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1.
Data Brief ; 35: 106930, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33748366

RESUMO

We describe here a multiproxy dataset (grain size, environmental magnetism, stable carbon isotope, total nitrogen, and total organic carbon) generated on a ~116 cm long trench profile from the high altitude alpine Badnikund lake in the Central Himalaya. The dataset also includes environmental magnetic and organic geochemistry data on catchment soils of the Bednikund lake. The presented data is related to the research article "Middle Holocene Indian summer monsoon variability and its impact on cultural changes in the Indian subcontinent" [1]. The chronology of the Bednikund lake trench (BBK) profile is well established with seven AMS 14C dates. The multiproxy data is provided in tabular format in an excel file along with ages in Mendeley Data Repository. The multiproxy data can be significantly utilized for regional correlation of Indian summer monsoon (ISM) variability during the middle Holocene as well as for correlation of global climatic events. The data can also be reutilized in paleoclimate modelling for precipitation change over the past ~6000 years.

2.
Stand Genomic Sci ; 9(3): 449-61, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25197431

RESUMO

Granulicella tundricola strain MP5ACTX9(T) is a novel species of the genus Granulicella in subdivision 1 Acidobacteria. G. tundricola is a predominant member of soil bacterial communities, active at low temperatures and nutrient limiting conditions in Arctic alpine tundra. The organism is a cold-adapted acidophile and a versatile heterotroph that hydrolyzes a suite of sugars and complex polysaccharides. Genome analysis revealed metabolic versatility with genes involved in metabolism and transport of carbohydrates, including gene modules encoding for the carbohydrate-active enzyme (CAZy) families for the breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides such as plant based carbon polymers. The genome of G. tundricola strain MP5ACTX9(T) consists of 4,309,151 bp of a circular chromosome and five mega plasmids with a total genome content of 5,503,984 bp. The genome comprises 4,705 protein-coding genes and 52 RNA genes.

3.
Stand Genomic Sci ; 9(1): 71-82, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24501646

RESUMO

Granulicella mallensis MP5ACTX8(T) is a novel species of the genus Granulicella in subdivision 1of Acidobacteria. G. mallensis is of ecological interest being a member of the dominant soil bacterial community active at low temperatures and nutrient limiting conditions in Arctic alpine tundra. G. mallensis is a cold-adapted acidophile and a versatile heterotroph that hydrolyzes a suite of sugars and complex polysaccharides. Genome analysis revealed metabolic versatility with genes involved in metabolism and transport of carbohydrates. These include gene modules encoding the carbohydrate-active enzyme (CAZyme) family involved in breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides including plant based carbon polymers. The genome of Granulicella mallensis MP5ACTX8(T) consists of a single replicon of 6,237,577 base pairs (bp) with 4,907 protein-coding genes and 53 RNA genes.

4.
FEMS Microbiol Ecol ; 82(2): 341-55, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22486608

RESUMO

Acidobacteria are among the most abundant bacterial phyla found in terrestrial ecosystems, but relatively little is known about their diversity, distribution and most critically, their function. Understanding the functional activities encoded in their genomes will provide insights into their ecological roles. Here we describe the genomes of three novel cold-adapted strains of subdivision 1 Acidobacteria. The genomes consist of a circular chromosome of 6.2 Mbp for Granulicella mallensis MP5ACTX8, 4.3 Mbp for Granulicella tundricola MP5ACTX9, and 5.0 Mbp for Terriglobus saanensis SP1PR4. In addition, G. tundricola has five mega plasmids for a total genome size of 5.5 Mbp. The three genomes showed an abundance of genes assigned to metabolism and transport of carbohydrates. In comparison to three mesophilic Acidobacteria, namely Acidobacterium capsulatum ATCC 51196, 'Candidatus Koribacter versatilis' Ellin345, and 'Candidatus Solibacter usitatus' Ellin6076, the genomes of the three tundra soil strains contained an abundance of conserved genes/gene clusters encoding for modules of the carbohydrate-active enzyme (CAZyme) family. Furthermore, a large number of glycoside hydrolases and glycosyl transferases were prevalent. We infer that gene content and biochemical mechanisms encoded in the genomes of three Arctic tundra soil Acidobacteria strains are shaped to allow for breakdown, utilization, and biosynthesis of diverse structural and storage polysaccharides and resilience to fluctuating temperatures and nutrient-deficient conditions in Arctic tundra soils.


Assuntos
Acidobacteria/metabolismo , Carbono/metabolismo , Genoma Bacteriano , Microbiologia do Solo , Solo/química , Acidobacteria/genética , Acidobacteria/fisiologia , Regiões Árticas , Metabolismo dos Carboidratos , Hibridização Genômica Comparativa , DNA Bacteriano/genética , Ecossistema , Tamanho do Genoma , Filogenia , Plasmídeos/genética , Polissacarídeos Bacterianos/metabolismo , RNA Ribossômico 16S/genética
5.
Stand Genomic Sci ; 7(1): 59-69, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-23450133

RESUMO

Terriglobus saanensis SP1PR4(T) is a novel species of the genus Terriglobus. T. saanensis is of ecological interest because it is a representative of the phylum Acidobacteria, which are dominant members of bacterial soil microbiota in Arctic ecosystems. T. saanensis is a cold-adapted acidophile and a versatile heterotroph utilizing a suite of simple sugars and complex polysaccharides. The genome contained an abundance of genes assigned to metabolism and transport of carbohydrates including gene modules encoding for carbohydrate-active enzyme (CAZyme) family involved in breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides. T. saanensis SP1PR4(T) represents the first member of genus Terriglobus with a completed genome sequence, consisting of a single replicon of 5,095,226 base pairs (bp), 54 RNA genes and 4,279 protein-coding genes. We infer that the physiology and metabolic potential of T. saanensis is adapted to allow for resilience to the nutrient-deficient conditions and fluctuating temperatures of Arctic tundra soils.

6.
Int J Syst Evol Microbiol ; 62(Pt 9): 2097-2106, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22058325

RESUMO

Four aerobic bacteria, designated MP5ACTX2(T), MP5ACTX8(T), MP5ACTX9(T) and S6CTX5A(T), were isolated from tundra soil of north-western Finland (69° 03' N 20° 50' E). Cells of all isolates were Gram-negative, non-motile rods. Phylogenetic analysis indicated that they belonged to the genus Granulicella of subdivision 1 of the phylum Acidobacteriahttp://dx.doi.org/10.1601/nm.7918. 16S rRNA gene sequence similarity between the new isolates and the type strains of Granulicella aggregans, Granulicella paludicola, Granulicella pectinivorans and Granulicella rosea ranged from 94 to 99 %. Analysis of the RNA polymerase beta subunit (rpoB) gene sequence indicated that the isolates represented novel species of the genus Granulicella (<92 % rpoB sequence similarity between the isolates and members of the genus Granulicella). This was also confirmed by low DNA-DNA relatedness (31 %) between strain S6CTX5A(T) and the type strain of G. pectinivorans, which exhibited 99.1 % 16S rRNA gene sequence similarity and 91.7 % rpoB gene sequence similarity. The isolates grew at pH 3.5-6.5 and at 4-26 °C. Sugars were the preferred growth substrates. The major cellular fatty acids were iso-C(15 : 0), C(16 : 1)ω7c and C(16 : 0) and the major isoprenoid quinone was MK-8. The DNA G+C content was 56-60 mol%. On the basis of phylogenetic analysis and chemotaxonomic and physiological data, the isolates represent four novel species of the genus Granulicella, for which the names Granulicella arctica MP5ACTX2(T) (= ATCC BAA-1858(T) = DSM 23128(T)), Granulicella mallensis MP5ACTX8(T) (= ATCC BAA-1857(T) = DSM 23137(T)), Granulicella tundricola MP5ACTX9(T) (ATCC BAA-1859(T) = DSM 23138(T)) and Granulicella sapmiensis S6CTX5A(T) (= LMG 26174(T) = DSM 23136(T)) are proposed. An emended description of the genus Granulicella is also presented.


Assuntos
Acidobacteria/classificação , Filogenia , Microbiologia do Solo , Acidobacteria/genética , Acidobacteria/isolamento & purificação , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Ácidos Graxos/análise , Finlândia , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo
7.
Int J Syst Evol Microbiol ; 61(Pt 8): 1823-1828, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21186292

RESUMO

Two aerobic bacterial strains, designated SP1PR4(T) and SP1PR5, were isolated from tundra soil samples collected from Saana fjeld, North-western Finland (69° 03' N 20° 50' E). Cells of both strains were Gram-negative, non-motile rods. Phylogenetic analysis indicated that the strains belong to the genus Terriglobus in subdivision 1 of the phylum Acidobacteria. Strains SP1PR4(T) and SP1PR5 shared identical BOX and ERIC fingerprints and 99.7 % 16S rRNA gene similarity indicating that, together with their identical physiological features, these strains are members of the same species. The 16S rRNA gene sequence similarity of SP1PR4(T) and SP1PR5 with Terriglobus roseus DSM 18391(T) was 97.1 %. A low DNA-DNA hybridization value (<20 %) and rpoB gene sequence similarity (83.6 %) with T. roseus DSM 18391(T) indicated that the tundra soil isolates represent novel members of the genus Terriglobus. Strains SP1PR4(T) and SP1PR5 grew at pH 4.5-7.5 and 4-30 °C. Sugars were the preferred growth substrates. The major cellular fatty acids were iso-C(15 : 0), C(16 : 1)ω7c, iso-C(13 : 0) and C(16 : 0). The DNA G+C content of strain SP1PR4(T) was 57.3 mol%. Based on phylogenetic, chemotaxonomic and physiological analyses, the name Terriglobus saanensis sp. nov. is proposed to accommodate the two strains; the type strain is SP1PR4(T) ( = DSM 23119(T)  = ATCC BAA-1853(T)).


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Microbiologia do Solo , Bactérias/genética , Bactérias/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
8.
Plant Mol Biol ; 51(1): 119-33, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12602896

RESUMO

Picea abies (L.) Karst. (Norway spruce) employs constitutive and induced resin terpenoids as major chemical and physical defense-shields against insects and pathogens. In recent work, we showed that a suite of terpenoids, monoterpenoids and diterpenoids was induced in stems of Norway spruce after treatment of trees with methyl jasmonate (MeJA) (Martin et al., 2002). Increase of enzyme activities of terpenoid biosynthesis and accumulation of terpenoids was associated with MeJA-induced de novo differentiation of xylem resin ducts. The formation of defense-related traumatic resin ducts was also found in Norway spruce after attack by stem boring insects or after infestation with fungal pathogens. In the present study, we analyzed the traumatic resin response in Norway spruce further at the molecular genetic level. Treatment of trees with MeJA induced transient transcript accumulation of monoterpenoid synthases and diterpenoid synthases in stem tissues of Norway spruce. In screening for defense-related terpenoid synthase (TPS) genes from Norway spruce, a full-length monoterpenoid synthase cDNA, PaJF67, was isolated and the recombinant enzyme expressed in E. coli and functionally characterized in vitro. The cloned PaJF67 cDNA represents a new monoterpenoid synthase gene and the gene product was identified as 3-carene synthase. The enzyme encoded by PaJF67 forms stereospecifically (+)-3-carene (78% of total product) together with minor acyclic and cyclic monoterpenes, including the mechanistically closely related terpinolene (11% of total product). (+)-3-Carene is a characteristic monoterpene of constitutive and induced oleoresin defense of Norway spruce and other members of the Pinaceae.


Assuntos
Acetatos/farmacologia , Alquil e Aril Transferases/genética , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/fisiologia , Picea/enzimologia , Reguladores de Crescimento de Plantas/farmacologia , Alquil e Aril Transferases/química , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA , Escherichia coli/enzimologia , Escherichia coli/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Oxilipinas , Filogenia , Picea/efeitos dos fármacos , Picea/genética , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
9.
Plant Physiol ; 130(3): 1263-75, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12427993

RESUMO

NH(4)(+) acquisition by plant roots is thought to involve members of the NH(4)(+) transporter family (AMT) found in plants, yeast, bacteria, and mammals. In Arabidopsis, there are six AMT genes of which AtAMT1;1 demonstrates the highest affinity for NH(4)(+). Ammonium influx into roots and AtAMT1;1 mRNA expression levels are highly correlated diurnally and when plant nitrogen (N) status is varied. To further investigate the involvement of AtAMT1;1 in high-affinity NH(4)(+) influx, we identified a homozygous T-DNA mutant with disrupted AtAMT1;1 activity. Contrary to expectation, high-affinity (13)NH(4)(+) influx in the amt1;1:T-DNA mutant was similar to the wild type when grown with adequate N. Removal of N to increase AtAMT1;1 expression decreased high-affinity (13)NH(4)(+) influx in the mutant by 30% compared with wild-type plants, whereas low-affinity (13)NH(4)(+) influx (250 microM-10 mM NH(4)(+)) exceeded that of wild-type plants. In these N-deprived plants, mRNA copy numbers of root AtAMT1;3 and AtAMT2;1 mRNA were significantly more increased in the mutant than in wild-type plants. Under most growth conditions, amt1;1:T-DNA plants were indistinguishable from the wild type, however, leaf morphology was altered. However, when grown with NH(4)(+) and sucrose, the mutant grew poorly and died. Our results are the first in planta evidence that AtAMT1;1 is a root NH(4)(+) transporter and that redundancies within the AMT family may allow compensation for the loss of AtAMT1;1.


Assuntos
Arabidopsis/genética , Proteínas de Transporte/genética , Proteínas de Transporte de Cátions , Proteínas de Plantas/genética , Sulfato de Amônio/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Transporte Biológico/fisiologia , Proteínas de Transporte/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Perfilação da Expressão Gênica , Mutação , Nitratos/farmacologia , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Compostos de Potássio/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
J Exp Bot ; 53(370): 855-64, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11912228

RESUMO

Inorganic nitrogen concentrations in soil solutions vary across several orders of magnitude among different soils and as a result of seasonal changes. In order to respond to this heterogeneity, plants have evolved mechanisms to regulate and influx. In addition, efflux analysis using (13)N has revealed that there is a co-ordinated regulation of all component fluxes within the root, including biochemical fluxes. Physiological studies have demonstrated the presence of two high-affinity transporter systems (HATS) for and one HATS for in roots of higher plants. By contrast, in Arabidopsis thaliana there exist seven members of the NRT2 family encoding putative HATS for and five members of the AMT1 family encoding putative HATS for. The induction of high-affinity transport and Nrt2.1 and Nrt2.2 expression occur in response to the provision of, while down-regulation of these genes appear to be due to the effects of glutamine. High-affinity transport and AMT1.1 expression also appear to be subject to down-regulation by glutamine. In addition, there is evidence that accumulated and may act post-transcriptionally on transporter function. The present challenge is to resolve the functions of all of these genes. In Aspergillus nidulans and Chlamydomonas reinhardtii there are but two high-affinity transporters and these appear to have undergone kinetic differentiation that permits a greater efficiency of absorption over the wide range of concentration normally found in nature. Such kinetic differentiation may also have occurred among higher plant transporters. The characterization of transporter function in higher plants is currently being inferred from patterns of gene expression in roots and shoots, as well as through studies of heterologous expression systems and knockout mutants.


Assuntos
Proteínas de Arabidopsis , Proteínas de Transporte de Cátions , Nitratos/metabolismo , Proteínas de Plantas , Plantas/metabolismo , Compostos de Amônio Quaternário/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Regulação para Baixo/genética , Regulação da Expressão Gênica de Plantas , Modelos Biológicos , Transportadores de Nitrato , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas/genética , Solo/análise
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