolated sensory deficits, chronic mononeuropathies, motor sensory neuropathies like CMT1A, polyneuropathy like CIDP, and Davidenkow's syndrome, may also occur in affected families.

In this report, the authors present a new family with hereditary neuropathy with liability to pressure palsies (HNPP) in which one of the members suffered recurrent episodes of pain in the territory of peripheral nerve trunks along with generalized conduction nerve abnormalities and the common deletion of 1.5 Mb at 17p12.1.

On this basis, the authors propose that HNPP should be considered in the differential diagnosis of painful multiple mononeuropathy.
The feeding dynamics of broiler chickens
Authors: Collins L.M , Sumpter D.J.T
Published: September 2006

Contrary to a commonly held belief that broiler chickens need more space, there is increasing evidence that these birds are attracted to other birds. Indeed, commercially farmed birds exhibit a range of socially facilitated behaviours, such as increased feeding and preening in response to the presence of other birds. Social facilitation can generate feedback loops, whereby the adoption of a particular behaviour can spread rapidly and suddenly through the population. Here, by measuring the rate at which broiler chickens join and leave a feeding trough as a function of the number of birds already there, we quantify social facilitation. We use these measurements to parameterize a simulation model of chicken feeding behaviour. This model predicts, and further observations of broiler chickens confirm, that social facilitation leads to excitatory and synchronized patterns of group feeding. Such models could prove a powerful tool in understanding how feeding patterns depend on broiler house design.
The reinfection threshold regulates pathogen diversity: the case of influenza
Authors: Gökaydin Dinis , Oliveira-Martins José B , Gordo Isabel , Gomes M. Gabriela M
Published: September 2006

The awareness that pathogens can adapt and evolve over relatively short time-scales is changing our view of infectious disease epidemiology and control. Research on the transmission dynamics of antigenically diverse pathogens is progressing and there is increasing recognition for the need of new concepts and theories. Mathematical models have been developed considering the modelling unit in two extreme scales: either diversity is not explicitly represented or diversity is represented at the finest scale of single variants. Here, we use an intermediate approach and construct a model at the scale of clusters of variants. The model captures essential properties of more detailed systems and is much more amenable to mathematical treatment. Specificities of pathogen clusters and the overall potential for transmission determine the reinfection rates. These are, in turn, important regulators of cluster dynamics. Ultimately, we detect a reinfection threshold (RT) that separates different behaviours along the transmissibility axis: below RT, levels of infection are low and cluster substitutions are probable; while above RT, levels of infection are high and multiple cluster coexistence is the most probable outcome.
Are apes really inequity averse?
Authors: Bräuer Juliane , Call Josep , Tomasello Michael
Published: September 2006

Brosnan
et al
. (Brosnan, S. F., Schiff, H. C. & de Waal, F. B. M. 2005 Tolerance for inequity may increase with social closeness in chimpanzees.
Proc. R. Soc. B
272
, 253–258) found that chimpanzees showed increased levels of rejection for less-preferred food when competitors received better food than themselves and postulated as an explanation inequity aversion. In the present study, we extended these findings by adding important control conditions, and we investigated whether inequity aversion could also be found in the other great ape species and whether it would be influenced by subjects' relationship with the competitor. In the present study, subjects showed a pattern of food rejection opposite to the subjects of the above study by Brosnan
et al
. (2005). Our apes ignored
fewer
food pieces and stayed longer in front of the experimenter when a conspecific received better food than themselves. Moreover, chimpanzees begged more vigorously when the conspecific got favoured food. The most plausible explanation for these results is the food expectation hypothesis—seeing another individual receive high-quality food creates the expectation of receiving the same food oneself—and not inequity aversion.
How does resource supply affect evolutionary diversification?
Authors: Hall Alex R , Colegrave Nick
Published: September 2006

The availability of different resources in the environment can affect the outcomes of evolutionary diversification. A unimodal distribution of diversity with resource supply has been widely observed and explained previously in the context of selection acting in a spatially heterogeneous environment. Here, we propose an alternative mechanism to explain the relationship between resource supply and diversification that is based on selection for exploitation of different resources. To test this mechanism, we conducted a selection experiment using the bacteriumPseudomonas fluorescensin spatially homogeneous environments over a wide range of resource supply rates. Our results show that niche diversification peaks at intermediate levels of resource availability. We suggest that this unimodal relationship is due to evolutionary diversification that is driven by competition for resources but constrained by the ecological opportunity represented by different resource types. These processes may underlie some general patterns of diversity, including latitudinal gradients in species richness and the effects of anthropogenic enrichment of the environment.
Effects of molecular rotation in low-energy electron collisions of
Authors: Wolf Andreas , Kreckel H , Lammich L , Strasser D , Mikosch J , Glosík J , Plašil R , Altevogt S , Andrianarijaona V , Buhr H , Hoffmann J , Lestinsky M , Nevo I , Novotny S , Orlov D.A , Pedersen H.B , Terekhov A.S , Toker J , Wester R , Gerlich D , Schwalm D , Zajfman D
Published: September 2006

Measurements on the energetic structure of the dissociative recombination rate coefficient in the millielectronvolt range are described for

ions produced in the lowest rotational levels by collisional cooling and stored as a fast beam in the magnetic storage ring TSR (Test Storage Ring). The observed resonant structure is consistent with that found previously at the storage ring facility CRYRING in Stockholm, Sweden; theoretical predictions yield good agreement on the overall size of the rate coefficient, but do not reproduce the detailed structure. First studies on the nuclear spin symmetry influencing the lowest level populations show a small effect different from the theoretical predictions. Heating processes in the residual gas and by collisions with energetic electrons, as well as cooling owing to interaction with cold electrons, were observed in long-time storage experiments, using the low-energy dissociative recombination rate coefficient as a probe, and their consistency with the recent cold

measurements is discussed.
Isolates of ‘Candidatus Nostocoida limicola’ Blackall et al. 2000 should be described as three novel species of the genus Tetrasphaera, as Tetrasphaera jenkinsii sp. nov., Tetrasphaera vanveenii sp. nov. and Tetrasphaera veronensis sp. nov.
Authors: McKenzie C. M. , Seviour E. M. , Schumann P. , Maszenan A. M. , Liu J.-R. , Webb R. I. , Monis P. , Saint C. P. , Steiner U. , Seviour R. J.
Published: September 2006

Despite differences in their morphologies, comparative analyses of 16S rRNA gene sequences revealed high levels of similarity (>94 %) between strains of the filamentous bacterium ‘CandidatusNostocoida limicola’ and the cocciTetrasphaera australiensisandTetrasphaera japonicaand the rodTetrasphaera elongata, all isolated from activated sludge. These sequence data and their chemotaxonomic characters, including cell wall, menaquinone and lipid compositions and fingerprints of their 16S–23S rRNA intergenic regions, support the proposition that these isolates should be combined into a single genus containing six species, in the familyIntrasporangiaceaein theActinobacteria. This suggestion receives additional support from DNA–DNA hybridization data and when partial sequences of therpoC1gene are compared between these strains. Even though few phenotypic characterization data were obtained for these slowly growing isolates, it is proposed, on the basis of the extensive chemotaxonomic and molecular evidence presented here, that ‘CandidatusN. limicola’ strains Ben 17, Ben 18, Ben 67, Ben 68 and Ben 74 all be placed into the speciesTetrasphaera jenkinsiisp. nov. (type strain Ben 74T=DSM 17519T=NCIMB 14128T), ‘CandidatusN. limicola’ strain Ben 70 intoTetrasphaera vanveeniisp. nov. (type strain Ben 70T=DSM 17518T=NCIMB 14127T) and ‘CandidatusN. limicola’ strains Ver 1 and Ver 2 intoTetrasphaera veronensissp. nov. (type strain Ver 1T=DSM 17520T=NCIMB 14129T).
Gordonia defluvii sp. nov., an actinomycete isolated from activated sludge foam
Authors: Soddell Jacques A. , Stainsby Fiona M. , Eales Kathryn L. , Seviour Robert J. , Goodfellow Michael
Published: September 2006

Three strains of non-motile, Gram-positive, filamentous actinomycetes, isolates J4T, J5 and J59, initially recognized microscopically in activated sludge foam by their distinctive branching patterns, were isolated by micromanipulation. The taxonomic positions of the isolates were determined using a polyphasic approach. Almost-complete 16S rRNA gene sequences of the isolates were aligned with corresponding sequences of representatives of the suborder Corynebacterineae and phylogenetic trees were inferred using three tree-making algorithms. The organisms formed a distinct phyletic line in the Gordonia 16S rRNA gene tree. The three isolates showed 16S rRNA gene sequence similarities within the range 96.9–97.2 % with their nearest phylogenetic neighbours, namely Gordonia bronchialis DSM 43247T and Gordonia terrae DSM 43249T. Strain J4T was shown to have a chemotaxonomic profile typical of the genus Gordonia and was readily distinguished from representatives of the genus on the basis of Curie-point pyrolysis mass spectrometric data. The isolates shared nearly identical phenotypic profiles that distinguished them from representatives of the most closely related Gordonia species. It is evident from the genotypic and phenotypic data that the three isolates belong to a novel Gordonia species. The name proposed for this taxon is Gordonia defluvii sp. nov.; the type strain is J4T (=DSM 44981T=NCIMB 14149T).
Rickettsia asiatica sp. nov., isolated in Japan
Authors: Fujita Hiromi , Fournier Pierre-Edouard , Takada Nobuhiro , Saito Takehiro , Raoult Didier
Published: September 2006

The characterization of a novelRickettsiaspecies, first isolated fromIxodes ovatusticks in Japan in 1993, is described for which the nameRickettsia asiaticasp. nov. is proposed. Using multilocus sequence comparison, five rickettsial isolates fromI. ovatuscollected at various locations in Japan were found to be identical but belonged to a novel species. Serotyping also demonstrated this rickettsia to be distinct from previously describedRickettsiaspecies. The type strain ofRickettsia asiaticasp. nov. is IO-1T(=CSUR R2T). Following discussions held at the meeting of the International Committee on Systematics of Prokaryotes (ICSP) and its Judicial Commission (JC) in San Francisco, 2005, and in anticipation of the published minutes of the JC and ICSP, a committee consisting of the chairman of the ICSP, the chairman of the Judicial Commission of the ICSP and the Editor of the IJSEM has granted an exception in this case to the Rule governing the deposit of type material in two different collections in two different countries.
Actinoalloteichus hymeniacidonis sp. nov., an actinomycete isolated from the marine sponge Hymeniacidon perleve
Authors: Zhang Haitao , Zheng Wen , Huang Jianyu , Luo Hongli , Jin Yan , Zhang Wei , Liu Zhiheng , Huang Ying
Published: September 2006

A polyphasic study was undertaken to establish the taxonomic status of a Gram-positive, aerobic actinomycete, strain HPA177T, isolated from a marine sponge, Hymeniacidon perleve. The organism formed branching, non-fragmenting vegetative hyphae and produced black pigment. Chemotaxonomic characteristics were consistent with its assignment to the genus Actinoalloteichus. Analysis of the 16S rRNA gene sequence showed that strain HPA177T formed a robust clade with type strains of the genus Actinoalloteichus, but was distinct from them. A number of phenotypic characteristics also readily distinguished strain HPA177T from species of the genus Actinoalloteichus with validly published names. On the basis of the above data, it is proposed that strain HPA177T represents a novel species, Actinoalloteichus hymeniacidonis sp. nov. The type strain of Actinoalloteichus hymeniacidonis is HPA177T (=CGMCC 4.2500T=JCM 13436T).
Dermacoccus barathri sp. nov. and Dermacoccus profundi sp. nov., novel actinomycetes isolated from deep-sea mud of the Mariana Trench
Authors: Pathom-aree Wasu , Nogi Yuichi , Ward Alan C. , Horikoshi Koki , Bull Alan T. , Goodfellow Michael
Published: September 2006

The taxonomic positions of two actinobacterial strains isolated from Mariana Trench sediment were established using a combination of genotypic and phenotypic data. The strains, isolates MT2.1Tand MT2.2T, formed a distinct phyletic line in theMicrococcineae16S rRNA gene tree together withDermacoccus abyssiNCIMB 14084T. The isolates had chemical and phenotypic properties typical of members of the genusDermacoccusand could be distinguished sharply from one another and from the type strains ofDermacoccus abyssiandDermacoccus nishinomiyaensisusing DNA–DNA relatedness data. A range of phenotypic properties served to distinguish the two novel strains from one another and from the type strains of establishedDermacoccusspecies. The G+C contents of the DNAs of strains MT2.1Tand MT2.2Twere 66.8 and 69.1 mol%, respectively. It is evident that the two isolates merit recognition as novel species within the genusDermacoccus. The names proposed for these taxa areDermacoccus barathrisp. nov. (type strain MT2.1T=DSM 17574T=NCIMB 14081T) andDermacoccus profundisp. nov. (type strain MT2.2T=DSM 17575T=NCIMB 14084T).
Yonghaparkia alkaliphila gen. nov., sp. nov., a novel member of the family Microbacteriaceae isolated from an alkaline soil
Authors: Yoon Jung-Hoon , Kang So-Jung , Schumann Peter , Oh Tae-Kwang
Published: September 2006

Two Gram-positive, non-motile, non-spore-forming and rod-shaped actinomycete strains, KSL-113Tand KSL-133, were isolated from an alkaline soil in Korea, and their taxonomic positions were investigated by using a polyphasic approach. The strains grew optimally at 30 °C and pH 9.0. Phenotypic, phylogenetic and genetic similarities indicated that strains KSL-113Tand KSL-133 represent the same species. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains KSL-113Tand KSL-133 fell within the familyMicrobacteriaceaeof the suborderMicrococcineae, the highest 16S rRNA gene sequence similarity values (98.2 %) being obtained with respect toMicrocella putealisCV-2T. The 16S rRNA gene sequence similarities between strains KSL-113Tand KSL-133 and the other members of the familyMicrobacteriaceaeused in the phylogenetic analysis were less than 96.0 %. Strains KSL-113Tand KSL-133 could be clearly distinguished from members of the familyMicrobacteriaceaeon the basis of differences in chemotaxonomic properties, including the predominant menaquinone type, the cell-wall peptidoglycan type and the fatty acid profile. Accordingly, on the basis of the combined phenotypic, chemotaxonomic and phylogenetic data, strains KSL-113Tand KSL-133 constitute a novel genus and species of the familyMicrobacteriaceae, for which the nameYonghaparkia alkaliphilagen. nov., sp. nov. is proposed. The type strain ofYonghaparkia alkaliphilais KSL-113T(=KCTC 19126T=CIP 108920T).
Amycolatopsis australiensis sp. nov., an actinomycete isolated from arid soils
Authors: Tan Geok Yuan Annie , Robinson Stuart , Lacey Ernest , Goodfellow Michael
Published: September 2006

The taxonomic position of a group of mesophilic actinomycetes isolated from arid Australian soils was determined using a polyphasic approach. The organisms shared chemical and morphological markers typical of members of the genusAmycolatopsis. They had identical 16S rRNA gene sequences and formed a distinct phyletic line in theAmycolatopsis mediterraneiclade, being most closely related toA. mediterranei. In addition, they shared a range of phenotypic properties that distinguished them from representatives of all of the species classified in this clade. The combined genotypic and phenotypic data indicate that the strains merit species status within the genusAmycolatopsis. The name proposed for the novel species isAmycolatopsis australiensissp. nov.; the type strain is GY048T(=DSM 44671T=NCIMB 14142T).
Blastococcus jejuensis sp. nov., an actinomycete from beach sediment, and emended description of the genus Blastococcus Ahrens and Moll 1970
Authors: Lee Soon Dong
Published: September 2006

A novel actinomycete, strain KST3-10T, was isolated from sand sediment of a beach in Jeju, Korea, and was subjected to polyphasic taxonomic characterization. The organism produced circular, smooth, translucent, apricot-coloured colonies comprising coccoid- or rod-shaped cells. Phylogenetic analyses based on 16S rRNA gene sequences showed that the organism belonged to the family Geodermatophilaceae and consistently formed a distinct sub-branch outside the radiation of the genus Blastococcus. The organism showed 16S rRNA gene sequence similarity values of 98.2 % with respect to Blastococcus aggregatus DSM 4725T and 98.1 % with respect to Blastococcus saxobsidens BC444T. The type strains of the two Blastococcus species shared 98.2 % sequence similarity with respect to each other, whereas the levels of sequence similarity between the novel organism and the type strains of the less closely related neighbours, Modestobacter multiseptatus and Geodermatophilus obscurus, were in the range 96.2–96.9 %. The physiological, biochemical and chemotaxonomic data revealed that the novel organism can be readily differentiated from members of the genus Blastococcus and that it merits separate species status. On the basis of the phenotypic and genotypic evidence, strain KST3-10T represents a novel species of the genus Blastococcus, for which the name Blastococcus jejuensis sp. nov. is proposed. The type strain is KST3-10T (=NRRL B-24440T=KCCM 42251T).
Bowmanella denitrificans gen. nov., sp. nov., a denitrifying bacterium isolated from seawater from An-Ping Harbour, Taiwan
Authors: Jean Wen Dar , Chen Jwo-Sheng , Lin Yu-Te , Shieh Wung Yang
Published: September 2006

A heterotrophic, non-fermentative, denitrifying isolate, designated strain BD1T, was obtained from a seawater sample collected in the shallow coastal region of An-Ping Harbour, Tainan, Taiwan. The cells of strain BD1Twere Gram-negative. Cells grown in broth cultures were curved rods that were motile by means of a single polar flagellum. Growth occurred between 10 and 40 °C, with an optimum at 30–35 °C. Strain BD1Tgrew in NaCl levels of 0–10 %, with better growth occurring at 1–3 %. It grew aerobically and could achieve anaerobic growth by adopting a denitrifying metabolism with nitrate or nitrous oxide as the terminal electron acceptor. The major fatty acids were C16 : 0, C18 : 1ω7cand summed feature 3 (C16 : 1ω7cand/or C15 : 0iso 2-OH). The polar lipids consisted of phosphatidylethanolamine (56.6 %) and phosphatidylglycerol (43.4 %). The isoprenoid quinones were Q-8 (81.5 %), Q-9 (11.1 %) and Q-10 (7.4 %). The DNA G+C content was 50.0 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain BD1Tformed a distinct lineage in theGammaproteobacteriaand that it exhibited the highest level of sequence similarity with species of the generaAlteromonas(92.8–93.7 %),Aestuariibacter(93.0 %),Glaciecola(90.4–92.7 %) andSalinimonas(91.8 %). Strain BD1Twas distinguishable from species of these genera by the presence of Q-9 and Q-10. Phenotypically, strain BD1Twas also distinguishable from species of these genera in that it did not require NaCl for growth and was capable of denitrification. On the basis of the polyphasic data from this study, the isolate represents a novel species within a novel genus, for which the nameBowmanella denitrificansgen. nov., sp. nov. is proposed. The type strain ofBowmanella denitrificansis BD1T(=BCRC 17491T=JCM 13378T).
Plantibacter auratus sp. nov., in the family Microbacteriaceae
Authors: Lin Yi-Chueh , Yokota Akira
Published: September 2006

Strain NCIMB 9991Tis a Gram-positive, short rod-shaped, yellow-pigmented bacterium, with a high DNA G+C content, and was originally deposited in 1967 asArthrobactersp. The bacterium is aerobic, non-motile, catalase-positive and oxidase-negative. Comparative 16S rRNA gene sequencing studies demonstrated that this strain was highly related genealogically toPlantibacter flavusDSM 14012T. Strain IAM 14817T(=NCIMB 9991T) has the following characteristics: the predominant menaquinones are MK-9 and MK-10, the DNA G+C content is 68 mol%, the diamino acid in the cell wall is 2,4-l-diaminobutyric acid and the muramic acid in the peptidoglycan is of an acetyl type. The major fatty acid is 12-methyl tetradecanoic acid (anteiso-C15 : 0), followed by 14-methyl hexadecanoic acid (anteiso-C17 : 0), 14-methyl pentadecanoic acid (iso-C16 : 0) and hexadecanoic acid (C16 : 0). On the basis of morphological, physiological and chemotaxonomic characteristics, together with DNA–DNA hybridization and 16S rRNA gene sequence comparison, strain IAM 14817Trepresents a novel species within the genusPlantibacter, for which the namePlantibacter auratussp. nov. is proposed, with the type strain IAM 14817T(=NCIMB 9991T=NBRC 15702T).
Pediococcus ethanolidurans sp. nov., isolated from the walls of a distilled-spirit-fermenting cellar
Authors: Liu Limeng , Zhang Bin , Tong Huichun , Dong Xiuzhu
Published: September 2006

Two novelPediococcusstrains, Z-9Tand Z-17, were isolated from a distilled-spirit-fermenting cellar in Hebei Province, China. The cells were Gram-positive, non-spore-forming, non-motile cocci and occurred in pairs or tetrads. The strains were facultatively anaerobic and produced only lactic acid [d(−) andl(+) isomers in the ratio 50 : 50] from glucose fermentation. Catalase activity was not present. Both strains were able to grow in 6.5 % ethanol and at pH 3.5, but not in 4 % NaCl. The mean genomic G+C content of the two strains was 39.5±0.5 mol% (39 mol% for the type strain, Z-9T). The levels of 16S rRNA gene sequence similarity between the two novel strains and related species of the genusPediococcusranged from 98.3 to 98.7 %. The levels of DNA–DNA relatedness between strain Z-9Tand the phylogenetically closely related pediococciPediococcus damnosusLMG 11484T,Pediococcus inopinatusLMG 11409T,Pediococcus parvulusLMG 11486TandPediococcus cellicolaLMG 22956Twere 14.6, 33, 28.7 and 16.8 %, respectively. On the basis of phenotypic, genotypic and phylogenetic analyses, a novel species,Pediococcus ethanoliduranssp. nov., is proposed, with strain Z-9T(=AS 1.3889T=LMG 23354T) as the type strain.
Phylogenetic evaluation of cyanobacteria preserved as historic herbarium exsiccata
Authors: Palinska Katarzyna A. , Thomasius Christian F. , Marquardt Jürgen , Golubic Stjepko
Published: September 2006

Dried herbarium specimens of cyanobacteria (exsiccata) deposited over 100 years ago were analysed and characterized using combined morphological and molecular approaches. Six representative coccoid and filamentous cyanobacteria from two historic collections and a 15-year-old air-dried environmental sample were studied. Morphological features observed by light and electron microscopy were correlated with the results of 16S rRNA gene sequencing. Historic identifications achieved by means of classical morphology could thus be confirmed by extracted, amplified and sequenced 16S rRNA gene fragments. The results of this study open the possibility of providing genotypic characterizations to botanical type specimens, thus reconciling the botanical and bacteriological approaches to the taxonomic treatment of these micro-organisms.
Flavobacterium croceum sp. nov., isolated from activated sludge
Authors: Park Minjeong , Lu Shipeng , Ryu Seung Hyun , Chung Bok Sil , Park Woojun , Kim Chang-Jin , Jeon Che Ok
Published: September 2006

A Gram-negative, non-motile, rod-shaped bacterium, designated strain EMB47T, was isolated from activated sludge performing enhanced biological phosphorus removal in a sequencing batch reactor. Growth was observed between 10 and 40 °C (optimum, 25–35 °C) and between pH 5.0 and 8.5 (optimum, pH 7.5–8.0). The predominant fatty acids of strain EMB47T were iso-C16 : 0 3-OH, iso-C15 : 1 G, C15 : 0, iso-C15 : 0, iso-C14 : 0 and iso-C16 : 0 and it contained phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylcholine as polar lipids. The G+C content of the genomic DNA was 40.8 mol% and the major quinone was MK-6. Comparative 16S rRNA gene sequence analyses showed that strain EMB47T formed a distinct phyletic line within the genus Flavobacterium. The levels of 16S rRNA gene sequence similarity with respect to Flavobacterium species were below 94.7 %. On the basis of the phenotypic, chemotaxonomic and molecular data, strain EMB47T represents a novel species within the genus Flavobacterium, for which the name Flavobacterium croceum sp. nov. is proposed. The type strain is EMB47T (=KCTC 12611T=DSM 17960T).
Halobacterium jilantaiense sp. nov., a halophilic archaeon isolated from a saline lake in Inner Mongolia, China
Authors: Yang Yong , Cui Heng-Lin , Zhou Pei-Jin , Liu Shuang-Jiang
Published: September 2006

A novel halophilic archaeon, NG4T, was isolated from Jilantai salt lake in Inner Mongolia, China. The taxonomy of strain NG4T was studied by polyphasic methods. Strain NG4T grew at pH 5.5–8.5 and at a temperature of 22–55 °C. It was chemo-organotrophic, aerobic and required concentrations of 2.7–5.2 M NaCl and 0.05–0.3 M Mg2+ for growth. Cells were Gram-negative, slender rods. Colonies on agar plates containing 25 % (w/v) total salts were red, elevated and round. According to 16S rRNA gene sequence similarity, strain NG4T was phylogenetically related to Halobacterium salinarum DSM 3754T (98.2 %) and Halobacterium noricense A1T (97.3 %). The DNA G+C content was 64.2 mol%. DNA–DNA relatedness values with Hbt. salinarum DSM 3754T and Hbt. noricense A1T were 47 and 35 %, respectively. The polar lipids of strain NG4T consisted of phosphatidylglycerol, methylated phosphatidylglycerol phosphate, phosphatidylglycerol sulfate, triglycosyl diether, sulfated triglycosyl diether and sulfated tetraglycosyl diether. It was concluded that strain NG4T represents a novel species of the genus Halobacterium, for which the name Halobacterium jilantaiense sp. nov. is proposed. The type strain is NG4T (=CGMCC 1.5337T=JCM 13558T).
Linking growth to environmental histories in central Baltic young‐of‐the‐year sprat, Sprattus sprattus: an approach based on otolith microstructure analysis and hydrodynamic modelling
Authors: BAUMANN HANNES , HINRICHSEN HANS‐HARALD , VOSS RUDI , STEPPUTTIS DANIEL , GRYGIEL WLODZIMIERZ , CLAUSEN LOTTE W. , TEMMING AXEL
Published: September 2006

Otolith microstructure analysis and hydrodynamic modelling were combined to study growth patterns in young‐of‐the‐year (YoY) sprat, Sprattus sprattus, which were sampled in October 2002 in the central Baltic Sea. The observed ‘window of survival’, approximated by the distribution of back‐calculated days of first feeding (DFF), was narrow compared to the extended spawning season of sprat in the Baltic Sea (mean± SD = 22 June ± 14.1 days) and indicated that only individuals born in summer survived until October 2002. Within the group of survivors, individuals born later in the season exhibited faster larval, but more rapidly decreasing juvenile growth rates than earlier born conspecifics. Back‐calculated larval growth rates of survivors (0.48–0.69 mm day−1) were notably higher than those previously reported for average larval sprat populations, suggesting that the YoY population was predominantly comprised of individuals which grew faster during the larval stage. Daily mean temperatures, experienced across the entire YoY population, were derived from Lagrangian particle simulations and correlated with (1) detrended otolith growth and (2) back‐calculated, daily somatic growth rates of survivors. The results showed that abrupt changes in ambient temperature can be detected in the seasonal pattern of otolith growth, and that higher temperatures led to significantly faster growth throughout the entire age range of YoY sprat.
Geminin is essential for the development of preimplantation mouse embryos
Authors: Hara Kentaro , Nakayama Keiichi I. , Nakayama Keiko
Published: September 2006

Replication of DNA is strictly controlled to ensure that it occurs only once per cell cycle. Geminin has been thought to serve as a central mediator of this licensing mechanism by binding to and antagonizing the function of Cdt1 and thereby preventing re‐replication during S and G2 phases. We have now generated mice deficient in geminin to elucidate the physiologic role of this protein during development. Lack of geminin was shown to result in preimplantation mortality. A delay in the development of homozygous mutant embryos was first apparent at the transition from the four‐ to eight‐cell stages, concomitant with the disappearance of maternal geminin protein, and development was arrested at the eight‐cell stage. The mutant embryos manifest morphological abnormalities such as dispersed blastomeres with nuclei that are irregular both in size and shape as well as impaired cell–cell adhesion. DNA replication occurs but mitosis was not detected in the mutant embryos. The abnormal blastomeres contain damaged DNA and undergo apoptosis, likely as a consequence of the deregulation of DNA replication. Our results suggest that geminin is essential for cooperative progression of the cell cycle through S phase to M phase during the preimplantation stage of mouse development.
Rad54 is dispensable for the ALT pathway
Authors: Akiyama Koichi , Yusa Kosuke , Hashimoto Hideharu , Poonepalli Anuradha , Hande Manoor Prakash , Kakazu Naoki , Takeda Junji , Tachibana Makoto , Shinkai Yoichi
Published: September 2006

Some immortal cells use the alternative lengthening of telomeres (ALT) pathway to maintain their telomeres instead of telomerase. Previous studies revealed that homologous recombination (HR) contributes to the ALT pathway. To further elucidate molecular mechanisms, we inactivated Rad54 involved in HR, in mouse ALT embryonic stem (ES) cells. Although Rad54‐deficient ALT ES cells showed radiosensitivity in line with expectation, cell growth and telomeres were maintained for more than 200 cell divisions. Furthermore, although MMC‐stimulated sister chromatid exchange (SCE) was suppressed in the Rad54‐deficient ALT ES cells, ALT‐associated telomere SCE was not affected. This is the first genetic evidence that mouse Rad54 is dispensable for the ALT pathway.
Recovery of rat submandibular salivary gland function following removal of obstruction: a sialometrical and sialochemical study
Authors: Osailan Samira M. , Proctor Gordon B. , Carpenter Guy H. , Paterson Katherine L. , McGurk Mark
Published: September 2006

Functional recovery of the rat submandibular gland following ligation of the main excretory duct was examined. Rat submandibular glands were ligated for 1, 4 and 8 weeks using a micro‐clip with a plastic tube. Micro‐clips were removed and glands were allowed to recover for periods of 8, 16 and 24 weeks. Submandibular glands were stimulated with autonomimetic drugs (methacholine and isoprenaline) and salivas were collected from atrophic or de‐ligated and contralateral control glands. Glands recovered almost full size (92% of control gland) following 24 weeks of de‐ligation. Saliva volume secreted by ligated/de‐ligated (RSM) and control (LSM) glands were similar with different doses of agonists. Protein output expressed per gram of tissue wet weight was similar from both ligated/de‐ligated and control glands with all doses of agonist. Sodium and chloride levels were higher from de‐ligated glands than contralateral control glands. Protein electrophoresis showed similar profiles of salivary proteins in all samples with some minor differences. Acinar cells in de‐ligated glands showed a normal morphology, as indicated by light microscopy, whilst granular ductal cells were fewer and contained fewer secretory granules. Sodium potassium ATPase staining of striated ducts in de‐ligated glands was similar to that of control glands. It can be concluded that rat submandibular glands can regenerate following severe atrophy and secrete normal amounts of saliva containing broadly a full profile of secretory proteins. In contrast to acinar cells, ductal cells appear not to recover full function.
Dental health and oral mutans streptococci in 2–4‐year‐old Estonian children
Authors: OLAK JANA , MÄNDAR REET , KARJALAINEN SARA , SÖDERLING EVA , SAAG MARE
Published: September 2006

Objective.  The aim of this study was to assess the dental health and presence of mutans streptococci (MS) in 2–4‐year‐old Estonian children.

Methods.  The dental health of 472 2–4‐year‐old children was examined using a mirror and a penlight in 14 daycare centres representing seven communities around Estonia. The mean (± SD) age of the children was 41.4 ± 4.1 months (n = 222). Plaque samples of 222 children were employed to determine the presence of MS using the Dentocult® SM Strip mutans test.

Results.  Caries was diagnosed in 42% of the children, and the average (± SD) dmft index was 1.6 ± 2.5, ranging from 1.1 ± 1.2 in Tartu to 2.4 ± 3.1 in Võru. The proportion of caries‐free children decreased from 82% in the younger to 63% in the older group (P = 0.001). Among the tested subjects, 58% were colonized with MS, and those with caries were colonized more often than children with no visible caries (80% and 51%, respectively; P = 0.001).

Conclusions.  The prevalence of dental caries in Estonian 2–4‐year‐olds is higher than in the Nordic countries, but similar to other Baltic nations. Colonization by MS was associated with dental caries.
Multiple Synapse Formation: A Possible Compensatory Mechanism for Increased Cell Size in Rat Supraoptic Nucleus
Authors: Modney B. K. , Hatton G. I.
Published: September 2006

Magnocellular neuroendocrine cells of the rat supraoptic nucleus undergo numerous morphological changes during chronic dehydration of the animal. These changes include increases in cell size, the percentage of neuronal membrane in direct apposition and formation of new multiple synapses (i.e. terminals which form more than one synapse with adjacent somata and/or dendrites). Previous studies of multiple synapse formation in the supraoptic nucleus did not include adjustments for changes in somatic size, thus the full extent of synapse formation relative to increases in cell size was not known. That multiple synapse formation is a compensatory mechanism for increased somatic size was investigated by comparing animals that were either chronically dehydrated (by drinking 2% saline) or were well hydrated. Using morphometric techniques the percentage of somatic membrane contacted by single and multiple synapses was obtained. Estimates of somatic surface area were used together with stereologically derived estimates of the number of synapses per μm2 to calculate the number of single and multiple axo‐somatic synapses per neuron. Measures of soma‐somatic and soma‐dendritic membrane apposition and glial coverage were made to confirm earlier estimates of these parameters. Somatic surface area increased by more than 70% in dehydrated animals. Percentage of somatic membrane contacted by single synapses was lower (by 41%) and that contacted by multiple synapses was higher (by 100%) in dehydrated as compared to control animals. The number of single synapses was not different between the two groups but dehydrated animals had more multiple synapses per soma (23) than controls (6). With dehydration, there was an eight‐fold increase in the percentage of somatic membrane contacted by adjacent somatic/dendritic membrane. The surface area per somain such direct apposition was fifteen‐fold higher in dehydrates compared to controls. Glial processes covered the same proportion of somatic membrane in the two groups, while the actual area covered by glial processes per soma was higher in dehydrated animals. These results are consistent with the hypothesis that multiple synapse formation at least partially compensates for probable relative decreases in synaptic efficacy as synaptic density decreases when cells increase in size due to dehydration. This altered synaptic input as well as the increased direct apposition between adjacent neurons probably contribute to their enhanced activation during periods of increased hormone demand.
Effects of Bovine Follicular Fluid on Pulsatile Secretion of Gonadotrophin‐Releasing Hormone and Gonadotrophins in Ovariectomized Ewes
Authors: Li Jiang‐yuan , Francis Heather , Clarke Lain J.
Published: September 2006

Ovariectomized ewes were injected with charcoal‐extracted bovine follicular fluid (n = 5) or with hypophysectomized ewe serum (n = 5) after which hypophyseal portal blood samples were taken to monitor the release of gonadotrophin‐releasing hormone (GnRH). Peripheral blood samples were also taken to monitor plasma luteinizing hormone and follicle‐stimulating hormone (FSH) concentrations. Bovine follicular fluid treatment caused a 50% decrease in plasma FSH concentrations whereas hypophysectomized ewe serum did not significantly alter plasma FSH levels. The frequency and amplitude of luteinizing hormone and GnRH pulses was similar in both experimental groups. It is concluded that inhibin activity in bovine follicular fluid selectively suppresses the release of FSH by direct action on the pituitary gland, with no effect on GnRH secretion.
Dissociation of ACTH‐Secretory Mechanisms in Rat Pituitary Cells: Evidence that Basal and Vasopressin‐Stimulated Secretion Act via a Mechanism Distinct from that of Corticotrophin‐Releasing Factor
Authors: Schwartz J. , Familari M. , Wallace C. , Funder J. W.
Published: September 2006

To study the relationship between basal, corticotrophin‐releasing factor‐ (CRF) and vasopressin‐stimulated adrenocorticotrophic hormone (ACTH) secretion by rat anterior pituitary cells, dissociated anterior pituitary cells were seeded into tissue culture dishes and treated overnight with a cytotoxic conjugate specific for CRF‐target cells. Immediately after extensive washing, or 1, 3, 6, 9 or 12 days later, cellular ACTH content, basal secretion and secretion in response to CRF or vasopressin were measured. ACTH content and basal secretion rate increased over time in both cytotoxic conjugate‐pretreated and vehicle‐pretreated cell populations. Compared with vehicle‐pretreated cells, basal ACTH secretion was higher in cytotoxic conjugate‐pretreated populations by Day 3 and reached an apparent maximum by Day 6. In such cells, net ACTH secretion post‐vasopressin decreased as basal secretion increased; by Day 6 no vasopressin‐stimulated secretion was seen. In cytotoxic conjugate‐pretreated cells, the response to CRF was initially completely eliminated; however, as ACTH content and secretion increased with time, a small recovery of the response to CRF was observed on Days 3 and 6. In vehicle‐pretreated cells, ACTH secretion in response to vasopressin increased in parallel with basal secretion. The response to CRF increased progressively over Days 1 to 6 as well; this response was more closely related to the increases observed in ACTH content. The shift in responsiveness of the cytotoxic conjugate‐pretreated cells over time, from vasopressin‐responsive to CRF‐responsive, further demonstrates the dissociation of the mechanisms of the ACTH secretory responses to CRF and vasopressin. In addition, the increase in unstimulated secretion at the expense of the response to vasopressin in cytotoxic conjugate‐treated cells is consistent with a common pathway for vasopressin‐stimulated and basal release of ACTH.
An Ultrastructural Analysis of the Distribution of Angiotensin II in the Rat Brain
Authors: Oldfield Brian J. , Ganten Detlev , McKinley Michael J.
Published: September 2006

Immunopositive angiotensin II nerve fibres and terminals are widely distributed throughout the rat brain, including areas of the brain with and without a blood‐brain barrier. Ultrastructural examination indicates that in the circumventricular organs (areas which lack a blood‐brain barrier), many angiotensin ll‐positive nerve terminals are closely aligned with fenestrated blood vessels and do not have synaptic specializations. This appearance is in contrast to that of angiotensin II terminals in regions with a blood‐brain barrier where there exists a more typical synaptic configuration. In both cases, angiotensin II is contained within large (100 to 125 nm) vesicles which coexist with smaller, lucent, non‐immunoreactive vesicles. These observations suggest a possible duality of function such that angiotensin II in circumventricular organs may be secreted into the circulation, whereas angiotensin II in the remainder of the brain is more likely to be acting as a neurotransmitter or neuromodulator.
The Cholesterol Side‐Chain Cleavage Complex in Human Brain White Matter
Authors: Le Goascogne C. , Gouézou M. , Robel P. , Defaye G. , Chambaz E. , Waterman M. R. , Baulieu E. E.
Published: September 2006

Specific antibodies obtained in rabbits after injection of bovine cholesterol side‐chain cleavage enzymes cytochrome P‐450scc, adrenodoxin and adrenodoxin‐reductase were used for immunohistochemical studies in human brain. The three enzymes were co‐localized in the white matter of the cerebellum. This observation strongly suggests the existence of steroidogenic activity in human oligodendrocytes, as previously reported in the rat, and suggests that the concept of ‘neurosteroids’ can be applied to Δ5–3ß‐hydroxysteroid metabolites of cholesterol that accumulate in human brain.
Neuroendocrine Regulation of Canine Gastric Secretion, Emptying and Blood Flow
Authors: Lenz H. Jürgen
Published: September 2006

Several peptides have been implicated as central nervous system transmitters regulating various peripheral organ systems. This study examined the central nervous system effects of rat corticotrophin‐releasing factor (CRF), salmon calcitonin (CT), β‐endorphin (β‐End), neurotensin (NT), rat calcitonin gene‐related peptide (CGRP) and bombesin (BOM) on gastric acid secretion, gastric emptying and left gastric artery flow in conscious dogs. All of these peptides, injected into the third cerebral ventricle, significantly inhibited gastric acid secretion but not plasma gastrin concentrations stimulated by a liquid protein meal. Ganglionic blockade with chlorisondamine abolished the gastric inhibitory action of CRF, CT, β‐End and NT but not of CGRP and BOM. Truncal, subdiaphragmatic vagotomy prevented the gastric inhibitory actions of β‐End and NT only, while bilateral adrenalectomy did not affect gastric acid inhibition induced by any of the six peptides. Cerebroventricular administration of CRF, NT and BOM significantly delayed gastric emptying of the protein meal while β‐End, CT and CGRP were not effective. Only BOM significantly increased left gastric artery flow. These results indicate that various neuropeptides alter gastric functions in a differentiated fashion and via distinct pathways. CRF and CT inhibit meal‐stimulated gastric acid secretion by activation of sympathetic efferents. β‐End and NT inhibit meal‐stimulated acid secretion by inhibition of vagal efferents while the pathways that mediate CT‐ and CGRP‐induced gastric acid inhibition in the dog are unknown. Gastrin, the adrenal glands and changes in gastric emptying or blood flow do not play a role in mediating gastric acid inhibition produced by Cerebroventricular administration of CRF, CT, β‐End, NT, CGRP and BOM.