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1

REGULAR PAPER Codominance of Acer saccharum and Fagus grandifolia  

E-print Network

with Acer saccharum in southern Quebec, Canada. In an old-growth forest, the degree of dominance by the two to the main- tenance of Acer­Fagus codominance at the scale of local landscapes. Keywords American beech Á

Lechowicz, Martin J.

2

Formation of cis-coniferin in cell-free extracts of Fagus grandifolia Ehrh bark  

NASA Technical Reports Server (NTRS)

American beech (Fagus grandifolia Ehrh) bark exclusively accumulates cis-monolignols and their glucosidic conjugates; no evidence for the accumulation of trans-monolignols has been found. The glucosyltransferase from this source exhibits a very unusual substrate specificity for cis, and not trans, monolignols. This is further evidence that cis monolignols are involved in lignin formation in these plant tissues. Preliminary evidence for the existence of a novel trans-cis monolignol isomerase was obtained, in agreement with our contention that this isomerization is not photochemically mediated.

Yamamoto, E.; Inciong, E. J.; Davin, L. B.; Lewis, N. G.

1990-01-01

3

Exclusive accumulation of Z-isomers of monolignols and their glucosides in bark of Fagus grandifolia  

NASA Technical Reports Server (NTRS)

In addition to Z-coniferyl and Z-sinapyl alcohols, bark extracts of Fagus grandifolia also contain significant amounts of the glucosides, Z-coniferin, Z-isoconiferin (previously called faguside) and Z-syringin. The corresponding E-isomers of these glucosides do not accumulate to a detectable level. The accumulation of the Z-isomers suggests that either they are not lignin precursors or that they are reservoirs of monolignols for subsequent lignin biosynthesis; it is not possible to distinguish between these alternatives. The co-occurrence of Z-coniferin and Z-isoconiferin demonstrate that glucosylation of monolignols can occur at either the phenolic or the allylic hydroxyl groups.

Lewis, N. G.; Inciong, E. J.; Ohashi, H.; Towers, G. H.; Yamamoto, E.

1988-01-01

4

Codominance of Acer saccharum and Fagus grandifolia: the role of Fagus root sprouts along a slope gradient in an old-growth forest.  

PubMed

We studied how the unusual capacity of mature Fagus grandifolia to form clumps of clonal stems from root sprouts can contribute to its frequent codominance with Acer saccharum in southern Quebec, Canada. In an old-growth forest, the degree of dominance by the two species shifted along topographic gradients spanning a few hundreds of meters, with Fagus more frequent on lower slopes and Acer on upper slopes. The frequency distribution of Fagus stem diameter had an inverse J distribution at all slope positions, which is indicative of continuous recruitment. Acer stem diameter also had an inverse J pattern, except at lower slope positions where size structure was discontinuous. For stems <2 m tall, Fagus regenerated mainly by sprouts at the upper and mid-slopes, while regeneration from seed was more pronounced on the lower slope. This change of regeneration mode affected the spatial pattern of Fagus stems. Understory trees of Fagus were positively correlated with conspecific canopy trees on upper and mid-slopes, but not on lower slopes where Fagus regenerated mainly by seedlings. Understory trees of Acer were positively correlated with conspecific canopy trees only on the mid-slope. There were many Fagus seedlings around Acer canopy trees at the lower slope, suggesting the potential replacement of Acer canopy trees by Fagus. This study suggests that the regeneration traits of the two species changed with slope position and that Fagus patches originating from root sprouts can contribute to the maintenance of Acer-Fagus codominance at the scale of local landscapes. PMID:20182904

Takahashi, Koichi; Arii, Ken; Lechowicz, Martin J

2010-09-01

5

Habitat differences influence genetic impacts of human land use on the American beech (Fagus grandifolia).  

PubMed

Natural reforestation after regional forest clearance is a globally common land-use sequence. The genetic recovery of tree populations in these recolonized forests may depend on the biogeographic setting of the landscape, for instance whether they are in the core or in the marginal part of the species' range. Using data from 501 individuals genotyped across 7 microsatellites, we investigated whether regional differences in habitat quality affected the recovery of genetic variation in a wind-pollinated tree species, American beech (Fagus grandifolia) in Massachusetts. We compared populations in forests that were recolonized following agricultural abandonment to those in remnant forests that have only been logged in both central inland and marginal coastal regions. Across all populations in our entire study region, recolonized forests showed limited reduction of genetic diversity as only observed heterozygosity was significantly reduced in these forests (H(O) = 0.520 and 0.590, respectively). Within inland region, this pattern was observed, whereas in the coast, recolonized populations exhibited no reduction in all genetic diversity estimates. However, genetic differentiation among recolonized populations in marginal coastal habitat increased (F(st) logged = 0.072; F(st) secondary = 0.249), with populations showing strong genetic structure, in contrast to inland region. These results indicate that the magnitude of recovery of genetic variation in recolonized populations can vary at different habitats. PMID:25138571

Lumibao, Candice Y; McLachlan, Jason S

2014-01-01

6

Dispersal versus climate: Expansion of Fagus and Tsuga into the Upper Great Lakes region  

Microsoft Academic Search

Pollen records for American beech (Fagus grandifolia) and eastern hemlock (Tsuga canadensis) compiled from 50 sites in Michigan and Wisconsin, USA, show that both species entered the Upper Great Lakes region about 7000 yr B.P., reaching their western and southwestern boundaries between 2000 and 1000 yr B.P. Fagus advanced northward into lower Michigan as a continuous front, except where Lake

M. B. Davis; K. D. Woods; S. L. Webb; R. P. Futyma

1986-01-01

7

Fagus dominance in Chinese montane forests: natural regeneration of Fagus lucida and Fagus hayatae var. pashanica  

Microsoft Academic Search

Fagus species are important components of certain mesic temperate forests in the Northern Hemisphere. Of eleven Fagus species distinguished, five are found in China. Chinese beeches are restricted to the mountains of southern China. In the montane zones of the northern subtropics beeches (Fagus engleriana in the north, and Fagus hayatae var. pashanica in the northwest) often predominate in the

K. F. Cao

1995-01-01

8

Growth strategies of main trees and forest architecture of a Fagus-Magnolia forest in Florida, USA  

Microsoft Academic Search

Growth strategies of six species of trees are compared and used to analyze forest architecture. They included the overstory speciesFagus grandifolia, Magnolia grandiflora, Pinus glabra andLiquidambar styraciflua, and the understory speciesOstrya virginiana andIlex opaca. The six species were abundant in Woodyard Hammock, an old-growth forest in northern Florida, USA. Height, stem diameter, crown projection and radial growth were measured in

Rob Peters; William J. Platt

1996-01-01

9

Araucaria grandifolia Feruglio from the Lower Cretaceous of Patagonia, Argentina  

Microsoft Academic Search

Araucaria grandifolia Feruglio is emended based on new material, with cuticle preserved, found at the type locality within the Punta del Barco Formation, Lower Cretaceous of Santa Cruz Province. The morphology of the leaves, secondary xylem of the branches and cuticular analysis as seen under light and scanning and transmission electron microscopes allowed comparison of this taxon to living and

Georgina M. Del Fueyo; Ana Archangelsky

2002-01-01

10

Do Interspecific Differences in Sapling Growth Traits Contribute to the Co-dominance of Acer saccharum and Fagus grandifolia?  

E-print Network

species in an old-growth forest in southern Quebec, Canada was examined. Two predictions were evaluated forested landscapes. Key words: American beech, crown architecture, crown allometry, height growth rate

Lechowicz, Martin J.

11

Triterpenes as ?-glucosidase inhibitors from Fagus hayatae.  

PubMed

Triterpenoids, 1-3, 8 and 9, along with 24 known compounds were isolated from leaves and twigs of Fagus hayatae. Of these, compound 1, 1,10-seco-3?,10?,23-trihydroxyolean-12-ene-1,28-dioic acid 1,23-lactone, possesses a hitherto unknown 1,10-seco-oleanane skeleton. In addition, 2,3-seco-20(29)-lupene-2,3-dioic acid (16), previously described as a synthetic product, is now established as a plant natural product; the neolignan-9'-O-rhamnoside 19 is also characterized herein. Their structures were deduced mainly by 1D and 2D NMR spectroscopic analyses. Seven of these compounds possess moderate inhibitory activity against ?-glucosidase type IV (Bacillus stearothermophilus). PMID:22169017

Lai, Yi-Chun; Chen, Chien-Kuang; Tsai, Sheng-Fa; Lee, Shoei-Sheng

2012-02-01

12

Original article Mineral nutrients of beech (Fagus sylvatica) bark  

E-print Network

in southern Swedish beech forests has led to increased forest soil acidification [30]. The amountOriginal article Mineral nutrients of beech (Fagus sylvatica) bark in relation to frost sensitivity and soil treatments in southern Sweden Anna Maria Jönsson* Dept. of Ecology, Forest Ecology, Lund

Boyer, Edmond

13

Climatic limits for the present distribution of beech (Fagus L.) species in the world  

E-print Network

elevational limits for beech species in each region. Methods In total, 292 lower/southern limit and 310 upperORIGINAL ARTICLE Climatic limits for the present distribution of beech (Fagus L.) species, Beijing 100871, China. E-mail: jyfang@urban.pku.edu.cn ABSTRACT Aim Beech (Fagus L., Fagaceae) species

Lechowicz, Martin J.

14

Wieferich, D, D. B. Hayes, D. McCullough, and N. Schwalm. In press. Distribution of American Beech (Fagus grandifolia) and Beech Scale (Cryptococcus fagisuga Lind.) in Michigan from 2005 to 2009.  

E-print Network

of the Stronach Dam Removal on Fish in the Pine River, Manistee County, Michigan. Transactions of the American. Northern Journal of Applied Forestry Hansen, J. and D. B. Hayes. In press. Long-Term Implications of Dam Removal for Macroinvertebrate Communities In Michigan and Wisconsin Rivers, United States. River Research

15

Comparison of extracellular enzymes of Fusobacterium necrophorum subsp. necrophorum and Fusobacterium necrophorum subsp. funduliforme.  

PubMed Central

A total of 10 strains each of Fusobacterium necrophorum subsp. necrophorum and Fusobacterium necrophorum subsp. funduliforme were tested for the production of 13 extracellular enzymes. DNase, alkaline phosphatase, and lipase were predominantly associated with all the strains of F. necrophorum subsp. necrophorum, with DNase not detected in any of the strains of F. necrophorum subsp. funduliforme. In addition, the strains of F. necrophorum subsp. necrophorum were generally more hemolytic than those of F. necrophorum subsp. funduliforme. Lecithinase, beta-lactamase, elastase, hyaluronidase, chondroitin sulfatase, and coagulase were not detected in any of the strains. DNase may be used to differentiate between the two subspecies. PMID:8370761

Amoako, K K; Goto, Y; Shinjo, T

1993-01-01

16

Isoquinoline alkaloids from Berberis Vulgaris subsp. Australis  

Microsoft Academic Search

Sixteen isoquinoline alkaloids were isolated from Berberis vulgaris subsp. australis. In addition to quaternary protoberberines and bisbenzylisoquinolines, a new seco-bisbenzylisoquinoline, (-)-tejedine, is reported.

Rafael Suau; Rodrigo Rico; J. Manuel López-Romero; Francisco Nájera; Ana Cuevas

1998-01-01

17

Effects of fertilization on the vascular ground vegetation of European beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Lieb.) stands  

E-print Network

pubescens Fagus sylvatica Holcus lanatus Picea abies Poa nemoralis Poa trivialis Quercus sp. Rubuspubescens Fagus sylvatica Holcus lanatus Lapsana communis Picea abies Poa nemoralis Poa trivialis Quercus sp. Rubus

Misson, Laurent

2001-01-01

18

Enterobacter hormaechei subsp. oharae subsp. nov., E. hormaechei subsp. hormaechei comb. nov., and E. hormaechei subsp. steigerwaltii subsp. nov., Three New Subspecies of Clinical Importance  

PubMed Central

Six species and six additional genovars are combined within the so-called Enterobacter cloacae complex, with one of them being the species Enterobacter hormaechei. In a recent population genetic study, two genetic clusters were found in close phylogenetic proximity to the genetic cluster of E. hormaechei. In order to prove the hypothesis that these three genetic clusters belong to the same species, we performed cross-hybridization experiments in microplates with DNAs of representatives of each genetic cluster. The close phylogenetic relationship among the clusters was reflected by their relatively low ?Tm values, ranging from 0.3 to 4.8, confirming the hypothesis that the clusters are parts of the same species. These clusters can be distinguished from the other species of the E. cloacae complex, which have ?Tm values of 5.6 to 10.3. Forty-eight E. hormaechei strains from the different genetic clusters were phenotypically characterized with 129 biochemical tests. In this way, E. hormaechei could be differentiated from the other species of the E. cloacae complex because it tests negative in the 3-hydroxy-butyrate test. The three genetic clusters of E. hormaechei could also be differentiated from each other by using phenotypic tests. Hence, we propose three new subspecies of E. hormaechei corresponding to genetic clusters VI, VII, and VIII of the E. cloacae complex. E. hormaechei subsp. hormaechei comb. nov. corresponds to the original species description, as it gives negative results for the adonitol, d-arabitol, d-sorbitol, and d-melibiose tests and a positive result for the dulcitol test. E. hormaechei subsp. oharae subsp. nov. gives negative results for the dulcitol, adonitol, and d-arabitol tests and positive results for the d-sorbitol and d-melibiose tests. E. hormaechei subsp. steigerwaltii subsp. nov. gives a negative result for the dulcitol test and positive results for the adonitol, d-arabitol, d-sorbitol, and d-melibiose tests. Among the members of the E. cloacae complex, E. hormaechei seems to be the species most frequently recovered from clinical specimens. PMID:16000451

Hoffmann, Harald; Stindl, Sibylle; Ludwig, Wolfgang; Stumpf, Anita; Mehlen, Andre; Monget, Daniel; Pierard, Denis; Ziesing, Stefan; Heesemann, Jürgen; Roggenkamp, Andreas; Schleifer, Karl H.

2005-01-01

19

Variation in susceptibility of beech (Fagus spp) to beech scale (Cryptococcus  

E-print Network

Variation in susceptibility of beech (Fagus spp) to beech scale (Cryptococcus D. R. Forestry are presented showing clonal differences in severity of attack by Cryptococcus fagisuga on beech scions in three seed orchards in southern England. These differences may be due to genetically controlled resistance

Paris-Sud XI, Université de

20

Genetic variability of Fagus sylvatica L. in Italy: the role of postglacial recolonization  

Microsoft Academic Search

Genetic variability of 21 Italian populations of beech (Fagus sylvatica L.) was studied using starch gel electrophoresis and nine polymorphic enzyme gene loci. Expected mean heterozygosity varied from 13.6 per cent to 20.3 per cent. Observed heterozygosity was less than expected in all but two populations. No association between allele frequencies and soil type or altitude was found. As in

Stefano Leonardi; Paolo Menozzi

1995-01-01

21

Amlioration de la germination des fanes (Fagus silvatica) par prtraitement en prsence de polythylne glycol  

E-print Network

Amélioration de la germination des faînes (Fagus silvatica) par prétraitement en présence de méthode permet une augmentation simultanée du taux et de la vitesse de germination. Il s'agit là de froid humide pouvant durer de 1 à 3 mois. Semées sans prétraitement, leur germination est très faible et

Paris-Sud XI, Université de

22

PHYLOGENETIC RELATIONSHIPS OF NEONECTRIA/CYLINDROCARPON ON FAGUS IN NORTH AMERICA  

Technology Transfer Automated Retrieval System (TEKTRAN)

The relationship of two species of Neonectria associated with beech bark canker in North America was evaluated by comparing isolates of these and additional species on Fagus in the Neonectria coccinea group. Gene regions in the translation elongation factor 1-alpha (EF1-'), RNA polymerase II secon...

23

Molecular Characterization of Copper Resistance Genes from Xanthomonas citri subsp. citri and Xanthomonas alfalfae subsp. citrumelonis?  

PubMed Central

Copper sprays have been widely used for control of endemic citrus canker caused by Xanthomonas citri subsp. citri in citrus-growing areas for more than 2 decades. Xanthomonas alfalfae subsp. citrumelonis populations were also exposed to frequent sprays of copper for several years as a protective measure against citrus bacterial spot (CBS) in Florida citrus nurseries. Long-term use of these bactericides has led to the development of copper-resistant (Cur) strains in both X. citri subsp. citri and X. alfalfae subsp. citrumelonis, resulting in a reduction of disease control. The objectives of this study were to characterize for the first time the genetics of copper resistance in X. citri subsp. citri and X. alfalfae subsp. citrumelonis and to compare these organisms to other Cur bacteria. Copper resistance determinants from X. citri subsp. citri strain A44(pXccCu2) from Argentina and X. alfalfae subsp. citrumelonis strain 1381(pXacCu2) from Florida were cloned and sequenced. Open reading frames (ORFs) related to the genes copL, copA, copB, copM, copG, copC, copD, and copF were identified in X. citri subsp. citri A44. The same ORFs, except copC and copD, were also present in X. alfalfae subsp. citrumelonis 1381. Transposon mutagenesis of the cloned copper resistance determinants in pXccCu2 revealed that copper resistance in X. citri subsp. citri strain A44 is mostly due to copL, copA, and copB, which are the genes in the cloned cluster with the highest nucleotide homology (?92%) among different Cur bacteria. PMID:21515725

Behlau, Franklin; Canteros, Blanca I.; Minsavage, Gerald V.; Jones, Jeffrey B.; Graham, James H.

2011-01-01

24

A record of Holocene environmental and ecological changes from Wildwood Lake,  

E-print Network

sediments represent European agricultural activities. However, unlike charcoal records from southern New and eastern Long Island; (2) the distribution of Fagus grandifolia (American beech) along the Northeast coast

Oswald, Wyatt

25

Eubacterium yurii subsp. schtitka subsp. nov.: Test Tube Brush Bacteria from Subgingival Dental Plaque  

Microsoft Academic Search

Representative strains of the test tube brush bacterium Eubacterium yurii, previously recovered from subgingival dental plaque of chronic adult periodontitis patients, were examined by determining their serological reactivities, protein electrophoretic patterns, deoxyribonucleic acid homologies, and bone resorp- tive activities in vitro. Our results indicate the existence of a third subspecies, E. yurii subsp. schtitka subsp. nov., in addition to the

BARBARA S. MARGARET; GEORGE N. KRYWOLAP

26

Common Genomic Features of Campylobacter jejuni subsp. doylei Strains Distinguish Them from C. jejuni subsp. jejuni  

Technology Transfer Automated Retrieval System (TEKTRAN)

Campylobacter jejuni has been divided into two subspecies: C. jejuni subsp. jejuni (Cjj) and C. jejuni subsp. doylei (Cjd). Nearly all of the C. jejuni strains isolated are Cjj; nevertheless, although Cjd strains are isolated infrequently, they differ from Cjj in two key aspects: they are obtained ...

27

Geographic distribution of chloroplast variation in Italian populations of beech ( Fagus sylvatica L.)  

Microsoft Academic Search

The distribution of chloroplast DNA (cpDNA) variation in Italian beech (Fagus sylvatica L.) populations was studied using PCR-RFLP and microsatellite markers. In total, 67 populations were analysed, and 14 haplotypes were identified by combining the two marker types. A remarkable subdivision of cpDNA diversity in Italian beech was found, as indicated by a high level of genetic differentiation (Gst=0.855). The

C. Vettori; G. G. Vendramin; M. Anzidei; R. Pastorelli; D. Paffetti; R. Giannini

2004-01-01

28

Contribution to the nomenclatural knowledge of Fagus sylvatica woodlands of southern Italy  

Microsoft Academic Search

The present paper deals with some nomenclatural notes regarding two important southern Italian beech phytosociological associations such as Aquifolio-Fagetum and Asyneumato-Fagetum which were described about 30 years ago and which still represent the most widespread Fagus sylvatica communities in southern Italy. According to the ICPN, Aquifolio-Fagetum is confirmed to be a nomen illegitimum. This name must be substituted with the

R Di Pietro; J Izco; C Blasi

2004-01-01

29

Assessment of genetic relationships and population discrimination among Fagus sylvatica L. by RAPD  

Microsoft Academic Search

We assessed the genetic relationships between members of the Fagaceae family by RAPDs in order to better ascertain the taxonomic status of a very particular population of Fagus sylvatica, the ‘tortuosa’ variety. Intra- and inter-population Nei and Li’s mean genetic distances were compared, and the genetic relationships\\u000a between individuals were clarified on dendrograms by the Neighbor joining method. RAPD analysis

A. Gallois; J. C. Audran; M. Burrus

1998-01-01

30

Leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech ( Fagus sylvatica )  

Microsoft Academic Search

We hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the European\\u000a beech (Fagus sylvatica) and increasing tree species diversity in the generally beech-dominated Central European temperate deciduous forests due\\u000a to an increase in litter quality. We studied the decomposition of leaf litter including its lignin fraction in monospecific\\u000a (pure beech) stands

Mascha Jacob; Karin Viedenz; Andrea Polle; Frank M. Thomas

2010-01-01

31

Does low soil base saturation affect fine root properties of European beech ( Fagus sylvatica L.)?  

Microsoft Academic Search

It is generally believed that high soil solution Al3+ in acidic soils with low base saturation (BS), negatively influences the properties of fine roots. Fine roots from European\\u000a beech (Fagus sylvatica L.) trees growing in highly acidic soils with very low BS and potentially high Al3+ concentration in the soil solution were analysed and the dependency of fine root properties

Anika K. Richter; Lorenz Walthert; Emmanuel Frossard; Ivano Brunner

2007-01-01

32

Microbial biomass phosphorus in soils of beech ( Fagus sylvatica L.) forests  

Microsoft Academic Search

Thirty-eight soils from forest sites in central Germany dominated by beech trees (Fagus sylvatica L.) were sampled to a depth of about 10 cm after careful removal of the overlying organic layers. Microbial biomass P was estimated by the fumigation — extraction method, measuring the increase in NaHCO3-extractable phosphate. The size of the microbial P pool varied between 17.7 and

Rainer G. Joergensen; Helga Kübler; Brunk Meyer; Volkmar Wolters

1995-01-01

33

Risk assessment of ozone impact on Fagus crenata in Japan: consideration of atmospheric nitrogen deposition  

Microsoft Academic Search

Tropospheric ozone (O3) is considered to be the air pollutant relating to the decline of Fagus crenata forest in Japan. In the present study, we assessed a risk of O3 impact on the growth of F. crenata in Japan, giving consideration to the effects associated with atmospheric nitrogen (N) deposition based on the experimental\\u000a study, national monitoring data for oxidant

Makoto Watanabe; Masahiro Yamaguchi; Hideyuki Matsumura; Yoshihisa Kohno; Takeshi Izuta

34

Genome Sequences of the Listeria ivanovii subsp. ivanovii Type Strain and Two Listeria ivanovii subsp. londoniensis Strains  

PubMed Central

We present the complete genomes of Listeria ivanovii subsp. ivanovii WSLC 3010 (ATCC 19119T), Listeria ivanovii subsp. londoniensis WSLC 30151 (SLCC 8854), and Listeria ivanovii subsp. londoniensis WSLC 30167 (SLCC 6032), representing the type strain of the species and two strains of the same serovar but different properties, respectively. PMID:25614561

Hupfeld, Mario; Fouts, Derrick E.; Loessner, Martin J.

2015-01-01

35

Comparative chemical composition of Agastache mexicana subsp. mexicana and A. mexicana subsp. xolocotziana  

Microsoft Academic Search

A comparative chemical analysis of Agastache mexicana subsp. mexicana and A. mexicana subsp. xolocotziana reveals that their methanol extracts constituents were very similar, with acacetin and (2-acetyl)-7-O-glucosyl acacetin being the most abundant compounds obtained. These results are consistent with the information reported for other species of Agastache. However, GS-MS analyses showed that methyl chavicol, limonene and linalool were the main

Rosa Estrada-Reyes; Eva Aguirre Hernández; Aída García-Argáez; Marcos Soto Hernández; Edelmira Linares; Robert Bye; Gerardo Heinze; Mariano Martínez-Vázquez

2004-01-01

36

Comparative phytochemical and antimicrobial investigations of Hypericum perforatum L. subsp. perforatum and H. perforatum subsp. angustifolium (DC.) Gaudin.  

PubMed

The aerial parts of H. perforatum subsp. perforatum and H. perforatum subsp. angustifolium were investigated for their chemical composition and antimicrobial activity. Spectrophotometric analysis indicated that H. perforatum subsp. perforatum is richer in flavonoids and tannins than the other subspecies. HPLC analysis confirmed the higher yield of flavonoids in H. perforatum subsp. perforatum and gave also a higher content of phenolic acids. H. perforatum subsp. angustifolium contained more hypericin. The presence of rutin was proven only in H. perforatum subsp. perforatum. The antimicrobial activity of the extracts of both subspecies was evaluated based on the inhibition zone diameters using the hole-plate diffusion method. The MeOH extracts, dichloromethane and petroleum ether fractions were effective against Staphylococcus aureus, S. epidermidis, Enterococcus faecalis and Bacillus subtilis. The results indicate that H. perforatum subsp. angustifolium had a stronger antimicrobial effect than the other subspecies. PMID:19831284

Males, Zeljan; Brantner, Adelheid H; Sovi?, Katarina; Pilepi?, Kroata Hazler; Plazibat, Misko

2006-09-01

37

Fatal Rickettsia conorii subsp. israelensis Infection, Israel  

PubMed Central

Underdiagnosis of fatal spotted fever may be attributed to nonspecific clinical features and insensitive acute-phase serologic studies. We describe the importance of molecular and immunohistochemical methods in establishing the postmortem diagnosis of locally acquired Israeli spotted fever due to Rickettsia conorii subsp. israelensis in a traveler returning to Israel from India. PMID:18439372

Keysary, Avi; Sandbank, Judith; Zaidenstein, Ronit; Itzhaki, Avi; Strenger, Carmela; Leitner, Moshe; Paddock, Christopher D.; Eremeeva, Marina E.

2008-01-01

38

The first closed genome sequence of Campylobacter fetus subsp. venerealis biovar intermedius  

Technology Transfer Automated Retrieval System (TEKTRAN)

Campylobacter fetus venerealis biovar intermedius is a variant of Campylobacter fetus subsp. venerealis, the causative agent of Bovine Genital Campylobacteriosis. In contrast to Campylobacter fetus subsp. venerealis which is restricted to the genital tract of cattle, Campylobacter fetus subsp. vener...

39

Fluorescence In Situ Hybridization Using Peptide Nucleic Acid Probes for Rapid Detection of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis in Potable-Water Biofilms  

Microsoft Academic Search

Here, we present for the first time a high-affinity peptide nucleic acid (PNA) oligonucleotide sequence for detecting Mycobacterium avium bacteria, including the opportunistically pathogenic subspecies M. avium subsp. avium, M. avium subsp. paratuberculosis, and M. avium subsp. silvaticum, by the fluorescence in situ hybrid- ization (FISH) method. There is evidence that M. avium subsp. avium especially is able to survive

Markku J. Lehtola; Eila Torvinen; Ilkka T. Miettinen; C. William Keevil

2006-01-01

40

Antibacterial Activity of Alkyl Gallates against Xanthomonas citri subsp. citri  

PubMed Central

The plant-pathogenic bacterium Xanthomonas citri subsp. citri is the causal agent of Asiatic citrus canker, a serious disease that affects all the cultivars of citrus in subtropical citrus-producing areas worldwide. There is no curative treatment for citrus canker; thus, the eradication of infected plants constitutes the only effective control of the spread of X. citri subsp. citri. Since the eradication program in the state of São Paulo, Brazil, is under threat, there is a clear risk of X. citri subsp. citri becoming endemic in the main orange-producing area in the world. Here we evaluated the potential use of alkyl gallates to prevent X. citri subsp. citri growth. These esters displayed a potent anti-X. citri subsp. citri activity similar to that of kanamycin (positive control), as evaluated by the resazurin microtiter assay (REMA). The treatment of X. citri subsp. citri cells with these compounds induced altered cell morphology, and investigations of the possible intracellular targets using X. citri subsp. citri strains labeled for the septum and centromere pointed to a common target involved in chromosome segregation and cell division. Finally, the artificial inoculation of citrus with X. citri subsp. citri cells pretreated with alkyl gallates showed that the bacterium loses the ability to colonize its host, which indicates the potential of these esters to protect citrus plants against X. citri subsp. citri infection. PMID:23104804

Silva, I. C.; Regasini, L. O.; Petrônio, M. S.; Silva, D. H. S.; Bolzani, V. S.; Belasque, J.; Sacramento, L. V. S.

2013-01-01

41

Antibacterial activity of alkyl gallates against Xanthomonas citri subsp. citri.  

PubMed

The plant-pathogenic bacterium Xanthomonas citri subsp. citri is the causal agent of Asiatic citrus canker, a serious disease that affects all the cultivars of citrus in subtropical citrus-producing areas worldwide. There is no curative treatment for citrus canker; thus, the eradication of infected plants constitutes the only effective control of the spread of X. citri subsp. citri. Since the eradication program in the state of São Paulo, Brazil, is under threat, there is a clear risk of X. citri subsp. citri becoming endemic in the main orange-producing area in the world. Here we evaluated the potential use of alkyl gallates to prevent X. citri subsp. citri growth. These esters displayed a potent anti-X. citri subsp. citri activity similar to that of kanamycin (positive control), as evaluated by the resazurin microtiter assay (REMA). The treatment of X. citri subsp. citri cells with these compounds induced altered cell morphology, and investigations of the possible intracellular targets using X. citri subsp. citri strains labeled for the septum and centromere pointed to a common target involved in chromosome segregation and cell division. Finally, the artificial inoculation of citrus with X. citri subsp. citri cells pretreated with alkyl gallates showed that the bacterium loses the ability to colonize its host, which indicates the potential of these esters to protect citrus plants against X. citri subsp. citri infection. PMID:23104804

Silva, I C; Regasini, L O; Petrônio, M S; Silva, D H S; Bolzani, V S; Belasque, J; Sacramento, L V S; Ferreira, H

2013-01-01

42

Bacteriological and Molecular Detection of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus in Equines of Northern India  

PubMed Central

Present study was undertaken to study the prevalence of ?-haemolytic streptococci in equine of northern temperate region of Jammu and Kashmir, India. One hundred and forty one samples were collected in duplicate from nasopharyngeal tract of diseased (53) and apparently healthy equine (88) for isolation and direct PCR. A total of 77 isolates of streptococci were recovered from 141 samples with an overall prevalence rate of 54.60%. Out of these 77 isolates, 52 were from diseased and 25 from apparently healthy animals. Of the 77 isolates, 4 were identified as Streptococcus equi subsp. equi, 56 as S. equi subsp. zooepidemicus and 17 as S. dysgalactiae subsp. equisimilis. Thus the overall prevalence of S. equi subsp. equi, S. equi subsp. zooepidemicus and S. dysgalactiae subsp. equisimilis was 2.83, 39.71 and 12.05% respectively. The sensitivity of the PCR for the detection of S. equi species was found higher when attempted from direct swab samples. PMID:24834002

MIR, Irfan Ahmad; KUMAR, Bablu; TAKU, Anil; FARIDI, Farah; BHAT, Mohd. Altaf; BABA, Naseer Ahmad; MAQBOOL, Tahir

2013-01-01

43

Bartonella vinsonii subsp. arupensis in Humans, Thailand  

PubMed Central

We identified Bartonella vinsonii subsp. arupensis in pre-enriched blood of 4 patients from Thailand. Nucleotide sequences for transfer-messenger RNA gene, citrate synthase gene, and the 16S–23S rRNA internal transcribed spacer were identical or closely related to those for the strain that has been considered pathogenic since initially isolated from a human in Wyoming, USA. PMID:22607728

Kosoy, Michael Y.; Diaz, Maureen H.; Winchell, Jonas; Baggett, Henry; Maloney, Susan A.; Boonmar, Sumalee; Bhengsri, Saithip; Sawatwong, Pongpun; Peruski, Leonard F.

2012-01-01

44

Frequency of inversions affects senescence phenology of Acer pseudoplatanus and Fagus sylvatica  

NASA Astrophysics Data System (ADS)

In mountainous regions, inversion situations with cold-air pools in the valleys occur frequently, especially in fall and winter. With the accumulation of inversion days, trees in lower elevations experience lower temperature sums than those in middle elevations. In a two-year observational study, deciduous trees, such as Acer pseudoplatanus and Fagus sylvatica, on altitudinal transects responded in their fall leaf senescence phenology. Phenological phases were advanced and senescence duration was shortened by the cold temperatures in the valley. This effect was more distinct for late phases than for early phases since they experienced more inversion days. The higher the inversion frequency, the stronger the signal was. Acer pseudoplatanus proved to be more sensitive to cold temperatures compared to Fagus sylvatica. We conclude that cold-air pools have a considerable impact on the vegetation period of deciduous trees. Considering this effect, trees in the mid hillside slopes gain advantages compared to lower elevations. Our findings will help to improve knowledge about ecological drivers and responses in mountainous forest ecosystems.

Schuster, Christina; Kirchner, Manfred; Jakobi, Gert; Menzel, Annette

2014-05-01

45

Fine roots in stands of Fagus sylvatica and Picea abies along a gradient of soil acidification.  

PubMed

Root length of naturally grown young beech trees (Fagus sylvatica L.) was investigated in 26 forest plots of differing base saturation and nitrogen deposition. The relative length of finest roots (<0.25 mm) was found to decrease in soils with low base saturation. A similar reduction of finest roots in plots with high nitrogen deposition was masked by the effect of base saturation. The formation of adventitious roots was enhanced in acidic soils. The analysis of 128 soil profiles for fine roots of all species present in stands of either Fagus sylvatica L., Picea abies [Karst.] L. or both showed a decreased rooting depth in soils with < or =20% base saturation and in hydromorphic soils. For base rich, well drained soils an average rooting depth of 108 cm was found. This decreased by 28 cm on acidic, well drained soils. The results suggest an effect of the current soil acidification in Switzerland and possibly also of nitrogen deposition on the fine root systems of forest trees. PMID:15964116

Braun, Sabine; Cantaluppi, Leonardo; Flückiger, Walter

2005-10-01

46

Microsatellite polymorphism of Siebold's beech (Fagus crenata Blume) at five National Forest Reserves in the Oshima Peninsula, southern Hokkaido  

Microsoft Academic Search

Siebold's beech (Fagus crenata) is a dominant tree species of cool temperate forest ecosystems in southern Hokkaido, and is one of the most important timber species in the Oshima Peninsula. Several beech forests have been designated as forest reserves in the Oshima Peninsula, however the genetic diversity of these forest reserves has not yet been evaluated. We evaluated the genetic

Makoto KOBAYASHI; Keiko KITAMURA; Takayuki KAWAHARA

2009-01-01

47

Adenine nucleotides and energy charge during dormancy breaking in embryo axes of Acer platanoides and Fagus sylvatica seeds  

Microsoft Academic Search

We analysed changes in AMP, ADP, and ATP concentrations and adenylate energy charge in Norway maple (Acer platanoides L.) and European beech (Fagus sylvatica L.) seeds during dormancy breaking (at 3 °C) and in the control variant at 15 °C. Values of the studied indicators in stratified\\u000a beech seeds were generally higher at 15 °C, at least until germination (+3

Kazimierz Krawiarz; Zofia Szczotka

2005-01-01

48

IMMUNOREACTIVITY OF THE MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS 19-KDA LIPOPROTEIN  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background The Mycobacterium tuberculosis 19-kDa lipoprotein has been reported to stimulate both T and B cell responses as well as induce a number of Th1 cytokines. In order to evaluate the Mycobacterium avium subsp. paratuberculosis (M. avium subsp. paratuberculosis) 19-kDa lipoprotein as an immun...

49

Draft Genome Sequence of Mycobacterium abscessus subsp. bolletii INCQS 00594  

PubMed Central

An epidemic of surgical-site infections by a single strain of Mycobacterium abscessus subsp. bolletii affected >1,700 patients in Brazil from 2004 to 2008. The genome of the epidemic prototype strain M. abscessus subsp. bolletii INCQS 00594, deposited in the collection of the National Institute for Health Quality Control (INCQS), was sequenced. PMID:24201191

Leão, Sylvia Cardoso; Matsumoto, Cristianne Kayoko; Viana-Niero, Cristina; Ramos, Rommel Thiago Jucá; Carneiro, Adriana Ribeiro; Barbosa, Maria Silvanira; Lima, Karla Valéria Batista; Lopes, Maria Luiza; Azevedo, Vasco

2013-01-01

50

Streptococcus gallolyticus subsp. pasteurianus Infection in Twin Infants.  

PubMed

Streptococcus gallolyticus subsp. pasteurianus, previously known as Streptococcus bovis biotype II.2, is an uncommon pathogen in neonates. Nevertheless, it can cause severe neonatal sepsis and meningitis often clinically indistinguishable from those caused by group B streptococci and has been associated with considerable morbidity. We report the first known cases of S. gallolyticus subsp. pasteurianus infection in twin infants. PMID:25609731

Hede, Sannya Vidyadhar; Olarte, Liset; Chandramohan, Lakshmi; Kaplan, Sheldon L; Hulten, Kristina G

2015-04-01

51

Mycobacterium abscessus subsp abscessus lung disease: ‘trouble ahead, trouble behind…’  

PubMed Central

Mycobacterium abscessus subsp abscessus is the most common respiratory pathogen among the rapidly growing non-tuberculous mycobacteria (NTM) and is also the most feared due to its well-deserved reputation for being refractory to antibiotic therapy. M. abscessus subsp abscessus has multiple innate antibiotic resistance mechanisms, but the most important one described so far is an inducible erythromycin methylase (erm) gene. M. abscessus subsp abscessus isolates may appear macrolide susceptible on initial in vitro testing but become macrolide resistant after exposure to macrolide. It is therefore very important to test clinically significant M. abscessus subsp abscessus isolates for erm gene activity. Remarkably, controversy still exists about the taxonomy and nomenclature of M. abscessus subspecies including subsp abscessus, subsp massiliense and subsp bolletii. Identification of these subspecies is not moot as M. abscessus subsp massiliense does not have an active erm gene resulting in both in vitro and in vivo susceptibility to macrolide. It is imperative from the clinician's perspective that mycobacterial laboratories correctly and rapidly identify M. abscessus to the subspecies level. Unfortunately, there are no reliably or predictably effective treatment regimens for M. abscessus subsp abscessus and better, more effective antimicrobial agents are badly needed. Surgical resection of involved lung tissue as an adjunct to antibiotic therapy is beneficial in selected patients but cannot be broadly applied. Overall, M. abscessus subsp abscessus remains a formidable respiratory mycobacterial pathogen, one that we are only beginning to understand microbiologically and one that as yet consistently evades our best efforts at successful therapeutic outcomes. ‘trouble ahead, trouble behind, and you know that notion just crossed my mind’. Casey Jones, Grateful Dead (1970) PMID:25580261

2014-01-01

52

Proposal to rename Carnobacterium inhibens as Carnobacterium inhibens subsp. inhibens subsp. nov. and description of Carnobacterium inhibens subsp. gilichinskyi subsp. nov., a psychrotolerant bacterium isolated from Siberian permafrost.  

PubMed

A novel, psychrotolerant facultative anaerobe, strain WN1359(T), was isolated from a permafrost borehole sample collected at the right bank of the Kolyma River in Siberia, Russia. Gram-positive-staining, non-motile, rod-shaped cells were observed with sizes of 1-2 µm long and 0.4-0.5 µm wide. Growth occurred in the range of pH 5.8-9.0 with optimal growth at pH 7.8-8.6 (pH optimum 8.2). The novel isolate grew at temperatures from 0-37 °C and optimal growth occurred at 25 °C. The novel isolate does not require NaCl; growth was observed between 0 and 8.8?% (1.5 M) NaCl with optimal growth at 0.5?% (w/v) NaCl. The isolate was a catalase-negative, facultatively anaerobic chemo-organoheterotroph that used sugars but not several single amino acids or dipeptides as substrates. The major metabolic end-product was lactic acid in the ratio of 86?% l-lactate?:?14?% d-lactate. Strain WN1359(T) was sensitive to ampicillin, chloramphenicol, fusidic acid, lincomycin, monocycline, rifampicin, rifamycin SV, spectinomycin, streptomycin, troleandomycin and vancomycin, and resistant to nalidixic acid and aztreonam. The fatty acid content was predominantly unsaturated (70.2?%), branched-chain unsaturated (11.7?%) and saturated (12.5?%). The DNA G+C content was 35.3 mol% by whole genome sequence analysis. 16S rRNA gene sequence analysis showed 98.7?% sequence identity between strain WN1359(T) and Carnobacterium inhibens. Genome relatedness was computed using both Genome-to-Genome Distance Analysis (GGDA) and Average Nucleotide Identity (ANI), which both strongly supported strain WN1359(T) belonging to the species C. inhibens. On the basis of these results, the permafrost isolate WN1359(T) represents a novel subspecies of C. inhibens, for which the name Carnobacterium inhibens subsp. gilichinskyi subsp. nov. is proposed. The type strain is WN1359(T) (?=?ATCC BAA-2557(T)?=?DSM 27470(T)). The subspecies Carnobacterium inhibens subsp. inhibens subsp. nov. is created automatically. An emended description of C. inhibens is also provided. PMID:25392348

Nicholson, Wayne L; Zhalnina, Kateryna; de Oliveira, Rafael R; Triplett, Eric W

2015-02-01

53

Hypoglycemic constituents of Gynura divaricata subsp. formosana.  

PubMed

Gynura divaricata Kitam. subsp. formosana is a folk medicine used as a hypoglycemic agent for diabetes patients in Taiwan. Guided by the hexose transport assay, the hypoglycemic constituents of the aerial part of this plant were disclosed through chromatographic methods. They are fructooligosaccharides, including beta-D-fructofuranose, sucrose, 1-kestose, nystose, and 1(F)-beta-fructofuranosylnystose. The hexose transport assay indicated that nystose was the most potent among these compounds, showing a 46.7% difference from pinitol in the stimulation index at a concentration of 0.5 mg/mL. PMID:22474963

Chou, Shen-Chieh; Chuang, Lee-Ming; Lee, Shoei-Sheng

2012-02-01

54

Ophiostoma arduennense sp. nov. (Ophiostomatales, Ascomycota) from Fagus sylvatica in southern Belgium.  

PubMed

Ophiostoma arduennense sp. nov. is described from several cultures isolated from Fagus sylvatica in southern Belgium. The species is mainly characterized by globose perithecia with small button-like bases ornamented with brown hyphal hairs of variable length and, long cylindrical necks ending in ostiolate hyphae. It is homothallic with small reniform ascospores and no apparent anamorph. It is closely associated with the ambrosia beetles Xyloterus domesticus and X. signatus. Its phylogenetic relationships within Ophiostoma are discussed and the species is compared with other Ophiostoma species associated with European beech or other broad-leaved trees in Europe, especially species of the O. quercus-O. piceae complex. The species is responsible for a dark brown staining of the sapwood and its role in the decline of beech in Southern Belgium is also discussed. PMID:16828272

Carlier, François-Xavier; Decock, Cony; Jacobs, Karin; Maraite, Henri

2006-07-01

55

The cough suppressive activity of sulfated glucuronoxylan from Fagus sylvatica L.  

PubMed

Hemicellulose polysaccharides represent a large group of natural renewable polymers, however, their application potency is still low. In our study a hardwood 4-O-methylglucuronoxylan was isolated by alkali peroxide extraction of Fagus sylvatica sawdust and modified into sulfated water soluble derivative (MGXS). Highly sulfated MGXS was characterized by HPLC, FTIR and NMR spectroscopies, and tested in vivo on chemically induced cough reflex and smooth muscles reactivity. Farmacological tests revealed an interesting antitussive activity of MGXS. Comparative tests with drug commonly used in a clinical practice revealed that antitussive activity of MGXS was lower than that of opioid receptor agonist codeine, the strongest antitussive drug. Furthermore, the specific reactivity of airways smooth muscle was not significantly affected by MGXS, indicating thus that the polymer is not involved in the bronchodilation process. PMID:24680903

Nosá?ova, G; Jure?ek, L; Turjan, J; Capek, P; Prisenž?áková, L; Fra?ová, S

2014-06-01

56

Modeling stomatal conductance and ozone uptake of Fagus crenata grown under different nitrogen loads.  

PubMed

A multiplicative stomatal conductance model was constructed to estimate stomatal O3 uptake of Fagus crenata exposed to O3 under different N loads to the soil. Our stomatal conductance model included environmental functions such as the stomatal responses of F. crenata to diurnal changes, chronic O3 stress (AOT0), acute O3 stress (O3 concentration), and nitrogen load to soil. The model could explain 62% of the variability in stomatal conductance. We suggest therefore that stomatal closure induced by O3 and N load-induced soil acidification must be taken into account in developing a stomatal conductance model for estimating stomatal O3 uptake for future risk assessment of O3 impact on Japanese forest tree species such as F. crenata. PMID:24134917

Azuchi, Fumika; Kinose, Yoshiyuki; Matsumura, Tomoe; Kanomata, Tomoaki; Uehara, Yui; Kobayashi, Ayumi; Yamaguchi, Masahiro; Izuta, Takeshi

2014-01-01

57

Do variations in leaf phenology affect radial growth variations in Fagus sylvatica?  

PubMed

We used a dendrochronological and leaf phenology network of European beech (Fagus sylvatica) in Slovenia, a transitional area between Mediterranean, Alpine and continental climatic regimes, for the period 1955-2007 to test whether year to year variations in leaf unfolding and canopy duration (i.e. time between leaf unfolding and colouring) influence radial growth (annual xylem production and tree ring widths) and if such influences are more pronounced at higher altitudes. We showed that variability in leaf phenology has no significant effect on variations in radial growth. The results are consistent in the entire region, irrespective of the climatic regime or altitude, although previous studies have shown that leaf phenology and tree ring variation depend on altitude. The lack of relationship between year to year variability in leaf phenology and radial growth may suggest that earlier leaf unfolding-as observed in a previous study-probably does not cause increased tree growth rates in beech in Slovenia. PMID:25239517

Cufar, Katarina; De Luis, Martin; Prislan, Peter; Gri?ar, Jožica; Crepinšek, Zalika; Merela, Maks; Kajfež-Bogataj, Lu?ka

2014-09-20

58

Leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech (Fagus sylvatica).  

PubMed

We hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the European beech (Fagus sylvatica) and increasing tree species diversity in the generally beech-dominated Central European temperate deciduous forests due to an increase in litter quality. We studied the decomposition of leaf litter including its lignin fraction in monospecific (pure beech) stands and in stands with up to five tree genera (Acer spp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Tilia spp.) using a litterbag approach. Litter and lignin decomposition was more rapid in stand-representative litter from multispecific stands than in litter from pure beech stands. Except for beech litter, the decomposition rates of species-specific tree litter did not differ significantly among the stand types, but were most rapid in Fraxinus excelsior and slowest in beech in an interspecific comparison. Pairwise comparisons of the decomposition of beech litter with litter of the other tree species (except for Acer platanoides) revealed a "home field advantage" of up to 20% (more rapid litter decomposition in stands with a high fraction of its own species than in stands with a different tree species composition). Decomposition of stand-representative litter mixtures displayed additive characteristics, not significantly more rapid than predicted by the decomposition of litter from the individual tree species. Leaf litter decomposition rates were positively correlated with the initial N and Ca concentrations of the litter, and negatively with the initial C:N, C:P and lignin:N ratios. The results support our hypothesis that the overall decomposition rates are mainly influenced by the chemical composition of the individual litter species. Thus, the fraction of individual tree species in the species composition seems to be more important for the litter decomposition rates than tree species diversity itself. PMID:20596729

Jacob, Mascha; Viedenz, Karin; Polle, Andrea; Thomas, Frank M

2010-12-01

59

Drought-Adaptation Potential in Fagus sylvatica: Linking Moisture Availability with Genetic Diversity and Dendrochronology  

PubMed Central

Background Microevolution is essential for species persistence especially under anticipated climate change scenarios. Species distribution projection models suggested that the dominant tree species of lowland forests in Switzerland, European beech (Fagus sylvatica L.), might disappear from most areas due to expected longer dry periods. However, if genotypes at the moisture boundary of the species climatic envelope are adapted to lower moisture availability, they can serve as seed source for the continuation of beech forests under changing climates. Methodology/Principal Findings With an AFLP genome scan approach, we studied neutral and potentially adaptive genetic variation in Fagus sylvatica in three regions containing a dry and a mesic site each (nind.?=?241, nmarkers?=?517). We linked this dataset with dendrochronological growth measures and local moisture availabilities based on precipitation and soil characteristics. Genetic diversity decreased slightly at dry sites. Overall genetic differentiation was low (Fst?=?0.028) and Bayesian cluster analysis grouped all populations together suggesting high (historical) gene flow. The Bayesian outlier analyses indicated 13 markers with three markers differing between all dry and mesic sites and the others between the contrasting sites within individual regions. A total of 41 markers, including seven outlier loci, changed their frequency with local moisture availability. Tree height and median basal growth increments were reduced at dry sites, but marker presence/absence was not related to dendrochronological characteristics. Conclusion and Their Significance The outlier alleles and the makers with changing frequencies in relation to moisture availability indicate microevolutionary processes occurring within short geographic distances. The general genetic similarity among sites suggests that ‘preadaptive’ genes can easily spread across the landscape. Yet, due to the long live span of trees, fostering saplings originating from dry sites and grown within mesic sites might increase resistance of beech forests during the anticipated longer dry periods. PMID:22448260

Pluess, Andrea R.; Weber, Pascale

2012-01-01

60

Paired-End Sequence Mapping Detects Extensive Genomic Rearrangement and Translocation during Divergence of Francisella tularensis subsp. tularensis and Francisella tularensis subsp. holarctica Populations† ‡  

PubMed Central

Comparative genome hybridization of the Francisella tularensis subsp. tularensis and F. tularensis subsp. holarctica populations have shown that genome content is highly conserved, with relatively few genes in the F. tularensis subsp. tularensis genome being absent in other F. tularensis subspecies. To determine if organization of the genome differs between global populations of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica, we have used paired-end sequence mapping (PESM) to identify regions of the genome where synteny is broken. The PESM approach compares the physical distances between paired-end sequencing reads of a library of a wild-type reference F. tularensis subsp. holarctica strain to the predicted lengths between the reads based on map coordinates of two different F. tularensis genome sequences. A total of 17 different continuous regions were identified in the F. tularensis subsp. holarctica genome (CRholarctica) which are noncontiguous in the F. tularensis subsp. tularensis genome. Six of the 17 different CRholarctica are positioned as adjacent pairs in the F. tularensis subsp. tularensis genome sequence but are translocated in F. tularensis subsp. holarctica, implying that their arrangements are ancestral in F. tularensis subsp. tularensis and derived in F. tularensis subsp. holarctica. PCR analysis of the CRholarctica in 88 additional F. tularensis subsp. tularensis and F. tularensis subsp. holarctica isolates showed that the arrangements of the CRholarctica are highly conserved, particularly in F. tularensis subsp. holarctica, consistent with the hypothesis that global populations of F. tularensis subsp. holarctica have recently experienced a periodic selection event or they have emerged from a recent clonal expansion. Two unique F. tularensis subsp. tularensis-like strains were also observed which likely are derived from evolutionary intermediates and may represent a new taxonomic unit. PMID:16885459

Dempsey, Michael P.; Nietfeldt, Joseph; Ravel, Jacques; Hinrichs, Steven; Crawford, Robert; Benson, Andrew K.

2006-01-01

61

Regulation of Expression of Major Histocompatibility Antigens by Bovine Macrophages Infected with Mycobacterium avium subsp. paratuberculosis or Mycobacterium avium subsp. avium  

PubMed Central

Mycobacterium avium subsp. paratuberculosis and Mycobacterium avium subsp. avium are antigenically and genetically very similar organisms; however, they differ markedly in their virulence for cattle. We evaluated the capacity of bovine macrophages infected with M. avium subsp. paratuberculosis or M. avium subsp. avium to express major histocompatibility complex (MHC) class I and class II antigens on their surface and to interact with primed autologous lymphocytes. Our results indicate that infection of bovine macrophages with M. avium subsp. paratuberculosis promoted the downregulation of MHC class I and class II molecules on the macrophage surface within 24 and 12 h, respectively. Alternatively, MHC class II expression by M. avium subsp. avium-infected macrophages was not detected until 24 h after infection, and the magnitude of the decrease was smaller. Decreased MHC class I expression by M. avium subsp. avium-infected macrophages was not detected. Unlike M. avium subsp. paratuberculosis-infected macrophages, M. avium subsp. avium-infected macrophages upregulated MHC class I and class II expression after activation by gamma interferon or tumor necrosis factor alpha. Further, M. avium subsp. avium-infected macrophages were lysed by primed autologous lymphocytes, whereas M. avium subsp. paratuberculosis-infected macrophages were not. Overall, the results support the hypothesis that the difference in the virulence of M. avium subsp. paratuberculosis and M. avium subsp. avium for cattle is dependent on a difference in the capacity of the organisms to suppress mycobacterial antigen presentation to T lymphocytes. PMID:11159996

Weiss, Douglas J.; Evanson, Oral A.; McClenahan, David J.; Abrahamsen, Mitchell S.; Walcheck, Bruce K.

2001-01-01

62

Holocene expansions of Fagus silvatica and Abies alba in Central Europe: where are we after eight decades of debate?  

NASA Astrophysics Data System (ADS)

During the past eight decades contrasting hypotheses have been put forward to explain the Holocene expansions of Fagus silvatica (beech) and Abies alba (fir) in Central Europe. The hypotheses can be referred to as: (1) climatic change; (2) migrational lag; (3) delay in population increase; (4) human disturbance; and (5) fire disturbance. High-resolution pollen and charcoal records from three sites in lowland Switzerland and southern Germany allow testing the human vs. fire-disturbance hypotheses by means of time-series analysis. Cross-correlations between pairs of pollen as well as between microscopic charcoal and pollen suggest that neither human nor fire disturbance substantially promoted the expansion of Fagus and Abies. We address the remaining hypotheses (climatic change, migrational lag, delay of population increase) by a combined interpretation of our data with independent climatic records and other evidence of past environmental dynamics (e.g. dynamic vegetation modelling) for southern Central Europe. Rapid population expansions in response to cooling and precipitation increase suggest that climatic change was the main forcing factor and that migrational lags were not effective since at least 8200 cal. yr ago. On the basis of this conclusion we propose an explanatory model for the Holocene expansion of Fagus and Abies in Central Europe: Both trees expanded stepwise across the continent during favourable 8200-type events, which were characterized by changes towards wetter and cooler conditions and corresponded to previously recognized Holocene cold phases in Central Europe as well as in the North Atlantic realm. Asynchronous expansions across continental Europe are explained by analogy to today's precipitation gradients resulting from orographic effects. Response lags of Fagus and Abies to climatic change reached a few decades at most, whereas population expansion in response to climatic change lasted for several centuries, probably as a consequence of intrinsic rates of population increase as well as competition with previously established forest communities. This model is in agreement with recent data from northern Central Europe, where large-scale expansion pulses of Fagus coincided with 8200-type events (e.g. 3800-3400 and 2750-2350 cal. BP). In addition to climatic change, human impact influenced the expansions of Fagus in northern Central Europe. We suggest that Abies expansions across Europe after 5000 cal. BP were inhibited by human and/or fire disturbance.

Tinner, Willy; Lotter, André F.

2006-03-01

63

Short-sequence-repeat analysis of Mycobacterium avium subsp. paratuberculosis and Mycobacterium avium subsp. avium isolates collected from animals throughout the United States reveals both stability of loci and extensive diversity.  

PubMed

We analyzed the multilocus short sequence repeats (SSRs) of 211 and 56 isolates of Mycobacterium avium subsp. paratuberculosis and M. avium subsp. avium, respectively. The M. avium subsp. paratuberculosis isolates could be differentiated into 61 genotypes. The M. avium subsp. avium isolates showed limited diversity. These SSRs are stable and suitable for studying the molecular epidemiology of M. avium subsp. paratuberculosis. PMID:16891519

Harris, N Beth; Payeur, Janet B; Kapur, Vivek; Sreevatsan, Srinand

2006-08-01

64

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea  

PubMed Central

The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

2014-01-01

65

Breeding system of the annual Cruciferae, Arabidopsis kamchatica subsp. kawasakiana.  

PubMed

The breeding system of an annual Cruciferae, Arabidopsis kamchatica subsp. kawasakiana, was studied in three natural populations. We applied four experimental treatments, open pollination, bagging, emasculation + bagging, and emasculation + hand-pollination + bagging. None of the emasculated flowers with bags produced fruits but we observed high fruit sets in the other three treatments. The results confirmed that A. kamchatica subsp. kawasakiana is a self-compatible, non-apomictic species that can produce seeds through auto-pollination. Considering the life cycle as an annual, increased reproductive assurance through auto-pollination should be critical for the maintenance of populations of A. kamchatica subsp. kawasakiana. PMID:17982712

Sugisaka, Jiro; Kudoh, Hiroshi

2008-01-01

66

Ribotyping to differentiate Fusobacterium necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme isolated from bovine ruminal contents and liver abscesses.  

PubMed Central

Differences in biological activities (hemagglutination, hemolytic, leukotoxic, and virulence) and ribotypes between the two subspecies of Fusobacterium necrophorum of bovine ruminal and liver abscess origins were investigated. Hemagglutination activity was present in all hepatic, but only some ruminal, strains of Fusobacterium necrophorum subsp. necrophorum. Ruminal F. necrophorum subsp. necrophorum had low leukotoxin titers yet was virulent in mice. Fusobacterium necrophorum subsp. funduliforme of hepatic or ruminal origin had no hemagglutination activity, had low hemolytic and leukotoxic activities, and was less virulent to mice. For ribotyping, chromosomal DNAs of 10 F. necrophorum subsp. necrophorum and 11 F. necrophorum subsp. funduliforme isolates were digested with restriction endonucleases (EcoRI, EcoRV, SalI, PstI, and HaeIII) and examined by restriction fragment length polymorphisms after hybridizing with a digoxigenin-labeled cDNA probe transcribed from a mixture of 16 and 23S rRNAs from Escherichia coli. The most discriminating restriction endonuclease enzyme for ribotyping was EcoRI. The presence or absence of two distinct bands of 2.6 and 4.3 kb differentiated the two subspecies. Regardless of the origin, only F. necrophorum subsp. necrophorum, a virulent subspecies, had a ca. 2.6-kb band, whereas F. necrophorum subsp. funduliforme, a less virulent subspecies, had a ca. 4.3-kb band. Ribotyping appears to be a useful technique to genetically differentiate the two subspecies of F. necrophorum. PMID:8593050

Okwumabua, O; Tan, Z; Staats, J; Oberst, R D; Chengappa, M M; Nagaraja, T G

1996-01-01

67

Cell surface characteristics of Lactobacillus casei subsp. casei, Lactobacillus paracasei subsp. paracasei, and Lactobacillus rhamnosus strains.  

PubMed Central

Hydrophilic and electrostatic cell surface properties of eight Lactobacillus strains were characterized by using the microbial adhesion to solvents method and microelectrophoresis, respectively. All strains appeared relatively hydrophilic. The strong microbial adhesion to chloroform, an acidic solvent, in comparison with microbial adhesion to hexadecane, an apolar n-alkane, demonstrated the particularity of lactobacilli to have an important electron donor and basic character and consequently their potential ability to generate Lewis acid-base interactions with a support. Regardless of their electrophoretic mobility (EM), strains were in general slightly negatively charged at alkaline pH. A pH-dependent behavior concerning cell surface charges was observed. The EM decreased progressively with more acidic pHs for the L. casei subsp. casei and L. paracasei subsp. paracasei strains until the isoelectric point (IEP), i.e., the pH value for which the EM is zero. On the other hand, the EM for the L. rhamnosus strains was stable from pH 8 to pH 3 to 4, at which point there was a shift near the IEP. Both L. casei subsp. casei and L. paracasei subsp. paracasei strains were characterized by an IEP of around 4, whereas L. rhamnosus strains possessed a markedly lower IEP of 2. The present study showed that the cell surface physicochemical properties of lactobacilli seem to be, at least in part and under certain experimental conditions, particular to the bacterial species. Such differences detected between species are likely to be accompanied by some particular changes in cell wall chemical composition. PMID:9143109

Pelletier, C; Bouley, C; Cayuela, C; Bouttier, S; Bourlioux, P; Bellon-Fontaine, M N

1997-01-01

68

Comparisons of genetic and morphological distance with heterosis between Medicago sativa subsp. sativa and subsp. falcata  

Microsoft Academic Search

Biomass yield heterosis has been shown to exist between Medicago sativasubsp. sativa and Medica gosativa subsp. falcata. The objective of this study was to gain a better understanding of what morphological and genetic factors were most highly\\u000a correlated with total biomass yield heterosis. We calculated genetic distances among nine sativa and five falcate genotypes\\u000a based on amplified fragment length polymorphism

Heathcliffe Riday; E. Charles Brummer; T. Austin Campbell; Diane Luth; Patricia M. Cazcarro

2003-01-01

69

Quantifying ozone uptake and its effects on the stand level of common beech (Fagus sylvatica L.) in Southern Germany  

Microsoft Academic Search

Abstract Stand level O3 fluxes were calculated using water balance calculations for 21 Common,beech (Fagus sylvatica L.) stands and O3 data from 20 monitoring stations in Southern Germany. For this intention, the daily loss of water by evapotranspiration per stand area was set against the daily O3 uptake. During the last 30 years, O3 uptake ranges between 0 and 187

Christoph Dittmar; Klaus Pfaffelmoser; Thomas Ro Tzer; Wolfram Elling

70

Ozone sensitivity of Fagus sylvatica and Fraxinus excelsior young trees in relation to leaf structure and foliar ozone uptake  

Microsoft Academic Search

During the summer of 2001, 2-year-old Fraxinus excelsior and Fagus sylvatica plants were subjected to ozone-rich environmental conditions at the Regional Forest Nursery at Curno (Northern Italy). Atmospheric ozone concentrations and stomatal conductance were measured, in order to calculate the foliar fluxes by means of a one-dimensional model. The foliar structure of both species was examined (thickness of the lamina

Giacomo Gerosa; Riccardo Marzuoli; Filippo Bussotti; Marica Pancrazi; Antonio Ballarin-Denti

2003-01-01

71

Effects of climate on diameter growth of co-occurring Fagus sylvatica and Abies alba along an altitudinal gradient  

Microsoft Academic Search

In high-elevation forests, growth is limited by low temperatures, while in Mediterranean climates drought and high temperatures\\u000a are the main limiting factors. Consequently, the climate-growth relationships on Mont Ventoux, a mountain in the Mediterranean\\u000a area, are influenced by both factors. Two co-occurring species were studied: silver fir (Abies alba Mill.) and common beech (Fagus sylvatica L.), whose geographical distribution depends

Cailleret Maxime; Davi Hendrik

2011-01-01

72

Nanoscale Similarities in the Substructure of the Exines of FagusPollen Grains and LycopodiumSpores  

Microsoft Academic Search

The exine substructure of an angiosperm,Fagus sylvatica(beech) pollen and a pteridophyte,Lycopodium clavatum(a club moss) spore was investigated by scanning tunnelling microscopy. These pollen and spores, despite their distinct differences in structure and morphology on a micrometre scale, have very similar substructure on a nanometre scale. The substructure appears to consist of a multi-helix, i.e. a helical chain in turn wound

JESPER WITTBORN; K. V RAO; G EL-GHAZALY; J. R ROWLEY

1998-01-01

73

Crown plasticity and neighborhood interactions of European beech ( Fagus sylvatica L.) in an old-growth forest  

Microsoft Academic Search

Competition for canopy space is a process of major importance in forest dynamics. Although virgin and old-growth European\\u000a beech (Fagus sylvatica L.) forests in Europe have been studied for many years, there are to date no studies of individual-tree crown plasticity\\u000a and the way this is influenced by local neighborhood interactions in these forests. In this study, we analyzed crown

Matthias Schröter; Werner Härdtle; Goddert von Oheimb

2012-01-01

74

The influence of microclimate and tree age on the defense capacityof European beech ( Fagus sylvatica L.) against oxidative stress  

Microsoft Academic Search

Microclimate and tree age have been suggested to be factors influencing the defense capacity against oxidative stress. Therefore, 5-year-old Fagus sylvatica seedlings were grown on a scaffolding in the sun and shade crown of 55-year-old trees throughout one growing season. Independent of tree age sun leaves had a lower specific leaf area, lower pigment contents and a more capacitive antioxidative

Gerhard Wieser; Karin Hecke; Michael Tausz; Thorsten E. E. Grams; Rainer Matyssek

2003-01-01

75

Development and characterization of recombinant chromosome substitution lines (RCSLs) using Hordeum vulgare subsp. spontaneum as a source of donor alleles in a Hordeum vulgare subsp. vulgare background  

Microsoft Academic Search

The ancestor of barley (Hordeum vulgare subsp. spontaneum) may be a source of novel alleles for crop im- provement. We developed a set of recombinant chromosome substitution lines (RCSLs) using an accession of H. vulgare subsp. spontaneum (Caesarea 26-24, from Israel) as the donor and Hordeum vulgare subsp. vulgare 'Har- rington' (the North American malting quality standard) as the recurrent

I. Matus; A. Corey; T. Filichkin; P. M. Hayes; M. I. Vales; J. Kling; O. Riera-Lizarazu; K. Sato; W. Powell; R. Waugh

2003-01-01

76

A low G+C content genetic island in Mycobacterium avium subsp. paratuberculosis and M. avium subsp. silvaticum with homologous genes in Mycobacterium tuberculosis  

Microsoft Academic Search

The technique of representation difference analysis PCR has been applied to find genes specific to Mycobacterium avium subsp. paratuberculosis. This generated a 671 bp fragment which was used to isolate a larger genetic element found in the enteric pathogens M. avium subsp. paratuberculosis and M. avium subsp. silvaticum but which was absent from the very closely related and relatively benign

Mark Tizard; Tim Bull; Douglas Millar; Tim Doran; Helene Martin; Nazira Sumar; Jon Ford; John Hermon-Taylor

1998-01-01

77

A pyrosequencing insight into sprawling bacterial diversity and community dynamics in decaying deadwood logs of Fagus sylvatica and Picea abies.  

PubMed

Deadwood is an important biodiversity hotspot in forest ecosystems. While saproxylic insects and wood-inhabiting fungi have been studied extensively, little is known about deadwood-inhabiting bacteria. The study we present is among the first to compare bacterial diversity and community structure of deadwood under field conditions. We therefore compared deadwood logs of two temperate forest tree species Fagus sylvatica and Picea abies using 16S rDNA pyrosequencing to identify changes in bacterial diversity and community structure at different stages of decay in forest plots under different management regimes. Alphaproteobacteria, Acidobacteria and Actinobacteria were the dominant taxonomic groups in both tree species. There were no differences in bacterial OTU richness between deadwood of Fagus sylvatica and Picea abies. Bacteria from the order Rhizobiales became more abundant during the intermediate and advanced stages of decay, accounting for up to 25% of the entire bacterial community in such logs. The most dominant OTU was taxonomically assigned to the genus Methylovirgula, which was recently described in a woodblock experiment of Fagus sylvatica. Besides tree species we were able to demonstrate that deadwood physico-chemical properties, in particular remaining mass, relative wood moisture, pH, and C/N ratio serve as drivers of community composition of deadwood-inhabiting bacteria. PMID:25851097

Hoppe, Björn; Krger, Krüger; Kahl, Tiemo; Arnstadt, Tobias; Buscot, François; Bauhus, Jürgen; Wubet, Tesfaye

2015-01-01

78

A pyrosequencing insight into sprawling bacterial diversity and community dynamics in decaying deadwood logs of Fagus sylvatica and Picea abies  

PubMed Central

Deadwood is an important biodiversity hotspot in forest ecosystems. While saproxylic insects and wood-inhabiting fungi have been studied extensively, little is known about deadwood-inhabiting bacteria. The study we present is among the first to compare bacterial diversity and community structure of deadwood under field conditions. We therefore compared deadwood logs of two temperate forest tree species Fagus sylvatica and Picea abies using 16S rDNA pyrosequencing to identify changes in bacterial diversity and community structure at different stages of decay in forest plots under different management regimes. Alphaproteobacteria, Acidobacteria and Actinobacteria were the dominant taxonomic groups in both tree species. There were no differences in bacterial OTU richness between deadwood of Fagus sylvatica and Picea abies. Bacteria from the order Rhizobiales became more abundant during the intermediate and advanced stages of decay, accounting for up to 25% of the entire bacterial community in such logs. The most dominant OTU was taxonomically assigned to the genus Methylovirgula, which was recently described in a woodblock experiment of Fagus sylvatica. Besides tree species we were able to demonstrate that deadwood physico-chemical properties, in particular remaining mass, relative wood moisture, pH, and C/N ratio serve as drivers of community composition of deadwood-inhabiting bacteria. PMID:25851097

Hoppe, Björn; Krger, Krüger; Kahl, Tiemo; Arnstadt, Tobias; Buscot, François; Bauhus, Jürgen; Wubet, Tesfaye

2015-01-01

79

Streptococcus dysgalactiae subsp. equisimilis bacteremia: an emerging infection.  

PubMed

The importance of group C and G Streptococcus dysgalactiae subspecies equisimilis (S. dysgalactiae subsp. equisimilis) as a significant pathogen has recently been better recognized. S. dysgalactiae subsp. equisimilis disease can range in severity from milder skin and soft-tissue conditions such as wound infection, erysipelas, and cellulitis, to life-threatening necrotizing fasciitis and streptococcal toxic shock syndrome, thus sharing the clinical picture with S. pyogenes. The most common clinical manifestation of bacteremia is cellulitis. An increase in the incidence of S. dysgalactiae subsp. equisimilis bacteremia has been recognized. Invasive forms of this infection are most commonly found in elderly patients with underlying comorbidities and skin breakdown. The case fatality in bacteremia has been reported to be 15-18%. In this review, the epidemiology, clinical characteristics, and emm types of S. dysgalactiae subsp. equisimilis bacteremia are summarized. PMID:24682845

Rantala, S

2014-08-01

80

Branch enclosure BVOC flux measurements from Fagus sylvatica L. in a natural forest environment: preliminary results  

NASA Astrophysics Data System (ADS)

Natural ecosystems, such as forests, are known to be important sources of non-methane volatile organic compounds (NMVOCs). Oxidation of these biogenic VOCs (BVOCs) in the presence of nitrogen oxides can result in net ozone formation and the low-volatility oxidation products may contribute to secondary organic aerosol formation and/or growth. As a result BVOC emissions can have a negative effect on air quality and human health. In the commonly used emission algorithms [Guenther et al., 1995], leaf temperature and photosynthetic photon flux density (PPFD) are the driving variables for BVOC emissions. However, in order to better explain the variability over time of BVOC emissions for a given tree species, the most recent emission algorithms, such as MEGAN [Guenther et al., 2006], also consider other driving variables such as phenology, temperature and light history. To validate these new emission algorithms, dynamic branch enclosure BVOC flux measurements have been performed on an adult Fagus sylvatica L. tree in a natural forest environment under ambient PPFD and temperature conditions. Branches at different levels in the canopy were accessible from a 35 m high measurement tower. The cuvette air was analysed on-line with a hs-PTR-MS instrument, which was located in a log cabin at the bottom of the tower. Ion signals related to monoterpenoid compounds (m/z 81 and 137), isoprene (m/z 69), acetone (m/z 59) and methanol (m/z 33) have been measured continuously with the PTR-MS during several phenological periods, from bud-break to senescence. The data show high monoterpenoid emission rates in spring which gradually decrease until leaf fall. Furthermore, monoterpenoid emissions from shaded leaves in the lower layers of the canopy were found to be negligible compared to those from sunlit leaves in the upper layer of the canopy. Effects of light and temperature history on monoterpenoid emissions from Fagus sylvatica L. will be discussed and compared with results obtained in a growth room under controlled conditions of light and temperature. Guenther et al., J. Geophys. Res. 100 (1995) 8873-8892. Guenther et al., Atm. Chem. Phys. 6 (2006) 3181-3210. The authors gratefully acknowledge the support from the Belgian Science Policy through the Program "Science for a Sustainable Development: Terrestrial Ecology" (contract # SD/TE/03A) and from the "Fonds Wetenschappelijk Onderzoek - Vlaanderen" (contract # G.0031.07).

Demarcke, M.; Amelynck, C.; Schoon, N.; Müller, J.-F.; Joo, E.; Dewulf, J.; van Langenhove, H.; Šimpraga, M.; Steppe, K.; Lemeur, R.; Samson, R.

2009-04-01

81

Real-time PCR for detection and differentiation of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus  

Microsoft Academic Search

Strangles is a contagious equine disease caused by Streptococcus equi subsp. equi. In this study, clinical strains of S. equi (n=24) and Streptococcus equi subsp. zooepidemicus (n=24) were genetically characterized by sequencing of the 16S rRNA and sodA genes in order to devise a real-time PCR system that can detect S. equi and S. zooepidemicus and distinguish between them.Sequencing demonstrated

V. Båverud; S. K. Johansson; A. Aspan

2007-01-01

82

Geographic distribution of chloroplast variation in Italian populations of beech (Fagus sylvatica L.).  

PubMed

The distribution of chloroplast DNA (cpDNA) variation in Italian beech ( Fagus sylvatica L.) populations was studied using PCR-RFLP and microsatellite markers. In total, 67 populations were analysed, and 14 haplotypes were identified by combining the two marker types. A remarkable subdivision of cpDNA diversity in Italian beech was found, as indicated by a high level of genetic differentiation ( G(st)=0.855). The highest level of total haplotype diversity ( h(t)=0.822) was estimated for southern Italian populations. The highest number of haplotypes was found in the central-southern region of the peninsula. The nested clade analysis provided evidence for past fragmentation events that may have been occurred during the Quaternary glaciations and had a major role in defining the genetic structure of the central-southern Italian beech populations. Only one haplotype apparently spread towards the north of Italy along the Apennine chain and reached the Italian slope of the western part of the Alps (Maritime Alps, Liguria). All haplotypes found along the Apennines remained trapped in the Italian peninsula. Southern and central Italy represent hotspots of haplotype diversity for Italian beech. PMID:15014873

Vettori, C; Vendramin, G G; Anzidei, M; Pastorelli, R; Paffetti, D; Giannini, R

2004-06-01

83

Insights into xylem vulnerability to cavitation in Fagus sylvatica L.: phenotypic and environmental sources of variability.  

PubMed

Xylem vulnerability to cavitation is a key parameter in understanding drought resistance of trees. We determined the xylem water pressure causing 50% loss of hydraulic conductivity (P(50)), a proxy of vulnerability to cavitation, and we evaluated the variability of this trait at tree and population levels for Fagus sylvatica. We checked for the effects of light on vulnerability to cavitation of stem segments together with a time series variation of P(50). Full sunlight-exposed stem segments were less vulnerable to cavitation than shade-exposed ones. We found no clear seasonal change of P(50), suggesting that this trait was designed for a restricted period. P(50) varied for populations settled along a latitudinal gradient, but not for those sampled along an altitudinal gradient. Moreover, mountainside exposure seemed to play a major role in the vulnerability to cavitation of beech populations, as we observed the differences along north-facing sides but not on south-facing sides. Unexpectedly, both north-facing mountainside and northern populations appeared less vulnerable than those grown on the southern mountainside or in the South of France. These results on beech populations were discussed with respect to the results at within-tree level. PMID:20935319

Herbette, Stephane; Wortemann, Remi; Awad, Hosam; Huc, Roland; Cochard, Herve; Barigah, Tete Severien

2010-11-01

84

Phenols in leaves and bark of Fagus sylvatica as determinants of insect occurrences.  

PubMed

Beech forests play an important role in temperate and north Mediterranean ecosystems in Greece since they occupy infertile montane soils. In the last glacial maximum, Fagus sylvatica (beech) was confined to Southern Europe where it was dominant and in the last thousand years has expanded its range to dominate central Europe. We sampled four different beech forest types. We found 298 insect species associated with beech trees and dead beech wood. While F. sylvatica and Quercus (oak) are confamilial, there are great differences in richness of the associated entomofauna. Insect species that inhabit beech forests are less than one fifth of those species living in oak dominated forests despite the fact that beech is the most abundant central and north European tree. There is a distinct paucity of monophagous species on beech trees and most insect species are shared between co-occurring deciduous tree species and beech. This lack of species is attributed to the vegetation history and secondary plant chemistry. Bark and leaf biophenols from beech indicate that differences in plant secondary metabolites may be responsible for the differences in the richness of entomofauna in communities dominated by beech and other deciduous trees. PMID:21686149

Petrakis, Panos V; Spanos, Kostas; Feest, Alan; Daskalakou, Evangelia

2011-01-01

85

Variation in throughfall deposition across a deciduous beech (Fagus sylvatica L.) forest edge in Flanders.  

PubMed

Throughfall deposition and canopy exchange of acidifying and eutrophying compounds and major base cations were studied by means of throughfall analysis in a deciduous beech (Fagus sylvatica L.) forest edge in Belgium over a period of 1 year. Throughfall fluxes of Cl(-), NH(4)(+) and Na(+) were significantly elevated at the forest edge compared to the forest interior. As no edge effect on throughfall water volume could be detected, the observed edge enhancement effects were mainly due to dry deposition and canopy exchange patterns. Indeed, there was an elevated dry deposition of Cl(-), Na(+), K(+), Ca(2+) and Mg(2+) up to 50 m from the field/forest border. Within the forest, throughfall and dry deposition of SO(4)(2-) were highly variable and no significant differences were observed between the forest edge and the forest interior. Leaching of K(+) and Ca(2+) was reduced in the forest edge up to a distance of 30 m from the border. The measured nitrogen and acidic depositions far exceeded the current Flemish critical loads with respect to the protection of biodiversity in forests, especially at the forest edge. This points to an urgent need for controlling emissions as well as the need to consider the elevated deposition load in forest edges when calculating the critical loads in forests. PMID:15626394

Devlaeminck, Rebecca; De Schrijver, An; Hermy, Martin

2005-01-20

86

Variation in biogenic volatile organic compound emission pattern of Fagus sylvatica L. due to aphid infection  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) have been the focus of interest to understand atmospheric processes and their consequences in formation of ozone or aerosol particles; therefore, VOCs contribute to climate change. In this study, biogenic VOCs (BVOCs) emitted from Fagus sylvatica L. trees were measured in a dynamic enclosure system. In total 18 compounds were identified: 11 monoterpenes (MT), an oxygenated MT, a homoterpene (C 14H 18), 3 sesquiterpenes (SQT), isoprene and methyl salicylate. The frequency distribution of the compounds was tested to determine a relation with the presence of the aphid Phyllaphis fagi L. It was found that linalool, (E)-?-ocimene, ?-farnesene and a homoterpene identified as (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), were present in significantly more samples when infection was present on the trees. The observed emission spectrum from F. sylvatica L. shifted from MT to linalool, ?-farnesene, (E)-?-ocimene and DMNT due to the aphid infection. Sabinene was quantitatively the most prevalent compound in both, non-infected and infected samples. In the presence of aphids ?-farnesene and linalool became the second and third most important BVOC emitted. According to our investigation, the emission fingerprint is expected to be more complex than commonly presumed.

Joó, É.; Van Langenhove, H.; Šimpraga, M.; Steppe, K.; Amelynck, C.; Schoon, N.; Müller, J.-F.; Dewulf, J.

2010-01-01

87

The chromosome morphology of Hesperis matronalis subsp. matronalis and related diploid taxa  

Microsoft Academic Search

Hesperis matronalis L. subsp.matronalis contains various genoms having the same chromosome number (2n=24), differing, however, by ther-index of some pairs of homologous chromosomes. Diploid sets of the taxaHesperis matronalis L. subsp.matronalis, Hesperis sylvestris\\u000a Crantz subsp.sylvestris, Hesperis sylvestris\\u000a Crantz subsp.velenovskyi\\u000a (Fritsch) Borza andHesperis steveniana DC. are compared.

František Dvo?ák; Božena Dadáková

1976-01-01

88

Sugar Utilization and Acid Production by Free and Entrapped Cells of Streptococcus salivarius subsp. thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Lactococcus lactis subsp. lactis in a Whey Permeate Medium  

PubMed Central

Cells of Streptococcus salivarius subsp. thermophilus and Lactococcus lactis subsp. lactis entrapped in k-carrageenan-locust bean gum gel performed similarly to free cells in the conversion of lactose to lactic acid. Bead diameter influenced the fermentation rate. Cells entrapped in smaller beads (0.5 to 1.0 mm) showed higher release rates, higher lactose, glucose, and formic acid utilization, higher galactose accumulation, and higher lactic acid production than did cells entrapped in larger beads (1.0 to 2.0 mm). Values for smaller beads were comparable with those for free cells. Immobilization affected the fermentation rate of lactic acid bacteria, especially Lactobacillus delbrueckii subsp. bulgaricus. Entrapped cells of L. delbrueckii subsp. bulgaricus demonstrated a lower lactic acid production than did free cells in batch fermentation. The kinetics of the production of formic and pyruvic acids by L. lactis subsp. lactis and S. salivarius subsp. thermophilus are presented. PMID:16347822

Audet, Pascal; Paquin, Celine; Lacroix, Christophe

1989-01-01

89

Bartonella vinsonii subsp. berkhoffii in free-ranging white-tailed deer (Odocoileus virginianus).  

PubMed

Bartonella vinsonii subsp. berkhoffii has not been detected previously in white-tailed deer (Odocoileus virginianus). We tested whole blood from 60 white-tailed deer for Bartonella spp. DNA; three (5%) were positive for Bartonella vinsonii subsp. berkhoffii. This is the first detection of Bartonella vinsonii subsp. berkhoffii in white-tailed deer. PMID:23568932

Chitwood, M Colter; Maggi, Ricardo G; Kennedy-Stoskopf, Suzanne; Toliver, Marcée; DePerno, Christopher S

2013-04-01

90

Growth and posture control strategies in Fagus sylvatica and Acer pseudoplatanus saplings in response to canopy disturbance  

PubMed Central

Background and Aims Forest tree saplings that grow in the understorey undergo frequent changes in their light environment to which they must adapt to ensure their survival and growth. Crown architecture, which plays a critical role in light capture and mechanical stability, is a major component of sapling adaptation to canopy disturbance. Shade-adapted saplings typically have plagiotropic stems and branches. After canopy opening, they need to develop more erect shoots in order to exploit the new light conditions. The objective of this study was to test whether changes in sapling stem inclination occur after canopy opening, and to analyse the morphological changes associated with stem reorientation. Methods A 4-year canopy-opening field experiment with naturally regenerated Fagus sylvatica and Acer pseudoplatanus saplings was conducted. The appearance of new stem axes, stem basal diameter and inclination along the stem were recorded every year after canopy opening. Key Results Both species showed considerable stem reorientation resulting primarily from uprighting (more erect) shoot movements in Fagus, and from uprighting movements, shoot elongation and formation of relay shoots in Acer. In both species, the magnitude of shoot uprighting movements was primarily related to initial stem inclination. Both the basal part and the apical part of the stem contributed to uprighting movements. Stem movements did not appear to be limited by stem size or by stem growth. Conclusions Stem uprighting movements in shade-adapted Fagus and Acer saplings following canopy disturbance were considerable and rapid, suggesting that stem reorientation processes play a significant role in the growth strategy of the species. PMID:21444338

Collet, Catherine; Fournier, Mériem; Ningre, François; Hounzandji, Ablo Paul-Igor; Constant, Thiéry

2011-01-01

91

Does mixing of beech (Fagus sylvatica) and spruce (Picea abies) litter hasten decomposition?  

PubMed Central

Background and aims It is of practical relevance to know how much beech must be admixed to pure spruce stands in order to increase litter decomposition and associated nutrient cycling, since the formation of thick organic layers is commonly ascribed to the recalcitrance of spruce needles. We addressed the impact of tree species mixture within forest stands and within litter on mass loss and nutritional release from litter. Methods Litter decomposition was measured in three adjacent stands of pure spruce (Picea abies), mixed beech-spruce and pure beech (Fagus sylvatica) on a nutrient-rich site and a nutrient-poor site over a 2-year period using litterbags which were filled with five different mixtures of beech and spruce litter. Results Mass loss of beech litter was not higher than mass loss of spruce litter. Decay was primarily affected by tree species composition of the incubation stand and was faster in (mixed) beech forests stands than in spruce forests, while the influence of litter species and their mixtures on decay rates was small. Net transfers of nutrients between the two litter species (direct effects) in the mixed bags were minimal, since initial beech and spruce litter did not have different litter quality. However, in a few cases indirect effects (e.g., changing decomposer abundance and activity) caused non-additive patterns for the totals within the mixed bags, hastening decomposition within the first year. Conclusions Greater accumulation of litter in spruce compared to beech stands is not a consequence of the inherent recalcitrance of needles. Adverse environmental conditions in spruce stands retard decomposition. Indirect effects on decomposition caused by stand mixture are not mimicked by litter mixtures within mesh bags. PMID:24744450

Berger, Torsten W.; Berger, Pétra

2014-01-01

92

Clear link between drought stress, photosynthesis and biogenic volatile organic compounds in Fagus sylvatica L.  

NASA Astrophysics Data System (ADS)

Direct plant stress sensing is the key for a quantitative understanding of drought stress effects on biogenic volatile organic compound (BVOC) emissions. A given level of drought stress might have a fundamentally different effect on the BVOC emissions of different plants. For the first time, we continuously quantified the level of drought stress in a young potted beech ( Fagus sylvatica L.) with a linear variable displacement transducer (LVDT) installed at stem level in combination with simultaneous measurements of BVOC emissions and photosynthesis rates at leaf level. This continuous set of measurements allowed us to examine how beech alters its pattern of photosynthesis and carbon allocation to BVOC emissions (mainly monoterpenes, MTs) and radial stem growth during the development of drought stress. We observed an increasing-decreasing trend in the MT emissions as well as in the fraction of assimilated carbon re-emitted back into the atmosphere (ranging between 0.14 and 0.01%). We were able to link these dynamics to pronounced changes in radial stem growth, which served as a direct plant stress indicator. Interestingly, we detected a sudden burst in emission of a non-identified, non-MT BVOC species when drought stress was acute (i.e. pronounced negative stem growth). This burst might have been caused by a certain stress-related green leaf volatile, which disappeared immediately upon re-watering and thus the alleviation of drought stress. These results highlight that direct plant stress sensing creates opportunities to understand the overall complexity of stress-related BVOC emissions.

Šimpraga, M.; Verbeeck, H.; Demarcke, M.; Joó, É.; Pokorska, O.; Amelynck, C.; Schoon, N.; Dewulf, J.; Van Langenhove, H.; Heinesch, B.; Aubinet, M.; Laffineur, Q.; Müller, J.-F.; Steppe, K.

2011-09-01

93

Germination and Initial Growth of Fagus orientalis Seedling under Different Stand Canopies  

NASA Astrophysics Data System (ADS)

Germination and early growth of Fagus orientalis seedling were studied in four stands with different canopy closures (closed, semi-closed, relatively-opened and opened stands) under a dominant beech forest, located in north of Iran. For this purpose, 196 beech seed-sown plastic pots (in four plots of 49 units) were set up under each canopy closure. In the beginning of the first growing season germination rate ranged between 78.1 and 84.7% in different stands but there was no statistically significant difference of this term in the stands. In the end of the first growing season survival rate of seedlings was 73.9-76.1% under closed and semi-closed stands. It decreased significantly to 31.7 and 18.0% under relatively-opened and opened stands, respectively. Shoot length was, in the order 70 and 90 mm in closed and semi-closed stands. It decreased to 40 and 30 mm in relatively-opened and opened stands, respectively. Vitality appeared mostly with high quality in closed and semi-closed stands and with low quality in relatively-opened and opened stands. Leaf biomass reduced in closed stand. There was an increase for leaf area in semi-closed stand and for Specific Leaf Weight (SLW) in relatively-opened and opened stands. Generally, the investigation shows that in the first growing season most characteristics of beech seedling were benefited from more favorable conditions in the denser stands (closed and semi-closed canopies).

Tabari, Masoud

94

Photoinhibition in seedlings of Fraxinus and Fagus under natural light conditions: implications for forest regeneration?  

PubMed

Ash (Fraxinus excelsior L.) and beech (Fagus sylvatica L.) seedlings were grown in the field under three levels of natural light: (1) open, (2) gap and (3) shade. Light acclimation of photosynthesis was characterized by means of modulated chlorophyll a fluorescence of intact leaves and growth parameters were measured at the end of the growing season. Measurements of maximum photochemical efficiency (Fv/Fm) of dark-adapted leaves at intervals through the day showed that ash had a higher Fv/Fm than beech in open and gap plots but not in shade plots. This indicated a larger build-up of photoinhibition in beech under gap and open conditions. Steady-state light response curves of the operating efficiency of PSII (F'q/F'm), the electron transport rate (ETR) and the photochemical efficiency factor (F'q/F'v) showed greater variability across light treatments in ash than in beech. Both species exhibited similar responses of non-photochemical quenching (NPQ) to light. When the data were normalized to the mean maximum irradiance in the growth environment, all photochemical parameters showed a reduction in variation across treatments, indicating that light acclimation in the two species occurred primarily through adjustments in rates of photochemistry. Adjustments in thermal heat dissipation were small in both species. This pattern was stronger in ash, suggesting a greater degree of phenotypic plasticity in photosynthetic capacity in this earlier successional species. Contrary to our expectations, the build-up of photoinhibition in beech did not appear to have a negative effect on total biomass accumulation relative to ash. PMID:15150656

Einhorn, Katrina S; Rosenqvist, Eva; Leverenz, Jerry W

2004-07-01

95

Differences in beech ( Fagus crenata ) regeneration between two types of Japanese beech forest and along a snow gradient  

Microsoft Academic Search

Differences in beech (Fagus\\u000a crenata) regeneration were quantitatively investigated using power function analysis for the size–class (diameter at breast height, DBH) distribution and juvenile-to-canopy tree (J\\/C) ratio along a snow gradient throughout Japan. In snowy areas, all species combined, as well as F. crenata alone, showed constant regeneration, with parameter b??1.6 for the power function y=ax\\u000a \\u000a b\\u000a (x=DBH, y=density), which

Koji Shimano

2006-01-01

96

Campylobacter fetus subsp. jejuni in a turkey processing plant.  

PubMed Central

Cecal cultures taken over a 1-year period from 600 turkeys at a poultry processing plant were all positive for Campylobacter fetus subsp. jejuni. Swabs of the cloaca and fresh feces were likewise all positive. Of 33 freshly dressed turkey carcases, 94% were positive before chilling in tanks of chlorinated ice and water; 34% of 83 carcasses were still positive after overnight soaking in the tanks. Increasing the chlorine content from 50 to 340 ppm (50 to 340 micrograms/ml) did not cause a decrease in the number of positive carcasses. C. fetus subsp. jejuni was isolated from wastewater gutters as well as from chutes and conveyor belts in the packaging room. Water samples from the five water treatment lagoons for the plant were all positive for C. fetus subsp. jejuni while the plant was in operation, but 4 days after the plant closed for the winter, all water samples were negative. PMID:7204547

Luechtefeld, N W; Wang, W L

1981-01-01

97

Isolation of Campylobacter fetus subsp. jejuni from migratory waterfowl.  

PubMed Central

Since the sources from which humans acquire Campylobacter enteritis are only partially known, we studied the frequency of carriage of Campylobacter fetus subsp. jejuni in migratory waterfowl. Cecal contents of various species of wild ducks were cultured on selective media that contained antibiotics to inhibit normal flora. Thirty-five percent of the 445 ducks cultured harbored C. fetus subsp. jejuni. Migratory waterfowl are yet another reservoir for this enteric pathogen and may be of public health importance for humans in the contamination of water or when used as food. PMID:7217334

Luechtefeld, N A; Blaser, M J; Reller, L B; Wang, W L

1980-01-01

98

Toxicity and trichothecene production by Fusarium acuminatum subsp. acuminatum and Fusarium acuminatum subsp. armeniacum.  

PubMed

The toxicity of cultures of Fusarium acuminatum subsp. acuminatum and Fusarium acuminatum subsp. armeniacum grown on Weet-Bix medium was assessed using a chick bioassay. Thirty-nine of 45 cultures of F. a. armeniacum tested produced at least 50% mortality in the chick bioassay. In contrast, of the 26 cultures of F. a. acuminatum tested, only nine produced at least 50% mortality. Selected extracts of both subspecies were analyzed by gas chromatography after clean-up and hydrolysis for the four main trichothecene families, namely; nivalenol (NIV), deoxynivalenol (DON), scirpentriol (Sctol), and T-2 tetraol (T-2tol). Levels of up to 500 micrograms/g and 7 micrograms/g of T-2tol were detected in F. a. armeniacum and F. a. acuminatum extracts respectively. Four cultures each of F. a. armeniacum and F. a. acuminatum were also grown on two solid media (Weet-Bix and Vermiculite) and two liquid media (MYRO and GYEP). Culture extracts were again tested for toxicity and analyzed for trichothecene production. Cultures of F. a. armeniacum grown on the solid media and on MYRO produced the highest toxicity. Levels of up to 168, 129, 150, and 8 micrograms/g of T-2tol were detected in cultures of F. a. armeniacum on Weet-Bix, Vermiculite, MYRO, and GYEP respectively. In contrast, only trace amounts of T-2tol were detected in extracts of F. a. acuminatum on all media. Sctol levels of less than 0.5 microgram/g were also detected in some cultures of both subspecies on solid media, but only F. a. armeniacum produced trace levels of Sctol on liquid media.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8167939

Wing, N; Lauren, D R; Bryden, W L; Burgess, L W

1993-01-01

99

Assessing the impact of feral hog populations on the natural resources of Big Thicket National Preserve  

E-print Network

red oak (Q. falcata), sweetgum (Liquidambar styraciflua), American beech (Fagus grandifolia), and southern magnolia (M. grandiflora). Understories of slopes may include Flowering dogwood (Cornus florida), red maple (Acer rubrum), and American holly...

Chavarria, Pedro Mazier

2009-05-15

100

Mycobacterium avium subsp. paratuberculosis infection, immunology and pathology of livestock  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (MAP) infection in ruminants leads to a chronic and progressive enteric disease (Johne’s disease) that results in loss of intestinal function, poor body condition, and eventual death. Transmission is primarily through a fecal-oral route in neonates but con...

101

TARGETING MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS IN THE ENVIRONMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Diagnosis of Johne’s disease, an enteric infection of cattle caused by Mycobacterium avium subsp. paratuberculosis (MAP), has been impeded by the lack of rapid, reliable detection methods. The goal of this study was to optimize detection of MAP in environmental samples. Experiments were conducted to...

102

DETECTION OF MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS (MAP) IN THE ENVIRONMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne’s disease, a chronic, enteric infection that is passed from adults to calves via the fecal-oral route. MAP has become the focus of unwanted attention due to its increased prevalence and the economic impact resulting f...

103

Streptococcus equi subsp. zooepidemicus Infections Associated with Guinea Pigs  

PubMed Central

Streptococcus equi subsp. zooepidemicus is a known zoonotic pathogen. In this public health investigation conducted in Virginia, USA, in 2013, we identified a probable family cluster of S. zooepidemicus cases linked epidemiologically and genetically to infected guinea pigs. S. zooepidemicus infections should be considered in patients who have severe clinical illness and report guinea pig exposure. PMID:25531424

Young, Andrea; Levine, Seth J.; Garvin, Joseph P.; Brown, Susan; Turner, Lauren; Fritzinger, Angela; Gertz, Robert E.; Murphy, Julia M.; Vogt, Marshall; Beall, Bernard

2015-01-01

104

Global detection and identification of Campylobacter fetus subsp. venerealis  

Microsoft Academic Search

Bovine genital campylobacteriosis caused by Campylobacter fetus subsp. venerealis (Cfv) is a genital infection that threatens the cattle industry. Detection and identification of Cfv are key factors in control programmes. Trade regulations should be based on scientifically and internationally accepted methods of detection and identification of Cfv. Such methods are described in the World Health (OIE) Manual of Diagnostic Tests

Bergen van M. A. P; S. Linnane; Putten van J. P; J. A. Wagenaar

2005-01-01

105

Complete genome sequence of Clavibacter michiganensis subsp. insidiosus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Clavibacter michiganensis subsp. insidiosus (Cmi) causes bacterial wilt disease of alfalfa (Medicago sativa L.) and can also infect the model legume plant M. truncatula. The virulence mechanisms of Cmi are yet to be identified, hampered by the lack of efficient mutagenesis tools as well as by the la...

106

Staphylococcus aureus subsp. anaerobius strain ST1464 genome sequence  

PubMed Central

Staphylococcus aureus subsp. anaerobius is responsible for Morel's disease in animals and a cause of abscess in humans. It is characterized by a microaerophilic growth, contrary to the other strains of S. aureus. The 2,604,446-bp genome (32.7% GC content) of S. anaerobius ST1464 comprises one chromosome and no plasmids. The chromosome contains 2,660 open reading frames (ORFs), 49 tRNAs and three complete rRNAs, forming one complete operon. The size of ORFs ranges between 100 to 4,600 bp except for two ORFs of 6,417 and 7,173 bp encoding segregation ATPase and non-ribosomal peptide synthase, respectively. The chromosome harbors Staphylococcus phage 2638A genome and incomplete Staphylococcus phage genome PT1028, but no detectable CRISPRS. The antibiotic resistance gene for tetracycline was found although Staphylococcus aureus subsp. anaerobius is susceptible to tetracycline in-vitro. Intact oxygen detoxification genes encode superoxide dismutase and cytochrome quinol oxidase whereas the catalase gene is impaired by a stop codon. Based on the genome, in-silico multilocus sequence typing indicates that S. aureus subsp. anaerobius emerged as a clone separated from all other S. aureus strains, illustrating host-adaptation linked to missing functions. Availability of S. aureus subsp. anaerobius genome could prompt the development of post-genomic tools for its rapid discrimination from S. aureus. PMID:24501641

Elbir, Haitham; Robert, Catherine; Nguyen, Ti Thien; Gimenez, Grégory; El Sanousi, Sulieman M.; Flock, Jan-Ingmar; Raoult, Didier

2013-01-01

107

Novel cyanide-hydrolyzing enzyme from Alcaligenes xylosoxidans subsp. denitrificans  

SciTech Connect

A cyanide-metabolizing bacterium, strain DF3, isolated from soil was identified as Alcaligenes xylosoxidans subsp. denitrificans. Whole cells and cell extracts of strain DF3 catalyzed hydrolysis of cyanide to formate and ammonia (HCN + 2H{sub 2}O {r arrow} HCOOH + NH{sub 3}) without forming formamide as a free intermediate. The cyanide-hydrolyzing activity was inducibly produced in cells during growth in cyanide-containing media. Cyanate (OCN{sup {minus}}) and a wide range of aliphatic and aromatic nitriles were not hydrolyzed by intact cells of A. xylosoxidans subsp. denitrificans DF3. Strain DF3 hydrolyzed cyanide with great efficacy. Thus, by using resting induced cells at a concentration of 11.3 mg (dry weight) per ml, the cyanide concentration could be reduced from 0.97 M (approximately 25,220 ppm) to less than 77 nM (approximately 0.002 ppm) in 55 h. Enzyme purification established that cyanide hydrolysis by A. xylosoxidans subsp. denitrificans DF3 was due to a single intracellular enzyme. The molecular mass of the active enzyme (purity, {gt}97% as determined by amino acid sequencing) was estimated to be {gt}300,000 Da. The cyanide-hydrolyzing enzyme of A. xylosoxidans subsp. denitrificans DF3 was tentatively named cyanidase to distinguish it from known nitrilases (EC 3.5.5.1) which act on organic nitriles.

Ingvorsen, K.; Hojer-Pederson, B.; Godtfredsen, S.E. (Novo Nordisk A/S, Bagsvaerd (Denmark))

1991-06-01

108

Complete Genome Sequence of Anaplasma marginale subsp. centrale  

Technology Transfer Automated Retrieval System (TEKTRAN)

Anaplasma marginale subsp. centrale is a naturally attenuated subtype that has been used as a vaccine for a century. We sequenced the genome of this organism and compared it to those of virulent senso stricto A. marginale strains. The comparison markedly narrows the number of outer membrane protein ...

109

Heat Inactivation of Mycobacterium avium subsp. paratuberculosis in Milk  

Microsoft Academic Search

The effectiveness of pasteurization and the concentration of Mycobacterium avium subsp. paratuberculosis in raw milk have been identified in quantitative risk analysis as the most critical factors influencing the potential presence of viable Mycobacterium paratuberculosis in dairy products. A quantitative assessment of the lethality of pasteurization was undertaken using an industrial pasteurizer designed for research purposes with a validated Reynolds

Wendy L. McDonald; Kimberly J. O'Riley; Christopher J. Schroen; Robin J. Condron

2005-01-01

110

Laminaria japonica Extract, an Inhibitor of Clavibater michiganense Subsp. Sepedonicum  

PubMed Central

Bacterial ring rot of potato is one of the most serious potato plant and tuber diseases. Laminaria japonica extract was investigated for its antimicrobial activity against Clavibater michiganense subsp. sepedonicum (Spieckermann & Kotthoff) Davis et al., the causative agent of bacterial ring rot of potato. The results showed that the optimum extraction conditions of antimicrobial substances from L. japonica were an extraction temperature of 80°C, an extraction time of 12 h, and a solid to liquid ratio of 1?25. Active compounds of L. japonica were isolated by solvent partition, thin layer chromatography (TLC) and column chromatography. All nineteen fractionations had antimicrobial activities against C. michiganense subsp. sepedonicum, while Fractionation three (Fr.3) had the highest (P<0.05) antimicrobial activity. Chemical composition analysis identified a total of 26 components in Fr.3. The main constituents of Fr.3 were alkanes (80.97%), esters (5.24%), acids (4.87%) and alcohols (2.21%). Antimicrobial activity of Fr.3 against C. michiganense subsp. sepedonicum could be attributed to its ability to damage the cell wall and cell membrane, induce the production of reactive oxygen species (ROS), increase cytosolic Ca2+ concentration, inhibit the glycolytic pathway (EMP) and tricarboxylic acid (TCA) cycle, inhibit protein and nucleic acid synthesis, and disrupt the normal cycle of DNA replication. These findings indicate that L. japonica extracts have potential for inhibiting C. michiganense subsp. sepedonicum. PMID:24714388

Cai, Jin; Feng, Jia; Xie, Shulian; Wang, Feipeng; Xu, Qiufeng

2014-01-01

111

Subandrodioecy and Male Fitness in Sagittaria lancifolia Subsp. Lancifolia (Alismataceae)  

Microsoft Academic Search

Sagittaria lancifolia subsp. lancifolia is described as cosexual (monoecious), but the study population consisted of 84% cosexuals that typically had 35% pistillate buds and 16% predominant males that typically had 0-2% pistillate buds. Hand- pollinations showed that pistillate flowers required pollination to set seed, and pollen from both male and cosexual plants was potent. No gender switching was seen in

Gayle E. Muenchow

1998-01-01

112

Growth Dynamics During Canopy Recruitment of Sprout-Origin Stems in Japanese Beech (Fagus japonicaMaxim.) Stools in Old Growth Forests of Central Japan  

Microsoft Academic Search

In order to clarify mechanisms of canopy recruitment of Fagus japonicastems of sprout origin, age structure and growth dynamics were studied for stems within beech stools in two stands of old growth forests on the Pacific side of central Japan. The DBH vs. height and age relationships of the beech stems showed continuous distribution from small-young, understory stems to large-old,

Tatsuhiro Ohkubo; Takeo Tanimoto; Rob Peters; Haruo Sawada; Mikio Kaji

1997-01-01

113

Significant light and temperature dependent monoterpene emissions from European beech (Fagus sylvatica L.) and their potential impact on the European volatile organic compound budget  

Microsoft Academic Search

By using a dynamic branch enclosure system the emission of monoterpenes from European beech (Fagus sylvatica L.) was investigated during two consecutive summer vegetation periods in the years of 2002 and 2003 in Germany. All measurements were performed under field conditions within the framework of the ECHO project (Emission and Chemical Transformation of Biogenic Volatile Organic Compounds, AFO 2000). European

T. Dindorf; U. Kuhn; L. Ganzeveld; G. Schebeske; P. Ciccioli; C. Holzke; R. Köble; G. Seufert; J. Kesselmeier

2006-01-01

114

Vulnerability of xylem to embolism in relation to leaf water potential and stomatal conductance in Fagus sylvatica f. purpurea and Populus balsamifera  

Microsoft Academic Search

The vulnerability of xylem vessels to water stress- induced cavitation was studied by measuring hydraulic conductivity and ultrasound acoustic emissions (AEs) in Fagus sylvatica L. f. purpurea (Ait.) Schneid. and Populus balsamifera L.. The occurrence of xylem embolism in summer was investigated in relation to leaf water potential and stomatal conductance. Populus was extremely vulnerable to cavitation, losing functional vessels

U. Hacke; J. J. Sauter

1995-01-01

115

Climate variation and the stable carbon isotope composition of tree ring cellulose: an intercomparison of Quercus robur, Fagus sylvatica and Pinus silvestris  

Microsoft Academic Search

The relationship between climate parameters and the carbon stable isotope composition (delta13C), of annual tree ring cellulose is examined for three native British tree species; Common beech (Fagus sylvatica L.), Pedunculate oak (Quercus robur L.) and Scots pine (Pinus sylvestris L.). The last 100 annual tree rings of six trees, two of each species, were cut into slivers and the

D. L. Hemming; V. R. Switsur; J. S. Waterhouse; T. H. E. Heaton; A. H. C. Carter

1998-01-01

116

Staphylococcus schleiferi subsp. coagulans subsp. nov. Isolated from the External Auditory Meatus of Dogs with External Ear Otitis  

Microsoft Academic Search

A new subspecies, Staphylococcus schleiferi subsp. couguluns, was isolated from the external auditory meatus of dogs suffering from external ear otitis and is described on the basis of studies of 21 strains. Phenotypic studies showed that these strains are more closely related to Staphylococcus intermedius than to other staphylococci, but DNA hybridization studies indicated that they are closely related to

SHIZUNOBU IGIMI; EIJI TAKAHASHI; TOMOTARI MITSUOKA

117

Amplified Fragment Length Polymorphism (AFLP) reveals no genetic divergence of the Eastern Alpine endemic Oxytropis campestris subsp. tiroliensis (Fabaceae) from widespread subsp. campestris  

Microsoft Academic Search

Applying Amplified Fragment Length Polymorphism, we explored genetic differences between widespread Oxytropis campestris subsp. campestris and O. campestris subsp. tiroliensis, a presumed glacial relict restricted to a small area along the main chain of the Eastern Alps. We could not find genetic differences between the two “taxa”. Neither do the morphological characters given in the literature discriminate between them. Therefore

Peter Schönswetter; Andreas Tribsch; Harald Niklfeld

2004-01-01

118

Taxonomic investigation of representatives of the genus Sphaerotilus: descriptions of Sphaerotilus montanus sp. nov., Sphaerotilus hippei sp. nov., Sphaerotilus natans subsp. natans subsp. nov. and Sphaerotilus natans subsp. sulfidivorans subsp. nov., and an emended description of the genus Sphaerotilus.  

PubMed

Seven strains of the genus Sphaerotilus were obtained from natural thermal sulfide (strains D-501(T), D-502, D-504, D-505 and D-507) and low-temperature ferrous (strain HS(T)) springs and from an activated sludge system (strain D-380). These Sphaerotilus isolates and strains of Sphaerotilus natans obtained from the DSMZ (S. natans DSM 6575(T), DSM 565 and DSM 566) were studied using a polyphasic taxonomic approach. All strains had Q-8 as the major quinone and C(16?:?1)?7, C(16?:?0) and C(18?:?1)?7 as the major fatty acids. The DNA-DNA hybridization results and 16S rRNA, hsp60 and gyrB gene sequencing experiments showed that isolates D-501(T), D-502, D-504, D-505, D-507 and D-380 were closely related to the type strain of S. natans DSM 6575(T). However, strains D-501(T), D-502, D-504, D-505 and D-507 significantly differed from the heterotrophic strain S. natans DSM 6575(T) by their capability for lithotrophic growth with reduced sulfur compounds as an electron donor for energy conservation and some other phenotypic features. For this reason, strains D-501(T), D-502, D-504, D-505 and D-507 merit a separate taxonomic classification at the subspecies level. The name Sphaerotilus natans subsp. sulfidivorans subsp. nov. (type strain D-501(T)?=?DSM 22545(T)?=?VKM B-2573(T)) is proposed. The subspecies Sphaerotilus natans subsp. natans subsp. nov. is automatically created as a result of this proposal. Strain D-380 was phenotypically closely related to S. natans DSM 6575(T). Strains D-380 and S. natans DSM 6575(T) were assigned to the subspecies Sphaerotilus natans subsp. natans subsp. nov. (type strain DSM 6575(T)?=?ATCC 13338(T)). The 16S rRNA, hsp60 and gyrB gene sequences obtained for strains HS(T) and DSM 565 showed very low sequence similarity values of 97.3?%, 89.7?% and 88.4?%, respectively, with S. natans DSM 6575(T). Strain HS(T) shared 99?% DNA-DNA relatedness with strain. PMID:20495027

Gridneva, Elena; Chernousova, Elena; Dubinina, Galina; Akimov, Vladimir; Kuever, Jan; Detkova, Ekaterina; Grabovich, Margarita

2011-04-01

119

Vertical differences in autumn phenology of Fagus sylvatica L. in a mixed forest, southern Germany  

NASA Astrophysics Data System (ADS)

Phenological variation among trees of different heights provides a small scale ecological distinction within the forest allowing the optimization of light interception and consequently net carbon gain. Several studies showed that juveniles and suppressed adult individuals can adopt a "phenological escape" strategy by leafing out earlier during spring or by delaying autumn phenology in relation to adult overstory trees. While spring phenological variations in temperate forests were well studied, for autumn phenology it is still unclear whether ontogenetic or microclimatic factors are more decisive. We regularly observed leaf coloring and leaf fall phenology of 166 European beech individuals (Fagus sylvatica L.; Fagaceae), during autumn 2012 in a mixed forest (Kranzberger Forst) in southern Germany and installed 18 loggers for measuring air temperature and humidity at different sites and heights. Our objectives were: (1) to identify microclimatic differences at our observation sites (2) to determine the extent of phenological variations between trees of different life stages (overstory, mesostory and understory); and (3) to examine whether phenology varies between three different height canopy levels. We found that temperature data did not differ between height levels, but relative humidity was significantly higher in the lowest parts. In addition, overstory individuals were the first to start autumn phases followed by mesostory and understory trees. Leaf colouring and fall for understory trees appeared 31 and 23 days later compared to overstory trees. The transition of autumn phases (from the beginning of leaf colouring until the end of leaf fall) was most and significantly extended for overstory trees (mean of 62 days), followed by mesostory (46 days) and understory (38 days). Understory individuals started leaf colouring even 4 days after the onset of overstory leaf fall evidencing phenological avoidance between life stages. Besides this analysis of life stages we also found that upper canopy parts of individual trees were characterized by the earliest appearance of autumn phases; mean difference in onset of leaf colouring and fall between upper and lower levels was in each case -11 days. Mean peak dates did not differ between the highest canopy levels. Thus, transition of autumn phases was fastest for the lowest canopy level (mean of 19 days) than for the highest levels (35 days). Our results suggest that the observed differences were probably not related to temperature but to microclimatic variations in relative humidity and light availability. Furthermore, autumn phases of lower individuals (mesostory and understory) and lower canopy height parts were associated with a shortened transition of autumn phenological phases, probably also associated with fewer branches and leaves that might facilitate the synchronization of phenology. Since phenological development can considerably differ, generalizations are limited when considering trees of different life stages within a forest. Further studies should focus on autumn light conditions to investigate its influence on phenology and the possible gain of light acquisition during phenological avoidance.

Gressler, Eliana; Jochner, Susanne; Capdevielle-Vargas, Renée; Morellato, Patrícia; Menzel, Annette

2014-05-01

120

Unraveling the growth determinism of Fagus sylvatica: a hybrid data-model approach  

NASA Astrophysics Data System (ADS)

The physiological processes underlying the limitation of forest growth are still under debate. Growth has long been considered as a carbone (C) limited process (Sala et al., 2012). As a matter of facts, a recent global meta-analysis has shown good agreements between assimilated C and forest productivity (Litton et al., 2007). Consequently, a majority of the process-based productivity models considers growth as a fraction of the net primary production (NPP) (Lacointe et al., 2000; Sitch et al., 2003. However, investigations at the stand scale report conflicting results (Rocha et al., 2006, Mund et al., 2010) and are not systematically consistent with a strict C limitation of growth, thus challenging the C-centric paradigm. The mechanisms that potentially degrade the link between NPP and growth include: i) the direct effect of environmental factors on growth (Zweifel et al., 2006, Körner et al., 2003), ii) the temporal variability of the growth allocation coefficient, due either to ontogeny (Genet et al., 2009), or to the initial physiological state of the tree i.e. to the reaction to past conditions. Indeed, many dendrochronological and ecological studies have shown a correlation between growth and climatic factors of the previous years (e.g. Lebourgeois et al., 2005; Richardson et al., 2012). In this work, we used a hybrid data model approach in order to assess the determinant of Fagus sylvatica stem growth along a spatial gradient across France. Despite they could brought essential insight on tree functioning, intra-specific studies across contrasted sites are still lacking in the current debate. Standardized annual growth data series at the stand scale were calculated using circumference inventories and dendrochronological series on 17 plots of the RENECOFOR network. We used the process-based model CASTANEA, thoroughly validated in long term flux simulation across Europe (e.g. Delpierre et al. 2009), to simulate the annual NPP of the corresponding periods. We then investigated the dependency of annual growth on NPP, age and variables describing direct or indirect climatic conditions of the current (n) and the previous (n-1) year (e.g. simulated soil water content, sum of winter negative temperature, simulated growth phenology). Analyses were conducted as follows: first we used a Random Forest learning machine (RF) to select important variables and to obtain information on the form of the dependencies. We then formalized this information within the linear model framework to quantify the variability attributable to each factors and to conduct valid statistical tests. RF analysis revealed that NPP was the most important variable explaining growth, with a quasi-linear partial effect. The 2 other selected variables quantified the hydric stress of year (n) and (n-1), and impacted growth with high threshold effects. Analysis of covariance then revealed that both hydric variables significantly affect the NPP-growth relationship. The retained variables explained 29% of the growth variability. Growth of F. sylvatica is under complex control, involving C assimilation, direct effect of water shortage and lagged response to past condition. We used these results to implement in the CASTANEA model a new conceptual allocation scheme, validated at regional scale.

Guillemot, Joannès; Martin-StPaul, Nicolas; Delpierre, Nicolas; François, Christophe; Soudani, Kamel; Restoux, Gwendal; Dufrêne, Eric

2013-04-01

121

Draft Genome Sequences for Canadian Isolates of Pectobacterium carotovorum subsp. brasiliense with Weak Virulence on Potato  

PubMed Central

Pectobacterium carotovurum subsp. brasiliense causes soft rot and blackleg diseases on potato. Here, we report the draft genome sequences of three weakly virulent P. carotovurum subsp. brasiliense strains isolated in Canada. Analysis of these genome sequences will help to pinpoint differences in virulence among P. carotovurum subsp. brasiliense strains from tropical/subtropical and temperate regions, such as Canada and United States. A small number of key factors for adaptation to this bacterium's specific environmental niche were also evaluated. PMID:25858837

Yuan, Kat (Xiaoli); Cullis, Jeff; Lévesque, C. André; Chen, Wen; Lewis, Christopher T.; De Boer, Solke H.

2015-01-01

122

Draft Genome Sequences for Canadian Isolates of Pectobacterium carotovorum subsp. brasiliense with Weak Virulence on Potato.  

PubMed

Pectobacterium carotovurum subsp. brasiliense causes soft rot and blackleg diseases on potato. Here, we report the draft genome sequences of three weakly virulent P. carotovurum subsp. brasiliense strains isolated in Canada. Analysis of these genome sequences will help to pinpoint differences in virulence among P. carotovurum subsp. brasiliense strains from tropical/subtropical and temperate regions, such as Canada and United States. A small number of key factors for adaptation to this bacterium's specific environmental niche were also evaluated. PMID:25858837

Li, Xiang Sean; Yuan, Kat Xiaoli; Cullis, Jeff; Lévesque, C André; Chen, Wen; Lewis, Christopher T; De Boer, Solke H

2015-01-01

123

Isolation by genomic subtraction of DNA probes specific for Erwinia carotovora subsp. atroseptica.  

PubMed Central

Erwinia carotovora subsp. atroseptica is a pathogen of potatoes in Europe because of its ability to induce blackleg symptoms early in the growing season. However, E. carotovora subsp. carotovora is not able to produce such severe symptoms under the same conditions. On the basis of the technique described by Straus and Ausubel (Proc. Natl. Acad. Sci. USA 87:1889-1893, 1990), we isolated DNA sequences of E. carotovora subsp. atroseptica 86.20 that were absent from the genomic DNA of E. carotovora subsp. carotovora CH26. Six DNA fragments ranging from ca. 180 to 400 bp were isolated, cloned, and sequenced. Each fragment was further hybridized with 130 microorganisms including 87 E. carotovora strains. One probe was specific for typical E. carotovora subsp. atroseptica strains, two probes hybridized with all E. carotovora subsp. atroseptica strains and with a few E. carotovora subsp. carotovora strains, and two probes recognized only a subset of E. carotovora subsp. atroseptica strains. The last probe was absent from the genomic DNA of E. carotovora subsp. carotovora CH26 but was present in the genomes of many strains, including those of other species and genera. This probe is homologous to the putP gene of Escherichia coli, which encodes a proline carrier. Further use of the probes is discussed. Images PMID:8117082

Darrasse, A; Kotoujansky, A; Bertheau, Y

1994-01-01

124

Efficient transformation of Mesorhizobium huakuii subsp. rengei and Rhizobium species  

Microsoft Academic Search

The transformation of Mesorhizobium huakuii subsp. rengei B3 with either pBBR122 or pKT230 was carried out. We determined the optimal conditions required for transformation by electroporation and obtained up to 105 CFU\\/?g pBBR122. Plasmids prepared from strain B3 yielded higher transformation efficiency than those from various dam or dcm mutant strains of Escherichia coli. This result suggests that a high

Makoto Hayashi; Yoshiaki Maeda; Yoshiteru Hashimoto; Yoshikatsu Murooka

2000-01-01

125

Francisella tularensis subsp. tularensis Group A.I, United States  

PubMed Central

We used whole-genome analysis and subsequent characterization of geographically diverse strains using new genetic signatures to identify distinct subgroups within Francisella tularensis subsp. tularensis group A.I: A.I.3, A.I.8, and A.I.12. These subgroups exhibit complex phylogeographic patterns within North America. The widest distribution was observed for A.I.12, which suggests an adaptive advantage. PMID:24755401

Birdsell, Dawn N.; Johansson, Anders; Öhrman, Caroline; Kaufman, Emily; Molins, Claudia; Pearson, Talima; Gyuranecz, Miklós; Naumann, Amber; Vogler, Amy J.; Myrtennäs, Kerstin; Larsson, Pär; Forsman, Mats; Sjödin, Andreas; Gillece, John D.; Schupp, James; Petersen, Jeannine M.; Keim, Paul

2014-01-01

126

Chromones and flavanones from artemisia campestris subsp. maritima  

Microsoft Academic Search

From the acetone extract of Artemisia campestris subsp. maritima six flavanones, two chromones and the coumarin scopoletin were isolated. 5-Hydroxy-7-methoxychromone and 5,7-dimethoxychromone are new compounds, while the flavanone eriodictyol-7,3?-dimethyl ether is reported for the first time in this species. The structures were elucidated by 1D and 2D NMR techniques. The unequivocal assignments of carbon resonances, mainly made by using 1D

João M. J. Vasconcelos; Artur M. S. Silva; José A. S. Cavaleiro

1998-01-01

127

Proposal for 'Candidatus Mycoplasma haemomuris subsp. musculi' in mice, and 'Candidatus Mycoplasma haemomuris subsp. ratti' in rats.  

PubMed

Mycoplasma haemomuris is causative of infectious anaemia or splenomegaly in rodents. We examined the nucleotide sequences of the non-ribosomal genes, rnpB and dnaK, in strains of the species M. haemomuris detected in small field mice and black rats. rnpB nucleotide sequences in strains of the species M. haemomuris isolated from small field mice and black rats had only 89?% sequence similarity, suggesting their separation into two distinct subgroups. dnaK had a nucleotide sequence similarity of 84?% between the subgroups. These results support the classification of M. haemomuris into two genetically distinct subgroups. Here we propose the establishment of these subgroups as 'Candidatus Mycoplasma haemomuris subsp. musculi', detected in small field mice (Apodemus argenteus), and 'Candidatus Mycoplasma haemomuris subsp. ratti', detected in black rats (Rattus rattus). PMID:25406232

Harasawa, Ryô; Fujita, Hiromi; Kadosaka, Teruki; Ando, Shuji; Rikihisa, Yasuko

2015-02-01

128

Comparison of pectic enzymes produced by Erwinia chrysanthemi, Erwinia carotovora subsp. carotovora, and Erwinia carotovora subsp. atroseptica.  

PubMed Central

Erwinia spp. that cause soft-rot diseases in plants produce a variety of extracellular pectic enzymes. To assess the correlation between patterns of pectic enzyme production and taxonomic classification, we compared the enzymes from representative strains. Supernatants obtained from polygalacturonate-grown cultures of nine strains of Erwinia chrysanthemi, three strains of E. carotovora subsp. carotovora, and three strains of E. carotovora subsp. atroseptica were concentrated and subjected to ultrathin-layer polyacrylamide gel isoelectric focusing. Pectate lyase, polygalacturonase, and exo-poly-alpha-D-galacturonosidase activities were visualized by staining diagnostically buffered pectate-agarose overlays with ruthenium red after incubation of the overlays with the isoelectric focusing gels. The isoelectric focusing profiles of pectate lyase and polygalacturonase were nearly identical for strains of E. carotovora subsp. carotovora and E. carotovora subsp. atroseptica, showing three pectate lyase isozymes with isoelectric points higher than 8.7 and a polygalacturonase with pI of ca. 10.2. Isoelectric focusing profiles of the E. chrysanthemi pectic enzymes were substantially different. Although there was considerable intraspecific heterogeneity, all strains produced at least four isozymes of pectate lyase, which could be divided into three groups: basic (pI, ca. 9.0 to 10.0), slightly basic (pI, ca. 7.0 to 8.5), and acidic (pI, ca. 4.0 to 5.0). Several strains of E. chrysanthemi also produced a single form of exo-poly-alpha-D-galacturonosidase (pI, ca. 8.0).(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:3752996

Ried, J L; Collmer, A

1986-01-01

129

A Change in a Single Midgut Receptor in the Diamondback Moth (Plutella xylostella) Is Only in Part Responsible for Field Resistance to Bacillus thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai  

PubMed Central

A population (SERD3) of the diamondback moth (Plutella xylostella L.) with field-evolved resistance to Bacillus thuringiensis subsp. kurstaki HD-1 (Dipel) and B. thuringiensis subsp. aizawai (Florbac) was collected. Laboratory-based selection of two subpopulations of SERD3 with B. thuringiensis subsp. kurstaki (Btk-Sel) or B. thuringiensis subsp. aizawai (Bta-Sel) increased resistance to the selecting agent with little apparent cross-resistance. This result suggested the presence of independent resistance mechanisms. Reversal of resistance to B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai was observed in the unselected SERD3 subpopulation. Binding to midgut brush border membrane vesicles was examined for insecticidal crystal proteins specific to B. thuringiensis subsp. kurstaki (Cry1Ac), B. thuringiensis subsp. aizawai (Cry1Ca), or both (Cry1Aa and Cry1Ab). In the unselected SERD3 subpopulation (ca. 50- and 30-fold resistance to B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai), specific binding of Cry1Aa, Cry1Ac, and Cry1Ca was similar to that for a susceptible population (ROTH), but binding of Cry1Ab was minimal. The Btk-Sel (ca. 600-and 60-fold resistance to B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai) and Bta-Sel (ca. 80-and 300-fold resistance to B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai) subpopulations also showed reduced binding to Cry1Ab. Binding of Cry1Ca was not affected in the Bta-Sel subpopulation. The results suggest that reduced binding of Cry1Ab can partly explain resistance to B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. aizawai. However, the binding of Cry1Aa, Cry1Ac, and Cry1Ca and the lack of cross-resistance between the Btk-Sel and Bta-Sel subpopulations also suggest that additional resistance mechanisms are present. PMID:16535597

Wright, D. J.; Iqbal, M.; Granero, F.; Ferre, J.

1997-01-01

130

Biomass and nutrient content of sessile oak ( Quercus petraea (Matt.) Liebl.) and beech ( Fagus sylvatica L.) stem and branches in a mixed stand in southern Belgium  

Microsoft Academic Search

Accurate estimates of the amounts of nutrients immobilised in the organs and tissues of different tree species are of prime importance to make appropriate tree species selection and determine the harvesting regime that will ensure forest sustainability. Sixteen sessile oaks (Quercus petraea (Matt.) Liebl.) (64–129years; stem diameters: 17–57cm) and twelve beeches (Fagus sylvatica L.) (43–86years; stem diameters: 9–50cm) were destructively

Frédéric André; Mathieu Jonard; Quentin Ponette

2010-01-01

131

Response to canopy opening does not act as a filter to Fagus sylvatica and Acer sp. advance regeneration in a mixed temperate forest  

Microsoft Academic Search

– \\u000a \\u000a • In mixed-species forest stands, large losses in tree species diversity often occur during the regeneration phase. In a former\\u000a coppice-with-standards, we investigated whether the limiting stage in the recruitment process of advance regeneration is the\\u000a immediate seedling response to canopy release. Experimental canopy gaps were opened and the survival and growth of advance\\u000a seedlings (Fagus sylvatica, Acer pseudoplatanus,

Blandine Caquet; Pierre Montpied; Erwin Dreyer; Daniel Epron; Catherine Collet

2010-01-01

132

Inter-annual and seasonal variability of radial growth, wood density and carbon isotope ratios in tree rings of beech ( Fagus sylvatica ) growing in Germany and Italy  

Microsoft Academic Search

We investigated the variability of tree-ring width, wood density and 13C\\/12C in beech tree rings (Fagus sylvatica L.), and analyzed the influence of climatic variables and carbohydrate storage on these parameters. Wood cores were taken from dominant beech trees in three stands in Germany and Italy. We used densitometry to obtain density profiles of tree rings and laser-ablation-combustion-GC-IRMS to estimate

M. V. Skomarkova; E. A. Vaganov; M. Mund; A. Knohl; P. Linke; A. Boerner; E.-D. Schulze

2006-01-01

133

Acceleration of leaf senescence in Fagus sylvatica L. by low levels of tropospheric ozone demonstrated by leaf colour, chlorophyll fluorescence and chloroplast ultrastructure  

Microsoft Academic Search

From April 1988 to October 1991 3-year-old seed propagated beech (Fagus sylvatica L.) trees were exposed in open-top chambers to four different levels of air pollution: (1) charcoal filtered air, (2) ambient\\u000a air, (3) ambient air plus 30 nl 1-1 ozone during the summer, and (4) ambient air plus 30 nl 1-1 ozone during the summer and 20 nl 1-1

Teis N. Mikkelsen; Henning S. Heide-Jørgensen

1996-01-01

134

A comparison of four different fine root production estimates with ecosystem carbon balance data in a Fagus–Quercus mixed forest  

Microsoft Academic Search

The controversy on how to measure fine root production of forests (P) most accurately continues. We applied four different approaches to determine annual rates of P in an old-growth temperate Fagus sylvatica–Quercus petraea stand: sequential soil coring with minimum–maximum calculation, sequential coring with compartmental flow calculation, the ingrowth core method, and a recently developed root chamber method for measuring the

Dietrich Hertel; Christoph Leuschner

2002-01-01

135

Complete Genome Sequence of the Strong Mutator Salmonella enterica subsp. enterica Serotype Heidelberg Strain B182  

E-print Network

, Leclerc et al. (5) detected a high incidence (over 1%) of mutators among pathogenic SalmonellaComplete Genome Sequence of the Strong Mutator Salmonella enterica subsp. enterica Serotype the first complete genome sequence of the Salmonella enterica subsp. enterica serotype Heidelberg B182

Paris-Sud XI, Université de

136

Pohlia nutans subsp. schimperi (Mull.Hal.) Nyholm, a neglected Nordic moss in Central Europe  

E-print Network

Pohlia nutans subsp. schimperi (Mu¨ll.Hal.) Nyholm, a neglected Nordic moss in Central Europe Pohlia nutans subsp. schimperi is recognized as a distinct taxon, differing from ssp. nutans by the pink: Pohlia schimperi, P. nutans, taxonomy, ecology, glacial relict, Austria, Czech Republic, Poland

Kucera, Jan

137

Pohlia nutans subsp. schimperi (Müll.Hal.) Nyholm, a neglected Nordic moss in Central Europe  

Microsoft Academic Search

SUMMARY Pohlia nutans subsp. schimperi is recognized as a distinct taxon, differing from ssp. nutans by the pink to purple coloration of its leaves and a dioicous or polyoicous, rather than paroicous, sexual condition. We review the contrasting reports about the sexuality of these plants, as well as their nomenclatural history, and demonstrate their synonymy with P. nutans subsp. purpurascens

Heribert Köckinger; Jan Ku?era; Adam Stebel

2005-01-01

138

Complete Genome Sequence of Mycobacterium avium subsp. paratuberculosis, Isolated from Human Breast Milk  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is the etiologic agent of Johne’s disease in ruminants and has also been associated with human Crohn’s disease. We report the complete genome sequence of M. avium subsp. paratuberculosis, isolated from the breast milk of a Crohn’s disease patient. This sequence has high identity with characterized strains recovered from cattle. PMID:24503996

Li, Lingling; Mwangi, Michael; Cote, Rebecca; Raygoza Garay, Juan A.

2014-01-01

139

A17, the First Sequenced Strain of Lactococcus lactis subsp. cremoris with Potential Immunomodulatory Functions  

PubMed Central

Lactococcus lactis subsp. cremoris A17, isolated from Taiwan fermented cabbage, is the first sequenced strain of L. lactis subsp. cremoris with immunomodulatory activity and antiallergic functions. The resulting A17 draft genome contains 2,679,936 bp and indicates that A17 is a potential exopolysaccharide-producing strain without any known virulence gene. PMID:25676767

Yang, Chih-Hsien; Wu, Chien-Chen; Cheng, Wei-Shen; Chung, Ming-Chuan

2015-01-01

140

Complete genome sequence of Leuconostoc mesenteroides subsp. mesenteroides strain J18, isolated from kimchi.  

PubMed

Leuconostoc mesenteroides subsp. mesenteroides is one of the most predominant lactic acid bacterial groups during kimchi fermentation. Here, we report the complete genome sequence of L. mesenteroides subsp. mesenteroides J18, which was isolated from kimchi. The genome of the strain consists of a 1,896,561-bp chromosome and five plasmids. PMID:22247530

Jung, Ji Young; Lee, Seung Hyeon; Lee, Se Hee; Jeon, Che Ok

2012-02-01

141

PCR-Based Identification of Klebsiella pneumoniae subsp. rhinoscleromatis, the Agent of Rhinoscleroma  

E-print Network

PCR-Based Identification of Klebsiella pneumoniae subsp. rhinoscleromatis, the Agent of this study was to develop two simple PCR assays. We took advantage of the fact that all Klebsiella pneumoniae assayed on the 76 other Klebsiella capsular types. Further, to discriminate Klebsiella pneumoniae subsp

Paris-Sud XI, Université de

142

Development and Characterization of Monoclonal Antibodies and Aptamers Against Major Antigens of Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Specific antibodies, available in unlimited quantities, have not been produced against Mycobacterium avium subsp. paratuberculosis, the bacterium that causes Johne’s disease (JD). To fill this gap in JD research, monoclonal antibodies (mAbs) against M. avium subsp. paratuberculosis were produced fr...

143

Genomic Diversity of Erwinia carotovora subsp. carotovora and Its Correlation with Virulence  

Microsoft Academic Search

We used genetic and biochemical methods to examine the genomic diversity of the enterobacterial plant pathogen Erwinia carotovora subsp. carotovora. The results obtained with each method showed that E. caroto- vora subsp. carotovora strains isolated from one ecological niche, potato plants, are surprisingly diverse compared to related pathogens. A comparison of 23 partial mdh sequences revealed a maximum pairwise difference

Mee-Ngan Yap; Jeri D. Barak; Amy O. Charkowski

2004-01-01

144

A Gene Specific to Mycobacterium avium subsp. paratuberculosis, But Only at the Transcription-translation Level  

Technology Transfer Automated Retrieval System (TEKTRAN)

There is no known antibody that detects M. avium subsp paratuberculosis and does not cross react with other M. avium subspecies. In the present study, a monoclonal antibody was identified from mice immunized with a cell membrane fraction of M. avium subsp paratuberculosis strain K-10. This antibod...

145

A UV Tolerant Mutant of Bacillus thuringiensis subsp. kurstaki Producing Melanin  

E-print Network

A UV Tolerant Mutant of Bacillus thuringiensis subsp. kurstaki Producing Melanin Deepak Saxena,1 thuringiensis subsp. kurstaki, producing a dark brown pigment, identified as melanin, was studied. Bt-m had that production of melanin by various microorganisms protects their susceptibility to oxidative damage caused

Zaritsky, Arieh

146

Complete genome sequence of Mycobacterium avium subsp. paratuberculosis, isolated from human breast milk  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp paratuberculosis is the etiologic agent of Johne’s disease. We report the draft genome sequences of six M. avium subsp paratuberculosis isolates obtained from diverse hosts including bison, cattle and sheep. These sequences will deepen our understanding of host association ...

147

Complete Genome Sequence of Salmonella enterica subsp. enterica Serovar Enteritidis Strain SEJ  

PubMed Central

Salmonella enterica constitutes a group of enteric pathogens with a broad host range, including humans, reptiles, and birds. S. enterica subsp. enterica is a common cause of inflammatory diarrhea in humans. We present the draft genome of S. enterica subsp. enterica serovar Enteritidis strain SEJ, including a 59-kbp plasmid. PMID:25342692

Bishop-Lilly, K. A.; Frey, K. G.; Daligault, H. E.; Davenport, K. W.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Chertkov, O.; Freitas, T.; Jaissle, J.; Koroleva, G. I.; Ladner, J. T.; Minogue, T. D.; Palacios, G. F.; Redden, C. L.; Xu, Y.

2014-01-01

148

Complete Genome Sequence of Type Strain Campylobacter fetus subsp. venerealis NCTC 10354T  

PubMed Central

Campylobacter fetus subsp. venerealis is the etiologic agent of bovine genital campylobacteriosis, a sexually transmitted disease of cattle that is of worldwide importance. The complete sequencing and annotation of the genome of the type strain C. fetus subsp. venerealis NCTC 10354T are reported. PMID:21952544

Stynen, Ana Paula Reinato; Lage, Andrey Pereira; Moore, Robert J.; Rezende, Antonio Mauro; de Resende, Vivian D'Afonseca da Silva; Ruy, Patricia de Cássia; Daher, Nesley; Resende, Daniela de Melo; de Almeida, Sintia Silva; Soares, Siomar de Castro; de Abreu, Vinicius Augusto Carvalho; Rocha, Aryane Aparecida C. Magalhães; dos Santos, Anderson Rodrigues; Barbosa, Eudes Guilherme Vieira; Costa, Danielle Fonseca; Dorella, Fernanda Alves; Miyoshi, Anderson; de Lima, Alex Ranieri Jerônimo; Campos, Frederico Davi da Silva; de Sá, Pablo Gomes; Lopes, Thiago Souza; Rodrigues, Ryan Mauricio Araujo; Carneiro, Adriana Ribeiro; Leão, Thiago; Cerdeira, Louise Teixeira; Ramos, Rommel Thiago Jucá; Silva, Artur; Azevedo, Vasco; Ruiz, Jerônimo C.

2011-01-01

149

Composicion de los aceites esenciales de Nepeta nepetella subsparagonensis, Nepeta coerulea subsp. coerulea y Nepeta cataria  

Microsoft Academic Search

The essential oils of Nepeta coerulea subsp. coerulea, Nepeta nepetella subsp. aragonensis and Nepeta cataria. - Essential oil composition of three iberian Nepeta were studied by chromatographic and spectrometric methods. The essential oils are constituted mainly of diasteroisomers of nepetalactone. These compounds may be used as chemosystematic characters.

Arturo Velasco Negueruela; Margarita Mata Rico; Paulina Bermejo Benito; Maria José Pérez-Alonso

1988-01-01

150

Beech regeneration of seed and root sucker origin: A comparison of morphology, growth, survival, and response to defoliation  

Microsoft Academic Search

American beech (Fagus grandifolia Ehrh.) reproduces sexually, and vegetatively by root suckers. Although many studies have investigated its regeneration response, most did not account for differences that may exist between its two modes of reproduction. This study was performed in an old-growth Acer - Fagus forest in southern Quebec, where beech bark disease had only a minor effect at the

Marilou Beaudet; Christian Messier

2008-01-01

151

Isolation of Lactococcus lactis subsp. cremoris from nature by colony hybridization with rRNA probes.  

PubMed Central

Lactococcus lactis subsp. cremoris is widely used in the manufacture of fermented milk products. Despite numerous attempts, efforts to isolate new strains by traditional plating and identification methods have not been successful. Previously, we described oligonucleotide probes for 16S rRNAs which could be used to discriminate L. lactis subsp. cremoris from related strains. These probes were used in colony hybridization experiments to screen large numbers of colonies obtained from enrichment cultures. A total of 170 strains of L. lactis were isolated from six milk samples, two colostrum samples, and one corn sample by using oligonucleotide probe 212RLa specific for the species L. lactis. Fifty-nine of these isolates also hybridized to L. lactis subsp. cremoris-specific probe 68RCa, and 26 of the strains which hybridized to the L. lactis subsp. cremoris-specific probe had the L. lactis subsp. cremoris phenotype. Images PMID:7506898

Salama, M S; Sandine, W E; Giovannoni, S J

1993-01-01

152

Assessing the Inactivation of Mycobacterium avium subsp. paratuberculosis during Composting of Livestock Carcasses  

PubMed Central

Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle mortalities. PMID:23503307

Tkachuk, Victoria L.; Krause, Denis O.; McAllister, Tim A.; Buckley, Katherine E.; Reuter, Tim; Hendrick, Steve

2013-01-01

153

Bibenzyls and dihydroisocoumarins from white salsify ( Tragopogon porrifolius subsp. porrifolius)  

Microsoft Academic Search

A phytochemical investigation of three accessions of Tragopogon porrifolius L. subsp. porrifolius (Asteraceae, Lactuceae) yielded three new bibenzyl derivatives, 5,4?-dihydroxy-3-?-l-rhamnopyranosyl-(1?3)-?-d-xylopyranosyloxybibenzyl, 2-carboxyl-3,4?-dihydroxy-5-?-d-xylopyranosyloxybibenzyl, tragopogonic acid (2?carboxyl-3?,5?,4?-trihydroxyphenylethanone) and three dihydroisocoumarin derivatives, including the new natural product 6-O-methylscorzocreticoside I. One of the isolated bibenzyl derivatives is considered to be a precursor to the biosynthesis of dihydroisocoumarins. Structures of new compounds were established by HR

Christian Zidorn; Ulrike Lohwasser; Susanne Pschorr; Daniela Salvenmoser; Karl-Hans Ongania; Ernst P. Ellmerer; Andreas Börner; Hermann Stuppner

2005-01-01

154

Horizontal gene transfer and recombination in Streptococcus dysgalactiae subsp. equisimilis  

PubMed Central

Streptococcus dysgalactiae subsp. equisimilis (SDSE) is a human pathogen that colonizes the skin or throat, and causes a range of diseases from relatively benign pharyngitis to potentially fatal invasive diseases. While not as virulent as the close relative Streptococcus pyogenes the two share a number of virulence factors and are known to coexist in a human host. Both pre- and post-genomic studies have revealed that horizontal gene transfer (HGT) and recombination occurs between these two organisms and plays a major role in shaping the population structure of SDSE. This review summarizes our current knowledge of HGT and recombination in the evolution of SDSE. PMID:25566202

McNeilly, Celia L.; McMillan, David J.

2014-01-01

155

Lipase and Esterase Activities of Propionibacterium freudenreichii subsp. freudenreichii  

PubMed Central

The lipase and esterase activities of eight strains of dairy Propionibacterium freudenreichii subsp. freudenreichii were studied. A lipase activity was detected on whole cells and in the culture supernatant. The highest activity was expressed at 45°C and pH 6.8. An esterase activity was also detected in the culture medium. The electrophoresis of the intracellular fractions of the cells revealed from three to six different esterase activities. Two esterases were common to all the strains. The substrate specificity was dependent on each esterase, but no activity was revealed, in our experimental conditions, on ester substrates with a chain length longer than that of butyrate. PMID:16349102

Dupuis, C.; Corre, C.; Boyaval, P.

1993-01-01

156

Spatial and altitudinal bioclimatic zones of the Italian peninsula identified from a beech ( Fagus sylvatica L.) tree-ring network  

NASA Astrophysics Data System (ADS)

A network of 24 beech ( Fagus sylvatica L.) tree-ring chronologies has been developed for the Italian peninsula. Principal component and cluster analyses were used to identify geographical and altitudinal patterns of tree growth. Correlations and response functions were then applied to the main modes of tree-ring variability to uncover climatic signals. In a landscape occupied by humans for millennia, this approach provided a detailed quantitative ecological characterization of forest types. Altitude was significantly correlated with dendrochronological parameters. The Alps and northern Apennines could be distinguished from the central-southern Apennines. In central Italy, we recognized three different vegetation belts occupied by beech forests, from low- to high-elevation sites. Summer drought impacted beech growth with different intensity at different elevations, depending on the onset and duration of the growing season. Moreover, low-elevation beech forests showed a distinct late spring climate signal, which was opposite to that of high-elevation sites. The coherent geographical and ecological patterns of tree-ring variability suggest that dendrochronological networks help define bioclimatic zones and forest types.

Piovesan, Gianluca; Biondi, Franco; Bernabei, Mauro; Di Filippo, Alfredo; Schirone, Bartolomeo

2005-05-01

157

Quantifying ozone uptake and its effects on the stand level of common beech (Fagus sylvatica L.) in Southern Germany.  

PubMed

Stand level O(3) fluxes were calculated using water balance calculations for 21 Common beech (Fagus sylvatica L.) stands and O(3) data from 20 monitoring stations in Southern Germany. For this intention, the daily loss of water by evapotranspiration per stand area was set against the daily O(3) uptake. During the last 30 years, O(3) uptake ranges between 0 and 187 mmol ha(-1) d(-1) per stand area. Cumulative O(3) uptake (CUO(3)), ranging between 0.1 and 0.7 mmol m(-2) yr(-1) per stand area, shows increasing trends since 1971 with considerably greater values at high altitudes. Effects in radial growth were used to derive an initial approximate critical threshold value for O(3) impacts on the vitality and growth of mature beech stands in Southern Germany. It is concluded that this concept of O(3) flux estimation in combination with dendroecological analyses offers both a site specific and regional applicable approach to derive new critical levels for O(3). PMID:15572218

Dittmar, Christoph; Pfaffelmoser, Klaus; Rötzer, Thomas; Elling, Wolfram

2005-03-01

158

Model-based analysis of avoidance of ozone stress by stomatal closure in Siebold's beech (Fagus crenata)  

PubMed Central

Background and Aims Resistance of plants to ozone stress can be classified as either avoidance or tolerance. Avoidance of ozone stress may be explained by decreased stomatal conductance during ozone exposure because stomata are the principal interface for entry of ozone into plants. In this study, a coupled photosynthesis–stomatal model was modified to test whether the presence of ozone can induce avoidance of ozone stress by stomatal closure. Methods The response of Siebold's beech (Fagus crenata), a representative deciduous tree species, to ozone was studied in a free-air ozone exposure experiment in Japan. Photosynthesis and stomatal conductance were measured under ambient and elevated ozone. An optimization model of stomata involving water, CO2 and ozone flux was tested using the leaf gas exchange data. Key Results The data suggest that there are two phases in the avoidance of ozone stress via stomatal closure for Siebold's beech: (1) in early summer ozone influx is efficiently limited by a reduction in stomatal conductance, without any clear effect on photosynthetic capacity; and (2) in late summer and autumn the efficiency of ozone stress avoidance was decreased because the decrease in stomatal conductance was small and accompanied by an ozone-induced decline of photosynthetic capacity. Conclusions Ozone-induced stomatal closure in Siebold's beech during early summer reduces ozone influx and allows the maximum photosynthetic capacity to be reached, but is not sufficient in older leaves to protect the photosynthetic system. PMID:23904447

Hoshika, Yasutomo; Watanabe, Makoto; Inada, Naoki; Koike, Takayoshi

2013-01-01

159

Phosphite protects Fagus sylvatica seedlings towards Phytophthora plurivora via local toxicity, priming and facilitation of pathogen recognition.  

PubMed

Phytophthora plurivora causes severe damage on Fagus sylvatica and is responsible for the extensive decline of European Beech throughout Europe. Unfortunately, no effective treatment against this disease is available. Phosphite (Phi) is known to protect plants against Phytophthora species; however, its mode of action towards P. plurivora is still unknown. To discover the effect of Phi on root infection, leaves were sprayed with Phi and roots were subsequently inoculated with P. plurivora zoospores. Seedling physiology, defense responses, colonization of root tissue by the pathogen and mortality were monitored. Additionally the Phi concentration in roots was quantified. Finally, the effect of Phi on mycelial growth and zoospore formation was recorded. Phi treatment was remarkably efficient in protecting beech against P. plurivora; all Phi treated plants survived infection. Phi treated and infected seedlings showed a strong up-regulation of several defense genes in jasmonate, salicylic acid and ethylene pathways. Moreover, all physiological parameters measured were comparable to control plants. The local Phi concentration detected in roots was high enough to inhibit pathogen growth. Phi treatment alone did not harm seedling physiology or induce defense responses. The up-regulation of defense genes could be explained either by priming or by facilitation of pathogen recognition of the host. PMID:24489973

Dalio, Ronaldo J D; Fleischmann, Frank; Humez, Martina; Osswald, Wolfgang

2014-01-01

160

Raman spectroscopic investigation of (13)CO 2 labeling and leaf dark respiration of Fagus sylvatica L. (European beech).  

PubMed

An important issue, in times of climate change and more extreme weather events, is the investigation of forest ecosystem reactions to these events. Longer drought periods stress the vitality of trees and promote mass insect outbreaks, which strongly affect ecosystem processes and services. Cavity-enhanced Raman gas spectrometry was applied for online multi-gas analysis of the gas exchange rates of O2 and CO2 and the labeling of Fagus sylvatica L. (European beech) seedlings with (13)CO2. The rapid monitoring of all these gases simultaneously allowed for the separation of photosynthetic uptake of CO2 by the beech seedlings and a constant (12)CO2 efflux via respiration and thus for a correction of the measured (12)CO2 concentrations in course of the labeling experiment. The effects of aphid infestation with the woolly beech aphid (Phyllaphis fagi L.) as well as the effect of a drought period on the respirational gas exchange were investigated. A slightly decreased respirational activity of drought-stressed seedlings in comparison to normally watered seedlings was found already for a low drought intensity. Cavity-enhanced Raman gas monitoring of O2, (12)CO2, and (13)CO2 was proven to be a powerful new tool for studying the effect of drought stress and aphid infestation on the respirational activity of European beech seedlings as an example of important forest species in Central Europe. PMID:25577365

Keiner, Robert; Gruselle, Marie-Cécile; Michalzik, Beate; Popp, Jürgen; Frosch, Torsten

2015-03-01

161

Aeromonas salmonicida subsp. pectinolytica subsp. nov., a new pectinase-positive subspecies isolated from a heavily polluted river.  

PubMed

Aeromonas strains which phenotypically and genetically belong to the Aeromonas salmonicida species but that according to their phenotypic properties constitute a new subspecies have been isolated from the water of a heavily polluted river, the Matanza river, situated near the central district of Buenos Aires city. These strains were ascribed to the A. salmonicida species by using 65 biochemical tests and by DNA-DNA hybridization. They produce acid from -sorbitol, an unusual biochemical property found in a few members of the A. salmonicida species. They also utilize urocanic acid and do not ferment L-rhamnose or utilize LD-lactate, and are elastase- and gluconate-negative. The DNA relatedness was over 70%, the current limit accepted for the phylogenetic definition of a species, to the described A. salmonicida subspecies and nearly 100% within the new group of Aeromonas strains. Phenotypic differentiation from other A. salmonicida subspecies was readily achieved using the following characteristics: growth at 37 degrees C, melanin production, indole and Voges-Proskauer assays, growth on KCN broth, mannitol and sucrose fermentation and gas from glucose. A remarkable property of the strains of the new group was their ability to degrade polypectate, an unusual feature among Aeromonas species in general. The complete 16S rRNA gene of one strain of the new group was sequenced. Comparison with rDNA sequences of Aeromonas members available in databases revealed a close relationship between this strain and strains belonging to A. salmonicida subsp. salmonicida, masoucida and achromogenes, in agreement with the biochemical data. Since the new A. salmonicida strains constitute a tight genomic group that can be identified by phenotypic properties it was concluded that they represent a new subspecies for which the name Aeromonas salmonicida subsp. pectinolytica is proposed. The type strain of A. salmonicida subsp. pectinolytica is 34melT (= DSM 12609T). PMID:10843053

Pavan, M E; Abbott, S L; Zorzópulos, J; Janda, J M

2000-05-01

162

Real-time PCR for detection and differentiation of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus.  

PubMed

Strangles is a contagious equine disease caused by Streptococcus equi subsp. equi. In this study, clinical strains of S. equi (n=24) and Streptococcus equi subsp. zooepidemicus (n=24) were genetically characterized by sequencing of the 16S rRNA and sodA genes in order to devise a real-time PCR system that can detect S. equi and S. zooepidemicus and distinguish between them. Sequencing demonstrated that all S. equi strains had the same 16S rRNA sequence, whereas S. zooepidemicus strains could be divided into subgroups. One of these (n=12 strains) had 16S rRNA sequences almost identical with the S. equi strains. Interestingly, four of the strains biochemically identified as S. zooepidemicus were found by sequencing of the 16S rRNA gene to have a sequence homologous with Streptococcus equi subsp. ruminatorum. However, they did not have the colony appearance or the biochemical characteristics of the type strain of S. ruminatorum. Classification of S. ruminatorum may thus not be determined solely by 16S rRNA sequencing. Sequencing of the sodA gene demonstrated that all S. equi strains had an identical sequence. For the S. zooepidemicus strains minor differences were found between the sodA sequences. The developed real-time PCR, based on the sodA and seeI genes was compared with conventional culturing on 103 cultured samples from horses with suspected strangles or other upper respiratory disease. The real-time PCR system was found to be more sensitive than conventional cultivation as two additional field isolates of S. equi and four of S. zooepidemicus were detected. PMID:17531409

Båverud, V; Johansson, S K; Aspan, A

2007-10-01

163

Pseudomonas brassicacearum subsp. neoaurantiaca subsp. nov., orange-pigmented bacteria isolated from soil and the rhizosphere of agricultural plants.  

PubMed

A large group of 38 strains of saprophytic bacteria was isolated from soil and the rhizosphere of agricultural plants. The novel organisms were Gram-negative, aerobic, rod-shaped bacteria that produced a green fluorescent pigment, a red-orange diffusible pigment and a complex mixture of phloroglucinol derivates with antimicrobial activity. The latter have not been found in other bacteria, but are peculiar to ferns. The bacteria were vigorous denitrifiers that synthesized levan from sucrose and liquefied gelatin, but were found not to degrade aesculin, starch, agar, Tween 80 or DNA. Bacterial growth was found to occur at 4 degrees C but not at 40 degrees C. The predominant cellular fatty acids were 16 : 0, 16 : 1(n-7), 18 : 1(n-7) and 17 : 0 cyclo. The G+C content of the novel bacteria was 61.0-62.9 mol%. 16S rRNA gene sequence analysis indicated that the representative strain CIP 109457(T) had a clear affiliation with Pseudomonas sensu stricto groups, with the nearest relatives being Pseudomonas brassicacearum, P. thivervalensis, P. corrugata, P. mediterranea and P. kilonensis. DNA-DNA hybridization experiments showed that the group of isolated strains exhibited high levels of genetic relatedness (81-100 %), confirming that they are representatives of the same species. At the same time, they bound at low levels (4-46 %) with DNA of the type strains of their nearest relatives with the exception of P. brassicacearum; DNA binding of 90 % with the DNA of P. brassicacearum CIP 107059(T) suggested that the bacteria studied belong to this species. Analysis of taxonomic data indicated that the group of novel bacteria maintain a distinct phenotypic profile, allowing the description of novel subspecies within P. brassicacearum, for which the following names are proposed: Pseudomonas brassicacearum subsp. brassicacearum subsp. nov. (type strain DBK11(T) =CFBP 11706(T) =CIP 107059(T) =DSM 13227(T) =JCM 11938(T)) and Pseudomonas brassicacearum subsp. neoaurantiaca subsp. nov., with the type strain CIP 109457(T) (=ATCC 49054(T) =IMV 387(T) =VKM B-1524(T)). PMID:19622656

Ivanova, Elena P; Christen, Richard; Bizet, Chantal; Clermont, Dominique; Motreff, Laurence; Bouchier, Christiane; Zhukova, Natalia V; Crawford, Russell J; Kiprianova, Elena A

2009-10-01

164

Strong genetic differentiation between North American and European populations of Phytophthora alni subsp. uniformis.  

PubMed

Alder decline caused by Phytophthora alni has been one of the most important diseases of natural ecosystems in Europe during the last 20 years. The emergence of P. alni subsp. alni -the pathogen responsible for the epidemic-is linked to an interspecific hybridization event between two parental species: P. alni subsp. multiformis and P. alni subsp. uniformis. One of the parental species, P. alni subsp. uniformis, has been isolated in several European countries and, recently, in North America. The objective of this work was to assess the level of genetic diversity, the population genetic structure, and the putative reproduction mode and mating system of P. alni subsp. uniformis. Five new polymorphic microsatellite markers were used to contrast both geographical populations. The study comprised 71 isolates of P. alni subsp. uniformis collected from eight European countries and 10 locations in North America. Our results revealed strong differences between continental populations (Fst = 0.88; Rst = 0.74), with no evidence for gene flow. European isolates showed extremely low genetic diversity compared with the North American collection. Selfing appears to be the predominant mating system in both continental collections. The results suggest that the European P. alni subsp. uniformis population is most likely alien and derives from the introduction of a few individuals, whereas the North American population probably is an indigenous population. PMID:23095465

Aguayo, Jaime; Adams, Gerard C; Halkett, Fabien; Catal, Mursel; Husson, Claude; Nagy, Zoltán Á; Hansen, Everett M; Marçais, Benoît; Frey, Pascal

2013-02-01

165

Proposal to reclassify Brenneria quercina (Hildebrand and Schroth 1967) Hauben et al. 1999 into a new genus, Lonsdalea gen. nov., as Lonsdalea quercina comb. nov., descriptions of Lonsdalea quercina subsp. quercina comb. nov., Lonsdalea quercina subsp. iberica subsp. nov. and Lonsdalea quercina subsp. britannica subsp. nov., emendation of the description of the genus Brenneria, reclassification of Dickeya dieffenbachiae as Dickeya dadantii subsp. dieffenbachiae comb. nov., and emendation of the description of Dickeya dadantii.  

PubMed

Bacterial isolates from oak trees in Spain and Britain, showing symptoms of bark canker and Acute Oak Decline (AOD), respectively, were examined by a polyphasic approach. Both 16S rRNA gene sequencing and multilocus sequence analysis (MLSA), based on partial sequences of gyrB, rpoB, infB and atpD genes, revealed that the isolates were separated into two genetic groups according to their origin. Their closest phylogenetic relative was Brenneria quercina, the causal agent of drippy nut disease of oak, which clustered distant to the other species of the genus Brenneria. MLSA data for species of the genera Brenneria, Pectobacterium, Dickeya, Erwinia, Pantoea and Samsonia confirmed the polyphyletic nature of the genus Brenneria and indicated synonymy of Dickeya dadantii and Dickeya dieffenbachiae. DNA-DNA hybridization experiments confirmed this synonymy and also revealed DNA-DNA relatedness values of 58-73% between the new oak isolates and B. quercina. Phenotypic and/or chemotaxonomic methods allowed B. quercina and the two genetic groups of new oak isolates to be discriminated from other recognized species of the genus Brenneria and from members of the closely related genera Dickeya, Pectobacterium and Samsonia. Based on the data obtained, the following taxonomic proposals are made: (1) reclassification of B. quercina as the type species of a novel genus, Lonsdalea gen. nov., as Lonsdalea quercina comb. nov. (type strain LMG 2724(T)=ATCC 29281(T)=CCUG 48867(T)=CFBP 3617(T)=CIP 105201(T)=DSM 4561(T)=ICMP 1845(T)), (2) classification of the oak isolates as Lonsdalea quercina subsp. iberica subsp. nov. (type strain LMG26264(T)=NCPPB 4490(T)) and Lonsdalea quercina subsp. britannica subsp. nov. (type strain LMG 26267(T)=NCPPB 4481(T)) and leading to the automatic creation of Lonsdalea quercina subsp. quercina subsp. nov. (type strain LMG 2724(T)=ATCC 29281(T)), (3) emendation of the description of the genus Brenneria, and (4) reclassification of Dickeya dieffenbachiae as Dickeya dadantii subsp. dieffenbachiae comb. nov. (type strain LMG 25992(T)=CFBP 2051(T)), with the automatic creation of Dickeya dadantii subsp. dadantii subsp. nov. (type strain LMG 25991(T)=CFBP 1269(T)). PMID:21890733

Brady, Carrie L; Cleenwerck, Ilse; Denman, Sandra; Venter, Stephanus N; Rodríguez-Palenzuela, Pablo; Coutinho, Teresa A; De Vos, Paul

2012-07-01

166

Rapid Expression of Mycobacterium avium subsp. paratuberculosis Recombinant Proteins for Antigen Discovery?  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease, a chronic granulomatous enteritis of ruminants and other species. Detection of infection in animals is hampered by the lack of sensitive and specific diagnostic assays. We describe here an approach that utilizes translationally active PCR fragments for the rapid in vitro transcription and translation of recombinant proteins for antigen discovery in M. avium subsp. paratuberculosis. The investigations showed that the MAP1272c protein selectively reacts with sera from Johne's disease-positive cattle and represents an antigen of potential utility in M. avium subsp. paratuberculosis immunodiagnostics. PMID:17079432

Li, Lingling; Munir, Shirin; Bannantine, John P.; Sreevatsan, Srinand; Kanjilal, Sagarika; Kapur, Vivek

2007-01-01

167

Stability evaluation of freeze-dried Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules  

PubMed Central

Freeze-drying is a common preservation technology in the pharmaceutical industry. Various studies have investigated the effect of different cryoprotectants on probiotics during freeze-drying. However, information on the effect of cryoprotectants on the stability of some Lactobacillus strains during freeze-drying seems scarce. Therefore, the aim of the present study was to establish production methods for preparation of oral capsule probiotics containing Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. Bulgaricus. It was also of interest to examine the effect of various formulations of cryoprotectant media containing skim milk, trehalose and sodium ascorbate on the survival rate of probiotic bacteria during freeze-drying at various storage temperatures. Without any cryoprotectant, few numbers of microorganisms survived. However, microorganisms tested maintained higher viability after freeze-drying in media containing at least one of the cryoprotectants. Use of skim milk in water resulted in an increased viability after lyophilization. Media with a combination of trehalose and skim milk maintained a higher percentage of live microorganisms, up to 82%. In general, bacteria retained a higher number of viable cells in capsules containing freeze-dried bacteria with sodium ascorbate after three months of storage. After this period, a marked decline was observed in all samples stored at 23°C compared to those stored at 4°C. The maximum survival rate (about 72-76%) was observed with media containing 6% skim milk, 8% trehalose and 4% sodium ascorbate. PMID:23181077

Jalali, M.; Abedi, D.; Varshosaz, J.; Najjarzadeh, M.; Mirlohi, M.; Tavakoli, N.

2012-01-01

168

A comparative study of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. hominissuis in experimentally infected pigs  

PubMed Central

Background Mycobacterium avium subsp. avium (Maa) and Mycobacterium avium subsp. hominissuis (Mah) are opportunistic pathogens that may infect several species, including humans and pigs. Mah is however more frequently isolated from pigs than Maa, and it is unclear if this is due to difference in virulence or in exposure to the two organisms. Clinical isolates of each subspecies were administered perorally to ten domestic pigs, respectively. The animals were sacrificed at six and 12 weeks after inoculation. At necropsy, macroscopic lesions were recorded, and tissue samples were collected for mycobacterial culture, IS1245 real time PCR and histopathological examination. Culturing was also performed on faecal samples collected at necropsy. Results Macroscopic and histopathological lesions were detected in pigs infected with each subspecies, and bacterial growth and histopathological changes were demonstrated, also in samples from organs without gross pathological lesions. Six weeks after inoculation, live Mah was detected in faeces, as opposed to Maa. The presence of live mycobacteria was also more pronounced in Mah infected tonsils. In comparison, the Maa isolate appeared to have a higher ability of intracellular replication in porcine macrophages compared to the Mah isolate. Conclusions The study shows that both subspecies were able to infect pigs. Additionally, the more extensive shedding of Mah might cause pig-to-pig transmission and contribute to the higher incidence of infection caused by this subspecies. PMID:22284630

2012-01-01

169

Leaf traits, shoot growth and seed production in mature Fagus sylvatica trees after 8 years of CO2 enrichment  

PubMed Central

Background and Aims Masting, i.e. synchronous but highly variable interannual seed production, is a strong sink for carbon and nutrients. It may, therefore, compete with vegetative growth. It is currently unknown whether increased atmospheric CO2 concentrations will affect the carbon balance (or that of other nutrients) between reproduction and vegetative growth of forest species. In this study, reproduction and vegetative growth of shoots of mature beech (Fagus sylvatica) trees grown at ambient and elevated atmospheric CO2 concentrations were quantified. It was hypothesized that within a shoot, fruiting has a negative effect on vegetative growth, and that this effect is ameliorated at increased CO2 concentrations. Methods Reproduction and its competition with leaf and shoot production were examined during two masting events (in 2007 and 2009) in F. sylvatica trees that had been exposed to either ambient or elevated CO2 concentrations (530 µmol mol?1) for eight consecutive years, between 2000 and 2008. Key Results The number of leaves per shoot and the length of terminal shoots was smaller or shorter in the two masting years compared with the one non-masting year (2008) investigated, but they were unaffected by elevated CO2 concentrations. The dry mass of terminal shoots was approx. 2-fold lower in the masting year (2007) than in the non-masting year in trees growing at ambient CO2 concentrations, but this decline was not observed in trees exposed to elevated CO2 concentrations. In both the CO2 treatments, fruiting significantly decreased nitrogen concentration by 25 % in leaves and xylem tissue of 1- to 3-year-old branches in 2009. Conclusions Our findings indicate that there is competition for resources between reproduction and shoot growth. Elevated CO2 concentrations reduced this competition, indicating effects on the balance of resource allocation between reproduction and vegetative growth in shoots with rising atmospheric CO2 concentrations. PMID:21493641

Han, Qingmin; Kabeya, Daisuke; Hoch, Günter

2011-01-01

170

Comparison of pollen gene flow among four European beech (Fagus sylvatica L.) populations characterized by different management regimes  

PubMed Central

The study of the dispersal capability of a species can provide essential information for the management and conservation of its genetic variability. Comparison of gene flow rates among populations characterized by different management and evolutionary histories allows one to decipher the role of factors such as isolation and tree density on gene movements. We used two paternity analysis approaches and different strategies to handle the possible presence of genotyping errors to obtain robust estimates of pollen flow in four European beech (Fagus sylvatica L.) populations from Austria and France. In each country one of the two plots is located in an unmanaged forest; the other plots are managed with a shelterwood system and inside a colonization area (in Austria and France, respectively). The two paternity analysis approaches provided almost identical estimates of gene flow. In general, we found high pollen immigration (?75% of pollen from outside), with the exception of the plot from a highly isolated forest remnant (?50%). In the two unmanaged plots, the average within-population pollen dispersal distances (from 80 to 184?m) were higher than previously estimated for beech. From the comparison between the Austrian managed and unmanaged plots, that are only 500?m apart, we found no evidence that either gene flow or reproductive success distributions were significantly altered by forest management. The investigated phenotypic traits (crown area, height, diameter and flowering phenology) were not significantly related with male reproductive success. Shelterwood seems to have an effect on the distribution of within-population pollen dispersal distances. In the managed plot, pollen dispersal distances were shorter, possibly because adult tree density is three-fold (163 versus 57 trees per hectare) with respect to the unmanaged one. PMID:21897442

Piotti, A; Leonardi, S; Buiteveld, J; Geburek, T; Gerber, S; Kramer, K; Vettori, C; Vendramin, G G

2012-01-01

171

Exploring the Genome of Cheese Starter Lactic Acid Bacterium Lactococcus lactis subsp. lactis CECT 4433.  

PubMed

Here, we present the draft genome sequences of Lactococcus lactis subsp. lactis CECT 4433, a cheese fermentation starter strain. The genome provides further insight into the genomic plasticity, biocomplexity (including gene strain specifics), and evolution of these genera. PMID:25395632

Tschoeke, Diogo Antonio; Moreira, Ana Paula B; Chimetto Tonon, Luciane A; de Mesquita, Milene Miranda A; Gregoracci, Gustavo B; Gomez-Gil, Bruno; Valle, Rogério; Thompson, Cristiane C; Thompson, Fabiano L

2014-01-01

172

Exploring the Genome of Cheese Starter Lactic Acid Bacterium Lactococcus lactis subsp. lactis CECT 4433  

PubMed Central

Here, we present the draft genome sequences of Lactococcus lactis subsp. lactis CECT 4433, a cheese fermentation starter strain. The genome provides further insight into the genomic plasticity, biocomplexity (including gene strain specifics), and evolution of these genera. PMID:25395632

Tschoeke, Diogo Antonio; Moreira, Ana Paula B.; Chimetto Tonon, Luciane A.; de Mesquita, Milene Miranda A.; Gregoracci, Gustavo B.; Gomez-Gil, Bruno; Valle, Rogério; Thompson, Cristiane C.

2014-01-01

173

Complete genome sequence of Campylobacter fetus subsp. testudinum type strain 03-427T  

Technology Transfer Automated Retrieval System (TEKTRAN)

Campylobacter fetus subsp. testudinum has been isolated from reptiles and humans. This Campylobacter subspecies is genetically distinct from other C. fetus subspecies. Here we present the first whole genome sequence for this C. fetus subspecies....

174

Lactococcus lactis subsp. lactis infection in waterfowl: first confirmation in animals.  

PubMed Central

We report the first description, confirmed by bacteriologic and molecular (polymerase chain reaction and pulsed-field gel electrophoresis) analysis, of an infection in animals caused by Lactococcus lactis subsp. lactis, affecting waterfowl. PMID:11747704

Goyache, J.; Vela, A. I.; Gibello, A.; Blanco, M. M.; Briones, V.; González, S.; Téllez, S.; Ballesteros, C.; Domínguez, L.; Fernández-Garayzábal, J. F.

2001-01-01

175

Molecular characterization of three Lactobacillus delbrueckii subsp. bulgaricus phages.  

PubMed

In this study, three phages infecting Lactobacillus delbrueckii subsp. bulgaricus, named Ld3, Ld17, and Ld25A, were isolated from whey samples obtained from various industrial fermentations. These phages were further characterized in a multifaceted approach: (i) biological and physical characterization through host range analysis and electron microscopy; (ii) genetic assessment through genome analysis; (iii) mass spectrometry analysis of the structural components of the phages; and (iv), for one phage, transcriptional analysis by Northern hybridization, reverse transcription-PCR, and primer extension. The three obtained phage genomes display high levels of sequence identity to each other and to genomes of the so-called group b L. delbrueckii phages c5, LL-Ku, and phiLdb, where some of the observed differences are believed to be responsible for host range variations. PMID:25002431

Casey, Eoghan; Mahony, Jennifer; O'Connell-Motherway, Mary; Bottacini, Francesca; Cornelissen, Anneleen; Neve, Horst; Heller, Knut J; Noben, Jean-Paul; Dal Bello, Fabio; van Sinderen, Douwe

2014-09-01

176

Bibenzyls and dihydroisocoumarins from white salsify (Tragopogon porrifolius subsp. porrifolius).  

PubMed

A phytochemical investigation of three accessions of Tragopogon porrifolius L. subsp. porrifolius (Asteraceae, Lactuceae) yielded three new bibenzyl derivatives, 5,4'-dihydroxy-3-alpha-l-rhamnopyranosyl-(1-->3)-beta-d-xylopyranosyloxybibenzyl, 2-carboxyl-3,4'-dihydroxy-5-beta-d-xylopyranosyloxybibenzyl, tragopogonic acid (2'carboxyl-3',5',4''-trihydroxyphenylethanone) and three dihydroisocoumarin derivatives, including the new natural product 6-O-methylscorzocreticoside I. One of the isolated bibenzyl derivatives is considered to be a precursor to the biosynthesis of dihydroisocoumarins. Structures of new compounds were established by HR mass spectrometry, extensive 1D and 2D NMR spectroscopy, and CD spectroscopy. Moreover, radical scavenging activities of the polyphenolic compounds were measured using the 2,2-diphenyl-1-picrylhydrazyl assay; two of the bibenzyls showed moderate and two of the dihydroisocoumarins showed weak radical scavenging activities. The chemosystematic impact of bibenzyls and dihydroisocoumarins is discussed briefly. PMID:15964041

Zidorn, Christian; Lohwasser, Ulrike; Pschorr, Susanne; Salvenmoser, Daniela; Ongania, Karl-Hans; Ellmerer, Ernst P; Börner, Andreas; Stuppner, Hermann

2005-07-01

177

Sources and distribution of Campylobacter fetus subsp. jejuni in turkeys  

E-print Network

(NPN) procedure. C. fetus subsp. jejuni PAR 6 inoculated into and recovered from turke e sa 0 E F G H I Initial concentration (per ml) 10, 000 5, 000 1, 000 500 100 50 10 5 1 Egg-Brucella-FBP Broth mixturesc + + + + + NPN per mid Upper limite... concentrationb (per ml) 54 27 6 3 0. 6 0. 3 0. 06 0. 03 0. 006 Egg-Brucella-FBP Broth mixturesc MPN per mid Upper limite Lower limite + + + + + + + 15 43 9. 3 4. 3 0. 4 1. 5 &0. 3 &0. 3 &0. 3 44 210 38 21 2 4. 4 3 7 1. 5 0. 7 &0. 05 0. 3 a50 g of eggs...

Acuff, Gary Royce

1982-01-01

178

Two antigenotoxic chalcone glycosides from Mentha longifolia subsp. longifolia.  

PubMed

Abstract Context: Mentha L. (Labiatae) species (mint) with their flavoring properties have been used in food industries for centuries. Besides they have a great importance in drug development and medicinal applications due to various bioactive compounds of several members of the genus. Objective: The aim of this study was to isolate bioactive compounds with antimutagenic potential by bio-guided fractionation and determine their structures by spectroscopic methods. Materials and methods: The structural elucidation of the isolated compounds was done based on spectroscopic methods, including MALDI-MS, UV, IR, and 2D NMR experiments, and the bio-guided fractionation process was done by using the Ames/Salmonella test system. Henceforth, solely genotoxic and antigenotoxic potential of the new compounds were also confirmed up to 2?µM/plate by using the same test system. Results: Two new chalcone glycosides: (?R)-?,3,2',6'-tetrahydroxy-4-methoxy-4'-O-rutinosyldihydrochalcone and (?R)-?,4,2',6'-tetrahydroxy-4'-O-rutinosyldihydrochalcone, were isolated from Mentha longifolia (L.) Hudson subsp. longifolia, together with known six flavonoid glycosides and one phenolic acid: apigenin-7-O-glucoside, luteolin-7-O-glucoside, apigenin-7-O-rutinoside, luteolin-7-O-rutinoside, apigenin-7-O-glucuronide, luteolin-7-O-glucuronide, rosmarinic acid. According to the antimutagenicity results, both new test compounds significantly inhibited the mutagenic activity of 9-aminoacridine in a dose-dependent manner at the tested concentrations from 0.8 to 2?µM/plate. (?R)-?,4,2',6'-Tetrahydroxy-4'-O-rutinosyldihydrochalcone showed the maximum inhibition rate as 75.94% at 2?µM/plate concentration. Conclusions: This is the first report that two new chalcone glycosides were isolated from Mentha longifolia subsp. longifolia and their antimutagenic potentials by using mutant bacterial tester strains. In conclusion, the two new chalcone glycosides showed a significant antigenotoxic effect on 9-aminoacridine-induced mutagenesis at tested concentrations. PMID:25429992

Guvenalp, Zuhal; Ozbek, Hilal; Karadayi, Mehmet; Gulluce, Medine; Kuruuzum-Uz, Ayse; Salih, Bekir; Demirezer, Omur

2014-11-28

179

Occurrence of Mycobacterium avium subsp. paratuberculosis in untreated water in Northern Ireland.  

PubMed

Mycobacterium avium subsp. paratuberculosis is the known cause of Johne's disease of both domestic and wild ruminants and has been implicated as a possible cause of Crohn's disease in humans. The organism is shed in the feces of infected animals and can survive for protracted periods in the environment and hence could be present in catchment areas receiving agricultural runoff. A limited survey was undertaken in Northern Ireland to test for M. avium subsp. paratuberculosis in untreated water entering nine water treatment works (WTWs) over a 1-year period. Three detection methods were employed, viz., immunomagnetic separation-PCR and culture on Herrold's egg yolk medium (HEYM) and BACTEC 12B medium, the latter both supplemented with mycobactins. Of the 192 untreated water samples tested, 15 (8%) tested M. avium subsp. paratuberculosis positive by one or more of the three detection methods. M. avium subsp. paratuberculosis was successfully isolated from eight untreated water samples, three by BACTEC culture and five by culture on HEYM. Although the highest incidence of M. avium subsp. paratuberculosis was found in spring, overall, there was no statistically significant difference between the seasons. No significant correlation was found between numbers of coliforms or fecal coliforms and the presence of M. avium subsp. paratuberculosis. In general, a higher incidence of M. avium subsp. paratuberculosis was found in untreated water entering those WTWs that had a high mean water pH value over the sampling period. This work indicates the need to determine the efficacy of water treatment processes to either kill or remove M. avium subsp. paratuberculosis from untreated water and the possible risks posed by contact with recreational water sources. PMID:16269747

Whan, Lynne; Ball, Hywel J; Grant, Irene R; Rowe, Michael T

2005-11-01

180

Determination of kinetic properties of polyphenol oxidase from Thymus ( Thymus longicaulis subsp. chaubardii var. chaubardii)  

Microsoft Academic Search

A partial characterization of polyphenol oxidase (PPO) activity of Thymus longicaulis subsp. chaubardii var. chaubardii is described. Polyphenol oxidase of Thymus was isolated by (NH4)2SO4 precipitation and dialysis. The effects of substrate specificity, pH, temperature, heat-inactivation and glutathione inhibitor on polyphenol oxidase activity obtained from T. longicaulis subsp. chaubardii var. chaubardii were investigated. Polyphenol oxidase showed activity toward catechol, 4-methylcatechol

Serap Dogan; Mehmet Dogan

2004-01-01

181

Seed-associated subspecies of the genus Clavibacter are clearly distinguishable from Clavibacter michiganensis subsp. michiganensis.  

PubMed

The genus Clavibacter contains one recognized species, Clavibacter michiganensis. Clavibacter michiganensis is subdivided into subspecies based on host specificity and bacteriological characteristics, with Clavibacter michiganensis subsp. michiganensis causing bacterial canker of tomato. Clavibacter michiganensis subsp. michiganensis is often spread through contaminated seed leading to outbreaks of bacterial canker in tomato production areas worldwide. The frequent occurrence of non-pathogenic Clavibacter michiganensis subsp. michiganensis-like bacteria (CMB) is a concern for seed producers because Clavibacter michiganensis subsp. michiganensis is a quarantine organism and detection of a non-pathogenic variant may result in destruction of an otherwise healthy seed lot. A thorough biological and genetic characterization of these seed-associated CMB strains was performed using standard biochemical tests, cell wall analyses, metabolic profiling using Biolog, and single-gene and multilocus sequence analyses. Combined, these tests revealed two distinct populations of seed-associated members of the genus Clavibacter that differed from each other, as well as from all other described subspecies of Clavibacter michiganensis. DNA-DNA hybridization values are 70?% or higher, justifying placement into the single recognized species, C. michiganensis, but other analyses justify separate subspecies designations. Additionally, strains belonging to the genus Clavibacter isolated from pepper also represent a distinct population and warrant separate subspecies designation. On the basis of these data we propose subspecies designations for separate non-pathogenic subpopulations of Clavibacter michiganensis: Clavibacter michiganensis subsp. californiensis subsp. nov. and Clavibacter michiganensis subsp. chilensis subsp. nov. for seed-associated strains represented by C55(T) (?=?ATCC BAA-2691(T)?=?CFBP 8216(T)) and ZUM3936(T) (?=?ATCC BAA-2690(T)?=?CFBP 8217(T)), respectively. Recognition of separate subspecies is essential for improved international seed testing operations. PMID:25481293

Yasuhara-Bell, Jarred; Alvarez, Anne M

2015-03-01

182

Local evolution of obligate autogamy in Epipactis helleborine subsp. neerlandica (Orchidaceae)  

Microsoft Academic Search

Isozyme analysis was used to assess the origin of the DanishEpipactis renzii, a local endemic of open coastal dunes. It seems to have evolved recently in several local populations of the more or less allogamousE. helleborine subsp.neerlandica. The obligately autogamousE. renzii is restricted to the easternmost part of the Danish range ofE. helleborine subsp.neerlandica, indicating that transition to obligate autogamy

H. Æ. Pedersen; B. K. Ehlers

2000-01-01

183

Morphological variation of Medicago sativa subsp. falcata genotypes and their hybrid progeny  

Microsoft Academic Search

Semi-hybrid alfalfa cultivars offer the possibility of capturing non-additive genetic variation. Medicago sativa subsp. falcata and subsp.sativa have been shown to form a heterotic pattern for biomass yield. Objectives of this study were to examine morphological variation\\u000a in a broad range of falcate germplasm and to determine how falcate morphological variation per se is related to the performance of falcate

Heathcliffe Riday; E. Charles Brummer

2004-01-01

184

Alfalfa Subsp. Sativa by Falcata Intersubspecific Semi-Hybrid Seed Production Using Alfalfa Leafcutter Bees  

Microsoft Academic Search

Intersubspecific sativa by falcata alfalfa (Medicago sativa L.) hybrids offer a means of improving alfalfa dry-matter yields. The alfalfa leafcutter bee (Megachile rotundata F.) is a major pollinator used in alfalfa seed production in North America. Alfalfa leafcutter bees have a pollinator preference for purple-flowered subsp. sativa plants over the yellow-flowered subsp. falcata plants. This study was conducted to quantify

Heathcliffe Riday

2008-01-01

185

Occurrence of Mycobacterium avium subsp. paratuberculosis in Untreated Water in Northern Ireland  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is the known cause of Johne's disease of both domestic and wild ruminants and has been implicated as a possible cause of Crohn's disease in humans. The organism is shed in the feces of infected animals and can survive for protracted periods in the environment and hence could be present in catchment areas receiving agricultural runoff. A limited survey was undertaken in Northern Ireland to test for M. avium subsp. paratuberculosis in untreated water entering nine water treatment works (WTWs) over a 1-year period. Three detection methods were employed, viz., immunomagnetic separation-PCR and culture on Herrold's egg yolk medium (HEYM) and BACTEC 12B medium, the latter both supplemented with mycobactins. Of the 192 untreated water samples tested, 15 (8%) tested M. avium subsp. paratuberculosis positive by one or more of the three detection methods. M. avium subsp. paratuberculosis was successfully isolated from eight untreated water samples, three by BACTEC culture and five by culture on HEYM. Although the highest incidence of M. avium subsp. paratuberculosis was found in spring, overall, there was no statistically significant difference between the seasons. No significant correlation was found between numbers of coliforms or fecal coliforms and the presence of M. avium subsp. paratuberculosis. In general, a higher incidence of M. avium subsp. paratuberculosis was found in untreated water entering those WTWs that had a high mean water pH value over the sampling period. This work indicates the need to determine the efficacy of water treatment processes to either kill or remove M. avium subsp. paratuberculosis from untreated water and the possible risks posed by contact with recreational water sources. PMID:16269747

Whan, Lynne; Ball, Hywel J.; Grant, Irene R.; Rowe, Michael T.

2005-01-01

186

Maximizing Capture Efficiency and Specificity of Magnetic Separation for Mycobacterium avium subsp. paratuberculosis Cells ?  

PubMed Central

In order to introduce specificity for Mycobacterium avium subsp. paratuberculosis prior to a phage amplification assay, various magnetic-separation approaches, involving either antibodies or peptides, were evaluated in terms of the efficiency of capture (expressed as a percentage) of M. avium subsp. paratuberculosis cells and the percentage of nonspecific binding by other Mycobacterium spp. A 50:50 mixture of MyOne Tosylactivated Dynabeads coated with the chemically synthesized M. avium subsp. paratuberculosis-specific peptides biotinylated aMp3 and biotinylated aMptD (i.e., peptide-mediated magnetic separation [PMS]) proved to be the best magnetic-separation approach for achieving 85 to 100% capture of M. avium subsp. paratuberculosis and minimal (<1%) nonspecific recovery of other Mycobacterium spp. (particularly if beads were blocked with 1% skim milk before use) from broth samples containing 103 to 104 CFU/ml. When PMS was coupled with a recently optimized phage amplification assay and used to detect M. avium subsp. paratuberculosis in 50-ml volumes of spiked milk, the mean 50% limit of detection (LOD50) was 14.4 PFU/50 ml of milk (equivalent to 0.3 PFU/ml). This PMS-phage assay represents a novel, rapid method for the detection and enumeration of viable M. avium subsp. paratuberculosis organisms in milk, and potentially other sample matrices, with results available within 48 h. PMID:20851966

Foddai, Antonio; Elliott, Christopher T.; Grant, Irene R.

2010-01-01

187

Characterization of Pneumonia Due to Streptococcus equi subsp. zooepidemicus in Dogs?  

PubMed Central

Streptococcus equi subsp. zooepidemicus has been linked to cases of acute fatal pneumonia in dogs in several countries. Outbreaks can occur in kenneled dog populations and result in significant levels of morbidity and mortality. This highly contagious disease is characterized by the sudden onset of clinical signs, including pyrexia, dyspnea, and hemorrhagic nasal discharge. The pathogenesis of S. equi subsp. zooepidemicus infection in dogs is poorly understood. This study systematically characterized the histopathological changes in the lungs of 39 dogs from a large rehoming shelter in London, United Kingdom; the dogs were infected with S. equi subsp. zooepidemicus. An objective scoring system demonstrated that S. equi subsp. zooepidemicus caused pneumonia in 26/39 (66.7%) dogs, and most of these dogs (17/26 [65.4%]) were classified as severe fibrino-suppurative, necrotizing, and hemorrhagic. Three recently described superantigen genes (szeF, szeN, and szeP) were detected by PCR in 17/47 (36.2%) of the S. equi subsp. zooepidemicus isolates; however, there was no association between the presence of these genes and the histopathological score. The lungs of S. equi subsp. zooepidemicus-infected dogs with severe respiratory signs and lung pathology did however have significantly higher mRNA levels of the proinflammatory cytokines tumor necrosis factor alpha (TNF-?), interleukin 6 (IL-6), and interleukin 8 (IL-8) than in uninfected controls, suggesting a role for an exuberant host immune response in the pathogenesis of this disease. PMID:20861329

Priestnall, Simon L.; Erles, Kerstin; Brooks, Harriet W.; Cardwell, Jacqueline M.; Waller, Andrew S.; Paillot, Romain; Robinson, Carl; Darby, Alistair C.; Holden, Matthew T. G.; Schöniger, Sandra

2010-01-01

188

GA(3)-induced expression of a new functional AAA-ATPase (FsA1) is correlated with the onset of germination in Fagus sylvatica L. seeds (beechnuts).  

PubMed

A full-length cDNA clone, named FsA1, has been isolated from a cDNA library constructed using mRNA from Fagus sylvatica L. dormant seeds (beechnuts). This clone shows high identity with members of the AAA superfamily, for ATPases Associated with a variety of cellular Activities, encoding subunit 8 of the 26S proteasome or Tat binding proteins (TBPs). Direct biochemical evidence supporting Mg(2+)-dependent ATPase activity has been obtained by expressing FsA1 in Escherichia coli as histidine tag fusion protein and using the recombinant protein in the stimulation of ATP hydrolysis. Analysis of the expression of FsA1 transcripts during stratification shows an increase in the presence of gibberellic acid (GA(3)), a treatment that proved to be efficient in breaking dormancy and increasing germination percentages of these seeds, while the addition of paclobutrazol, a well-known GA biosynthesis inhibitor, greatly reduces the expression of the clone. A low level of expression was maintained in the stratification control in H(2)O, where dormancy is slowly released. These results show that this new member of the AAA-ATPase family is up-regulated by GAs and its expression correlated with the germination arise in Fagus sylvatica seeds. The possible function of this protein during the transition from dormancy to germination is discussed. PMID:11828019

Lorenzo, Oscar; Nicolás, Carlos; Nicolás, Gregorio; Rodríguez, Dolores

2002-01-01

189

Tree-ring stable isotopes reveal twentieth-century increases in water-use efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean mountains.  

PubMed

Changes in intrinsic water use efficiency (iWUE) were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI) along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in ?13C, ?13C, ?18O, Ci (internal CO2 concentration), iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration) and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, ?13C and ?18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and ?13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations. PMID:25398040

Tognetti, Roberto; Lombardi, Fabio; Lasserre, Bruno; Cherubini, Paolo; Marchetti, Marco

2014-01-01

190

Tree-Ring Stable Isotopes Reveal Twentieth-Century Increases in Water-Use Efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean Mountains  

PubMed Central

Changes in intrinsic water use efficiency (iWUE) were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI) along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in ?13C, ?13C, ?18O, Ci (internal CO2 concentration), iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration) and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, ?13C and ?18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and ?13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations. PMID:25398040

Tognetti, Roberto; Lombardi, Fabio; Lasserre, Bruno; Cherubini, Paolo; Marchetti, Marco

2014-01-01

191

What are the functional mechanisms underlying forest decline? A case study on a European beech (Fagus sylvatica L.) stand.  

NASA Astrophysics Data System (ADS)

The ongoing climate change is altering the precipitation patterns (abundance and frequency) of most parts of the world. The consequences of these changes on forests are already visible through frequent declines. A lot of them can be linked to the occurrence of long and/or repeated drought periods. Although forest decline could severely impact the nutrient and water cycles, their underlying functional causes are not well understood. Two main hypotheses have been proposed to explain the mechanisms of decline at the tree level: • Carbon reserves deficit ("carbon starvation") • Loss of water transport ( "hydraulic failure") Although hydraulic failure has been observed in a wetland species decline (poplar), our understanding of forest decline is still lacking in many species. Our study concerns a widespread species, European beech (Fagus sylvatica L.). A severely declining mature beech plot in the Fontainebleau state forest (France) was followed. This decline can be related to repeated droughts, enhanced by unfavorable soil conditions (sandy soil with very low extractible soil water). For the first time to our knowledge, an integrative in situ functional approach coupling both hydraulic and carbon, but also nitrogen functioning was developed. More precisely, pre-dawn and midday water potentials, "native" embolism, and embolism vulnerability of branches, radial tree growth, carbon and nitrogen reserves concentrations, were measured on healthy and declining trees. Our results showed that under normal climatic conditions (summer 2012), pre-dawn and midday water potentials were the same for healthy and declining trees throughout the season. Their losses of hydraulic conductivity ("native" embolism) were not significantly different, even at the end of the summer. Moreover, the embolism vulnerability curves also showed no significant difference (50% loss of hydraulic conductivity at around - 3MPa). Concerning C and N reserves concentrations, we showed that seasonal variations were the same for healthy and declining trees. However, starch concentration was significantly lower before budburst in 2010 growth units and recent xylem rings in declining trees. These deficits in short distance storage compartments could lead to an altered spring growth. Indeed, radial growth rate and duration were drastically lower for declining trees. Finally, the observed beech decline cannot be attributed to either hydraulic dysfunction or nitrogen starvation. Concerning carbon functioning, the carbon reserves of declining trees were far from being exhausted. Despite a lower net carbon assimilation at the tree level (reduced leaf area index), trees maintain similar carbon and nitrogen reserves content, radial growth being apparently the adjusted variable.

Delaporte, Alice; Bazot, Stéphane; Fresneau, Chantal; Damesin, Claire

2013-04-01

192

Influence of litter chemistry and stoichiometry on glucan depolymerization during decomposition of beech (Fagus sylvatica L.) litter  

PubMed Central

Glucans like cellulose and starch are a major source of carbon for decomposer food webs, especially during early- and intermediate-stages of decomposition. Litter quality has previously been suggested to notably influence decomposition processes as it determines the decomposability of organic material and the nutrient availability to the decomposer community. To study the impact of chemical and elemental composition of resources on glucan decomposition, a laboratory experiment was carried out using beech (Fagus sylvatica, L.) litter from four different locations in Austria, differing in composition (concentration of starch, cellulose and acid unhydrolyzable residue or AUR fraction) and elemental stoichiometry (C:N:P ratio). Leaf litter was incubated in mesocosms for six months in the laboratory under controlled conditions. To investigate the process of glucan decomposition and its controls, we developed an isotope pool dilution (IPD) assay using 13C-glucose to label the pool of free glucose in the litter, and subsequently measured the dilution of label over time. This enabled us to calculate gross rates of glucose production through glucan depolymerization, and glucose consumption by the microbial community. In addition, potential activities of extracellular cellulases and ligninases (peroxidases and phenoloxidases) were measured to identify effects of resource chemistry and stoichiometry on microbial enzyme production. Gross rates of glucan depolymerization and glucose consumption were highly correlated, indicating that both processes are co-regulated and intrinsically linked by the microbial demand for C and energy and thereby to resource allocation to enzymes that depolymerize glucans. At early stages of decomposition, glucan depolymerization rates were correlated with starch content, indicating that starch was the primary source for glucose. With progressing litter decomposition, the correlation with starch diminished and glucan depolymerization rates were highly correlated to cellulase activities, suggesting that cellulose was the primary substrate for glucan depolymerization at this stage of decomposition. Litter stoichiometry did not affect glucan depolymerization or glucose consumption rates early in decomposition. At later stages, however, we found significant negative relationships between glucan depolymerization and litter C:N and AUR:N ratio and a positive relationship between glucan depolymerization and litter N concentration. Litter C:N and C:P ratios were negatively related to cellulase, peroxidase and phenoloxidase activities three and six months after incubation, further corroborating the importance of resource stoichiometry for glucan depolymerization after the initial pulse of starch degradation. PMID:22761539

Leitner, Sonja; Wanek, Wolfgang; Wild, Birgit; Haemmerle, Ieda; Kohl, Lukas; Keiblinger, Katharina M.; Zechmeister-Boltenstern, Sophie; Richter, Andreas

2012-01-01

193

Bifidobacterium animalis subsp. lactis ATCC 27673 Is a Genomically Unique Strain within Its Conserved Subspecies  

PubMed Central

Many strains of Bifidobacterium animalis subsp. lactis are considered health-promoting probiotic microorganisms and are commonly formulated into fermented dairy foods. Analyses of previously sequenced genomes of B. animalis subsp. lactis have revealed little genetic diversity, suggesting that it is a monomorphic subspecies. However, during a multilocus sequence typing survey of Bifidobacterium, it was revealed that B. animalis subsp. lactis ATCC 27673 gave a profile distinct from that of the other strains of the subspecies. As part of an ongoing study designed to understand the genetic diversity of this subspecies, the genome of this strain was sequenced and compared to other sequenced genomes of B. animalis subsp. lactis and B. animalis subsp. animalis. The complete genome of ATCC 27673 was 1,963,012 bp, contained 1,616 genes and 4 rRNA operons, and had a G+C content of 61.55%. Comparative analyses revealed that the genome of ATCC 27673 contained six distinct genomic islands encoding 83 open reading frames not found in other strains of the same subspecies. In four islands, either phage or mobile genetic elements were identified. In island 6, a novel clustered regularly interspaced short palindromic repeat (CRISPR) locus which contained 81 unique spacers was identified. This type I-E CRISPR-cas system differs from the type I-C systems previously identified in this subspecies, representing the first identification of a different system in B. animalis subsp. lactis. This study revealed that ATCC 27673 is a strain of B. animalis subsp. lactis with novel genetic content and suggests that the lack of genetic variability observed is likely due to the repeated sequencing of a limited number of widely distributed commercial strains. PMID:23995933

Loquasto, Joseph R.; Barrangou, Rodolphe; Dudley, Edward G.; Stahl, Buffy; Chen, Chun

2013-01-01

194

Versatile use of oriC plasmids for functional genomics of Mycoplasma capricolum subsp. capricolum.  

PubMed

Replicative oriC plasmids were recently developed for several mollicutes, including three Mycoplasma species belonging to the mycoides cluster that are responsible for bovine and caprine diseases: Mycoplasma mycoides subsp. mycoides small-colony type, Mycoplasma mycoides subsp. mycoides large-colony type, and Mycoplasma capricolum subsp. capricolum. In this study, oriC plasmids were evaluated in M. capricolum subsp. capricolum as genetic tools for (i) expression of heterologous proteins and (ii) gene inactivation by homologous recombination. The reporter gene lacZ, encoding beta-galactosidase, and the gene encoding spiralin, an abundant surface lipoprotein of the related mollicute Spiroplasma citri, were successfully expressed. Functional Escherichia coli beta-galactosidase was detected in transformed Mycoplasma capricolum subsp. capricolum cells despite noticeable codon usage differences. The expression of spiralin in M. capricolum subsp. capricolum was assessed by colony and Western blotting. Accessibility of this protein at the cell surface and its partition into the Triton X-114 detergent phase suggest a correct maturation of the spiralin precursor. The expression of a heterologous lipoprotein in a mycoplasma raises potentially interesting applications, e.g., the use of these bacteria as live vaccines. Targeted inactivation of gene lppA encoding lipoprotein A was achieved in M. capricolum subsp. capricolum with plasmids harboring a replication origin derived from S. citri. Our results suggest that the selection of the infrequent events of homologous recombination could be enhanced by the use of oriC plasmids derived from related mollicute species. Mycoplasma gene inactivation opens the way to functional genomics in a group of bacteria for which a large wealth of genome data are already available and steadily growing. PMID:15932982

Janis, Carole; Lartigue, Carole; Frey, Joachim; Wróblewski, Henri; Thiaucourt, François; Blanchard, Alain; Sirand-Pugnet, Pascal

2005-06-01

195

Stability of the delta-endotoxin gene from Bacillus thuringiensis subsp. kurstaki in a recombinant strain of Clavibacter xyli subsp. cynodontis.  

PubMed Central

Deletion of chromosomally inserted gene sequences from Clavibacter xyli subsp. cynodontis, a xylem-inhabiting endophyte, was studied in vitro and in planta. We found that nonreplicating plasmid pCG610, which conferred resistance to kanamycin and tetracycline and contained segments of C. xyli subsp. cynodontis genomic DNA, integrated into a homologous sequence in the bacterial chromosome. In addition, pCG610 contains two copies of the gene encoding the CryIA(c) insecticidal protein of Bacillus thuringiensis subsp. kurstaki HD73. Using drug resistance phenotypes and specific DNA probes, we found that the loss of all three genes arose both in vitro under nonselective conditions and in planta. The resulting segregants are probably formed by recombination between the repeated DNA sequences flanking pCG610 that resulted from the integration event into the chromosome. Eventually, segregants predominated in the bacterial population. The loss of the integrated plasmid from C. xyli subsp. cynodontis revealed a possible approach for decreasing the environmental consequences of recombinant bacteria for agricultural use. Images PMID:1664710

Turner, J T; Lampel, J S; Stearman, R S; Sundin, G W; Gunyuzlu, P; Anderson, J J

1991-01-01

196

Quick detection of Leifsonia xyli subsp. xyli by PCR and necleotide sequence analysis of PCR amplicons from Chinese Leifsonia xyli subsp. xyli isolates  

Technology Transfer Automated Retrieval System (TEKTRAN)

A quick polymerase chain reaction (PCR) assay was developed for the detection of Leifsonia xyli subsp. xyli (Lxx), the bacterial causal agent of ratoon stunting disease (RSD) of sugarcane, in crude juice samples from stalks. After removal of abiotic impurities and large molecular weight microorgani...

197

Flow Cytometric Detection of Mycobacterium avium subsp. paratuberculosis-Specific Antibodies in Experimentally Infected and Naturally Exposed Calves  

PubMed Central

A desirable test to diagnose infections with Mycobacterium avium subsp. paratuberculosis facilitates identification of infected cattle prior to the state of M. avium subsp. paratuberculosis shedding. This study aimed at adjusting a flow cytometry (FC)-based assay, using intact M. avium subsp. paratuberculosis bacteria as the antigen, for diagnosis of M. avium subsp. paratuberculosis infections in calves. Serum samples were collected from experimentally infected (n = 12) and naturally exposed (n = 32) calves. Samples from five calves from positive dams were analyzed to determine the dynamics of maternal antibodies. Samples from adult cattle with defined infection status served as the standard (18 M. avium subsp. paratuberculosis shedders, 22 M. avium subsp. paratuberculosis free). After preadsorption with Mycobacterium phlei, sera were incubated with M. avium subsp. paratuberculosis and M. avium subsp. avium bacterial suspensions, respectively, followed by the separate detection of bovine IgG, IgG1, IgG2, and IgM attached to the bacterial surface. M. avium subsp. paratuberculosis-specific sample/positive (S/P) ratios were compared to enzyme-linked immunosorbent assay (ELISA) S/P ratios. In adult cattle, the FC assay for IgG1 had a sensitivity of 78% at a specificity of 100%. Maternally acquired antibodies could be detected in calves up to 121 days of life. While all but two sera taken at day 100 ± 10 postnatum from naturally exposed calves tested negative, elevated S/P ratios (IgG and IgG1) became detectable from 44 and 46 weeks postinoculation onwards in two calves infected experimentally. Even with the optimized FC assay, M. avium subsp. paratuberculosis-specific antibodies can only occasionally be detected in infected calves less than 12 months of age. The failure to detect such antibodies apparently reflects the distinct immunobiology of M. avium subsp. paratuberculosis infections rather than methodological constraints. PMID:23885032

Bridger, P. S.; Bulun, H.; Fischer, M.; Akineden, Ö.; Seeger, T.; Barth, S.; Henrich, M.; Doll, K.; Bülte, M.; Menge, C.; Bauerfeind, R.

2013-01-01

198

IDENTIFICATION OF GENOMIC DIFFERENCES BETWEEN CAMPYLOBACTER JEJUNI SUBSP. JEJUNI AND CAMPYLOBACTER JEJUNI SUBSP. DOYLEI AT THE NAP LOCUS LEADS TO THE DEVELOPMENT OF A C. JEJUNI SUBSPECIATION MULTIPLEX PCR METHOD  

Technology Transfer Automated Retrieval System (TEKTRAN)

The human bacterial pathogen Campylobacter jejuni contains two subspecies: C. jejuni subsp. jejuni (Cjj) and C. jejuni subsp. doylei (Cjd). Although Cjd strains are isolated infrequently in many parts of the world, they are obtained primarily from human clinical samples and result in an unusual cli...

199

Quantification of the Sensitivity of Mycobacterium avium subsp paratuberculosis and Salmonella enterica subsp enterica to Low pH and High Organic Acids using Propidium Monoazide and Quantitative PCR  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp paratuberculosis (Map) and Salmonella enterica subsp enterica (S. enterica) are two pathogens that are a concern to food and animal safety due to their ability to withstand harsh conditions encountered in the natural environment and within the host during pathogenesis. Acid...

200

Description of a Novel Adhesin of Mycobacterium avium Subsp. paratuberculosis  

PubMed Central

The binding and ingestion of Mycobacterium avium subsp. paratuberculosis (MAP) by host cells are fibronectin (FN) dependent. In several species of mycobacteria, a specific family of proteins allows the attachment and internalization of these bacteria by epithelial cells through interaction with FN. Thus, the identification of adhesion molecules is essential to understand the pathogenesis of MAP. The aim of this study was to identify and characterize FN binding cell wall proteins of MAP. We searched for conserved adhesins within a large panel of surface immunogenic proteins of MAP and investigated a possible interaction with FN. For this purpose, a cell wall protein fraction was obtained and resolved by 2D electrophoresis. The immunoreactive spots were identified by MALDI-TOF MS and a homology search was performed. We selected elongation factor Tu (EF-Tu) as candidate for further studies. We demonstrated the FN-binding capability of EF-Tu using a ligand blot assay and also confirmed the interaction with FN in a dose-dependent manner by ELISA. The dissociation constant of EF-Tu was determined by surface plasmon resonance and displayed values within the ?M range. These data support the hypothesis that this protein could be involved in the interaction of MAP with epithelial cells through FN binding. PMID:25136616

Viale, Mariana Noelia; Echeverria-Valencia, Gabriela; Romasanta, Pablo; Mon, María Laura; Fernandez, Marisa; Malchiodi, Emilio; Romano, María Isabel; Gioffré, Andrea Karina; Santangelo, María de la Paz

2014-01-01

201

Mycobacterium avium subsp. paratuberculosis in scavenging mammals in Wisconsin.  

PubMed

The presence of Mycobacterium avium subsp. paratuberculosis (MAP) in non-ruminant wildlife has raised questions regarding the role of these species in Johne's disease transmission. In this study we tested 472 tissues from 212 animals of six different species of scavenging mammals. All animals were taken from within a 210-square-mile area in Dane and Iowa counties of south central Wisconsin from September to May in 2003-04 and tested for the presence of MAP. We detected MAP-specific DNA in 81 of 212 (38%) scavenging mammals, in 98 of the 472 (21%) tissues; viable MAP was cultured from one coyote's ileum and lymph node tissue. Despite the low numbers of viable MAP isolated in this study, our data adds to the increasing evidence demonstrating the potential for transmission and infection of MAP in nonruminant species and provides possible evidence of interspecies transmission. The apparently high exposure of nonruminant wildlife provides potential evidence of a spill-over of MAP to wildlife species and raises the question of spillback to domestic and wild ruminants. These results demonstrate the importance of understanding the role of wildlife species in developing management strategies for Johne's disease in domestic livestock. PMID:17495318

Anderson, Jennifer L; Meece, Jennifer K; Koziczkowski, Jeff J; Clark, Dorn L; Radcliff, Roy P; Nolden, Cherrie A; Samuel, Michael D; Ellingson, Jay L E

2007-04-01

202

Prevalence on beef carcasses of Mycobacterium avium subsp. paratuberculosis DNA.  

PubMed

Fifty samples were collected from each of skinned and dressed carcasses, from each of culled beef breeding cows and fed beef cattle <18 months old at two beef packing plants A and B, and from culled dairy cows at a packing plant C. The 450 samples were collected by swabbing an area of about 1000 cm2 in the anal region of each carcass. DNA extracted from each swab was tested for the IS900 and F57 sequences of the Mycobacterium avium subsp. paratuberculosis (MAP) genome by two stage, nested polymerase chain reaction (PCR) procedures. An internal amplification control (IAC) was detected in 45 or more of each group of 50 DNA preparations. IS900 and F57 were detected in some IAC-positive preparations from all and all but one of the groups of carcasses, respectively. Of the IAC-positive preparations in each group, between 6 and 54% were positive for IS900, and between 4 and 20% were positive for F57. When preparations were tested by single stage, quantitative PCR procedures, IS900 was detected in two samples but F57 was detected in none. The MAP DNA on carcasses was probably derived from small numbers of MAP from the environment that contaminated the animals' hides. PMID:18450311

Meadus, W J; Gill, C O; Duff, P; Badoni, M; Saucier, L

2008-06-10

203

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins  

PubMed Central

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six ?-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come. PMID:24686769

Ben-Dov, Eitan

2014-01-01

204

Subandrodioecy and male fitness in Sagittaria lancifolia subsp. lancifolia (Alismataceae).  

PubMed

Sagittaria lancifolia subsp. lancifolia is described as cosexual (monoecious), but the study population consisted of 84% cosexuals that typically had 35% pistillate buds and 16% predominant males that typically had 0-2% pistillate buds. Hand-pollinations showed that pistillate flowers required pollination to set seed, and pollen from both male and cosexual plants was potent. No gender switching was seen in the field or greenhouse. From 24 experimental crosses, 890 offspring were grown to maturity. Among these, all offspring of cosexual sires were cosexual, but approximately half the offspring of male sires were male, implying that maleness was inherited as a single, dominant allele. These results indicate that S. lancifolia is subandrodioecious, a very rare breeding system. It is rare, in part because its maintenance requires a large male-fitness differential between male and cosexual plants. In the study population, this condition was met by the differential survival of staminate buds on male racemes. Larvae of the weevil Listronotus appendiculatus killed many staminate buds. They did so in a vertical gradient, with buds lower on racemes safer. Male plants have replaced pistillate with staminate buds at these safer positions and thereby enjoy disproportionally higher male fitness. PMID:21684934

Muenchow, G

1998-04-01

205

Bacillus thuringiensis subsp. israelensis and its dipteran-specific toxins.  

PubMed

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six ?-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come. PMID:24686769

Ben-Dov, Eitan

2014-04-01

206

Identification of immunoreactive proteins of Mycobacterium avium subsp. paratuberculosis.  

PubMed

Mycobacterium avium subsp. paratuberculosis (MAP) is the cause of a chronic enteritis of ruminants (bovine paratuberculosis (PTB)-Johne's disease) that is associated with enormous worldwide economic losses for the animal production. Diagnosis is based on observation of clinical signs, the detection of antibodies in milk or serum, or evaluation of bacterial culture from feces. The limit of these methods is that they are not able to detect the disease in the subclinical stage and are applicable only when the disease is already advanced. For this reason, the main purpose of this study is to use the MAP proteome to detect novel immunoreactive proteins that may be helpful for PTB diagnoses. 2DE and 2D immunoblotting of MAP proteins were performed using sera of control cattle and PTB-infected cattle in order to highlight the specific immunoreactive proteins. Among the assigned identifiers to immunoreactive spots it was found that most of them correspond to surface-located proteins while three of them have never been described before as antigens. The identification of these proteins improves scientific knowledge that could be useful for PTB diagnoses. The sequence of the identified protein can be used for the synthesis of immunoreactive peptides that could be screened for their immunoreaction against bovine sera infected with MAP. All MS data have been deposited in the ProteomeXchange consortium with identifier PXD001159 and DOI 10.6019/PXD001159. PMID:25404104

Piras, Cristian; Soggiu, Alessio; Bonizzi, Luigi; Greco, Viviana; Ricchi, Matteo; Arrigoni, Norma; Bassols, Anna; Urbani, Andrea; Roncada, Paola

2015-02-01

207

Anti-tumour activity of Digitalis purpurea L. subsp. heywoodii.  

PubMed

Recent research has shown the anticancer effects of digitalis compounds suggesting their possible use in medical oncology. Four extracts obtained from the leaves of Digitalis purpurea subsp. heywoodii have been assessed for cytotoxic activity against three human cancer cell lines, using the SRB assay. All of them showed high cytotoxicity, producing IC50 values in the 0.78 - 15 microg/mL range with the methanolic extract being the most active, in non toxic concentrations. Steroid glycosides (gitoxigenin derivatives) were detected in this methanolic extract. Gitoxigenin and gitoxin were evaluated in the SRB assay using the three human cancer cell lines, showing IC50 values in the 0.13 - 2.8 microM range, with the renal adenocarcinoma cancer cell line (TK-10) being the most sensitive one. Morphological apoptosis evaluation of the methanolic extract and both compounds on the TK-10 cell line showed that their cytotoxicity was mediated by an apoptotic effect. Finally, possible mechanisms involved in apoptosis induction by digitalis compounds are discussed. PMID:14531018

López-Lázaro, Miguel; Palma De La Peña, Nieves; Pastor, Nuria; Martín-Cordero, Carmen; Navarro, Eduardo; Cortés, Felipe; Ayuso, María Jesús; Toro, María Victoria

2003-08-01

208

Isolation of an endoglucanase gene from Bacteroides ruminicola subsp. brevis.  

PubMed

A gene coding for endo-1, 4-beta-glucanase activity has been isolated from Bacteroides ruminicola subsp. brevis by cloning in Escherichia coli. After restriction mapping of a 6.4 kb insert, a 2.2 kb DNA fragment was sub-cloned in pUC19 to produce the enzymically active clone pJW3. Recloning of the gene fragment in the reverse orientation in pUC18 (clone pJW4) indicated that a gene promoter was present in the cloned fragment and was able to function in E. coli. The clone pJW4 displayed increased activity which was attributed to expression from the lac promoter of pUC18. The enzyme encoded by pJW4 was optimally active at pH 5.5-6.0, and in the temperature range 37-42 degrees C. The preferred substrate was carboxymethylcellulose, but the enzyme displayed 50-60% of maximal activity on both acid-swollen cellulose and soluble xylan. No significant activity was detected on ball-milled filter paper or particulate xylan. Deletion experiments confirmed that both cellulase and xylanase activities were altered to a similar extent by deletion of DNA from the 3' end of the gene, suggesting that both are a function of the same polypeptide product. PMID:2628545

Woods, J R; Hudman, J F; Gregg, K

1989-09-01

209

Molecular organization of the 25S-18S rDNA IGS of Fagus sylvatica and Quercus suber: a comparative analysis.  

PubMed

The 35S ribosomal DNA (rDNA) units, repeated in tandem at one or more chromosomal loci, are separated by an intergenic spacer (IGS) containing functional elements involved in the regulation of transcription of downstream rRNA genes. In the present work, we have compared the IGS molecular organizations in two divergent species of Fagaceae, Fagus sylvatica and Quercus suber, aiming to comprehend the evolution of the IGS sequences within the family. Self- and cross-hybridization FISH was done on representative species of the Fagaceae. The IGS length variability and the methylation level of 18 and 25S rRNA genes were assessed in representatives of three genera of this family: Fagus, Quercus and Castanea. The intergenic spacers in Beech and Cork Oak showed similar overall organizations comprising putative functional elements needed for rRNA gene activity and containing a non-transcribed spacer (NTS), a promoter region, and a 5'-external transcribed spacer. In the NTS: the sub-repeats structure in Beech is more organized than in Cork Oak, sharing some short motifs which results in the lowest sequence similarity of the entire IGS; the AT-rich region differed in both spacers by a GC-rich block inserted in Cork Oak. The 5'-ETS is the region with the higher similarity, having nonetheless different lengths. FISH with the NTS-5'-ETS revealed fainter signals in cross-hybridization in agreement with the divergence between genera. The diversity of IGS lengths revealed variants from ? 2 kb in Fagus, and Quercus up to 5.3 kb in Castanea, and a lack of correlation between the number of variants and the number of rDNA loci in several species. Methylation of 25S Bam HI site was confirmed in all species and detected for the first time in the 18S of Q. suber and Q. faginea. These results provide important clues for the evolutionary trends of the rDNA 25S-18S IGS in the Fagaceae family. PMID:24893289

Inácio, Vera; Rocheta, Margarida; Morais-Cecílio, Leonor

2014-01-01

210

Molecular Organization of the 25S–18S rDNA IGS of Fagus sylvatica and Quercus suber: A Comparative Analysis  

PubMed Central

The 35S ribosomal DNA (rDNA) units, repeated in tandem at one or more chromosomal loci, are separated by an intergenic spacer (IGS) containing functional elements involved in the regulation of transcription of downstream rRNA genes. In the present work, we have compared the IGS molecular organizations in two divergent species of Fagaceae, Fagus sylvatica and Quercus suber, aiming to comprehend the evolution of the IGS sequences within the family. Self- and cross-hybridization FISH was done on representative species of the Fagaceae. The IGS length variability and the methylation level of 18 and 25S rRNA genes were assessed in representatives of three genera of this family: Fagus, Quercus and Castanea. The intergenic spacers in Beech and Cork Oak showed similar overall organizations comprising putative functional elements needed for rRNA gene activity and containing a non-transcribed spacer (NTS), a promoter region, and a 5?-external transcribed spacer. In the NTS: the sub-repeats structure in Beech is more organized than in Cork Oak, sharing some short motifs which results in the lowest sequence similarity of the entire IGS; the AT-rich region differed in both spacers by a GC-rich block inserted in Cork Oak. The 5?-ETS is the region with the higher similarity, having nonetheless different lengths. FISH with the NTS-5?-ETS revealed fainter signals in cross-hybridization in agreement with the divergence between genera. The diversity of IGS lengths revealed variants from ?2 kb in Fagus, and Quercus up to 5.3 kb in Castanea, and a lack of correlation between the number of variants and the number of rDNA loci in several species. Methylation of 25S Bam HI site was confirmed in all species and detected for the first time in the 18S of Q. suber and Q. faginea. These results provide important clues for the evolutionary trends of the rDNA 25S-18S IGS in the Fagaceae family. PMID:24893289

Inácio, Vera; Rocheta, Margarida; Morais-Cecílio, Leonor

2014-01-01

211

Bifidobacterium animalis subsp. lactis decreases urinary oxalate excretion in a mouse model of primary hyperoxaluria.  

PubMed

Hyperoxaluria significantly increases the risk of calcium oxalate kidney stone formation. Since several bacteria have been shown to metabolize oxalate in vitro, including probiotic bifidobacteria, we focused on the efficiency and possible mechanisms by which bifidobacteria can influence oxalate handling in vivo, especially in the intestines, and compared these results with the reported effects of Oxalobacter formigenes. Bifidobacterium animalis subsp. lactis DSM 10140 and B. adolescentis ATCC 15703 were administered to wild-type (WT) mice and to mice deficient in the hepatic enzyme alanine-glyoxylate aminotransferase (Agxt (-/-) , a mouse model of Primary Hyperoxaluria) that were fed an oxalate-supplemented diet. The administration of B. animalis subsp. lactis led to a significant decrease in urinary oxalate excretion in WT and Agxt (-/-) mice when compared to treatment with B. adolescentis. Detection of B. animalis subsp. lactis in feces revealed that 3 weeks after oral gavage with the bacteria 64 % of WT mice, but only 37 % of Agxt (-/-) mice were colonized. Examining intestinal oxalate fluxes showed there were no significant changes to net oxalate secretion in colonized animals and were therefore not associated with the changes in urinary oxalate excretion. These results indicate that colonization with B. animalis subsp. lactis decreased urinary oxalate excretion by degrading dietary oxalate thus limiting its absorption across the intestine but it did not promote enteric oxalate excretion as reported for O. formigenes. Preventive or therapeutic administration of B. animalis subsp. lactis appears to have some potential to beneficially influence dietary hyperoxaluria in mice. PMID:25269440

Klimesova, Klara; Whittamore, Jonathan M; Hatch, Marguerite

2015-04-01

212

Uptake and Persistence of Mycobacterium avium subsp. paratuberculosis in Human Monocytes  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is a bacterium sometimes found in human blood and tissue samples that may have a role in the etiology of Crohn's disease in humans. To date, however, there have been few studies examining the interactions of these bacteria with human cells. Using the THP-1 human monocytic cell line, this study shows that the uptake and trafficking of M. avium subsp. paratuberculosis in human cells are cholesterol dependent and that these bacteria localize to cholesterol-rich compartments that are slow to acidify. M. avium subsp. paratuberculosis bacteria containing phagosomes stain for the late endosomal marker Rab7, but recruitment of the Rab7-interacting lysosomal protein that regulates the fusion of bacterium-containing phagosomes with lysosomal compartments and facilitates subsequent bacterial clearance is significantly reduced. Disruption of phagosome acidification via this mechanism may contribute to M. avium subsp. paratuberculosis persistence in human cells, but there was no evidence that internalized M. avium subsp. paratuberculosis also affects the survival of bacteria taken up during a secondary phagocytic event. PMID:22890992

Keown, Dayle A.; Collings, David A.

2012-01-01

213

Fate of Mycobacterium avium subsp. paratuberculosis in Swiss Hard and Semihard Cheese Manufactured from Raw Milk  

PubMed Central

Raw milk was artificially contaminated with declumped cells of Mycobacterium avium subsp. paratuberculosis at a concentration of 104 to 105 CFU/ml and was used to manufacture model hard (Swiss Emmentaler) and semihard (Swiss Tisliter) cheese. Two different strains of M. avium subsp. paratuberculosis were tested, and for each strain, two model hard and semihard cheeses were produced. The survival of M. avium subsp. paratuberculosis cells was monitored over a ripening period of 120 days by plating out homogenized cheese samples onto 7H10-PANTA agar. In both the hard and the semihard cheeses, counts decreased steadily but slowly during cheese ripening. Nevertheless, viable cells could still be detected in 120-day cheese. D values were calculated at 27.8 days for hard and 45.5 days for semihard cheese. The most important factors responsible for the death of M. avium subsp. paratuberculosis in cheese were the temperatures applied during cheese manufacture and the low pH at the early stages of cheese ripening. Since the ripening period for these raw milk cheeses lasts at least 90 to 120 days, the D values found indicate that 103 to 104 cells of M. avium subsp. paratuberculosis per g will be inactivated. PMID:11526024

Spahr, U.; Schafroth, K.

2001-01-01

214

Novel Streptococcus infantarius subsp. infantarius variants harboring lactose metabolism genes homologous to Streptococcus thermophilus.  

PubMed

Streptococcus infantarius subsp. infantarius belongs to the Streptococcus bovis/Streptococcus equinus complex (SBSEC) commonly associated with human and animal infections. We elucidated the lactose metabolism of S. infantarius subsp. infantarius predominant in African fermented milk products. S. infantarius subsp. infantarius isolates (n = 192) were identified in 88% of spontaneously fermented camel milk suusac samples (n = 24) from Kenya and Somalia at log?? 8.2-8.5 CFU mL?¹. African S. infantarius isolates excreted stoichiometric amounts of galactose when grown on lactose, exhibiting a metabolism similar to Streptococcus thermophilus and distinct from their type strain. African S. infantarius subsp. infantarius CJ18 harbors a regular gal operon with 99.7-100% sequence identity to S. infantarius subsp. infantarius ATCC BAA-102(T) and a gal-lac operon with 91.7-97.6% sequence identity to S. thermophilus, absent in all sequenced SBSEC strains analyzed. The expression and functionality of lacZ was demonstrated in a ?-galactosidase assay. The gal-lac operon was identified in 100% of investigated S. infantarius isolates (n = 46) from suusac samples and confirmed in Malian fermented cow milk isolates. The African S. infantarius variant potentially evolved through horizontal gene transfer of an S. thermophilus-homologous lactose pathway. Safety assessments are needed to identify any putative health risks of this novel S. infantarius variant. PMID:22475940

Jans, Christoph; Gerber, Andrea; Bugnard, Joséphine; Njage, Patrick Murigu Kamau; Lacroix, Christophe; Meile, Leo

2012-08-01

215

Spatial analysis of Yersinia pestis and Bartonella vinsonii subsp. berkhoffii seroprevalence in California coyotes (Canis latrans).  

PubMed

Zoonotic transmission of sylvatic plague caused by Yersinia pestis occurs in California, USA. Human infections with various Bartonella species have been reported recently. Coyotes (Canis latrans) are ubiquitous throughout California and can become infected with both bacterial agents, making the species useful for surveillance purposes. This study examined the geographic distribution of 863 coyotes tested for Y. pestis and Bartonella vinsonii subsp. berkhoffii serologic status to gain insight into the natural history of B. vinsonii subsp. berkhoffii and to characterize the spatial distribution of the two agents. We found 11.7% of specimens positive to Y. pestis and 35.5% positive to B. vinsonii subsp. berkhoffii. The two pathogens had distinct spatial clusters: Y. pestis was more prevalent in eastern portions of the state and B. vinsonii subsp. berkhoffii in coastal regions. Prevalence of Y. pestis increased with increasing elevation, whereas prevalence of B. vinsonii subsp. berkhoffii decreased with increasing elevation. There were differences in the proportions of positive animals on a yearly basis to both pathogens. PMID:12507856

Hoar, B R; Chomel, B B; Rolfe, D L; Chang, C C; Fritz, C L; Sacks, B N; Carpenter, T E

2003-01-15

216

Xanthomonas citri subsp. citri type IV Pilus is required for twitching motility, biofilm development, and adherence.  

PubMed

Bacterial type IV pili (T4P) are long, flexible surface filaments that consist of helical polymers of mostly pilin subunits. Cycles of polymerization, attachment, and depolymerization mediate several pilus-dependent bacterial behaviors, including twitching motility, surface adhesion, pathogenicity, natural transformation, escape from immune system defense mechanisms, and biofilm formation. The Xanthomonas citri subsp. citri strain 306 genome codes for a large set of genes involved in T4P biogenesis and regulation and includes several pilin homologs. We show that X. citri subsp. citri can exhibit twitching motility in a manner similar to that observed in other bacteria such as Pseudomonas aeruginosa and Xylella fastidiosa and that this motility is abolished in Xanthomonas citri subsp. citri knockout strains in the genes coding for the major pilin subunit PilAXAC3241, the ATPases PilBXAC3239 and PilTXAC2924, and the T4P biogenesis regulators PilZXAC1133 and FimXXAC2398. Microscopy analyses were performed to compare patterns of bacterial migration in the wild-type and knockout strains and we observed that the formation of mushroom-like structures in X. citri subsp. citri biofilm requires a functional T4P. Finally, infection of X. citri subsp. citri cells by the bacteriophage (?Xacm4-11 is T4P dependent. The results of this study improve our understanding of how T4P influence Xanthomonas motility, biofilm formation, and susceptibility to phage infection. PMID:25180689

Dunger, German; Guzzo, Cristiane R; Andrade, Maxuel O; Jones, Jeffrey B; Farah, Chuck S

2014-10-01

217

Detection and Verification of Mycobacterium avium subsp. paratuberculosis in Fresh Ileocolonic Mucosal Biopsy Specimens from Individuals with and without Crohn's Disease  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis is a robust and phenotypically versatile pathogen which causes chronic inflammation of the intestine in many species, including primates. M. avium subsp. paratuberculosis infection is widespread in domestic livestock and is present in retail pasteurized cows' milk in the United Kingdom and, potentially, elsewhere. Water supplies are also at risk. The involvement of M. avium subsp.

Tim J. Bull; Elizabeth J. McMinn; Karim Sidi-Boumedine; Angela Skull; Damien Durkin; Penny Neild; Glenn Rhodes; Roger Pickup; John Hermon-Taylor

2003-01-01

218

THE ABILITY OF MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS TO ENTER BOVINE EPITHELIAL CELLS IS INFLUENCED BY PREEXPOSURE TO A HYPEROSMOLAR ENVIRONMENT AND INTRACELLULAR PASSAGE IN BOVINE MAMMARY EPITHELIAL CELLS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis is the cause of Johne’s disease in cattle and other ruminants. M. avium subsp. paratuberculosis infection of the bovine host is not well understood; however, it is assumed that crossing the bovine intestinal mucosa is important in order for M. avium subsp...

219

Virulence of Pasteurella multocida subsp. multocida isolated from outbreaks of fowl cholera in wild birds for domestic poultry and game birds  

Microsoft Academic Search

Chickens, turkeys, partridges and pheasants were experimentally infected with Pasteurella multocida subsp. multocida to investigate whether outbreaks of fowl cholera in avifauna might represent a risk for organic, backyard and industrial poultry production. Birds were infected intra-tracheally with a strain of P. multocida subsp. multocida (40605-1) isolated from outbreaks of fowl cholera in wild birds in Denmark. P. multocida subsp.

Kamille D. Petersen; Jens P. Christensen; Anders Permin; Magne Bisgaard

2001-01-01

220

Copper tolerance in the macrolichens Cladonia furcata and Cladina arbuscula subsp. mitis is constitutive rather than inducible  

Microsoft Academic Search

In this study we assessed the degree of copper (Cu) tolerance in two common lichen species (Cladonia furcata and Cladina arbuscula subsp. mitis) that grow on both uncontaminated substrata and the surface of waste heaps from abandoned old Cu-mines. Regardless of their locality, populations of these lichens contain identical strains of photobionts (Asterochloris clade A in C. arbuscula subsp. mitis

Martin Ba?kor; Evelin Ramóna Péli; Ivana Vantová

2011-01-01

221

Draft Genome Sequences of Campylobacter fetus subsp. venerealis bv. venerealis Strain B6 and bv. intermedius Strain 642-21.  

PubMed

Campylobacter fetus subsp. venerealis is an important venereal pathogen. We sequenced the genomes of Campylobacter fetus subsp. venerealis bv. venerealis strain B6 and bv. intermedius strain 642-21. The genetic variability of these Australian strains will facilitate the study of mechanisms of geographical adaptation of these pathogens that impact livestock. PMID:25278524

Barrero, Roberto A; Moolhuijzen, Paula; Indjein, Léa; Venus, Bronwyn; Keeble-Gagnère, Gabriel; Power, John; Bellgard, Matthew I; Lew-Tabor, Ala E

2014-01-01

222

The effectiveness of plant essential oils on the growth of Botrytis cinerea, Fusarium sp. and Clavibacter michiganensis subsp. michiganensis  

Microsoft Academic Search

Oregano, thyme, dictamnus, marjoram, lavender, rosemary, sage and pennyroyal essential oils were tested for their effectiveness against Botrytis cinerea, Fusarium sp. (Fusarium solani var. coeruleum), and Clavibacter michiganensis subsp. michiganensis on artificial growth media. The chemical composition of the oils was determined by gas chromatography-mass spectrometry (GC-MS). The growth of Botrytis cinerea, Fusarium sp. and Clavibacter michiganensis subsp. michiganensis was

Dimitra J Daferera; Basil N Ziogas; Moschos G Polissiou

2003-01-01

223

Rapid and Sensitive Method To Identify Mycobacterium avium subsp. paratuberculosis in Cow's Milk by DNA Methylase Genotyping  

PubMed Central

Paratuberculosis is an infectious, chronic, and incurable disease that affects ruminants, caused by Mycobacterium avium subsp. paratuberculosis. This bacterium is shed primarily through feces of infected cows but can be also excreted in colostrum and milk and might survive pasteurization. Since an association of genomic sequences of M. avium subsp. paratuberculosis in patients with Crohn's disease has been described; it is of interest to rapidly detect M. avium subsp. paratuberculosis in milk for human consumption. IS900 insertion is used as a target for PCR amplification to identify the presence of M. avium subsp. paratuberculosis in biological samples. Two target sequences were selected: IS1 (155 bp) and IS2 (94 bp). These fragments have a 100% identity among all M. avium subsp. paratuberculosis strains sequenced. M. avium subsp. paratuberculosis was specifically concentrated from milk samples by immunomagnetic separation prior to performing PCR. The amplicons were characterized using DNA methylase Genotyping, i.e., the amplicons were methylated with 6-methyl-adenine and digested with restriction enzymes to confirm their identity. The methylated amplicons from 100 CFU of M. avium subsp. paratuberculosis can be visualized in a Western blot format using an anti-6-methyl-adenine monoclonal antibody. The use of DNA methyltransferase genotyping coupled to a scintillation proximity assay allows for the detection of up to 10 CFU of M. avium subsp. paratuberculosis per ml of milk. This test is rapid and sensitive and allows for automation and thus multiple samples can be tested at the same time. PMID:23275511

Mundo, Silvia Leonor; Gilardoni, Liliana Rosa; Hoffman, Federico José

2013-01-01

224

Culture and Serologic Survey for Mycobacterium avium subsp. paratuberculosis Infection among Southeastern White-tailed Deer (Odocoileus virginianus)  

Microsoft Academic Search

From July 1998 through October 2002, radiometric culture (ileocecal lymph node, mesenteric lymph node, and feces) and serologic testing by enzyme-linked immunosor- bent assay (ELISA) were used to survey white- tailed deer (Odocoileus virginianus) from the southeastern United States for infection by My- cobacterium avium subsp. paratuberculosis (Mptb), the causative agent of paratuberculosis (Johne's disease). Mycobacterium avium subsp. paratuberculosis was

William R. Davidson; Elizabeth J. B. Manning; Victor F. Nettles; D. B. Warnell

225

The genome of Aeromonas salmonicida subsp. salmonicida A449: insights into the evolution of a fish pathogen  

Microsoft Academic Search

BACKGROUND: Aeromonas salmonicida subsp. salmonicida is a Gram-negative bacterium that is the causative agent of furunculosis, a bacterial septicaemia of salmonid fish. While other species of Aeromonas are opportunistic pathogens or are found in commensal or symbiotic relationships with animal hosts, A. salmonicida subsp. salmonicida causes disease in healthy fish. The genome sequence of A. salmonicida was determined to provide

Michael E Reith; Rama K Singh; Bruce Curtis; Jessica M Boyd; Anne Bouevitch; Jennifer Kimball; Janet Munholland; Colleen Murphy; Darren Sarty; Jason Williams; John HE Nash; Stewart C Johnson; Laura L Brown

2008-01-01

226

Distribution of Bacillus thuringiensis subsp. israelensis in Soil of a Swiss Wetland Reserve after 22 Years of Mosquito Control?†  

PubMed Central

Recurrent treatments with Bacillus thuringiensis subsp. israelensis are required to control the floodwater mosquito Aedes vexans that breeds in large numbers in the wetlands of the Bolle di Magadino Reserve in Canton Ticino, Switzerland. Interventions have been carried out since 1988. In the present study, the spatial distribution of resting B. thuringiensis subsp. israelensis spores in the soil was measured. The B. thuringiensis subsp. israelensis concentration was determined in soil samples collected along six transects covering different elevations within the periodically flooded zones. A total of 258 samples were processed and analyzed by quantitative PCR that targeted an identical fragment of 159 bp for the B. thuringiensis subsp. israelensis cry4Aa and cry4Ba genes. B. thuringiensis subsp. israelensis spores were found to persist in soils of the wetland reserve at concentrations of up to 6.8 log per gram of soil. Continuous accumulation due to regular treatments could be excluded, as the decrease in spores amounted to 95.8% (95% confidence interval, 93.9 to 97.7%). The distribution of spores was correlated to the number of B. thuringiensis subsp. israelensis treatments, the elevation of the sampling point, and the duration of the flooding periods. The number of B. thuringiensis subsp. israelensis treatments was the major factor influencing the distribution of spores in the different topographic zones (P < 0.0001). These findings indicated that B. thuringiensis subsp. israelensis spores are rather immobile after their introduction into the environment. PMID:21498758

Guidi, Valeria; Patocchi, Nicola; Lüthy, Peter; Tonolla, Mauro

2011-01-01

227

Complete Genome Sequence of Campylobacter fetus subsp. testudinum Strain Pet-3, Isolated from a Lizard (Hydrosaurus pustulatus)  

PubMed Central

The whole-genome sequence for Campylobacter fetus subsp. testudinum, a pathogen isolated from humans and turtles, has been reported recently. We present another completed genome sequence of the C. fetus subsp. testudinum strain pet-3, which was isolated from a lizard in Taiwan, for further genomic comparison study. PMID:25700400

Wu, Zong-Yen; Shia, Wei-Yau; Jhou, Yi-Jyun; Tung, Kwong-Chung; Shyu, Ching-Lin

2015-01-01

228

Complete Genome Sequence of Campylobacter fetus subsp. testudinum Strain Pet-3, Isolated from a Lizard (Hydrosaurus pustulatus).  

PubMed

The whole-genome sequence for Campylobacter fetus subsp. testudinum, a pathogen isolated from humans and turtles, has been reported recently. We present another completed genome sequence of the C. fetus subsp. testudinum strain pet-3, which was isolated from a lizard in Taiwan, for further genomic comparison study. PMID:25700400

Wang, Chao-Min; Wu, Zong-Yen; Shia, Wei-Yau; Jhou, Yi-Jyun; Tung, Kwong-Chung; Shyu, Ching-Lin

2015-01-01

229

Protection from UV-B Damage of Mosquito Larvicidal Toxins from Bacillus thuringiensis subsp. israelensis Expressed in  

E-print Network

pigments act as UV-B photopro- tectors [11, 13]; these microorganisms are, therefore, likely to preserveProtection from UV-B Damage of Mosquito Larvicidal Toxins from Bacillus thuringiensis subsp proteins of Bacillus thuringiensis subsp. israelensis from damage inflicted by UV-B, a sunlight component

Zaritsky, Arieh

230

Dissemination of the superantigen encoding genes seeL, seeM, szeL and szeM in Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus.  

PubMed

Bacterial superantigens are one of the major virulence factors produced by Streptococcus pyogenes and Staphylococcus aureus. The two novel superantigen encoding genes seeM and seeL were described for S. equi subsp. equi which is known as the causative agent of strangles in equids. In the present study previously characterized S. equi subsp. equi strains and strains of various other animal pathogenic streptococcal species and subspecies were investigated for the presence of the superantigen encoding genes seeM and seeL by polymerase chain reaction. According to these studies seeL and seeM appeared to be a constant characteristic of all investigated S. equi subsp. equi strains. Surprisingly, one S. equi subsp. zooepidemicus strain (S.z. 122) was also positive for both genes. The species identity of this S. equi subsp. zooepidemicus strain could additionally be confirmed by sequencing the 16S rRNA gene and the 16S-23S rDNA intergenic spacer region. The superantigen encoding genes could not be found among additionally investigated S. equi subsp. zooepidemicus strains or among strains of seven other streptococcal species. The seeL and seeM genes of the S. equi subsp. equi strain S.e. CF32 and the genes szeL and szeM of the S. equi subsp. zooepidemicus strain S.z. 122 were cloned and sequenced. A sequence comparison revealed a high degree of sequence homology between seeL, szeL, speL and seeM, szeM and speM, respectively. The superantigenic toxins L and M seemed to be widely distributed virulence factors of S. equi subsp. equi, rare among S. equi subsp. zooepidemicus but did not occur among a number of other animal pathogenic streptococcal species. PMID:15953700

Alber, J; El-Sayed, A; Estoepangestie, S; Lämmler, C; Zschöck, M

2005-08-10

231

Leaf morphology and phenology of Beech (Fagus sylvatica L.) are linked to environmental conditions depending on the altitudinal origin  

NASA Astrophysics Data System (ADS)

One of the principal responses of temperate climate trees to climate warming, besides migration, will be in-situ adaptation/evolution. For both, germination and growth rates can have a strong impact on survival and long-term recruitment and establishment of a species. Leaf morphology traits, together with phenology, are relevant to the study of inherent capacities of plants to adapt to an ever changing climate, especially in alpine regions, where a rapid warming has been observed in the last decades. The aim of this study was to evaluate the changes in possible adaptive traits (e.g. leaf morphology and phenology) of Beech (Fagus sylvatica L.) and to asses a decisive component of the survival strategy of this important broadly distributed Central European tree species. We collected beech seeds at six sites along two transects of a south- (900, 1000 and 1100-1400 m.a.s.l.) and a north-facing slope (800, 900 and 1100 m.a.s.l.) in 2011 (mast year) near Garmisch-Partenkirchen, Germany. All the seeds were stratified before sowing; 150 seeds were selected from each site and sowed (at the beginning of the spring) in square containers in a greenhouse under the same climatic conditions; seven phenological stages were defined following a modified beech germination key and the phenology of every seed was recorded three times a week. Harvesting took place 38/42 days after sowing and the specific leaf area (SLA), biomass, and leaf morphology (lamina length and width) were recorded for each seedling. Seeds from lower sites of the two transects presented a poorer germination rates (e.g. 30% for the south 900 m.a.s.l. site) and (75% for the north 800 m.a.s.l. site) when compared to seeds originating from higher elevations within the same transect. The highest germination percentages (98 and 85%) were observed in seeds originating from the highest elevations (e.g. 1100-1400 m.a.s.l. of the south site and 1100 m.a.s.l. of the north site, respectively). Although no significant differences in SLA were found among the altitudinal levels in any of the transects, significant differences were found in biomass among the two highest sites of the two transects. The length of the lamina differed significantly between 900 to 1100-1400 m.a.s.l. in the south facing transect, while in the north facing transect the lamina width showed significant differences between the highest and the lower sites. A higher percentage of germination of seeds originating from higher altitudinal sites may points to a developed sensitivity to environmental changes and a rapid and more favorable response. Our results suggest, contrary to what has been reported, (leaf size differentiation among altitudinal sites under natural conditions), that the altitude of origin doesn't have an overriding impact on leaf morphological responses when growing under the same conditions, indicating that leaf morphology and phenology may have an adaptive significance linked to climate.

Capdevielle-Vargas, Renee; Schuster, Christina; Estrella, Nicole; Menzel, Annette

2014-05-01

232

The influence of stemflow from an European Beech Tree (Fagus Sylvatica L.) on soil solution and seepage fluxes  

NASA Astrophysics Data System (ADS)

European Beech (Fagus sylcatica L.) is particularly prone to produce large amounts of stemflow even during comparatively small precipitation events. This may lead to preferential flow and solute transport to greater depths next to the stem at lower precipitation heights than would be expected without considering water redistribution by the canopy. In this study we investigated the influence of beech stemflow on soil solution and seepage fluxes, based on observed quality of all precipitation components as well as soil water. For estimation of transport, the soil water flow was modeled. We measured concentrations of Na+, K+, Mg2+, Ca2+, NH4+-N, NO3--N, Dissolved Organic Nitrogen (DON) and Dissolved Organic Carbon (DOC) in throughfall, stemflow and soil solution at depths of 10 cm and 30 cm and stem distances of 10 cm, 40 cm and 100 cm during autumn 2012 and spring and summer 2013. Throughfall and stemflow were sampled at 38 precipitation events during summer and autumn 2012 and summer 2013 from 192 (throughfall) and 16 (stemflow) collectors, respectively. Soil solutions were collected on 10 events during autumn 2012 and spring and summer 2013. Element fluxes were calculated from the chemical and hydrological measurements and model results. Water flow through the soil was calculated using the model VS2DTI and was based on Richard's equation and the model of van Genuchten and Mualem for predicting unsaturated hydraulic conductivity. The model also accounted for evapotranspiration, which was estimated using the Penman-Monteith equation with meteorological data from a nearby weather station. Longterm time series of throughfall and stemflow were estimated based on the observed relations and using rainfall data from the same weather station. Since the actual stemflow infiltration area was unknown, two scenarios with assumed infiltration areas of 1 m² and 2.76 m² were calculated. All concentrations and fluxes were within the range of published results. However, stemflow fluxes could not be estimated reliably due to missing information on the actual infiltration area. Our data suggest that the influence of stemflow on soil solution seems to reach to at least up to 40 cm stem distance but not as far as 100 cm distance from the stem. We observed lower element concentrations in soil solution next to the stem, which may be a result of the locally increased water input, therefore diluting element concentrations. Element seepage fluxes calculated from modeled water fluxes were lower than measured fluxes, due to an overestimation of transpiration by the model. With the given setup the model did not indicate a significant importance of stemflow on water or element seepage fluxes. Further development should include enhancing the model to account for preferential flow patterns, recalculating of evapotranspiration and consideration of its spatial distribution and integrating in situ measured soil properties.

Dalla Valle, Nicolas; Michalzik, Beate; Hildebrandt, Anke

2014-05-01

233

The expression of an abscisic acid-responsive glycine-rich protein coincides with the level of seed dormancy in Fagus sylvatica.  

PubMed

By differential screening of a cDNA library constructed from poly (A+) RNA of ABA-treated seeds of Fagus sylvatica L., we have isolated an ABA-responsive clone that is present in dormant seeds and under conditions that maintain dormancy, but it tends to disappear under conditions breaking seed dormancy. A search of the sequence data bases showed that the clone codes for a Glycine-Rich Protein and has sequence similarity to RNA-binding proteins. The clone, which exibits the characteristics of lea-genes, is up-regulated by ABA and down-regulated by GA3. Paclobutrazol abolishes the effect of GA3, which is restored upon addition of GA3. The possible relationship of this Glycine-Rich Protein to seed dormancy in F. sylvatica is discussed. PMID:9522463

Nicolás, C; Rodríguez, D; Poulsen, F; Eriksen, E N; Nicolás, G

1997-12-01

234

Growth losses in Swiss forests caused by ozone: epidemiological data analysis of stem increment of Fagus sylvatica L. and Picea abies Karst.  

PubMed

The estimate of growth losses by ozone exposure of forest trees is a significant part in current C sequestration calculations and will also be important in future modeling. It is therefore important to know if the relationship between ozone flux and growth reduction of young trees, used to derive a Critical Level for ozone, is also valid for mature trees. Epidemiological analysis of stem increment data from Fagus sylvatica L. and Picea abies Karst. observed in Swiss forest plots was used to test this hypothesis. The results confirm the validity of the flux-response relationship at least for beech and therefore enable estimating forest growth losses by ozone on a country-wide scale. For Switzerland, these estimates amount to 19.5% growth reduction for deciduous forests, 6.6% for coniferous forests and 11.0% for all forested areas based on annual ozone stomatal uptake during the time period 1991-2011. PMID:24911370

Braun, Sabine; Schindler, Christian; Rihm, Beat

2014-09-01

235

Modeling of stomatal conductance to estimate stomatal ozone uptake by Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla.  

PubMed

To construct stomatal conductance models and estimate stomatal O3 uptake for Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla, stomatal conductance (gs) was measured in seedlings of the four tree species. Better estimates of gs were made by incorporating the acute effects of O3 on gs into the models and the models could explain 34-52% of the variability in gs. Although the O3 concentration was relatively high in spring from April to May, COU of F. crenata, Q. serrata and Q. mongolica var. crispula were relatively low and the ratios of COU in spring to total COU in one year were 16.8% in all tree species because of low gs limited mainly by leaf pre-maturation and/or low temperature. The COU of B. platyphylla were relatively high mainly because of rapid leaf maturation and lower optimal temperature for stomatal opening. PMID:25150506

Kinose, Yoshiyuki; Azuchi, Fumika; Uehara, Yui; Kanomata, Tomoaki; Kobayashi, Ayumi; Yamaguchi, Masahiro; Izuta, Takeshi

2014-11-01

236

Persistence and recycling of bioinsecticidal Bacillus thuringiensis subsp. israelensis spores in contrasting environments: evidence from field monitoring and laboratory experiments.  

PubMed

Sprays of commercial preparations of the bacterium Bacillus thuringiensis subsp. israelensis are widely used for the control of mosquito larvae. Despite an abundant literature on B. thuringiensis subsp. israelensis field efficiency on mosquito control, few studies have evaluated the fate of spores in the environment after treatments. In the present article, two complementary experiments were conducted to study the effect of different parameters on B. thuringiensis subsp. israelensis persistence and recycling, in field conditions and in the laboratory. First, we monitored B. thuringiensis subsp. israelensis persistence in the field in two contrasting regions in France: the Rhône-Alpes region, where mosquito breeding sites are temporary ponds under forest cover with large amounts of decaying leaf matter on the ground and the Mediterranean region characterized by open breeding sites such as brackish marshes. Viable B. thuringiensis subsp. israelensis spores can persist for months after a treatment, and their quantity is explained both by the vegetation type and by the number of local treatments. We found no evidence of B. thuringiensis subsp. israelensis recycling in the field. Then, we tested the effect of water level, substrate type, salinity and presence of mosquito larvae on the persistence/recycling of B. thuringiensis subsp. israelensis spores in controlled laboratory conditions (microcosms). We found no effect of change in water level or salinity on B. thuringiensis subsp. israelensis persistence over time (75 days). B. thuringiensis subsp. israelensis spores tended to persist longer in substrates containing organic matter compared to sand-only substrates. B. thuringiensis subsp. israelensis recycling only occurred in presence of mosquito larvae but was unrelated to the presence of organic matter. PMID:24402370

Duchet, Claire; Tetreau, Guillaume; Marie, Albane; Rey, Delphine; Besnard, Gilles; Perrin, Yvon; Paris, Margot; David, Jean-Philippe; Lagneau, Christophe; Després, Laurence

2014-04-01

237

Invasion and persistence of Mycobacterium avium subsp. paratuberculosis during early stages of Johne's disease in calves.  

PubMed

Infection with Mycobacterium avium subsp. paratuberculosis causes Johne's disease in cattle and is a serious problem for the dairy industry worldwide. Development of models to mimic aspects of Johne's disease remains an elusive goal because of the chronic nature of the disease. In this report, we describe a surgical approach employed to characterize the very early stages of infection of calves with M. avium subsp. paratuberculosis. To our surprise, strains of M. avium subsp. paratuberculosis were able to traverse the intestinal tissues within 1 h of infection in order to colonize distant organs, such as the liver and lymph nodes. Both the ileum and the mesenteric lymph nodes were persistently infected for months following intestinal deposition of M. avium subsp. paratuberculosis despite a lack of fecal shedding of mycobacteria. During the first 9 months of infection, humoral immune responses were not detected. Nonetheless, using flow cytometric analysis, we detected a significant change in the cells participating in the inflammatory responses of infected calves compared to cells in a control animal. Additionally, the levels of cytokines detected in both the ileum and the lymph nodes indicated that there were TH1-type-associated cellular responses but not TH2-type-associated humoral responses. Finally, surgical inoculation of a wild-type strain and a mutant M. avium subsp. paratuberculosis strain (with an inactivated gcpE gene) demonstrated the ability of the model which we developed to differentiate between the wild-type strain and a mutant strain of M. avium subsp. paratuberculosis deficient in tissue colonization and invasion. Overall, novel insights into the early stages of Johne's disease were obtained, and a practical model of mycobacterial invasiveness was developed. A similar approach can be used for other enteric bacteria. PMID:17296749

Wu, Chia-wei; Livesey, Michael; Schmoller, Shelly K; Manning, Elizabeth J B; Steinberg, Howard; Davis, William C; Hamilton, Mary Jo; Talaat, Adel M

2007-05-01

238

Aeromonas hydrophila subsp. dhakensis Isolated from Feces, Water and Fish in Mediterranean Spain  

PubMed Central

Eight Aeromonas hydrophila-like arabinose-negative isolates from diverse sources (i.e., river freshwater, cooling-system water pond, diseased wild European eels, and human stools) sampled in Valencia (Spain) during 2004–2005, were characterized by 16S rRNA gene sequencing and extensive biochemical testing along with reference strains of most Aeromonas species. These isolates and all reference strains of A. hydrophila subsp. dhakensis and A. aquariorum showed a 16S rRNA sequence similarity of 99.8–100%, and they all shared an identical phenotype. This matched exactly with that of A. hydrophila subsp. dhakensis since all strains displayed positive responses to the Voges-Prokauer test and to the use of dl-lactate. This is the first report of A. hydrophila subsp. dhakensis recovered from environmental samples, and further, from its original isolation in India during 1993–1994. This was accurately identified and segregated from other clinical aeromonads (A. hydrophila subsp. hydrophila, A. caviae, A. veronii biovars veronii and sobria, A. trota, A. schubertii and A. jandaei) by using biochemical key tests. The API 20 E profile for all strains included in A. hydrophila subsp. dhakensis was 7047125. The prevalence of this species in Spanish sources was higher for water (9.4%) than for feces (6%) or eels (1.3%). Isolates recovered as pure cultures from diseased eels were moderately virulent (LD50 of 3.3×106 CFU fish?1) to challenged eels in experimental trials. They were all resistant to ticarcillin, amoxicillin-clavuranic acid, cefoxitin, and imipenem, regardless of its source. Our data point to A. hydrophila subsp. dhakensis as an emerging pathogen for humans and fish in temperate countries. PMID:22472298

Esteve, Consuelo; Alcaide, Elena; Blasco, María Dolores

2012-01-01

239

Culture Phenotypes of Genomically and Geographically Diverse Mycobacterium avium subsp. paratuberculosis Isolates from Different Hosts?  

PubMed Central

Mycobacterium avium subsp. paratuberculosis causes paratuberculosis (Johne's disease) in ruminants in most countries. Historical data suggest substantial differences in culturability of M. avium subsp. paratuberculosis isolates from small ruminants and cattle; however, a systematic comparison of culture media and isolates from different countries and hosts has not been undertaken. Here, 35 field isolates from the United States, Spain, Northern Ireland, and Australia were propagated in Bactec 12B medium and Middlebrook 7H10 agar, genomically characterized, and subcultured to Lowenstein-Jensen (LJ), Herrold's egg yolk (HEY), modified Middlebrook 7H10, Middlebrook 7H11, and Watson-Reid (WR) agars, all with and without mycobactin J and some with sodium pyruvate. Fourteen genotypes of M. avium subsp. paratuberculosis were represented as determined by BstEII IS900 and IS1311 restriction fragment length polymorphism analysis. There was no correlation between genotype and overall culturability, although most S strains tended to grow poorly on HEY agar. Pyruvate was inhibitory to some isolates. All strains grew on modified Middlebrook 7H10 agar but more slowly and less prolifically on LJ agar. Mycobactin J was required for growth on all media except 7H11 agar, but growth was improved by the addition of mycobactin J to 7H11 agar. WR agar supported the growth of few isolates. The differences in growth of M. avium subsp. paratuberculosis that have historically been reported in diverse settings have been strongly influenced by the type of culture medium used. When an optimal culture medium, such as modified Middlebrook 7H10 agar, is used, very little difference between the growth phenotypes of diverse strains of M. avium subsp. paratuberculosis was observed. This optimal medium is recommended to remove bias in the isolation and cultivation of M. avium subsp. paratuberculosis. PMID:21430104

Whittington, Richard J.; Marsh, Ian B.; Saunders, Vanessa; Grant, Irene R.; Juste, Ramon; Sevilla, Iker A.; Manning, Elizabeth J. B.; Whitlock, Robert H.

2011-01-01

240

Genome-Wide DNA Microarray Analysis of Francisella tularensis Strains Demonstrates Extensive Genetic Conservation within the Species but Identifies Regions That Are Unique to the Highly Virulent F. tularensis subsp. tularensis  

Microsoft Academic Search

Francisella tularensis is a potent pathogen and a possible bioterrorism agent. Little is known, however, to ex- plain the molecular basis for its virulence and the distinct differences in virulence found between the four rec- ognized subspecies, F. tularensis subsp. tularensis, F. tularensis subsp. mediasiatica, F. tularensis subsp. holarc- tica, and F. tularensis subsp. novicida. We developed a DNA microarray

Martien Broekhuijsen; Par Larsson; Anders Johansson; Mona Bystrom; Ulla Eriksson; Eva Larsson; Richard G. Prior; Anders Sjostedt; Richard W. Titball; Mats Forsman; TNO Prins

2003-01-01

241

Seroepidemiology of Bartonella vinsonii subsp. berkhoffii infection in California coyotes, 1994-1998.  

PubMed

The prevalence of antibodies to Bartonella vinsonii subsp. berkhoffii in coyotes (Canis latrans) in California ranged from 51% in central to 34% in southern and 7% in northern California. Seropositive coyotes were more likely to be from coastal than inland counties (p clustered distribution of Bartonella seropositivity in coyotes suggests that B. vinsonii subsp. berkhoffii infection is vectorborne. Further investigation is warranted to evaluate which arthropods are vectors and what the mode of transmission is from wildlife to domestic dogs and possibly humans. PMID:10511529

Chang, C; Yamamoto, K; Chomel, B B; Kasten, R W; Simpson, D C; Smith, C R; Kramer, V L

1999-01-01

242

Finished Genome of Zymomonas mobilis subsp. mobilis Strain CP4, an Applied Ethanol Producer.  

PubMed

Zymomonas mobilis subsp. mobilis is one of the most rigorous ethanol-producing organisms known to date, considered by many to be the prokaryotic alternative to yeast. The two most applied Z. mobilis subsp. mobilis strains, ZM4 and CP4, derive from Recife, Brazil, and have been isolated from sugarcane fermentations. Of these, ZM4 was the first Z. mobilis representative strain to be sequenced and analyzed. Here, we report the finishing of the genome sequence of strain CP4, which is highly similar but not identical to that of ZM4. PMID:24407627

Kouvelis, Vassili N; Teshima, Hazuki; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Tampakopoulou, Vassileia-Olga; Goodwin, Lynne; Woyke, Tanja; Kyrpides, Nikos C; Typas, Milton A; Pappas, Katherine M

2014-01-01

243

Fingerprinting of Salmonella enterica subsp. enterica serovar Enteritidis by ribotyping.  

PubMed

OBJECTIVE: To carry out an epidemiologic evaluation of Salmonella enterica subsp. enterica serovar Enteritidis outbreaks in households and small communities by means of rRNA gene restriction pattern analysis (ribotyping). METHODS: One hundred Enteritidis isolates dating from 1989 to 1994 which could be allocated epidemiologically to different sources or to small community outbreaks were investigated with ribotyping, a fingerprinting method in which bacterial DNA is hybridized with the biotin-labeled plasmid pKK 3535 containing a ribosomal RNA operon of Escherichia coli to determine the ribosomal RNA gene restriction patterns. RESULTS: Four different ribotyping patterns were found with the restriction endonuclease Smal and nine with Sphl. Ribotypes of isolates which could be allocated epidemiologically to a common source usually corresponded. Almost 60% of the Enteritidis infections had the ribotyping pattern Sphl-A. In contrast, this pattern was not found in any of the five Enteritidis strains isolated in 1989. The suspicion that Enteritidis phage type 4 infections are caused by consumption of insufficiently heated eggs is supported by the fact that the ribotyping pattern Sph1-A was found in isolates from eggs and from human specimens. CONCLUSIONS: As patterns Sphl-A and Smal-J appeared in 58% and 75% of the isolates, respectively, ribotyping cannot be used for the differentiation between various outbreaks with these two patterns. In cases where the Enteritidis strains showed less frequent patterns, ribotyping seems to be a practical tool for the identification of infection chains. In addition newly appearing ribotyping patterns can give information about the epidemiologic development of Enteritidis infection. PMID:11864109

Lippelt, Meike; de Isele, Theresa Sanabria; Kist, Manfred

1997-04-01

244

Virulence differences among Francisella tularensis subsp. tularensis clades in mice.  

PubMed

Francisella tularensis subspecies tularensis (type A) and holarctica (type B) are of clinical importance in causing tularemia. Molecular typing methods have further separated type A strains into three genetically distinct clades, A1a, A1b and A2. Epidemiological analyses of human infections in the United States suggest that A1b infections are associated with a significantly higher mortality rate as compared to infections caused by A1a, A2 and type B. To determine if genetic differences as defined by molecular typing directly correlate with differences in virulence, A1a, A1b, A2 and type B strains were compared in C57BL/6 mice. Here we demonstrate significant differences between survival curves for infections caused by A1b versus A1a, A2 and type B, with A1b infected mice dying earlier than mice infected with A1a, A2 or type B; these results were conserved among multiple strains. Differences were also detected among type A clades as well as between type A clades and type B with respect to bacterial burdens, and gross anatomy in infected mice. Our results indicate that clades defined within F. tularensis subsp. tularensis by molecular typing methods correlate with virulence differences, with A1b strains more virulent than A1a, A2 and type B strains. These findings indicate type A strains are not equivalent with respect to virulence and have important implications for public health as well as basic research programs. PMID:20419133

Molins, Claudia R; Delorey, Mark J; Yockey, Brook M; Young, John W; Sheldon, Sarah W; Reese, Sara M; Schriefer, Martin E; Petersen, Jeannine M

2010-01-01

245

Virulence Differences Among Francisella tularensis Subsp. tularensis Clades in Mice  

PubMed Central

Francisella tularensis subspecies tularensis (type A) and holarctica (type B) are of clinical importance in causing tularemia. Molecular typing methods have further separated type A strains into three genetically distinct clades, A1a, A1b and A2. Epidemiological analyses of human infections in the United States suggest that A1b infections are associated with a significantly higher mortality rate as compared to infections caused by A1a, A2 and type B. To determine if genetic differences as defined by molecular typing directly correlate with differences in virulence, A1a, A1b, A2 and type B strains were compared in C57BL/6 mice. Here we demonstrate significant differences between survival curves for infections caused by A1b versus A1a, A2 and type B, with A1b infected mice dying earlier than mice infected with A1a, A2 or type B; these results were conserved among multiple strains. Differences were also detected among type A clades as well as between type A clades and type B with respect to bacterial burdens, and gross anatomy in infected mice. Our results indicate that clades defined within F. tularensis subsp. tularensis by molecular typing methods correlate with virulence differences, with A1b strains more virulent than A1a, A2 and type B strains. These findings indicate type A strains are not equivalent with respect to virulence and have important implications for public health as well as basic research programs. PMID:20419133

Molins, Claudia R.; Delorey, Mark J.; Yockey, Brook M.; Young, John W.; Sheldon, Sarah W.; Reese, Sara M.; Schriefer, Martin E.; Petersen, Jeannine M.

2010-01-01

246

Heat inactivation of Mycobacterium avium subsp. paratuberculosis in milk.  

PubMed

The effectiveness of pasteurization and the concentration of Mycobacterium avium subsp. paratuberculosis in raw milk have been identified in quantitative risk analysis as the most critical factors influencing the potential presence of viable Mycobacterium paratuberculosis in dairy products. A quantitative assessment of the lethality of pasteurization was undertaken using an industrial pasteurizer designed for research purposes with a validated Reynolds number of 62,112 and flow rates of 3,000 liters/h. M. paratuberculosis was artificially added to raw whole milk, which was then homogenized, pasteurized, and cultured, using a sensitive technique capable of detecting one organism per 10 ml of milk. Twenty batches of milk containing 10(3) to 10(4) organisms/ml were processed with combinations of three temperatures of 72, 75, and 78 degrees C and three time intervals of 15, 20, and 25 s. Thirty 50-ml milk samples from each processed batch were cultured, and the logarithmic reduction in M. paratuberculosis organisms was determined. In 17 of the 20 runs, no viable M. paratuberculosis organisms were detected, which represented > 6-log10 reductions during pasteurization. These experiments were conducted with very heavily artificially contaminated milk to facilitate the measurement of the logarithmic reduction. In three of the 20 runs of milk, pasteurized at 72 degrees C for 15 s, 75 degrees C for 25 s, and 78 degrees C for 15 s, a few viable organisms (0.002 to 0.004 CFU/ml) were detected. Pasteurization at all temperatures and holding times was found to be very effective in killing M. paratuberculosis, resulting in a reduction of > 6 log10 in 85% of runs and > 4 log10 in 14% of runs. PMID:15812001

McDonald, Wendy L; O'Riley, Kimberly J; Schroen, Christopher J; Condron, Robin J

2005-04-01

247

Reproductive biology of the andromonoecious Cucumis melo subsp. agrestis (Cucurbitaceae)  

PubMed Central

Background and Aims Cucumis melo subsp. agrestis (Cucurbitaceae) is cultivated in many African regions for its edible kernels used as a soup thickener. The plant, an annual, andromonoecious, trailing-vine species, is of high social, cultural and economic value for local communities. In order to improve the yield of this crop, the first step and our aim were to elucidate its breeding system. Methods Eight experimental pollination treatments were performed during three growing seasons to assess spontaneous selfing, self-compatibility and effects of pollen source (hermaphroditic vs. male flowers). Pollination success was determined by pollen tube growth and reproductive success was assessed by fruit, seed and seedling numbers and characteristics. The pollinator guild was surveyed and the pollination distance determined both by direct observations and by indirect fluorescent dye dispersal. Key Results The species is probably pollinated by several Hymenoptera, principally by Hypotrigona para. Pollinator flight distances varied from 25 to 69 cm. No evidence for apomixis or spontaneous self-pollination in the absence of insect visitors was found. The self-fertility index (SFI = 0) indicated a total dependence on pollinators for reproductive success. The effects of hand pollination on fruit set, seed number and seedling fitness differed among years. Pollen tube growth and reproductive success did not differ between self- and cross-pollinations. Accordingly, a high self-compatibility index for the fruit set (SCI = 1·00) and the seed number (SCI = 0·98) and a low inbreeding depression at all developmental stages (cumulative ? = 0·126) suggest a high selfing ability. Finally, pollen origin had no effect on fruit and seed sets. Conclusions This andromonoecious species has the potential for a mixed mating system with high dependence on insect-mediated pollination. The selfing rate through geitonogamy should be important. PMID:19671577

Kouonon, Leonie C.; Jacquemart, Anne-Laure; Zoro Bi, Arsene I.; Bertin, Pierre; Baudoin, Jean-Pierre; Dje, Yao

2009-01-01

248

Molecular Identification of Mycobacterium avium subsp. silvaticum by Duplex High-Resolution Melt Analysis and Subspecies-Specific Real-Time PCR.  

PubMed

Accurate identification of mycobacterial species and subspecies is essential to evaluate their significance and to perform epidemiological studies. The subspecies of Mycobacterium avium have different attributes but coincide in their zoonotic potential. Our knowledge about M. avium subsp. silvaticum is limited, since its identification is uncertain. Mycobacterium avium subsp. avium and M. avium subsp. silvaticum can be discriminated from each other based only on phenotypic characteristics, as they have almost identical genome sequences. Here we describe the development of a diagnostic method which enables the molecular identification of M. avium subsp. silvaticum and discrimination from M. avium subsp. avium based on genomic differences in a duplex high-resolution melt and M. avium subsp. silvaticum-specific mismatch real-time PCR. The developed assay was tested on reference strains and 199 field isolates, which were analyzed by phenotypic methods previously. This assay not only identified all 63 M. avium subsp. silvaticum and 138 M. avium subsp. avium strains correctly but also enabled the detection of mixed M. avium subsp. avium-M. avium subsp. silvaticum cultures. This is the first time that such a large panel of strains has been analyzed, and we also report the first isolation of M. avium subsp. silvaticum from red fox, red deer, wild boar, cattle, and badger. This assay is reliable, rapid, simple, inexpensive, and robust. It eliminates the long-existing problem of ambiguous phenotypic identification and opens up the possibility for detailed and comprehensive strain studies. PMID:25740770

Rónai, Zsuzsanna; Csivincsik, Ágnes; Dán, Ádám

2015-05-01

249

Reclassification of Staphylococcus jettensis De Bel et al. 2013 as Staphylococcus petrasii subsp. jettensis subsp. nov. and emended description of Staphylococcus petrasii Pantucek et al. 2013.  

PubMed

The type and clinical strains of two recently described coagulase-negative species of the genus Staphylococcus, Staphylococcus petrasii and Staphylococcus jettensis, were compared using dnaJ, tuf, gap, hsp60 and rpoB gene sequences, DNA-DNA hybridization, ribotyping, repetitive sequence-based PCR fingerprinting and extensive biochemical characterization. Based on the results, the species description of S. petrasii has been emended and S. jettensis should be reclassified as a novel subspecies within S. petrasii for which the name Staphylococcus petrasii subsp. jettensis subsp. nov. is proposed. The type strain is SEQ110(T) (?=?LMG 26879(T)?=?CCUG 62657(T)?=?DSM 26618(T)?=?CCM 8494(T)). PMID:25261165

De Bel, Annelies; Švec, Pavel; Petráš, Petr; Sedlá?ek, Ivo; Pant??ek, Roman; Echahidi, Fedoua; Piérard, Denis; Vandamme, Peter

2014-12-01

250

Antioxidant Activity of the Essential Oils of Different Parts of Juniperus excelsa M. Bieb. subsp. excelsa and J. excelsa M. Bieb. subsp. polycarpos (K. Koch) Takhtajan (Cupressaceae)  

PubMed Central

The essential oils of branchlets and fruits of Juniperus excelsa subsp. excelsa and Juniperus excelsa subsp. polycarpos were examined for their antioxidant activity. The compositions of the essential oils were studied by GC and GC-MS. To evaluation the antioxidants activity of the volatile oils, pure components and positive controls at different concentrations, thin-layer chromatography (TLC) screening methods, diphenylpicrylhydrazyl (DPPH) assay, deoxyribose degradation test and modified deoxyribose degradation test were employed. The results of the present study demonstrate some antioxidant activity for the tested essential oils obtained from various parts of both plants. It indicates that the use of these essential oils, in very low concentrations, may be useful as a natural preservative. However before any final conclusion, it is suggested that the antioxidant activity of these oils should also be evaluated by using lipid solvent system methods. PMID:24250416

Emami, Sayyed Ahmad; Abedindo, Bibi Fatemeh; Hassanzadeh-Khayyat, Mohammad

2011-01-01

251

Bioprocessing of some agro-industrial residues for endoglucanase production by the new subsp.; Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J  

PubMed Central

The use of low cost agro-industrial residues for the production of industrial enzymes is one of the ways to reduce significantly production costs. Cellulase producing actinomycetes were isolated from soil and decayed agricultural wastes. Among them, a potential culture, strain NEAE-J, was selected and identified on the basis of morphological, cultural, physiological and chemotaxonomic properties, together with 16S rDNA sequence. It is proposed that strain NEAE-J should be included in the species Streptomyces albogriseolus as a representative of a novel sub-species, Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J and sequencing product was deposited in the GenBank database under accession number JN229412. This organism was tested for its ability to produce endoglucanase and release reducing sugars from agro-industrial residues as substrates. Sugarcane bagasse was the most suitable substrate for endoglucanase production. Effects of process variables, namely incubation time, temperature, initial pH and nitrogen source on production of endoglucanase by submerged fermentation using Streptomyces albogriseolus subsp. cellulolyticus have been studied. Accordingly optimum conditions have been determined. Incubation temperature of 30 °C after 6 days, pH of 6.5, 1% sugarcane bagasse as carbon source and peptone as nitrogen source were found to be the optimum for endoglucanase production. Optimization of the process parameters resulted in about 2.6 fold increase in the endoglucanase activity. Therefore, Streptomyces albogriseolus subsp. cellulolyticus coud be potential microorganism for the intended application. PMID:25242966

El-Naggar, Noura El-Ahmady; Abdelwahed, Nayera A.M.; Saber, Wesam I.A.; Mohamed, Asem A.

2014-01-01

252

Polyphasic taxonomic revision of the Ralstonia solanacearum species complex: proposal to emend the descriptions of Ralstonia solanacearum and Ralstonia syzygii and reclassify current R. syzygii strains as Ralstonia syzygii subsp. syzygii subsp. nov., R. solanacearum phylotype IV strains as Ralstonia syzygii subsp. indonesiensis subsp. nov., banana blood disease bacterium strains as Ralstonia syzygii subsp. celebesensis subsp. nov. and R. solanacearum phylotype I and III strains as Ralstonia pseudosolanacearum sp. nov.  

PubMed

The Ralstonia solanacearum species complex has long been recognized as a group of phenotypically diverse strains that can be subdivided into four phylotypes. Using a polyphasic taxonomic approach on an extensive set of strains, this study provides evidence for a taxonomic and nomenclatural revision of members of this complex. Data obtained from phylogenetic analysis of 16S-23S rRNA ITS gene sequences, 16S-23S rRNA intergenic spacer (ITS) region sequences and partial endoglucanase (egl) gene sequences and DNA-DNA hybridizations demonstrate that the R. solanacearum species complex comprises three genospecies. One of these includes the type strain of Ralstonia solanacearum and consists of strains of R. solanacearum phylotype II only. The second genospecies includes the type strain of Ralstonia syzygii and contains only phylotype IV strains. This genospecies is subdivided into three distinct groups, namely R. syzygii, the causal agent of Sumatra disease on clove trees in Indonesia, R. solanacearum phylotype IV strains isolated from different host plants mostly from Indonesia, and strains of the blood disease bacterium (BDB), the causal agent of the banana blood disease, a bacterial wilt disease in Indonesia that affects bananas and plantains. The last genospecies is composed of R. solanacearum strains that belong to phylotypes I and III. As these genospecies are also supported by phenotypic data that allow the differentiation of the three genospecies, the following taxonomic proposals are made: emendation of the descriptions of Ralstonia solanacearum and Ralstonia syzygii and descriptions of Ralstonia syzygii subsp. nov. (type strain R 001(T)?=?LMG 10661(T)?=?DSM 7385(T)) for the current R. syzygii strains, Ralstonia syzygii subsp. indonesiensis subsp. nov. (type strain UQRS 464(T)?=?LMG 27703(T)?=?DSM 27478(T)) for the current R. solanacearum phylotype IV strains, Ralstonia syzygii subsp. celebesensis subsp. nov. (type strain UQRS 627(T)?=?LMG 27706(T)?=?DSM 27477(T)) for the BDB strains and Ralstonia pseudosolanacearum sp. nov. (type strain UQRS 461(T)?=?LMG 9673(T)?=?NCPPB 1029(T)) for the strains of R. solanacearum phylotypes I and III. PMID:24944341

Safni, Irda; Cleenwerck, Ilse; De Vos, Paul; Fegan, Mark; Sly, Lindsay; Kappler, Ulrike

2014-09-01

253

Clavibacter michiganensis subsp. michiganensis Vatr1 and Vatr2 transcriptional regulators are required for virulence in tomato.  

PubMed

The plant pathogen Clavibacter michiganensis subsp. michiganensis is a gram-positive bacterium responsible for wilt and canker disease of tomato. Although disease development is well characterized and diagnosed, molecular mechanisms of C. michiganensis subsp. michiganensis virulence are poorly understood. Here, we identified and characterized two C. michiganensis subsp. michiganensis transcriptional regulators, Vatr1 and Vatr2, that are involved in pathogenicity of C. michiganensis subsp. michiganensis. Vatr1 and Vatr2 belong to TetR and MocR families of transcriptional regulators, respectively. Mutations in their corresponding genes caused attenuated virulence, with the ?vatr2 mutant showing a more dramatic effect than ?vatr1. Although both mutants grew well in vitro and reached a high titer in planta, they caused reduced wilting and canker development in infected plants compared with the wild-type bacterium. They also led to a reduced expression of the ethylene-synthesizing tomato enzyme ACC-oxidase compared with wild-type C. michiganensis subsp. michiganensis and to reduced ethylene production in the plant. Transcriptomic analysis of wild-type C. michiganensis subsp. michiganensis and the two mutants under infection-mimicking conditions revealed that Vatr1 and Vatr2 regulate expression of virulence factors, membrane and secreted proteins, and signal-transducing proteins. A 70% overlap between the sets of genes positively regulated by Vatr1 and Vatr2 suggests that these transcriptional regulators are on the same molecular pathway responsible for C. michiganensis subsp. michiganensis virulence. PMID:24940988

Savidor, Alon; Chalupowicz, Laura; Teper, Doron; Gartemann, Karl-Heinz; Eichenlaub, Rudolf; Manulis-Sasson, Shulamit; Barash, Isaac; Sessa, Guido

2014-10-01

254

Foliar application of biofilm formation-inhibiting compounds enhances control of citrus canker caused by Xanthomonas citri subsp. citri.  

PubMed

Citrus canker caused by the bacterium Xanthomonas citri subsp. citri is an economically important disease of citrus worldwide. Biofilm formation plays an important role in early infection of X. citri subsp. citri on host leaves. In this study, we assessed the hypothesis that small molecules inhibiting biofilm formation reduce X. citri subsp. citri infection and enhance the control of citrus canker disease. D-leucine and 3-indolylacetonitrile (IAN) were found to prevent biofilm formation by X. citri subsp. citri on different abiotic surfaces and host leaves at a concentration lower than the minimum inhibitory concentration (MIC). Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis indicated that IAN repressed expression of chemotaxis/motility-related genes in X. citri subsp. citri. In laboratory experiments, planktonic and biofilm cells of X. citri subsp. citri treated with D-leucine and IAN, either alone or in combination, were more susceptible to copper (CuSO4) than those untreated. In greenhouse assays, D-leucine and IAN applied alone or combined with copper reduced both the number of canker lesions and bacterial populations of X. citri subsp. citri on citrus host leaves. This study provides the basis for the use of foliar-applied biofilm inhibitors for the control of citrus canker alone or combined with copper-based bactericides. PMID:23901828

Li, Jinyun; Wang, Nian

2014-02-01

255

Divergent Immune Responses to Mycobacterium avium subsp. paratuberculosis Infection Correlate with Kinome Responses at the Site of Intestinal Infection  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease (JD) in cattle. M. avium subsp. paratuberculosis infects the gastrointestinal tract of calves, localizing and persisting primarily in the distal ileum. A high percentage of cattle exposed to M. avium subsp. paratuberculosis do not develop JD, but the mechanisms by which they resist infection are not understood. Here, we merge an established in vivo bovine intestinal segment model for M. avium subsp. paratuberculosis infection with bovine-specific peptide kinome arrays as a first step to understanding how infection influences host kinomic responses at the site of infection. Application of peptide arrays to in vivo tissue samples represents a critical and ambitious step in using this technology to understand host-pathogen interactions. Kinome analysis was performed on intestinal samples from 4 ileal segments subdivided into 10 separate compartments (6 M. avium subsp. paratuberculosis-infected compartments and 4 intra-animal controls) using bovine-specific peptide arrays. Kinome data sets clustered into two groups, suggesting unique binary responses to M. avium subsp. paratuberculosis. Similarly, two M. avium subsp. paratuberculosis-specific immune responses, characterized by different antibody, T cell proliferation, and gamma interferon (IFN-?) responses, were also observed. Interestingly, the kinomic groupings segregated with the immune response groupings. Pathway and gene ontology analyses revealed that differences in innate immune and interleukin signaling and particular differences in the Wnt/?-catenin pathway distinguished the kinomic groupings. Collectively, kinome analysis of tissue samples offers insight into the complex cellular responses induced by M. avium subsp. paratuberculosis in the ileum and provides a novel method to understand mechanisms that alter the balance between cell-mediated and antibody responses to M. avium subsp. paratuberculosis infection. PMID:23716614

Määttänen, Pekka; Trost, Brett; Scruten, Erin; Potter, Andrew; Kusalik, Anthony; Griebel, Philip

2013-01-01

256

Isolation of Mycobacterium avium subsp. paratuberculosis from Free-Ranging Birds and Mammals on Livestock Premises  

Microsoft Academic Search

Surveys for Mycobacterium avium subsp. paratuberculosis infection in free-ranging mammals and birds were conducted on nine dairy and beef cattle farms in Wisconsin and Georgia. Specimens were collected from 774 animals representing 25 mammalian and 22 avian species. Specimens of ileum, liver, intestinal lymph nodes, and feces were harvested from the larger mammals; a liver specimen and the gastrointestinal tract

Joseph L. Corn; Elizabeth J. B. Manning; Srinand Sreevatsan; John R. Fischer

2005-01-01

257

Detection of Mycobacterium avium subsp. paratuberculosis in Drinking Water and Biofilms Using Quantitative PCR  

EPA Science Inventory

Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne?s disease in domestic animals and has been implicated in Crohn?s disease in humans. Cows infected with Johne?s disease shed large quantities of MAP into soil. Further, MAP has been isolated from surface water, is resi...

258

Influence of the carbon source on nisin production in Lactococcus lactis subsp. lactis batch fermentations  

Microsoft Academic Search

Nisin production by Lactucmcus lrrctis subsp. lactis NIZO 22186 was studied in batch fermentation using a complex medium. Nisin production showed primary metabolite kinetics: nisin biosynthesis took place during the active growth phase and completely stopped when cells entered the stationary phase. A stringent correlation could be observed between the expression of the prenisin gene (nisA) and the synthesis of

LUC DE VUYST; ERICK J. VANDAMME

1992-01-01

259

VERTEBRATE TOXICOLOGY OF THE SOLUBILIZED PROTEINS OF BACILLUS THURINGIENSIS SUBSP. ISRAELENSIS  

EPA Science Inventory

This review summarizes the studies done with the mammalian toxic Bacillus thuringiensis subsp. israelensis (Bti) 28 kDa cytA protein. The data is relevant to hazard identification studies with bacterial pesticides. The data shows that cytA produces lethal physiological changes in...

260

Comparison of fecal DNA extraction kits for the detection of Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fecal culture is considered the gold standard for the diagnosis of paratuberculosis, however, PCR for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in fecal material is widely used today, having demonstrated great sensitivity and specificity. To insure the most efficient and rep...

261

INGESTION AND ADSORPTION OF 'BACILLUS THURINGIENSIS' SUBSP. 'ISRAELENSIS' BY 'GAMMARUS LACUSTRIS' IN THE LABORATORY  

EPA Science Inventory

Several groups of Gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of Bacillus thuringiensis subsp. israelensis per liter for 1- or 24-hour periods by using traditional static bioassay exposure procedures. The experiments verified that traditional exp...

262

NEW METHOD OF SEROLOGICAL TESTING FOR MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS (JOHNE'S DISEASE) BY FLOW CYTOMETRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Johne’s disease (JD) or paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is one of the most widespread and economically important diseases of livestock and wild ruminants worldwide. MAP has also been suspected as an etiologic agent of Crohn’s disease in humans. Attem...

263

Genome sequence of the enterobacterial phytopathogen Erwinia carotovora subsp. atroseptica and characterization of virulence factors  

Microsoft Academic Search

The bacterial family Enterobacteriaceae is notable for its well studied human pathogens, including Salmonella, Yersinia, Shigella, and Escherichia spp. However, it also contains several plant pathogens. We report the genome sequence of a plant pathogenic enterobacterium, Erwinia carotovora subsp. atroseptica (Eca) strain SCRI1043, the causative agent of soft rot and blackleg potato diseases. Approximately 33% of Eca genes are not

K. S. Bell; M. Sebaihia; L. Pritchard; M. T. G. Holden; L. J. Hyman; M. C. Holeva; N. R. Thomson; S. D. Bentley; L. J. C. Churcher; K. Mungall; R. Atkin; N. Bason; K. Brooks; T. Chillingworth; K. Clark; J. Doggett; A. Fraser; Z. Hance; H. Hauser; K. Jagels; S. Moule; H. Norbertczak; D. Ormond; C. Price; M. A. Quail; M. Sanders; D. Walker; S. Whitehead; G. P. C. Salmond; P. R. J. Birch; J. Parkhill; I. K. Toth

2004-01-01

264

Unraveling the Host Response to Mycobacterium avium subsp. paratuberculosis: One Thread at a Time  

Technology Transfer Automated Retrieval System (TEKTRAN)

The study of host immune responses to Mycobacterium avium subsp. paratuberculosis (MAP) is complicated by a number of factors, including the protracted nature of the disease and the stealthy nature of the pathogen. Improved tools for the measurement of immunologic responses in ruminant species, par...

265

Pathogenesis of Mycobacterium avium subsp. paratuberculosis in Neonatal Calves after Oral or Intraperitoneal Experimental Infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Understanding the infection process to Mycobacterium avium subsp. paratuberculosis is tantamount to the development of effective vaccines and therapeutics for the control of this disease in the field. The current study compared the effectiveness of oral and intraperitoneal methods of experimental in...

266

Experimental infection of a bovine model with human isolates of Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis (Map), the etiologic agent of Johne's disease (JD) in ruminants, has been implicated in the pathogenesis of Crohn's disease (CD) in humans. We developed a bovine ileal cannulation model to facilitate comparison of the immune response to Map and the mechanisms of pathogenesis in cattle and humans. Initial studies showed a T cannula could be maintained

Andrew J. Allen; Kun-Taek Park; George M. Barrington; Kevin K. Lahmers; Gaber S. Abdellrazeq; Heba M. Rihan; Srinand Sreevatsan; Christopher Davies; Mary J. Hamilton; William C. Davis

2011-01-01

267

No Holes Barred: Invasion of the Intestinal Mucosa by Mycobacterium avium subsp. paratuberculosis  

PubMed Central

The infection biology of Mycobacterium avium subsp. paratuberculosis has recently crystallized, with added details surrounding intestinal invasion. The involvement of pathogen-derived effector proteins such as the major membrane protein, oxidoreductase, and fibronectin attachment proteins have been uncovered. Mutations constructed in this pathogen have also shed light on genes needed for invasion. The host cell types that are susceptible to invasion have been defined, along with their transcriptional response. Recent details have given a new appreciation for the dynamic interplay between the host and bacterium that occurs at the outset of infection. An initial look at the global expression pathways of the host has shown a circumvention of the cell communication pathway by M. avium subsp. paratuberculosis, which loosens the integrity of the tight junctions. We now know that M. avium subsp. paratuberculosis activates the epithelial layer and also actively recruits macrophages to the site of infection. These notable findings are summarized along with added mechanistic details of the early infection model. We conclude by proposing critical next steps to further elucidate the process of M. avium subsp. paratuberculosis invasion. PMID:23940208

Bermudez, Luiz E.

2013-01-01

268

Mycobacterium avium Subsp. avium Infection in Four Veal Calves: Differentiation from Intestinal Tuberculosis  

PubMed Central

Mycobacterium avium subsp. avium (Maa) is an intracellular pathogen belonging to the Mycobacterium avium-intracellulare complex (MAC). Reservoirs of MAC are the natural environment, wildlife and domestic animals. In adult bovine, MAC infections are typically caused by Mycobacterium avium subsp. paratuberculosis (Map). Maa infections in bovine are rarely reported but may cause clinical disease and pathological lesions similar to those observed in paratuberculosis or those induced by members of the Mycobacterium tuberculosis complex (MTBC). Therefore, differentiation of MAC from MTBC infection should be attempted, especially if unusual mycobacterial lesions are encountered. Four veal calves from a fattening farm dying with clinical signs of otitis media, fever, and weight loss were submitted for necropsy. Samples from affected organs were taken for histologic investigation, bacteriologic culture, and bacterial specification using PCR. Macroscopic thickening of the intestinal mucosa was induced by granulomatous enteritis and colitis. Intracytoplasmic acid-fast bacteria were detected by Ziehl-Neelsen stains and PCR revealed positive results for Mycobacterium avium subsp. avium. Clinical and pathological changes of Maa infection in veal calves had features of Mycobacterium avium subsp. paratuberculosis and the MTBC. Therefore, Mycobacterium tuberculosis complex infection should be considered in cases of granulomatous enteritis in calves. PMID:24689051

Rossier, Christophe; Baehler, Corinne; Schmitt, Sarah

2014-01-01

269

Immunogenicity of Proteome-Determined Mycobacterium avium subsp. paratuberculosis-Specific Proteins in Sheep with Paratuberculosis?  

PubMed Central

Mycobacterium avium subsp. paratuberculosis causes paratuberculosis, a chronic granulomatous enteritis. Detecting animals with paratuberculosis infections is difficult because the currently available tools have low sensitivity and lack specificity; these tools are prone to generating spurious positive test results caused by exposure to environmental M. avium complex organisms. To generate candidate antigens for incorporation into a specific test for paratuberculosis, subspecies-specific proteins were determined by proteomic comparison of M. avium subsp. paratuberculosis and M. avium subsp. avium. Analysis was aimed at revealing proteins only expressed (or predominant) in the protein profile of M. avium subspecies paratuberculosis. Two-dimensional gel electrophoresis resolved approximately 1,000 protein spots from each subspecies. Proteome analysis identified protein spots whose expression profile appeared markedly increased in M. avium subsp. paratuberculosis, and 32 were identified by analysis of their tryptic peptide profile by matrix-assisted laser desorption ionization-time of flight analysis. Thirty of these proteins were cloned, and their recombinant proteins were expressed. Ovine paratuberculosis sera were used to assess their immunoreactivity by enzyme-linked immunosorbent assay (ELISA), Western blotting, and dot blot analysis. Seventeen proteins were detected in at least one of the immunoassays, and eleven proteins were detected by ELISA with an optical density in excess of the cutoff of 0.1 in four of six sera tested. The immunoreactivity of these proteins indicates their potential as unique diagnostic antigens for the development of a specific serological detection of paratuberculosis. PMID:18845834

Hughes, Valerie; Bannantine, John P.; Denham, Susan; Smith, Stuart; Garcia-Sanchez, Alfredo; Sales, Jill; Paustian, Michael L.; Mclean, Kevin; Stevenson, Karen

2008-01-01

270

Genetic analysis and antimicrobial susceptibility of Francisella noatunensis subsp. orientalis (sun. F. asiatica) isolates from fish  

Technology Transfer Automated Retrieval System (TEKTRAN)

Francisella noatunensis subsp. orientalis (syn. F. asiatica) (Fno) is an emergent fish pathogen that causes acute to chronic disease in a wide variety of freshwater, brackish and marine fish. Due to the emergent nature of this bacterium, established protocols to measure antimicrobial susceptibility ...

271

GENETIC DIVERSITY AMONG STRAINS OF ACIDOVORAX AVENAE SUBSP. CITRULLI IN CHINA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Acidovorax avenae subsp.citrulli (Aac), the causal agent of watermelon fruit blotch, was identified in watermelon in China in 2000 (T. Zhao et al., Acta Phytopathol. Sinica 4: 357-64. 2002). Although a considerable amount of watermelon and melon seed is produced in China, no information is availabl...

272

Rocket Immunoelectrophoresis of the Entomocidal Parasporal Crystal of Bacillus thuringiensis subsp. kurstaki†  

PubMed Central

Rocket immunoelectrophoresis was used to quantitate the soluble parasporal crystal of Bacillus thuringiensis subsp. kurstaki. The method described is rapid, reliable, specific, and extremely accurate, and it can be used to measure crystal toxin in commercial microbial insecticides that contain a mixture of spores, vegetative cells, and carrier materials. Images PMID:16345656

Andrews, R. E.; Iandolo, J. J.; Campbell, B. S.; Davidson, L. I.; Bulla, L. A.

1980-01-01

273

EFFECT OF REMOVAL OF THE CYTOLYTIC FACTOR OF 'BACILLUS THURINGIENSIS' SUBSP. 'ISRAELENSIS' ON MOSQUITO TOXICITY  

EPA Science Inventory

Solubilized crystal protein of Bacillus thuringiensis subsp. israelensis was fractionated by affinity chromotography using a monoclonal antibody directed against the crystal's 28 kDa peptide. The 28 kDa peptide ws found to be relatively nontoxic to mosquito larvae although it doe...

274

Optimization of hexadecylpyridinium chloride decontamination for culture of Mycobacterium avium subsp. paratuberculosis from milk  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cows in advanced stages of Johne’s disease shed Mycobacterium avium subsp. paratuberculosis (MAP) into both their milk and feces, allowing for transmission of the bacteria between animals. The objective of this study was to formulate an optimized protocol for the isolation of MAP from milk and colos...

275

Proteome of the phytopathogen Xanthomonas citri subsp. citri: a global expression profile  

Microsoft Academic Search

BACKGROUND: Citrus canker is a disease caused by Xantomonas citri subsp.citri (Xac), and has emerged as one of the major threats to the worldwide citrus crop because it affects all commercial citrus varieties, decreases the production and quality of the fruits and can spread rapidly in citrus growing areas. In this work, the first proteome of Xac was analyzed using

Márcia R Soares; Agda P Facincani; Rafael M Ferreira; Leandro M Moreira; Julio CF de Oliveira; Jesus A Ferro; Rogério Meneghini; Fábio C Gozzo

2010-01-01

276

Whole-genome sequencing of Salmonella enterica subsp. enterica serovar Cubana strains isolated from agricultural sources  

Technology Transfer Automated Retrieval System (TEKTRAN)

We report draft genomes of Salmonella enterica subsp. enterica Serovar Cubana strain CVM42234 isolated from chick feed in 2012 and Salmonella Cubana strain 76814 isolated from swine in 2004. The genome sizes are 4,975,046 and 4,936,251 base pairs, respectively....

277

Whole-Genome Sequencing of Salmonella enterica subsp. enterica Serovar Cubana Strains Isolated from Agricultural Sources.  

PubMed

We report the draft genomes of Salmonella enterica subsp. enterica serovar Cubana strain CVM42234, isolated from chick feed in 2012, and S. Cubana strain 76814, isolated from swine in 2004. The genome sizes are 4,975,046 and 4,936,251 bp, respectively. PMID:24459266

Benahmed, Faiza H; Gopinath, Gopal R; Wang, Hua; Jean-Gilles Beaubrun, Junia; Grim, Christopher; Cheng, Chorng-Ming; McClelland, Michael; Ayers, Sherry; Abbott, Jason; Desai, Prerak; Frye, Jonathan G; Weinstock, George; Hammack, Thomas S; Hanes, Darcy E; Rasmussen, Mark A; Davidson, Maureen K

2014-01-01

278

Whole-Genome Sequencing of Salmonella enterica subsp. enterica Serovar Cubana Strains Isolated from Agricultural Sources  

PubMed Central

We report the draft genomes of Salmonella enterica subsp. enterica serovar Cubana strain CVM42234, isolated from chick feed in 2012, and S. Cubana strain 76814, isolated from swine in 2004. The genome sizes are 4,975,046 and 4,936,251 bp, respectively. PMID:24459266

Benahmed, Faiza H.; Gopinath, Gopal R.; Wang, Hua; Jean-Gilles Beaubrun, Junia; Grim, Christopher; Cheng, Chorng-Ming; McClelland, Michael; Ayers, Sherry; Abbott, Jason; Desai, Prerak; Frye, Jonathan G.; Weinstock, George; Hammack, Thomas S.; Hanes, Darcy E.; Rasmussen, Mark A.

2014-01-01

279

Genome Sequence of the Clinical Isolate Staphylococcus aureus subsp. aureus Strain UAMS-1  

PubMed Central

We report here the draft genome sequence of Staphylococcus aureus subsp. aureus strain UAMS-1. UAMS-1 is a virulent oxacillin-susceptible clinical isolate. Its genome is composed of 2,763,963 bp and will be useful for further gene expression analysis using RNA sequencing (RNA-seq) technology. PMID:25676774

Sassi, Mohamed; Sharma, Deepak; Felden, Brice; Augagneur, Yoann

2015-01-01

280

Progress towards a commerical PCS-based seed assay for Acidovorax avenae subsp. citrulli  

Technology Transfer Automated Retrieval System (TEKTRAN)

To develop a commercial-scale PCR-based assay for Acidovorax. avenae subsp. citrulli in watermelon seed, parameters for immunomagnetic separation (IMS) were optimized. Optimal conditions for target cell recovery included 40 'g of polyclonal anti-AAC antibody per 108 immunomagnetic beads (IMBs) for ...

281

Inhibition of protein glycation by essential oils of branchlets and fruits of Juniperus communis subsp. hemisphaerica.  

PubMed

Oxidative stress and protein glycation play pivotal roles in the pathophysiology of diabetes mellitus and its vascular complications. The present study aimed to investigate the anti-glycation properties of essential oils obtained from different parts of Juniperus communis subsp. hemisphaerica. The branchlets of male tree (BMT) and branchlets of female (BFT) tree, and fruits of J. communis subsp. hemisphaerica were extracted using steam distillation method. The oils were phytochemically analyzed using gas chromatography-mass spectrometry. Anti-glycation properties were evaluated using hemoglobin and insulin glycation assays. Overall, 18 volatile components were identified in the J. communis subsp. hemisphaerica oils, amounting to 82.1%, 100.0% and 96.4% of the BMT, BFT and fruit oils, respectively. Promising inhibitory activity was observed from all concentrations of the tested oils in the hemoglobin and insulin glycation assays. The inhibitory activities peaked to 89.9% (BFT oil; 200 ?g mL(-1)) and 81.0% (BFT oil; 600 ?g mL(-1)) in the hemoglobin and insulin glycation assays, respectively. The evidence from this study suggests that essential oils obtained from the fruits and branchlets of J. communis subsp. hemisphaerica possess anti-glycation properties. These activities may find implication for the prevention and treatment of diabetic complications. PMID:25657787

Asgary, S; Naderi, G A; Shams Ardekani, M R; Sahebkar, A; Airin, A; Aslani, S; Kasher, T; Emami, S A

2014-01-01

282

Intraspecific chemical variability of the leaf essential oil of Juniperus phoenicea subsp. turbinata from Corsica  

Microsoft Academic Search

The composition of 50 samples of essential oil of individual plants of Juniperus phoenicea subsp. turbinata from Corsica was investigated by GC, GC–MS and 13C NMR. ?-Pinene, ?-phellandrene, ?-terpinyl acetate, ?-3-carene, myrcene and ?-phellandrene were found to be the main constituents. The results were submitted to cluster analysis and discriminant analysis which allowed two groups of essential oils to be

Serge Rezzi; Carlos Cavaleiro; Ange Bighelli; Ligia Salgueiro; António Proença da Cunha; Joseph Casanova

2001-01-01

283

Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds  

Technology Transfer Automated Retrieval System (TEKTRAN)

Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be the primary source of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-se...

284

Immunologic responses to Mycobacterium avium subsp. paratuberculois protein cocktail vaccines in a mouse model  

Technology Transfer Automated Retrieval System (TEKTRAN)

Johne’s disease is a chronic granulomatous enteritis characterized by severe diarrhea, wasting and a decline in milk production caused by the bacterium Mycobacterium avium subsp. paratuberculois (MAP). The vaccine currently on the market has some limitations including a severe injection site reactio...

285

Immunologic Responses to Mycobacterium avium subsp. paratuberculosis in Neonatal Calves After Oral or Intraperitoneal Experimental Infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Infection models are useful for studying host responses to infection to aid in the development of diagnostic tools and vaccines. The majority of experimental models for ruminants have utilized an oral inoculation of live Mycobacterium avium subsp. paratuberculosis (MAP) in order to establish infecti...

286

Induction of B Cell Responses Upon Experimental Infection of Neonatal Calves with Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Animal models are useful for studying host responses to infection and aid in the development of diagnostic tools and vaccines. The current study was designed to compare the effects of different methods of experimental infection: Oral (Mycobacterium avium subsp. parauberculosis (MAP) strain K-10; Or...

287

The Transport of Mycobacterium avium subsp. paratuberculosis through Saturated Aquifer Materials  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) is the causative agent of Johne’s disease, a chronic enteric infection causing diarrhea and wasting in cattle, sheep, and other ruminants. Because Johne’s disease is spread by the ingestion of M. paratuberculosis, a good understanding...

288

Scalp Abscess Due to Streptomyces cacaoi subsp. cacaoi, First Report in a Human Infection  

PubMed Central

Streptomyces cacaoi subsp. cacaoi, a Gram-positive, branching filamentous bacteria, was isolated from a scalp infection in a patient from Pondicherry, India. Phenotypic tests identified the isolate as a Streptomyces species, but 16S rRNA sequence analysis provided the species identification required for tracking of this emerging pathogen. PMID:22278841

Pellegrini, Gerald J.; Graziano, James C.; Ragunathan, Latha; Bhat, Malini A.; Hemashettar, Basavaraj M.

2012-01-01

289

Development of loop-mediated isothermal amplification for detection of Leifsonia xyli subsp. xyli in sugarcane  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ratoon stunt, caused by the xylem-limited coryneform bacterium Leifsonia xyli subsp. xyli (Lxx), is prevalent in most sugarcane-planting countries. Because the disease does not cause characteristic external symptoms, a laboratory-based technique is needed for accurate diagnosis. Based on loop-mediat...

290

Multilocus sequence typing reveals two evolutionary lineages of the watermelon pathogen, Acidovorax avenae subsp. citrulli  

Technology Transfer Automated Retrieval System (TEKTRAN)

Acidovorax avenae subsp. citrulli (Aac), the causal agent of bacterial blight and fruit blotch of watermelon and other cucurbits, has caused great damage to the watermelon and melon industry in China and the USA. Understanding the origin of this emerging disease is important for controlling outbrea...

291

Bartonella vinsonii subsp. berkhoffii and Bartonella henselae bacteremia in a father and daughter with neurological disease  

Microsoft Academic Search

BACKGROUND: Bartonella vinsonii subsp. berkhoffii is an important, emerging, intravascular bacterial pathogen that has been recently isolated from immunocompetent patients with endocarditis, arthritis, neurological disease and vasoproliferative neoplasia. Vector transmission is suspected among dogs and wild canines, which are the primary reservoir hosts. This investigation was initiated to determine if pets and family members were infected with one or more

Edward B Breitschwerdt; Ricardo G Maggi; Paul M Lantos; Christopher W Woods; Barbara C Hegarty; Julie M Bradley

2010-01-01

292

The nucleotide sequence of a carboxymethylcellulase gene from Pseudomonas fluorescens subsp. cellulosa  

Microsoft Academic Search

The complete nucleotide sequence of the gene coding for one of the carboxymethycellulases (CMCase), expressed by Pseudomonas fluorescens subsp. cellulosa, has been determined. The structural gene consists of an open reading frame, commencing with an ATG start codon, of 2886 base pairs followed by a TAA stop codon. The gene was shown to code for a signal peptide which closely

Judith Hall; Harry J. Gilbert

1988-01-01

293

Rapid Expression of Mycobacterium avium subsp. paratuberculosis Recombinant Proteins for Antigen Discovery  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease, a chronic granulo- matous enteritis of ruminants and other species. Detection of infection in animals is hampered by the lack of sensitive and specific diagnostic assays. We describe here an approach that utilizes translationally active PCR fragments for the rapid in vitro transcription and translation of recombinant proteins for

Lingling Li; Shirin Munir; John P. Bannantine; Srinand Sreevatsan; Sagarika Kanjilal; Vivek Kapur

2007-01-01

294

Rapid Expression of Mycobacterium avium subsp. paratuberculosis Recombinant Proteins for Antigen Discovery  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne’s disease, a chronic granulomatous enteritis of ruminants and other species. Detection of infection in animals is hampered by the lack of sensitive and specific diagnostic assays. We here describe an approach that utilizes t...

295

An improved assay for detection of Acidovorax avenae subsp. citrulli in watermelon and melon seed  

Technology Transfer Automated Retrieval System (TEKTRAN)

Acidovorax avenae subsp. citrulli (Aac), the causal agent of a watermelon seedling blight and fruit blotch (WFB), has emerged as a serious seedborne pathogen of watermelon, melons, pumpkin, and citron. Although attempts have been made to develop a simple routine laboratory seed assay to detect the...

296

Primary transcriptomes of Mycobacterium avium subsp. paratuberculosis reveal proprietary pathways in tissue and macrophages  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: Mycobacterium avium subsp. paratuberculosis persistently infect intestines and mesenteric lymph nodes leading to a prolonged subclinical disease. We investigated the intracellular lifestyle of MAP in the intestines and lymph nodes to understand the MAP pathways that function to govern th...

297

Scalp abscess due to Streptomyces cacaoi subsp. cacaoi, first report in a human infection.  

PubMed

Streptomyces cacaoi subsp. cacaoi, a Gram-positive, branching filamentous bacteria, was isolated from a scalp infection in a patient from Pondicherry, India. Phenotypic tests identified the isolate as a Streptomyces species, but 16S rRNA sequence analysis provided the species identification required for tracking of this emerging pathogen. PMID:22278841

Pellegrini, Gerald J; Graziano, James C; Ragunathan, Latha; Bhat, Malini A; Hemashettar, Basavaraj M; Brown, June M

2012-04-01

298

Envelope protein complexes of Mycobacterium avium subsp. paratuberculosis and their antigenicity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne’s disease, a chronic enteric disease of ruminant animals. In the present study, blue native PAGE electrophoresis and 2D SDS-PAGE were used to separate MAP envelope protein complexes, followed by mass spectrometry (MS) ...

299

Development of loop-mediated isothermal amplification for detection of Leifsonia xyli subsp. xyli in sugarcane  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ratoon stunt, caused by the xylem-limited coryneform bacterium Leifsonia xyli subsp. xyli (Lxx), is prevalent in most sugarcane-producing countries. Because the disease does not cause characteristic external symptoms, a laboratory-based technique is needed for accurate diagnosis. We developed a diag...

300

Bioaccessible Antioxidants in Milk Fermented by Bifidobacterium longum subsp. longum Strains  

PubMed Central

Bifidobacterium longum subsp. longum is among the dominant species of the human gastrointestinal microbiota and could thus have potential as probiotics. New targets such as antioxidant properties have interest for beneficial effects on health. The objective of this study was to evaluate the bioaccessibility of antioxidants in milk fermented by selected B. longum subsp. longum strains during in vitro dynamic digestion. The antioxidant capacity of cell extracts from 38 strains, of which 32 belong to B. longum subsp. longum, was evaluated with the ORAC (oxygen radical absorbance capacity) method. On the basis of screening and gene sequence typing by multilocus locus sequence analysis (MLSA), five strains were chosen for fermenting reconstituted skim milk. Antioxidant capacity varied among the strains tested (P = 0.0009). Two strains of B. longum subsp. longum (CUETM 172 and 171) showed significantly higher ORAC values than the other bifidobacteria strains. However, there does not appear to be a relationship between gene sequence types and antioxidant capacity. The milk fermented by each of the five strains selected (CUETM 268, 172, 245, 247, or PRO 16-10) did not have higher initial ORAC values compared to the nonfermented milk samples. However, higher bioaccessibility of antioxidants in fermented milk (175–358%) was observed during digestion. PMID:25802836

Gagnon, Mérilie; Savard, Patricia; Rivière, Audrey; LaPointe, Gisèle

2015-01-01

301

Molecular markers to determine ecological fate of Bacillus thuringiensis subsp. kurstaki  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacillus thuringiensis (“Bt”) is a ubiquitous soil bacterium with entomopathogenic properties. One strain, Bt subsp. kurstaki (“Btk”), is highly toxic to lepidopteran larvae and used in many commercial products for biological pest control. We designed a set of DNA markers that successfully identifi...

302

Experimental Infection of White-tailed Deer (Odocoileus virginianus) with Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (Map) is the causative agent of paratuberculosis or Johne’s disease, a chronic enteric disease of domestic ruminants as well as some non-domestic ruminants. Paratuberculosis is characterized by a protracted subclinical phase followed by clinical signs such...

303

Host physiological condition regulates parasitic plant performance: Arceuthobium vaginatum subsp. cryptopodum on Pinus ponderosa  

Microsoft Academic Search

Much research has focused on effects of plant parasites on host-plant physiology and growth, but little is known about effects of host physiological condition on parasite growth. Using the parasitic dwarf mistletoe Arceuthobium vaginatum subsp. cryptopodum (Viscaceae) and its host Pinus ponderosa, we investigated whether changes in host physiological condition influenced mistletoe shoot development in northern Arizona forests. We conducted

Christopher P. Bickford; Thomas E. Kolb; Brian W. Geils

2005-01-01

304

Exploring the strain-specific attachment of Leuconostoc gelidum subsp. gasicomitatum on food contact surfaces.  

PubMed

The psychrotrophic lactic acid bacterium (LAB) Leuconostoc gelidum subsp. gasicomitatum has emerged as one of the most prevalent specific spoilage organisms (SSOs) of packaged, cold-stored food products in Northern Europe. The whole genome sequencing of the type strain L. gelidum subsp. gasicomitatum LMG 18811(T) revealed genes encoding for proteins related to adhesion. In the present study the attachment of six food and environmental isolates was monitored on stainless steel (SS) and glass surfaces incubated (7°C for 5-9days) in two food simulating substrates (i.e. sweet bell pepper juice and boiled eggs in brine). The selection encompassed unique genotypes, isolated from different food products or sampling sites as well as slime-forming biotypes. The evaluation of the attached cells was performed with the bead vortexing method and a viability staining assay coupled with epifluorescence microscopy. On SS surfaces the slime-formers showed the lowest attachment (3.3-4.5logCFU/cm(2)), while strain L. gelidum subsp. gasicomitatum ab2, which was isolated from an acetic acid bath in a vegetable salad company, reached significantly higher populations of attached cells exceeding 7logCFU/cm(2). Strain ab2 formed dense cell aggregations on SS after 9days of incubation in sweet bell pepper juice. The attachment ability of L. gelidum subsp. gasicomitatum on surfaces documented in the present study extends our knowledge and understanding of the spoilage potential and intra-subspecies diversity of this microbe. PMID:25625910

Pothakos, Vasileios; Aulia, Yosi Ayu; Van der Linden, Inge; Uyttendaele, Mieke; Devlieghere, Frank

2015-04-16

305

Reproductive ecology of the Australian herb Trachymene incisa subsp.?incisa (Apiaceae)  

Microsoft Academic Search

Within the Apiaceae, subtle variation in reproductive characters such as dichogamy, pollinator specificity and umbel density may cause cryptic specialisation and be responsible for the diversity of life histories and gender expression in the family. To address the paucity of information for Australian species we investigated the reproductive ecology of the native perennial herb, Trachymene incisa Rudge subsp. incisa. T.

Yvonne C. DavilaA; Glenda M. Wardle

2002-01-01

306

Analysis of the Immune Response to Mycobacterium avium subsp. paratuberculosis in Experimentally Infected Calves  

Microsoft Academic Search

Johne's disease of cattle is widespread and causes significant economic loss to producers. Control has been hindered by limited understanding of the immune response to the causative agent, Mycobacterium avium subsp. paratuberculosis, and lack of an effective vaccine and sensitive specific diagnostic assays. The present study was conducted to gain insight into factors affecting the immune response to M. avium

Hye Cheong Koo; Yong Ho Park; Mary Jo Hamilton; George M. Barrington; Christopher J. Davies; Jong Bae Kim; John L. Dahl; W. Ray Waters; William C. Davis

2004-01-01

307

Functional Characterization of Iron Dependent Regulator (IdeR) of Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study we investigated an iron dependent regulator (IdeR) of Mycobacterium avium subsp. paratuberculosis (MAP). IdeR is a transcriptional factor that plays a global iron regulatory role in Mycobacterium tuberculosis (MTB) with a 19-bp recognition sequence. IdeR recognition sites within MAP ge...

308

Comparison of fecal DNA extraction kits for the detection of Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fecal culture is considered the gold standard for the diagnostics of paratuberculosis, however, PCR for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in fecal material is widely used today, having demonstrated great sensitivity and specificity. To insure the most efficient and r...

309

DETECTION OF BOVINE MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS IN CLINICAL AND ENVIRONMENTAL SAMPLES FROM AN INFECTED ANIMAL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Introduction: Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) causes Johne’s disease, a chronic, enteric infection that is passed from adults to calves via the fecal-oral route. Eradication of M. paratuberculosis from infected farms has been difficult and is likely due to long-ter...

310

Induction of B Cell Responses upon Experimental Infection of Neonatal Calves with Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Animal models are useful for studying host responses to infection and aid in the development of diagnostic tools and vaccines. The current study was designed to compare the effects of different methods of experimental infection: Oral (Mycobacterium avium subsp. parauberculosis (MAP) strain K-10; Or...

311

Survival of Mycobacterium avium subsp. paratuberculosis in Biofilms on Livestock Watering Trough Materials  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) is the causative agent of Johne’s disease, a chronic enteric infection that affects ruminants. Despite the ubiquitous occurrence of Mycobacterium sp. in nature and the fact that Johne’s disease has been reported worldwide, little rese...

312

Surface Proteome of “Mycobacterium avium subsp. hominissuis” during the Early Stages of Macrophage Infection  

PubMed Central

“Mycobacterium avium subsp. hominissuis” is a robust and pervasive environmental bacterium that can cause opportunistic infections in humans. The bacterium overcomes the host immune response and is capable of surviving and replicating within host macrophages. Little is known about the bacterial mechanisms that facilitate these processes, but it can be expected that surface-exposed proteins play an important role. In this study, the selective biotinylation of surface-exposed proteins, streptavidin affinity purification, and shotgun mass spectrometry were used to characterize the surface-exposed proteome of M. avium subsp. hominissuis. This analysis detected more than 100 proteins exposed at the bacterial surface of M. avium subsp. hominissuis. Comparisons of surface-exposed proteins between conditions simulating early infection identified several groups of proteins whose presence on the bacterial surface was either constitutive or appeared to be unique to specific culture conditions. This proteomic profile facilitates an improved understanding of M. avium subsp. hominissuis and how it establishes infection. Additionally, surface-exposed proteins are excellent targets for the host adaptive immune system, and their identification can inform the development of novel treatments, diagnostic tools, and vaccines for mycobacterial disease. PMID:22392927

McNamara, Michael; Tzeng, Shin-Cheng; Maier, Claudia; Zhang, Li

2012-01-01

313

Molecular Epidemiology of Mycobacterium avium subsp. paratuberculosis in a Longitudinal Study of Three Dairy Herds  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to evaluate whether cows that were low shedders of Mycobacterium avium subsp. paratuberculosis (MAP) were passive shedding animals or whether they were truly infected with MAP. We also evaluated whether these MAP-infected animals could have been infected as adults by ...

314

Genome Sequence of Lactococcus lactis subsp. lactis NCDO 2118, a GABA-Producing Strain  

PubMed Central

Lactococcus lactis subsp. lactis NCDO 2118 is a nondairy lactic acid bacterium, a xylose fermenter, and a gamma-aminobutyric acid (GABA) producer isolated from frozen peas. Here, we report the complete genome sequence of L. lactis NCDO 2118, a strain with probiotic potential activity. PMID:25278529

Oliveira, Letícia C.; Saraiva, Tessália D. L.; Soares, Siomar C.; Ramos, Rommel T. J.; Sá, Pablo H. C. G.; Carneiro, Adriana R.; Miranda, Fábio; Freire, Matheus; Renan, Wendel; Júnior, Alberto F. O.; Santos, Anderson R.; Pinto, Anne C.; Souza, Bianca M.; Castro, Camila P.; Diniz, Carlos A. A.; Rocha, Clarissa S.; Mariano, Diego C. B.; de Aguiar, Edgar L.; Folador, Edson L.; Barbosa, Eudes G. V.; Aburjaile, Flavia F.; Gonçalves, Lucas A.; Guimarães, Luís C.; Azevedo, Marcela; Agresti, Pamela C. M.; Silva, Renata F.; Tiwari, Sandeep; Almeida, Sintia S.; Hassan, Syed S.; Pereira, Vanessa B.; Abreu, Vinicius A. C.; Pereira, Ulisses P.; Dorella, Fernanda A.; Carvalho, Alex F.; Pereira, Felipe L.; Leal, Carlos A. G.; Figueiredo, Henrique C. P.; Silva, Artur; Miyoshi, Anderson

2014-01-01

315

Review of Mycobacterium avium subsp. paratuberculosis antigen candidates with diagnostic potential  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis (MAP) is a slow growing bacterium that can infect ruminants and remain latent for years without development of any clinical signs or disease. Diagnosis is often based on detection of MAP antibodies in milk or serum samples or culture of bacteria from faeces; however, these diagnostic tools are often not applicable until years after infection. Detection

Heidi Mikkelsen; Claus Aagaard; Søren Saxmose Nielsen; Gregers Jungersen

2011-01-01

316

Zur Blütenmorphologie und Bestäubungsökologie von Veratrum album subsp. lobelianum (Bernh.)Rchb  

Microsoft Academic Search

Zusammenfassung BeiVeratrum album subsp.lobelianum (Bernh.)Rchb. wurden im Gebirge Krkonoše (Riesengebirge) Blütenbau, Blütedauer und Blühverlauf studiert; besondere Berücksichtigung fanden dabei Vorkommen von Zwitterblüten und eingeschlechtlichen Blüten, Bau des Nektariums, Art und Weise der Nektarsekretion, Funktionsdauer der Narbe und Absinken der Keimfähigkeit des Pollens während der Anthese.

Erich Daumann

1967-01-01

317

Reducing the Bitterness of Tuna (Euthynnus pelamis) Dark Meat with Lactobacillus casei subsp. casei ATCC 393  

Microsoft Academic Search

Summary During the process of canning tuna fish, considerable amounts of dark tuna meat are left over because of its bitterness, which are then used in the production of animal food. Fermentation with Lactobacillus casei subsp. casei ATCC 393 was used as an alternative to reduce this bitter taste. Samples of meat were prepared, vacuum packed and then stored at

Fabiano Cleber Bertoldi; Ernani S. Sant; Luiz H. Beirão

318

Continuous production ofl-lactic acid from whey permeate by immobilized Lactobacillus casei subsp. casei  

Microsoft Academic Search

The production of l-lactic acid from whey permeate, a waste product of the dairy industry, by fermentation with the lactic acid bacterium Lactobacillus casei subsp. casei was investigated. A fermentation medium consisting of permeate and supplements, which enables exponential growth of the organisms, was developed. A fast method for determination of free and immobilized biomass in solid-rich media, based on

Wolfgang Krischke; Martin Schröder; Walter Trösch

1991-01-01

319

Iron-sparing Response of Mycobacterium avium subsp. paratuberculosis is Strain Dependent  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: Two genotypically and microbiologically distinct strains of Mycobacterium avium subsp. paratuberculosis (MAP) exist – the type I and type II strains that primarily infect sheep and cattle, respectively. Concentration of iron in the cultivation medium has been suggested as one contributin...

320

Intraspecific variability of the essential oil of Calamintha nepeta subsp. nepeta from Southern Italy (Apulia).  

PubMed

The essential oil of 46 spontaneous plants of Calamintha nepeta (L.) Savi subsp. nepeta growing wild in Sud, Italy (Salento, Apulia), were investigated by GC/MS. Fifty-seven components were identified in the oil representing over the 98% of the total oil composition. Four chemotypes were identified: piperitone oxide, piperitenone oxide, piperitone-menthone and pulegone. PMID:22646908

Negro, C; Notarnicola, S; De Bellis, L; Miceli, A

2013-03-01

321

Identification of resistance to Acidovorax avenae subsp. citrulli among melon (Cucumis spp.) Plant Introductions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial fruit blotch (BFB) caused by the bacterium Acidovorax avenae subsp. citrulli (Aac) is a seed-borne disease that threatens most cucurbit crops. Although, limited resistance has been found in a small number of Plant Introductions (PI) in watermelon (Citrullus spp.), no significant activity ...

322

Development and Application of a Multilocus Sequence Typing Scheme for Streptococcus gallolyticus subsp. gallolyticus  

PubMed Central

Streptococcus gallolyticus subsp. gallolyticus (formerly known as S. bovis biotype I) is a commensal of the gastrointestinal tract in animals and in up to 15% of healthy humans. Furthermore, it is a facultative pathogen that can cause infectious endocarditis, mastitis, and septicemia. The number of infections is increasing, but the transmission routes and zoonotic potential remain unknown. To assess the zoonotic potential and characterize the epidemiological structure of S. gallolyticus subsp. gallolyticus, we established a multilocus sequence typing (MLST) scheme. We amplified and sequenced internal fragments of seven housekeeping genes. The resulting sequences were analyzed with BioNumerics software 6.6 by using the unweighted-pair group method using average linkages algorithm. A total of 101 S. gallolyticus subsp. gallolyticus strains isolated from animals, humans, and environmental samples were analyzed and divided into 50 sequence types. Our first results highlight the importance of this MLST scheme for investigating the epidemiology, transmission patterns, and infection chains of S. gallolyticus subsp. gallolyticus. PMID:24789199

Dumke, J.; Hinse, D.; Vollmer, T.; Knabbe, C.

2014-01-01

323

Survival of Mycobacterium avium subsp. paratuberculosis in Biofilms on Livestock Watering Trough Materials  

Technology Transfer Automated Retrieval System (TEKTRAN)

Despite the ubiquitous occurrence of Mycobacterium sp. in nature and the fact that Johne’s disease has been reported worldwide, little research has been done to assess the survival of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) in agricultural environments. The goal of this stu...

324

Purification of native HBHA from Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Background Paratuberculosis remains today a major global problem in animal health, especially for dairy cattle. However, the diagnosis of its etiologic agent, Mycobacterium avium subsp. paratuberculosis (Map), still lacks sensitivity because of the lack of available antigens. Little is known about the virulence factors for this pathogen. In this study we have developed a method to produce and purify the heparin-binding hemagglutinin (HBHA), a major adhesin of Mycobacteria, from a culture of Map. Findings For this extremely slow-growing Mycobacterium, a culture was established in a 3-liter bioreactor. Using the bioreactor the amount of the Map biomass was increased 5-fold compared to a classical culture in flasks. The map-HBHA was purified from a Map lysate by heparin-Sepharose chromatography on HiTrap columns. Binding of map-HBHA onto heparin-Sepharose can be reduced in the presence of salt. Consequently, all steps of sample preparation and column equilibration were carried out in 20 mM Tris–HCl (pH 7.2). The map-HBHA was eluted by a linear NaCl gradient. High resolution mass spectrometry analyses revealed that the native form of map-HBHA has posttranslational modifications, including the removal of the initiation methionine, acetylation of the alanine residue at the N-terminal extremity and the presence of methylated lysines in the C-terminal domain of the protein. Conclusions An optimized culture of Map in a bioreactor was established to purify the native map-HBHA from a Map lysate by heparin-Sepharose chromatography. The availability of this antigen offers the possibility to study the structure of the protein and to examine its role in pathogenicity, in particular to better understand the specific interactions of Map with the intestinal tissue. The map-HBHA obtained in its native immunogenic form may also be useful to improve the diagnostic test, especially for the development of a new T-cell-based interferon gamma release assays. PMID:23390963

2013-01-01

325

Fortunella margarita Transcriptional Reprogramming Triggered by Xanthomonas citri subsp. citri  

PubMed Central

Background Citrus canker disease caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc) has become endemic in areas where high temperature, rain, humidity, and windy conditions provide a favourable environment for the dissemination of the bacterium. Xcc is pathogenic on many commercial citrus varieties but appears to elicit an incompatible reaction on the citrus relative Fortunella margarita Swing (kumquat), in the form of a very distinct delayed necrotic response. We have developed subtractive libraries enriched in sequences expressed in kumquat leaves during both early and late stages of the disease. The isolated differentially expressed transcripts were subsequently sequenced. Our results demonstrate how the use of microarray expression profiling can help assign roles to previously uncharacterized genes and elucidate plant pathogenesis-response related mechanisms. This can be considered to be a case study in a citrus relative where high throughput technologies were utilized to understand defence mechanisms in Fortunella and citrus at the molecular level. Results cDNAs from sequenced kumquat libraries (ESTs) made from subtracted RNA populations, healthy vs. infected, were used to make this microarray. Of 2054 selected genes on a customized array, 317 were differentially expressed (P < 0.05) in Xcc challenged kumquat plants compared to mock-inoculated ones. This study identified components of the incompatible interaction such as reactive oxygen species (ROS) and programmed cell death (PCD). Common defence mechanisms and a number of resistance genes were also identified. In addition, there were a considerable number of differentially regulated genes that had no homologues in the databases. This could be an indication of either a specialized set of genes employed by kumquat in response to canker disease or new defence mechanisms in citrus. Conclusion Functional categorization of kumquat Xcc-responsive genes revealed an enhanced defence-related metabolism as well as a number of resistant response-specific genes in the kumquat transcriptome in response to Xcc inoculation. Gene expression profile(s) were analyzed to assemble a comprehensive and inclusive image of the molecular interaction in the kumquat/Xcc system. This was done in order to elucidate molecular mechanisms associated with the development of the hypersensitive response phenotype in kumquat leaves. These data will be used to perform comparisons among citrus species to evaluate means to enhance the host immune responses against bacterial diseases. PMID:22078099

2011-01-01

326

Isolation of Mycobacterium avium subsp. paratuberculosis from free-ranging birds and mammals on livestock premises.  

PubMed

Surveys for Mycobacterium avium subsp. paratuberculosis infection in free-ranging mammals and birds were conducted on nine dairy and beef cattle farms in Wisconsin and Georgia. Specimens were collected from 774 animals representing 25 mammalian and 22 avian species. Specimens of ileum, liver, intestinal lymph nodes, and feces were harvested from the larger mammals; a liver specimen and the gastrointestinal tract were harvested from birds and small mammals. Cultures were performed by using radiometric culture and acid-fast isolates were identified by 16S/IS900/IS1311 PCR and mycobactin dependency characteristics. M. avium subsp. paratuberculosis was cultured from tissues and feces from 39 samples from 30 animals representing nine mammalian and three avian species. The prevalence of infected wild animals by premises ranged from 2.7 to 8.3% in Wisconsin and from 0 to 6.0% in Georgia. Shedding was documented in seven (0.9%) animals: three raccoons, two armadillos, one opossum, and one feral cat. The use of two highly polymorphic short sequence repeat loci for analysis of 29 of the 39 strains identified 10 alleles. One allelic pattern broadly shared in domestic ruminants ("7,5") appeared in approximately one-third of the wildlife M. avium subsp. paratuberculosis isolates studied. Given the few cases of shedding by free-ranging animals compared to the volume of contaminated manure produced by infected domestic ruminant livestock, contamination of the farm environment by infected wildlife was negligible. Wildlife may, however, have epidemiological significance for farms where M. avium subsp. paratuberculosis recently has been eliminated or on farms free of M. avium subsp. paratuberculosis but located in the geographic vicinity of farms with infected livestock. PMID:16269731

Corn, Joseph L; Manning, Elizabeth J B; Sreevatsan, Srinand; Fischer, John R

2005-11-01

327

Isolation of Mycobacterium avium subsp. paratuberculosis from Free-Ranging Birds and Mammals on Livestock Premises  

PubMed Central

Surveys for Mycobacterium avium subsp. paratuberculosis infection in free-ranging mammals and birds were conducted on nine dairy and beef cattle farms in Wisconsin and Georgia. Specimens were collected from 774 animals representing 25 mammalian and 22 avian species. Specimens of ileum, liver, intestinal lymph nodes, and feces were harvested from the larger mammals; a liver specimen and the gastrointestinal tract were harvested from birds and small mammals. Cultures were performed by using radiometric culture and acid-fast isolates were identified by 16S/IS900/IS1311 PCR and mycobactin dependency characteristics. M. avium subsp. paratuberculosis was cultured from tissues and feces from 39 samples from 30 animals representing nine mammalian and three avian species. The prevalence of infected wild animals by premises ranged from 2.7 to 8.3% in Wisconsin and from 0 to 6.0% in Georgia. Shedding was documented in seven (0.9%) animals: three raccoons, two armadillos, one opossum, and one feral cat. The use of two highly polymorphic short sequence repeat loci for analysis of 29 of the 39 strains identified 10 alleles. One allelic pattern broadly shared in domestic ruminants (“7,5”) appeared in approximately one-third of the wildlife M. avium subsp. paratuberculosis isolates studied. Given the few cases of shedding by free-ranging animals compared to the volume of contaminated manure produced by infected domestic ruminant livestock, contamination of the farm environment by infected wildlife was negligible. Wildlife may, however, have epidemiological significance for farms where M. avium subsp. paratuberculosis recently has been eliminated or on farms free of M. avium subsp. paratuberculosis but located in the geographic vicinity of farms with infected livestock. PMID:16269731

Corn, Joseph L.; Manning, Elizabeth J. B.; Sreevatsan, Srinand; Fischer, John R.

2005-01-01

328

Exopolysaccharide Expression in Lactococcus lactis subsp. cremoris Ropy352: Evidence for Novel Gene Organization?  

PubMed Central

Lactococcus lactis subsp. cremoris Ropy352 produces two distinct heteropolysaccharides, phenotypically described as ropy and mucoid, when cultured in nonfat milk. One exopolysaccharide precipitated with 50% ethanol as a series of elongated threads and was composed of glucose and galactose in a molar ratio of 3:2. The second exopolysaccharide precipitated with 75% ethanol as a fine flocculant and consisted of galactose, glucose, and mannose with a molar ratio of 67:21:12. A mutant strain, L. lactis subsp. cremoris EK240, lacking the ropy phenotype did not produce the exopolysaccharide that precipitated with 50% ethanol; however, it produced the exopolysaccharide that precipitated with 75% ethanol, indicating that the former exopolysaccharide is essential for the ropy phenotype. Cultures of L. lactis subsp. cremoris Ropy352 in 10% nonfat milk reached a viscosity of 25 Pa-s after 24 h, while those of the nonropy L. lactis subsp. cremoris EK240 mutant did not change. A mutation abolishing ropy exopolysaccharide expression mapped to a region on a plasmid containing two open reading frames, epsM and epsN, encoding novel glycosyltransferases bordered by ISS1 elements oriented in the same direction. Sequencing of this plasmid revealed two other regions involved in exopolysaccharide expression, an operon located between partial IS981 and IS982 elements, and an independent gene, epsU. Two and possibly three of these regions are involved in L. lactis subsp. cremoris Ropy352 exopolysaccharide expression and are arranged in a novel fashion different from that of typical lactococcal exopolysaccharide loci, and this provides genetic evidence for exopolysaccharide gene reorganization and evolution in Lactococcus. PMID:17122391

Knoshaug, Eric P.; Ahlgren, Jeff A.; Trempy, Janine E.

2007-01-01

329

Mycobacterium avium subsp. paratuberculosis fibronectin attachment protein facilitates M-cell targeting and invasion through a fibronectin bridge with host integrins.  

PubMed

Efficient attachment and ingestion of Mycobacterium avium subsp. paratuberculosis by cultured epithelial cells requires the expression of a fibronectin (FN) attachment protein homologue (FAP-P) which mediates FN binding by M. avium subsp. paratuberculosis. Invasion of Peyer's patches by M. avium subsp. paratuberculosis occurs through M cells, which, unlike other intestinal epithelial cells, express integrins on their luminal faces. We sought to determine if the interaction between FAP-P of M. avium subsp. paratuberculosis and soluble FN enabled targeting and invasion of M cells by M. avium subsp. paratuberculosis in vivo via these surface integrins. Wild-type and antisense FAP-P mutant M. avium subsp. paratuberculosis strains were injected alone or coinjected with blocking peptides or antibodies into murine gut loops, and immunofluorescence microscopy was performed to assess targeting and invasion of M cells by M. avium subsp. paratuberculosis. Nonopsonized M. avium subsp. paratuberculosis preferentially invaded M cells in murine gut loops. M-cell invasion was enhanced 2.6-fold when M. avium subsp. paratuberculosis was pretreated with FN. Invasion of M cells by the antisense FAP-P mutant of M. avium subsp. paratuberculosis was reduced by 77 to 90% relative to that observed for the control strains. Peptides corresponding to the RGD and synergy site integrin recognition regions of FN blocked M. avium subsp. paratuberculosis invasion of M cells by 75 and 45%, respectively, whereas the connecting segment 1 peptide was noninhibitory. Antibodies against the alpha5, alphaV, beta1, and beta3 integrin subunits inhibited M-cell invasion by 52 to 73%. The results indicate that targeting and invasion of M cells by M. avium subsp. paratuberculosis in vivo is mediated primarily by the formation of an FN bridge formed between FAP-P of M. avium subsp. paratuberculosis and integrins on M cells. PMID:15213112

Secott, T E; Lin, T L; Wu, C C

2004-07-01

330

Draft Genome Sequence of Salmonella enterica subsp. enterica Serotype Saintpaul Strain S-70, Isolated from an Aquatic Environment  

PubMed Central

Salmonella is a pathogen of worldwide importance, causing disease in a vast range of hosts, including humans. We report the genome sequence of Salmonella enterica subsp. enterica serotype Saintpaul strain S-70, isolated from an aquatic environment. PMID:24336367

Estrada-Acosta, Mitzi; Medrano-Félix, Andrés; Jiménez, Maribel; Gómez-Gil, Bruno; León-Félix, Josefina; Amarillas, Luis

2013-01-01

331

Osteopontin Immunoreactivity in the Ileum and Ileoceccal Lymph Node of Dairy Cows Naturally Infected with Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Osteopontin (Opn), a highly acidic glycoprotein, promotes cellular adhesion and recruitment and has been shown to be upregulated in the granulomas of mycobacterial infections. Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is associated with granulomatous enteritis. ...

332

Evaluation of Control Points in Youngstock and Adult Dairy Cow Management to Control Transmission of Mycobacterium avium subsp. paratuberculosis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Complete a series of prospective controlled on-farm trials to critically evaluate the efficacy and cost-benefit of commonly recommended management practices for reducing the transmission of Mycobacterium avium subsp. paratuberculosis (Map) in youngstock in infected herds....

333

Effects of seasonal heat stress on the diagnosis of Mycobacterium avium subsp. paratuberculosis in Texas dairy cattle  

E-print Network

variability in serological response to Mycobacterium avium subsp. paratuberculosis that is directly related to heat stress. We further hypothesized that a reciprocal response may occur during periods of heat stress that results in a greater risk of fecal...

Strickland, Summer J.

2005-11-01

334

Contrasting Results of Culture-Dependent and Molecular Analyses of Mycobacterium avium subsp. paratuberculosis from Wood Bison  

PubMed Central

Reduced to near extinction in the late 1800s, a number of wood bison populations (Bison bison athabascae) have been re-established through reintroduction initiatives. Although an invaluable tool for conservation, translocation of animals can spread infectious agents to new areas or expose animals to pathogens in their new environment. Mycobacterium avium subsp. paratuberculosis, a bacterium that causes chronic enteritis in ruminants, is among the pathogens of potential concern for wood bison management and conservation. In order to inform translocation decisions, our objectives were to determine the M. avium subsp. paratuberculosis infection status of wood bison herds in Canada and to culture and genetically characterize the infective strain(s). We tested fecal samples from bison (n = 267) in nine herds using direct PCR for three M. avium subsp. paratuberculosis-specific genetic targets with different copy numbers within the M. avium subsp. paratuberculosis genome. Restriction enzyme analysis (REA) and sequencing of IS1311 were performed on seven samples from five different herds. We also evaluated a panel of different culture conditions for their ability to support M. avium subsp. paratuberculosis growth from feces and tissues of direct-PCR-positive animals. Eighty-one fecal samples (30%) tested positive using direct IS900 PCR, with positive samples from all nine herds; of these, 75% and 21% were also positive using ISMAP02 and F57, respectively. None of the culture conditions supported the growth of M. avium subsp. paratuberculosis from PCR-positive samples. IS1311 REA and sequencing indicate that at least two different M. avium subsp. paratuberculosis strain types exist in Canadian wood bison. The presence of different M. avium subsp. paratuberculosis strains among wood bison herds should be considered in the planning of translocations. PMID:23686265

De Buck, Jeroen; Elkin, Brett; Kutz, Susan; van der Meer, Frank; Orsel, Karin

2013-01-01

335

Elevation of Mycobacterium tuberculosis subsp. caprae Aranaz et al. 1999 to species rank as Mycobacterium caprae comb. nov., sp. nov  

Microsoft Academic Search

Mycobacterium tuberculosis complex isolates recovered from goats were originally classified as Mycobacterium tuberculosis subsp. caprae; however, this subspecies was recently reclassified as Mycobacterium bovis subsp. caprae. Besides biochemical (sensitivity to pyrazinamide) and epidemiological features, strains of this unusual member of the M. tuberculosis complex show a special combination of pncA, oxyR, katG and gyrA gene polymorphisms. Sequence analysis of the

A. Aranaz; Debby Cousins; Ana Mateos; Lucas Dominguez

2003-01-01

336

Localization of proteins in the cell wall of Mycobacterium avium subsp. paratuberculosis K10 by proteomic analysis  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis is a pathogen which causes a debilitating chronic enteritis in ruminants. Unfortunately, the mechanisms that control M. avium subsp. paratuberculosis persistence during infection are poorly understood and the key steps for developing Johne's disease remain elusive. A proteomic analysis approach, based on one dimensional polyacrylamide gel electrophoresis (SDS-PAGE) followed by LC-MS\\/MS, was used to identify and

Zhiguo He; Jeroen De Buck

2010-01-01

337

UV Light Inactivation of Mycobacterium avium subsp. paratuberculosis in Milk as Assessed by FASTPlaqueTB Phage Assay and Culture  

Microsoft Academic Search

UV light inactivation of Mycobacterium avium subsp. paratuberculosis in Middlebrook 7H9 broth and whole and semiskim milk was investigated using a laboratory-scale UV machine that incorporated static mixers within UV-penetrable pipes. UV treatment proved to be less effective in killing M. avium subsp. paratuberculosis suspended in milk (0.5- to 1.0-log10 reduction per 1,000 mJ\\/ml) than that suspended in Middlebrook 7H9

Leslie C. Altic; Michael T. Rowe; Irene R. Grant

2007-01-01

338

Virulence and Immunity Orchestrated by the Global Gene Regulator sigL in Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Mycobacterium avium subsp. paratuberculosis causes Johne's disease in ruminants, a chronic enteric disease responsible for severe economic losses in the dairy industry. Global gene regulators, including sigma factors are important in regulating mycobacterial virulence. However, the biological significance of such regulators in M. avium subsp. paratuberculosis rremains elusive. To better decipher the role of sigma factors in M. avium subsp. paratuberculosis pathogenesis, we targeted a key sigma factor gene, sigL, activated in mycobacterium-infected macrophages. We interrogated an M. avium subsp. paratuberculosis ?sigL mutant against a selected list of stressors that mimic the host microenvironments. Our data showed that sigL was important in maintaining bacterial survival under such stress conditions. Survival levels further reflected the inability of the ?sigL mutant to persist inside the macrophage microenvironments. Additionally, mouse infection studies suggested a substantial role for sigL in M. avium subsp. paratuberculosis virulence, as indicated by the significant attenuation of the ?sigL-deficient mutant compared to the parental strain. More importantly, when the sigL mutant was tested for its vaccine potential, protective immunity was generated in a vaccine/challenge model of murine paratuberculosis. Overall, our study highlights critical role of sigL in the pathogenesis and immunity of M. avium subsp. paratuberculosis infection, a potential role that could be shared by similar proteins in other intracellular pathogens. PMID:24799632

Ghosh, Pallab; Steinberg, Howard

2014-01-01

339

Early responses to acute ozone exposure in two Fagus sylvatica clones differing in xeromorphic adaptations: photosynthetic and stomatal processes, membrane and epicuticular characteristics.  

PubMed

Two Fagus sylvatica L. clones were used to investigate the early responses to acute O3 exposure (150 nL L(-1), i.e., 1.35x ambient hourly peak in rural Italy) and whether xeromorphic adaptations affect gas exchange, membrane, and epicuticular responses. One clone originated in a wet and temperate climate in Central Italy (Tuscany); the other clone originated in a warmer and drier climate in the southern-most part of the F. sylvatica distribution (Sicily). Because of higher base gas exchange rates, the most negative effects of O3 exposure (gas exchange impairment, uncoupling between net photosynthesis and stomatal conductance, increased membrane lipid peroxidation) were found in the southern clone. Xeromorphic adaptations (higher epicuticular waxes and stomatal density, lower leaf wettability and size) were found in this clone. Our results suggest that xeromorphism may increase O3 sensitivity in species not adapted to face water stress, like the mesophilic F. sylvatica, when experiments are carried out with full irrigation. We present evidence describing the relationship between gas exchange and number and status of stomata. Stomatal density and the structural damage to stomata resulting from O3 exposure did not affect gas exchange: In fact, non-stomatal limitations to photosynthesis prevailed over stomatal limitations. PMID:17180427

Paoletti, Elena; Nali, Cristina; Lorenzini, Giacomo

2007-05-01

340

Canopy-level stomatal narrowing in adult Fagus sylvatica under O3 stress - means of preventing enhanced O3 uptake under high O3 exposure?  

PubMed

Spatio-temporally consistent O(3) doses are demonstrated in adult Fagus sylvatica from the Kranzberg Forest free-air fumigation experiment, covering cross-canopy and whole-seasonal scopes through sap flow measurement. Given O(3)-driven closure of stomata, we hypothesized enhanced whole-tree level O(3) influx to be prevented under enhanced O(3) exposure. Although foliage transpiration rate was lowered under twice-ambient O(3) around noon by 30% along with canopy conductance, the hypothesis was falsified, as O(3) influx was raised by 25%. Nevertheless, the twice-ambient/ambient ratio of O(3) uptake was smaller by about 20% than that of O(3) exposure, suggesting stomatal limitation of uptake. The O(3) response was traceable from leaves across branches to the canopy, where peak transpiration rates resembled those of shade rather than sun branches. Rainy/overcast-day and nightly O(3) uptake is quantified and discussed. Whole-seasonal canopy-level validation of modelled with sap flow-derived O(3) flux becomes available in assessing O(3) risk for forest trees. PMID:25062776

Matyssek, R; Baumgarten, M; Hummel, U; Häberle, K-H; Kitao, M; Wieser, G

2015-01-01

341

Impact of elevated atmospheric O3 on the actinobacterial community structure and function in the rhizosphere of European beech (Fagus sylvatica L.)  

PubMed Central

Many bacteria belonging to the phylum of Actinobacteria are known as antagonists against phytpathogenic microbes. This study aimed to analyze the effect of ozone on the actinobacterial community of the rhizosphere of four years old European beech (Fagus sylvatica L.) trees during different time points of the vegetation period. Effects of ozone on the total community structure of Actinobacteria were studied based on the analysis of 16S rRNA gene amplicons. In addition effects of the ozone treatment on the diversity of potential biocontrol active Actionobacteria being able to produce antibiotics were characterized by using the type II polyketide synthases (PKS) genes as marker. Season as well as ozone treatments had a significant effect on parts of the actinobacterial rhizosphere community of European beech. However on the basis of the performed analysis, the diversity of Actinobacteria possessing type II PKS genes is neither affected by seasonal changes nor by the ozone treatments, indicating no influence of the investigated treatments on the biocontrol active part of the actinobacterial community. PMID:24575080

Haesler, Felix; Hagn, Alexandra; Engel, Marion; Schloter, Michael

2014-01-01

342

Wide variation in spatial genetic structure between natural populations of the European beech (Fagus sylvatica) and its implications for SGS comparability  

PubMed Central

Identification and quantification of spatial genetic structure (SGS) within populations remains a central element of understanding population structure at the local scale. Understanding such structure can inform on aspects of the species' biology, such as establishment patterns and gene dispersal distance, in addition to sampling design for genetic resource management and conservation. However, recent work has identified that variation in factors such as sampling methodology, population characteristics and marker system can all lead to significant variation in SGS estimates. Consequently, the extent to which estimates of SGS can be relied on to inform on the biology of a species or differentiate between experimental treatments is open to doubt. Following on from a recent report of unusually extensive SGS when assessed using amplified fragment length polymorphisms in the tree Fagus sylvatica, we explored whether this marker system led to similarly high estimates of SGS extent in other apparently similar populations of this species. In the three populations assessed, SGS extent was even stronger than this previously reported maximum, extending up to 360?m, an increase in up to 800% in comparison with the generally accepted maximum of 30–40?m based on the literature. Within this species, wide variation in SGS estimates exists, whether quantified as SGS intensity, extent or the Sp parameter. Consequently, we argue that greater standardization should be applied in sample design and SGS estimation and highlight five steps that can be taken to maximize the comparability between SGS estimates. PMID:22354112

Jump, A S; Rico, L; Coll, M; Peñuelas, J

2012-01-01

343

Variation in photosynthetic performance and hydraulic architecture across European beech (Fagus sylvatica L.) populations supports the case for local adaptation to water stress.  

PubMed

The aim of this study was to provide new insights into how intraspecific variability in the response of key functional traits to drought dictates the interplay between gas-exchange parameters and the hydraulic architecture of European beech (Fagus sylvatica L.). Considering the relationships between hydraulic and leaf functional traits, we tested whether local adaptation to water stress occurs in this species. To address these objectives, we conducted a glasshouse experiment in which 2-year-old saplings from six beech populations were subjected to different watering treatments. These populations encompassed central and marginal areas of the range, with variation in macro- and microclimatic water availability. The results highlight subtle but significant differences among populations in their functional response to drought. Interpopulation differences in hydraulic traits suggest that vulnerability to cavitation is higher in populations with higher sensitivity to drought. However, there was no clear relationship between variables related to hydraulic efficiency, such as xylem-specific hydraulic conductivity or stomatal conductance, and those that reflect resistance to xylem cavitation (i.e., ?(12), the water potential corresponding to a 12% loss of stem hydraulic conductivity). The results suggest that while a trade-off between photosynthetic capacity at the leaf level and hydraulic function of xylem could be established across populations, it functions independently of the compromise between safety and efficiency of the hydraulic system with regard to water use at the interpopulation level. PMID:25536961

Aranda, Ismael; Cano, Francisco Javier; Gascó, Antonio; Cochard, Hervé; Nardini, Andrea; Mancha, Jose Antonio; López, Rosana; Sánchez-Gómez, David

2015-01-01

344

Detecting short spatial scale local adaptation and epistatic selection in climate-related candidate genes in European beech (Fagus sylvatica) populations.  

PubMed

Detecting signatures of selection in tree populations threatened by climate change is currently a major research priority. Here, we investigated the signature of local adaptation over a short spatial scale using 96 European beech (Fagus sylvatica L.) individuals originating from two pairs of populations on the northern and southern slopes of Mont Ventoux (south-eastern France). We performed both single and multilocus analysis of selection based on 53 climate-related candidate genes containing 546 SNPs. FST outlier methods at the SNP level revealed a weak signal of selection, with three marginally significant outliers in the northern populations. At the gene level, considering haplotypes as alleles, two additional marginally significant outliers were detected, one on each slope. To account for the uncertainty of haplotype inference, we averaged the Bayes factors over many possible phase reconstructions. Epistatic selection offers a realistic multilocus model of selection in natural populations. Here, we used a test suggested by Ohta based on the decomposition of the variance of linkage disequilibrium. Overall populations, 0.23% of the SNP pairs (haplotypes) showed evidence of epistatic selection, with nearly 80% of them being within genes. One of the between gene epistatic selection signals arose between an FST outlier and a nonsynonymous mutation in a drought response gene. Additionally, we identified haplotypes containing selectively advantageous allele combinations which were unique to high or low elevations and northern or southern populations. Several haplotypes contained nonsynonymous mutations situated in genes with known functional importance for adaptation to climatic factors. PMID:25156570

Csilléry, Katalin; Lalagüe, Hadrien; Vendramin, Giovanni G; González-Martínez, Santiago C; Fady, Bruno; Oddou-Muratorio, Sylvie

2014-10-01

345

Assessment of spatial discordance of primary and effective seed dispersal of European beech (Fagus sylvatica L.) by ecological and genetic methods.  

PubMed

Spatial discordance between primary and effective dispersal in plant populations indicates that postdispersal processes erase the seed rain signal in recruitment patterns. Five different models were used to test the spatial concordance of the primary and effective dispersal patterns in a European beech (Fagus sylvatica) population from central Spain. An ecological method was based on classical inverse modelling (SSS), using the number of seed/seedlings as input data. Genetic models were based on direct kernel fitting of mother-to-offspring distances estimated by a parentage analysis or were spatially explicit models based on the genotype frequencies of offspring (competing sources model and Moran-Clark's Model). A fully integrated mixed model was based on inverse modelling, but used the number of genotypes as input data (gene shadow model). The potential sources of error and limitations of each seed dispersal estimation method are discussed. The mean dispersal distances for seeds and saplings estimated with these five methods were higher than those obtained by previous estimations for European beech forests. All the methods show strong discordance between primary and effective dispersal kernel parameters, and for dispersal directionality. While seed rain was released mostly under the canopy, saplings were established far from mother trees. This discordant pattern may be the result of the action of secondary dispersal by animals or density-dependent effects; that is, the Janzen-Connell effect. PMID:23379310

Millerón, M; López de Heredia, U; Lorenzo, Z; Alonso, J; Dounavi, A; Gil, L; Nanos, N

2013-03-01

346

Efficacy of Various Pasteurization Time-Temperature Conditions in Combination with Homogenization on Inactivation of Mycobacterium avium subsp. paratuberculosis in Milk  

Microsoft Academic Search

The effect of various pasteurization time-temperature conditions with and without homogenization on the viability of Mycobacterium avium subsp. paratuberculosis was investigated using a pilot-scale commercial high-temperature, short-time (HTST) pasteurizer and raw milk spiked with 101 to 105 M. avium subsp. paratuberculosis cells\\/ml. Viable M. avium subsp. paratuberculosis was cultured from 27 (3.3%) of 816 pasteur- ized milk samples overall, 5

Irene R. Grant; Alan G. Williams; Michael T. Rowe; D. Donald Muir

2005-01-01

347

Evaluation and histological examination of a Campylobacter fetus subsp. venerealis small animal infection model.  

PubMed

Bovine genital campylobacteriosis (BGC), caused by Campylobacter fetus subsp. venerealis, is associated with production losses in cattle worldwide. This study aimed to develop a reliable BGC guinea pig model to facilitate future studies of pathogenicity, abortion mechanisms and vaccine efficacy. Seven groups of five pregnant guinea pigs (1 control per group) were inoculated with one of three strains via intra-peritoneal (IP) or intra-vaginal routes. Samples were examined using culture, PCR and histology. Abortions ranged from 0% to 100% and re-isolation of causative bacteria from sampled sites varied with strain, dose of bacteria and time to abortion. Histology indicated metritis and placentitis, suggesting that the bacteria induce inflammation, placental detachment and subsequent abortion. Variation of virulence between strains was observed and determined by culture and abortion rates. IP administration of C. fetus subsp. venerealis to pregnant guinea pigs is a promising small animal model for the investigation of BGC abortion. PMID:25599935

Koya, A; de Wet, S C; Turner, S; Cawdell-Smith, J; Venus, B; Greer, R M; Lew-Tabor, A E; Boe-Hansen, G B

2015-04-01

348

Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: Characterization of the bacteriocin  

PubMed Central

Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality. PMID:25763065

Furtado, Danielle N.; Todorov, Svetoslav D.; Landgraf, Mariza; Destro, Maria T.; Franco, Bernadette D.G.M.

2014-01-01

349

Disseminated Mycobacterium avium subsp. paratuberculosis infection in two wild Eurasian otters (Lutra lutra L.) from Portugal.  

PubMed

Disseminated Mycobacterium avium subsp. paratuberculosis (MAP) infections were found in two Eurasian otters (Lutra lutra, L. 1758) killed by vehicular trauma in February and March 2010 in Castelo Branco, Portugal. At postmortem examination, the organs showed no significant gross alterations; however, microscopically, both animals had diffuse lymphadenitis with macrophage infiltration and deposition of hyaline material in the center of the lymphoid follicles. Acid-fast organisms were isolated from gastrointestinal tissue samples via bacteriologic culture. These organisms were identified as M. avium subsp. paratuberculosis by IS900 polymerase chain reaction (PCR). Additionally, direct IS900 PCR-positive results were obtained for multiple organs of both animals. This is the first report of MAP infection of otters in Portugal. PMID:23505727

Matos, Ana Cristina; Figueira, Luis; Martins, Maria Helena; Matos, Manuela; Alvares, Sofia; Pinto, Maria Lurdes; Coelho, Ana Cláudia

2013-03-01

350

Larvicidal activity of Bacillus thuringiensis subsp. israelensis in the dipteran Haematobia irritans.  

PubMed Central

A strain of Bacillus thuringiensis subsp. israelensis was found to be larvicidal to horn flies, Haematobia irritans (L. [Diptera:Muscidae]). The toxic activity was particulate, appeared during sporulation, and could be prevented by the addition of streptomycin before sporulation. Density gradient centrifugation in Renografin was used to separate endospores, crystals, and low-density particulate matter (fraction 3) from sporulated preparations. Larvicidal activity was restricted to purified crystals and fraction 3, indicating that delta-endotoxin of B. thuringiensis subsp. israelensis was active against horn fly larvae. Purified crystals produced mortality during larval feeding stages, but not pupal stages. Fraction 3 produced significant mortality during both larval and pupal stages. The mortality data indicated the presence of at least two dipteran-active toxins. PMID:6742837

Temeyer, K B

1984-01-01

351

Antibacterial activities of naturally occurring compounds against Mycobacterium avium subsp. paratuberculosis.  

PubMed

The antibacterial activities of 18 naturally occurring compounds (including essential oils and some of their isolated constituents, apple and green tea polyphenols, and other plant extracts) against three strains of Mycobacterium avium subsp. paratuberculosis (a bovine isolate [NCTC 8578], a raw-milk isolate [806R], and a human isolate [ATCC 43015]) were evaluated using a macrobroth susceptibility testing method. M. avium subsp. paratuberculosis was grown in 4 ml Middlebrook 7H9 broth containing 10% oleic acid-albumin-dextrose-catalase, 0.05% Tween 80 (or 0.2% glycerol), and 2 microg/ml mycobactin J supplemented with five concentrations of each test compound. The changes in the optical densities of the cultures at 600 nm as a measure of CFU were recorded at intervals over an incubation period of 42 days at 37 degrees C. Six of the compounds were found to inhibit the growth of M. avium subsp. paratuberculosis. The most effective compound was trans-cinnamaldehyde, with a MIC of 25.9 microg/ml, followed by cinnamon oil (26.2 microg/ml), oregano oil (68.2 microg/ml), carvacrol (72.2 microg/ml), 2,5-dihydroxybenzaldehyde (74 microg/ml), and 2-hydroxy-5-methoxybenzaldehyde (90.4 microg/ml). With the exception of carvacrol, a phenolic compound, three of the four most active compounds are aldehydes, suggesting that the structure of the phenolic group or the aldehyde group may be important to the antibacterial activity. No difference in compound activity was observed between the three M. avium subsp. paratuberculosis strains studied. Possible mechanisms of the antimicrobial effects are discussed. PMID:18676709

Wong, Stella Y Y; Grant, Irene R; Friedman, Mendel; Elliott, Christopher T; Situ, Chen

2008-10-01

352

Avian wildlife reservoir of Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. in Norway.  

PubMed Central

Cloacal swabs from 540 wild-living birds were cultured for Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. The carrier rates detected were as follows: C. fetus subsp. jejuni, 28.4%; Yersinia spp., 1.2%; and Salmonella spp., 0.8%. All birds were apparently healthy when captured. C. fetus subsp. jejuni was isolated from 11 of the 40 bird species examined. Among birds inhabiting the city of Oslo, the highest isolation rate was found in crows (Corvus corone cornix) (89.8%), followed by gulls (Larus spp.) (50.0%) and domestic pigeons (Columba livia domesticus) (4.2%). The gulls and crows scavenge on refuse dumps. High carrier rates were also detected among the following birds from nonurban, coastal areas: puffin (Fratercula arctica) (51.3%), common tern (Sterna hirundo) (5.6%), common gull (Larus canus) (18.9%), black-headed gull (Larus ridibundus) (13.2%), and herring gull (Larus argentatus) (4.2%). The list of species harboring C. fetus subsp. jejuni also includes the Ural owl (Strix uralensis), goldeneye (Bucephala clangula), and reed bunting (Emberiza schoeniclus). The following five Yersinia strains were isolated: Y. kristensenii (two strains), Y. intermedia (two strains), and "Yersinia X2" (one strain). Four strains belonging to the genus Salmonella were isolated from three different species of gulls. These isolates were identified as S. typhimurium, S. indiana, and S. djugu. The results indicate that campylobacters are a normal component of the intestinal flora in several bird species, whereas Salmonella and Yersinia carriers are more sporadic. PMID:6338824

Kapperud, G; Rosef, O

1983-01-01

353

Regional persistence of an endemic plant, Erigeron acer subsp. decoloratus , in disturbed riparian habitats  

Microsoft Academic Search

Regional persistence of species requires a positive balance between colonizations and local extinctions. In this study, we\\u000a examined the amount of colonizations and extinctions and their likelihood as a function of patch size, isolation, and habitat\\u000a characteristics of a riparian perennial plant, Erigeron acer subsp. decoloratus. We also studied the importance of patch dynamics to the regional population growth. Over

Anne Jäkäläniemi; Pirkko Siikamäki; Anna Kilpiä; Juha Tuomi

2009-01-01

354

Characterization of the Highly Autolytic Lactococcus lactis subsp. cremoris Strains CO and 2250  

PubMed Central

Two highly autolytic Lactococcus lactis subsp. cremoris strains (CO and 2250) were selected and analyzed for their autolytic properties. Both strains showed maximum lysis when grown in M17 broth containing a limiting concentration of glucose (0.4 to 0.5%) as the carbohydrate source. Lysis did not vary greatly with pH or temperature but was reduced when strains were grown on lactose or galactose. Growth in M17 containing excess glucose (1%) prevented autolysis, although rapid lysis of L. lactis subsp. cremoris CO did occur in the presence of 1% glucose if sodium fluoride (an inhibitor of glycolysis) was added to the medium. Maximum cell lysis in a buffer system was observed early in the stationary phase, and for CO, two pH optima were observed for log-phase and stationary-phase cells (6.5 and 8.5, respectively). Autolysins were extracted from the cell wall fraction of each strain by using either 4% sodium dodecyl sulfate (SDS), 6 M guanidine hydrochloride, or 4 M lithium chloride, and their activities were analyzed by renaturing SDS-polyacrylamide gel electrophoresis on gels containing Micrococcus luteus or L. lactis subsp. cremoris CO cells as the substrate. More than one lytic band was observed on each substrate, with the major band having an apparent molecular mass of 48 kDa for CO. Each lytic band was present throughout growth and lysis. These results suggest that at least two different autolytic enzymes are present in the autolytic L. lactis subsp. cremoris strains. The presence of the lactococcal cell wall hydrolase gene, acmA (G. Buist, J. Kok, K. J. Leenhouts, M. Dabrowska, G. Venema, and A. J. Haandrikman, J. Bacteriol. 177:1554-1563, 1995), in strains 2250 and CO was confirmed by Southern hybridization. Analysis of an acmA deletion mutant of 2250 confirmed that the gene was involved in cell separation and had a role in cell lysis. PMID:16535702

Riepe, H. R.; Pillidge, C. J.; Gopal, P. K.; Mckay, L. L.

1997-01-01

355

An ultrastructural study of the mature spermatozoid of the fern Asplenium trichomanes L. subsp. trichomanes  

Microsoft Academic Search

Asplenium trichomanes L. subsp. trichomanes spermatozoids are spirals of about five turns. Keels link the elements of the microtubular ribbon with the plates of the lamellar\\u000a layer (LL) which are uninterrupted, parallel and curved with an inner angle of about 150. Electron-opaque filaments connect\\u000a the microtubules of the multilayered structure (MLS) and the osmiophilic crest, the LL and the MLS-associated

P. Gori; Simonetta Muccifora; Sheridan L. Woo; Lorenza M. Bellani

1997-01-01

356

Antimicrobial activity and chemical composition of endemic Centaurea cariensis subsp. niveo-tomentosa  

Microsoft Academic Search

The antimicrobial activity of the n-hexane, chloroform, ethyl acetate and ethyl alcohol extracts of the aerial parts of Centaurea cariensis subsp. niveo-tomentosa was evaluated against microorganisms, including multi-antibiotic resistant bacteria, using the paper disc diffusion method. The chemical composition of the chloroform extract of this plant was determined by gas chromatography and gas chromatography-mass spectrometry. The chloroform extract exhibited significant

Aysel Ugur; Nurdan Sarac; Ozgur Ceylan; M. Emin Duru

2010-01-01

357

Cytological mechanisms of 2n egg formation in a diploid genotype of Medicago sativa subsp. falcata  

Microsoft Academic Search

Gametes formed without meiosis in alfalfa would be useful in basic and applied research. Therefore, the cytological analysis of macrosporogenesis of a diploid plant of Medicago sativa subsp. falcata (L.) Arcangeli (named PG-F9), previously selected as a good 2n egg producer, was conducted. A stain-clearing technique was applied which also allowed the analysis of microsporogenesis to be performed. Two mechanisms

S. Tavoletti

1994-01-01

358

Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing toxin genes from Bacillus thuringiensis subsp. israelensis  

Microsoft Academic Search

Genes encoding the mosquito larvicidal toxins Cry4Aa, Cry11Aa, Cyt1Aa and the regulatory P20 from Bacillus thuringiensis subsp. israelensis were introduced into the nitrogen-fixing, filamentous cyanobacterium Anabaena PCC 7120 for expression under control of two strong promoters PpsbA and PA1. The clone pRVE4-ADRC displayed toxicity against fourth-instar larvae of Aedes aegypti, the highest ever achieved in cyanobacteria. It was about 2.5-fold

Vadim Khasdan; Eitan Ben-Dov; Robert Manasherob; Sammy Boussiba; Arieh Zaritsky

2003-01-01

359

Hydraulic redistribution in Eucalyptus kochii subsp. borealis with variable access to fresh groundwater  

Microsoft Academic Search

Salinity caused by land clearing is an important cause of land degradation in the Western Australian wheatbelt. Returning\\u000a a proportion of the cleared land to higher water use perennial vegetation is one option for reducing or slowing the salinisation\\u000a of land. Over the course of a year patterns of water use by Eucalyptus kochii subsp borealis (C. Gardner) D. Nicolle,

K. Brooksbank; D. A. White; E. J. Veneklaas; J. L. Carter

2011-01-01

360

Novel Phytases from Bifidobacterium pseudocatenulatum ATCC 27919 and Bifidobacterium longum subsp. infantis ATCC 15697  

PubMed Central

Two novel phytases have been characterized from Bifidobacterium pseudocatenulatum and Bifidobacterium longum subsp. infantis. The enzymes belong to a new subclass within the histidine acid phytases, are highly specific for the hydrolysis of phytate, and render myo-inositol triphosphate as the final hydrolysis product. They represent the first phytases characterized from this group of probiotic microorganisms, opening the possibilities for their use in the processing of high-phytate-content foods. PMID:22582052

Tamayo-Ramos, Juan Antonio; Sanz-Penella, Juan Mario; Yebra, María J.

2012-01-01

361

Bilateral polyploidization in Dactylis glomerata L. subsp. lusitanica : occurrence, morphological and genetic characteristics of first polyploids  

Microsoft Academic Search

Summary InDactylis glomerata L. subsp.lusitanica, triploid and tetraploid plants were obtained by bilateral sexual polyploidization in crosses between diploid parents known to produce 2n gametes. The polyploid and diploid progeny were compared for allozyme diversity (allele number and heterozygosity), phenological (pollen fertility, inflorescence emergence date), cellular (stomatic cell size) and morphological characters (vegetative biomass, seed weight, total seed number per

F. Bretagnolle; R. Lumaret

1995-01-01

362

Complete genome sequence of a plant associated bacterium Bacillus amyloliquefaciens subsp. plantarum UCMB5033  

PubMed Central

Bacillus amyloliquefaciens subsp. plantarum UCMB5033 is of special interest for its ability to promote host plant growth through production of stimulating compounds and suppression of soil borne pathogens by synthesizing antibacterial and antifungal metabolites or priming plant defense as induced systemic resistance. The genome of B. amyloliquefaciens UCMB5033 comprises a 4,071,167 bp long circular chromosome that consists of 3,912 protein-coding genes, 86 tRNA genes and 10 rRNA operons. PMID:25197456

Niazi, Adnan; Manzoor, Shahid; Bejai, Sarosh; Meijer, Johan; Bongcam-Rudloff, Erik

2014-01-01

363

Antibacterial Activities of Naturally Occurring Compounds against Mycobacterium avium subsp. paratuberculosis?  

PubMed Central

The antibacterial activities of 18 naturally occurring compounds (including essential oils and some of their isolated constituents, apple and green tea polyphenols, and other plant extracts) against three strains of Mycobacterium avium subsp. paratuberculosis (a bovine isolate [NCTC 8578], a raw-milk isolate [806R], and a human isolate [ATCC 43015]) were evaluated using a macrobroth susceptibility testing method. M. avium subsp. paratuberculosis was grown in 4 ml Middlebrook 7H9 broth containing 10% oleic acid-albumin-dextrose-catalase, 0.05% Tween 80 (or 0.2% glycerol), and 2 ?g/ml mycobactin J supplemented with five concentrations of each test compound. The changes in the optical densities of the cultures at 600 nm as a measure of CFU were recorded at intervals over an incubation period of 42 days at 37°C. Six of the compounds were found to inhibit the growth of M. avium subsp. paratuberculosis. The most effective compound was trans-cinnamaldehyde, with a MIC of 25.9 ?g/ml, followed by cinnamon oil (26.2 ?g/ml), oregano oil (68.2 ?g/ml), carvacrol (72.2 ?g/ml), 2,5-dihydroxybenzaldehyde (74 ?g/ml), and 2-hydroxy-5-methoxybenzaldehyde (90.4 ?g/ml). With the exception of carvacrol, a phenolic compound, three of the four most active compounds are aldehydes, suggesting that the structure of the phenolic group or the aldehyde group may be important to the antibacterial activity. No difference in compound activity was observed between the three M. avium subsp. paratuberculosis strains studied. Possible mechanisms of the antimicrobial effects are discussed. PMID:18676709

Wong, Stella Y. Y.; Grant, Irene R.; Friedman, Mendel; Elliott, Christopher T.; Situ, Chen

2008-01-01

364

Experimental Paratuberculosis in Calves following Inoculation with a Rabbit Isolate of Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

The role of wildlife species in the epidemiology of paratuberculosis has been the subject of increased research efforts following the discovery of natural paratuberculosis in free-living rabbits from farms in east Scotland. This paper describes the experimental inoculation of young calves with an isolate of Mycobacterium avium subsp. paratuberculosis recovered from a free-living rabbit. After a 6-month incubation period, all

P. M. Beard; K. Stevenson; A. Pirie; K. Rudge; D. Buxton; S. M. Rhind; M. C. Sinclair; L. A. Wildblood; D. G. Jones; J. M. Sharp

2001-01-01

365

Roles of the Surface Layer Proteins of Campylobacter fetus subsp. fetus in Ovine Abortion  

Microsoft Academic Search

The role of the surface (S)-layer proteins of Campylobacter fetus subsp. fetus has been investigated using an ovine model of abortion. Wild-type strain 23D induced abortion in up to 90% of pregnant ewes challenged subcutaneously. Isolates recovered from both dams and fetuses expressed S-layer proteins with variable molecular masses. The spontaneous S-layer-negative variant, strain 23B, neither colonized nor caused abor-

R. Grogono-Thomas; J. Dworkin; M. J. Blaser; D. G. Newell

2000-01-01

366

Draft Genome Sequence of Xylella fastidiosa subsp. multiplex Strain Griffin-1 from Quercus rubra in Georgia  

PubMed Central

The draft genome sequence of Xylella fastidiosa subsp. multiplex strain Griffin-1, isolated from a red oak tree (Quercus rubra) in Georgia, is reported here. The bacterium has a genome size of 2,387,314 bp, with a G+C content of 51.7%. The Griffin-1 strain genome contains 2,903 predicted open reading frames and 50 RNA genes. PMID:24115539

Huang, Hong; Chang, Chung-Jan; Stenger, Drake C.

2013-01-01

367

Avian wildlife reservoir of Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. in Norway.  

PubMed

Cloacal swabs from 540 wild-living birds were cultured for Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. The carrier rates detected were as follows: C. fetus subsp. jejuni, 28.4%; Yersinia spp., 1.2%; and Salmonella spp., 0.8%. All birds were apparently healthy when captured. C. fetus subsp. jejuni was isolated from 11 of the 40 bird species examined. Among birds inhabiting the city of Oslo, the highest isolation rate was found in crows (Corvus corone cornix) (89.8%), followed by gulls (Larus spp.) (50.0%) and domestic pigeons (Columba livia domesticus) (4.2%). The gulls and crows scavenge on refuse dumps. High carrier rates were also detected among the following birds from nonurban, coastal areas: puffin (Fratercula arctica) (51.3%), common tern (Sterna hirundo) (5.6%), common gull (Larus canus) (18.9%), black-headed gull (Larus ridibundus) (13.2%), and herring gull (Larus argentatus) (4.2%). The list of species harboring C. fetus subsp. jejuni also includes the Ural owl (Strix uralensis), goldeneye (Bucephala clangula), and reed bunting (Emberiza schoeniclus). The following five Yersinia strains were isolated: Y. kristensenii (two strains), Y. intermedia (two strains), and "Yersinia X2" (one strain). Four strains belonging to the genus Salmonella were isolated from three different species of gulls. These isolates were identified as S. typhimurium, S. indiana, and S. djugu. The results indicate that campylobacters are a normal component of the intestinal flora in several bird species, whereas Salmonella and Yersinia carriers are more sporadic. PMID:6338824

Kapperud, G; Rosef, O

1983-02-01

368

Antioxidant and antiproliferative activity of Hypericum hircinum L. subsp. majus (Aiton) N. Robson essential oil  

Microsoft Academic Search

This study was undertaken to assess the antioxidant and antiproliferative potential of the essential oil of Hypericum hircinum L. subsp. majus (Aiton) N. Robson. Analysis of the oil composition revealed that sesquiterpene hydrocarbons (69.3%) dominate, cis-?-guaiene, ?-selinene and (E)-caryophyllene being the most representative. Significant values of antioxidant activity were found using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2?-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays.

Luana Quassinti; Giulio Lupidi; Filippo Maggi; Gianni Sagratini; Fabrizio Papa; Sauro Vittori; Armandodoriano Bianco; Massimo Bramucci

2012-01-01

369

Effective heat inactivation of Mycobacterium avium subsp. paratuberculosis in raw milk contaminated with naturally infected feces.  

PubMed

The effectiveness of high-temperature, short holding time (HTST) pasteurization and homogenization with respect to inactivation of Mycobacterium avium subsp. paratuberculosis was evaluated quantitatively. This allowed a detailed determination of inactivation kinetics. High concentrations of feces from cows with clinical symptoms of Johne's disease were used to contaminate raw milk in order to realistically mimic possible incidents most closely. Final M. avium subsp. paratuberculosis concentrations varying from 10(2) to 3.5 x 10(5) cells per ml raw milk were used. Heat treatments including industrial HTST were simulated on a pilot scale with 22 different time-temperature combinations, including 60 to 90 degrees C at holding (mean residence) times of 6 to 15 s. Following 72 degrees C and a holding time of 6 s, 70 degrees C for 10 and 15 s, or under more stringent conditions, no viable M. avium subsp. paratuberculosis cells were recovered, resulting in >4.2- to >7.1-fold reductions, depending on the original inoculum concentrations. Inactivation kinetic modeling of 69 quantitative data points yielded an E(a) of 305,635 J/mol and an lnk(0) of 107.2, corresponding to a D value of 1.2 s at 72 degrees C and a Z value of 7.7 degrees C. Homogenization did not significantly affect the inactivation. The conclusion can be drawn that HTST pasteurization conditions equal to 15 s at > or =72 degrees C result in a more-than-sevenfold reduction of M. avium subsp. paratuberculosis. PMID:17496131

Rademaker, Jan L W; Vissers, Marc M M; Te Giffel, Meike C

2007-07-01

370

Complete Genome Sequence of Type Strain Pasteurella multocida subsp. multocida ATCC 43137  

PubMed Central

Soft-tissue infection by Pasteurella multocida in humans is usually associated with a dog- or cat-related injury, and these infections can become aggressive. We sequenced the type strain P. multocida subsp. multocida ATCC 43137 into a single closed chromosome consisting of 2,271,840 bp (40.4% G+C content), which is currently available in the NCBI GenBank under the accession number CP008918. PMID:25342682

Davenport, K. W.; Daligault, H. E.; Minogue, T. D.; Bishop-Lilly, K. A.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Frey, K. G.; Jaissle, J.; Koroleva, G. I.; Ladner, J. T.; Lo, C. C.; Palacios, G. F.; Redden, C. L.; Scholz, M. B.; Teshima, H.

2014-01-01

371

Draft Genome Sequence of Xylella fastidiosa subsp. multiplex Strain Griffin-1 from Quercus rubra in Georgia.  

PubMed

The draft genome sequence of Xylella fastidiosa subsp. multiplex strain Griffin-1, isolated from a red oak tree (Quercus rubra) in Georgia, is reported here. The bacterium has a genome size of 2,387,314 bp, with a G+C content of 51.7%. The Griffin-1 strain genome contains 2,903 predicted open reading frames and 50 RNA genes. PMID:24115539

Chen, Jianchi; Huang, Hong; Chang, Chung-Jan; Stenger, Drake C

2013-01-01

372

Growth and Energy Generation by Lactococcus lactis subsp. lactis biovar diacetylactis during Citrate Metabolism  

PubMed Central

Growth of Lactococcus lactis subsp. lactis biovar diacetylactis was observed on media with citrate as the only energy source. At pH 5.6, steady state was achieved in a chemostat on a citrate-containing medium in the absence of a carbohydrate. Under these conditions, pyruvate, acetate, and some acetoin and butanediol were the main fermentation products. This indicated that energy was conserved in L. lactis subsp. lactis biovar diacetylactis during citrate metabolism and presumably during the conversion of citrate into pyruvate. The presumed energy-conserving step, decarboxylation of oxaloacetate, was studied in detail. Oxaloacetate decarboxylase was purified to homogeneity and characterized. The enzyme has a native molecular mass of approximately 300 kDa and consists of three subunits of 52, 34, and 12 kDa. The enzyme is apparently not sodium dependent and does not contain a biotin moiety, and it seems to be different from the energy-generating oxaloacetate decarboxylase from Klebsiella pneumoniae. Energy-depleted L. lactis subsp. lactis biovar diacetylactis cells generated a membrane potential and a pH gradient immediately upon addition of citrate, whereas ATP formation was slow and limited. In contrast, lactose energization resulted in rapid ATP formation and gradual generation of a proton motive force. These data were confirmed during studies on amino acid uptake. ?-Aminoisobutyrate uptake was rapid but glutamate uptake was slow in citrate-energized cells, whereas lactose-energized cells showed the reverse tendency. These data suggest that, in L. lactis subsp. lactis bv. diacetylactis, a proton motive force could be generated during citrate metabolism as a result of electrogenic citrate uptake or citrate/product exchange together with proton consumption by the intracellular oxaloacetate decarboxylase. Images PMID:16349120

Hugenholtz, Jeroen; Perdon, Leo; Abee, Tjakko

1993-01-01

373

Complete Genome Sequence of Lactococcus lactis subsp. lactis KLDS4.0325  

PubMed Central

We report the complete genome sequence of Lactococcus lactis subsp. lactis KLDS4.0325, a probiotic bacterium isolated from homemade koumiss in Xinjiang, China. We have determined the complete genome sequence of strain KLDS4.0325, which consists of a chromosome and three plasmids and reveals genes that are likely to be involved in dairy fermentation and that have probiotic qualities. PMID:24285665

Yang, Xiaochun; Wang, Yutang

2013-01-01

374

In vitro regeneration of Carlina acaulis subsp. simplex from seedling explants  

Microsoft Academic Search

The aim of the study was to obtain an efficient system for Carlina acaulis subsp. simplex propagation. The experimental materials were shoot tips, fragments of hipocotyls, cotyledons and roots isolated from 10-day-old\\u000a seedlings. The explants were transferred to the proliferation medium supplemented with different types of cytokinin: BA (13.3 ?M),\\u000a kinetin (13.9 ?M) and zeatin (13.7 ?M) in combination with NAA (0.54 ?M). The

Alina Trejgell; Gra?yna D?browska; Andrzej Tretyn

2009-01-01

375

Toxicity and synergism in transgenic Escherichia coli expressing four genes from Bacillus thuringiensis subsp. israelensis  

Microsoft Academic Search

Summary The genes cyt1Aa and p20, encoding, respectively, cytolytic and accessory proteins of Bacillus thurin- giensis subsp. israelensis, were introduced into previously constructed clones expressing cry4Aa and cry11Aa in Escherichia coli (Ben-Dov et al., 1995). Fifteen clones with all possible combinations of the four genes were obtained and found to express the genes included. Two new combinations, pVE4- ADRC and

Vadim Khasdan; Eitan Ben-Dov; Robert Manasherob; Sammy Boussiba; Arieh Zaritsky

2001-01-01

376

Endocarditis in chickens caused by subclinical infection of Streptococcus gallolyticus subsp. gallolyticus.  

PubMed

Streptococcus gallolyticus subsp. gallolyticus causes endocarditis in humans and acute septicemia in domestic birds. We describe here the infective endocarditis caused by the bacterium found among clinically healthy broilers at two abattoirs in Japan. The chickens were thought to be healthy because of the lack of clinical symptoms and normal levels of mortality before slaughtering. At the time of inspection, some chickens were condemned because of organ disorders characterized by vegetative valvular endocarditis as well as focal necrosis in heart, liver, and spleen. Streptococcus gallolyticus subsp. gallolyticus was isolated from the organs as a pure culture, indicating that the bacterium probably was the causative agent of the disorders. Amplified fragment length polymorphism analysis of the isolates collected at the abattoirs from chickens grown in nine different farms indicated that the isolates were different variants of the same clonal lineage and may have been derived from the same ancestor. These results suggest that S. gallolyticus subsp. gallolyticus causes infectious endocarditis in chickens and that healthy chickens may possess the bacterium in their normal flora as an opportunistic pathogen. PMID:18459321

Sekizaki, Tsutomu; Nishiya, Hideki; Nakajima, Seigo; Nishizono, Mikio; Kawano, Masanori; Okura, Masatoshi; Takamatsu, Daisuke; Nishino, Hiroto; Ishiji, Tomono; Osawa, Ro

2008-03-01

377

Multiplex PCR-Based Method for Identification of Common Clinical Serotypes of Salmonella enterica subsp. enterica?  

PubMed Central

A multiplex PCR method has been developed to differentiate between the most common clinical serotypes of Salmonella enterica subsp. enterica encountered in Washington State and the United States in general. Six genetic loci from S. enterica serovar Typhimurium and four from S. enterica serovar Typhi were used to create an assay consisting of two five-plex PCRs. The assays gave reproducible results with 30 different serotypes that represent the most common clinical isolates of S. enterica subsp. enterica. Of these, 22 serotypes gave unique amplification patterns compared with each other and the other 8 serotypes were grouped into four pairs. These were further resolved by two additional PCRs. We compared the data from PCR serotyping with conventional serotyping and found that PCR serotyping was nearly as discriminatory as conventional serotyping was. The results from a blind test screening 111 clinical isolates revealed that 97% were correctly identified using the multiplex PCR assay. The assay can be easily performed on multiple samples with final results in less than 5 h and, in conjunction with pulsed-field gel electrophoresis, forms a very robust test method for the molecular subtyping of Salmonella enterica subsp. enterica. PMID:16943358

Kim, Seonghan; Frye, Jonathan G.; Hu, Jinxin; Fedorka-Cray, Paula J.; Gautom, Romesh; Boyle, David S.

2006-01-01

378

Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology.  

PubMed

In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (10(3) CFU/g). The encapsulated probiotics were unstable when they were stored at 20 °C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 °C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at -18 °C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved. PMID:24516445

Pedroso, D L; Dogenski, M; Thomazini, M; Heinemann, R J B; Favaro-Trindade, C S

2013-01-01

379

Variants of a genomic island in Aeromonas salmonicida subsp. salmonicida link isolates with their geographical origins.  

PubMed

Aeromonas salmonicida subsp. salmonicida is a fish pathogen. Analysis of its genomic characteristics is required to determine the worldwide distribution of the various populations of this bacterium. Genomic alignments between the 01-B526 pathogenic strain and the A449 reference strain have revealed a 51-kb chromosomal insertion in 01-B526. This insertion (AsaGEI1a) has been identified as a new genomic island (GEI) bearing prophage genes. PCR assays were used to detect this GEI in a collection of 139 A. salmonicida subsp. salmonicida isolates. Three forms of this GEI (AsaGEI1a, AsaGEI1b, AsaGEI2a) are now known based on this analysis and the sequencing of the genomes of seven additional isolates. A new prophage (prophage 3) associated with AsaGEI2a was also discovered. Each GEI appeared to be strongly associated with a specific geographic region. AsaGEI1a and AsaGEI2a were exclusively found in North American isolates, except for one European isolate bearing AsaGEI2a. The majority of the isolates bearing AsaGEI1b or no GEI were from Europe. Prophage 3 has also a particular geographic distribution and was found only in North American isolates. We demonstrated that A. salmonicida subsp. salmonicida possesses unsuspected elements of genomic heterogeneity that could be used as indicators to determine the geographic origins of isolates of this bacterium. PMID:25480167

Emond-Rheault, Jean-Guillaume; Vincent, Antony T; Trudel, Mélanie V; Brochu, Francis; Boyle, Brian; Tanaka, Katherine H; Attéré, Sabrina A; Jubinville, Éric; Loch, Thomas P; Winters, Andrew D; Faisal, Mohamed; Frenette, Michel; Derome, Nicolas; Charette, Steve J

2015-01-30

380

The first structure of a mycobacteriophage, the Mycobacterium abscessus subsp. bolletii phage Araucaria.  

PubMed

The unique characteristics of the waxy mycobacterial cell wall raise questions about specific structural features of their bacteriophages. No structure of any mycobacteriophage is available, although ?3,500 have been described to date. To fill this gap, we embarked in a genomic and structural study of a bacteriophage from Mycobacterium abscessus subsp. bolletii, a member of the Mycobacterium abscessus group. This opportunistic pathogen is responsible for respiratory tract infections in patients with lung disorders, particularly cystic fibrosis. M. abscessus subsp. bolletii was isolated from respiratory tract specimens, and bacteriophages were observed in the cultures. We report here the genome annotation and characterization of the M. abscessus subsp. bolletii prophage Araucaria, as well as the first single-particle electron microscopy reconstruction of the whole virion. Araucaria belongs to Siphoviridae and possesses a 64-kb genome containing 89 open reading frames (ORFs), among which 27 could be annotated with certainty. Although its capsid and connector share close similarity with those of several phages from Gram-negative (Gram(-)) or Gram(+) bacteria, its most distinctive characteristic is the helical tail decorated by radial spikes, possibly host adhesion devices, according to which the phage name was chosen. Its host adsorption device, at the tail tip, assembles features observed in phages binding to protein receptors, such as phage SPP1. All together, these results suggest that Araucaria may infect its mycobacterial host using a mechanism involving adhesion to cell wall saccharides and protein, a feature that remains to be further explored. PMID:23678183

Sassi, Mohamed; Bebeacua, Cecilia; Drancourt, Michel; Cambillau, Christian

2013-07-01

381

Unmarked insertional mutagenesis in the bovine pathogen Mycoplasma mycoides subsp. mycoides SC  

PubMed Central

Mycoplasma mycoides subspecies mycoides small colony (SC) is the aetiologic agent of contagious bovine pleuropneumonia (CBPP), a respiratory disease causing important losses in cattle production. The publication of the genome sequence of M. mycoides subsp. mycoides SC should facilitate the identification of putative virulence factors. However, real progress in the study of molecular mechanisms of pathogenicity also requires efficient molecular tools for gene inactivation. In the present study, we have developed a transposon-based approach for the random mutagenesis of M. mycoides subsp. mycoides SC. A PCR-based screening assay enabled the characterization of several mutants with knockouts of genes potentially involved in pathogenicity. The initial transposon was further improved by combining it with the transposon ?? TnpR/res recombination system to allow the production of unmarked mutations. Using this approach, we isolated a mutant free of antibiotic-resistance genes, in which the gene encoding the main lipoprotein LppQ was disrupted. The mutant was found to express only residual amounts of the truncated N-terminal end of LppQ. This approach opens the way to study virulence factors and pathogen-host interactions of M. mycoides subsp. mycoides SC and to develop new, genetically defined vaccine strains. PMID:18667575

Janis, Carole; Bischof, Daniela; Gourgues, Géraldine; Frey, Joachim; Blanchard, Alain; Sirand-Pugnet, Pascal

2009-01-01

382

Neonatal invasive Streptococcus gallolyticus subsp. pasteurianus infection with delayed central nervous system complications  

PubMed Central

Group D streptococci are known to cause newborn septicemia and meningitis, but the Streptococcus bovis group strains rarely cause serious neonatal infections in Korea. Central nervous system (CNS) complications of neonatal S. bovis group infection have rarely been reported. In adults, S. bovis group strains cause bacteremia and endocarditis, and are associated with gastrointestinal malignancy. However, only a few studies have reported meningitis and septicemia in infants. Here, we describe a case of bacteremia and meningitis due to Streptococcus gallolyticus subsp. pasteurianus with a delayed CNS complication in an infant. A 28-day-old male infant was admitted to the hospital with a 1-day history of fever. Cultures of blood, cerebrospinal fluid, and urine showed the presence of S. bovis group strain-S. gallolyticus subsp. pasteurianus. He was discharged after 21 days of intravenous ampicillin and cefotaxime administration. Two weeks later, he was readmitted with a fever and short episodes of tonic-clonic movements. Brain magnetic resonance imaging showed marked bilateral frontal subdural effusion. He was discharged after 31 days of antibiotic therapy, and no neurological sequelae were observed at the 9-month follow-up. In conclusion, we present a rare case of neonatal S. gallolyticus subsp. pasteurianus infection causing urinary tract infection, septicemia, meningitis, and delayed CNS complications. This case emphasizes the need for physicians to be aware of S. bovis infection in infants. PMID:25729397

Park, Jung-Weon; Eun, So-Hee; Kim, Eui-Chong; Seong, Moon-Woo

2015-01-01

383

Identification and characterization of Nip, necrosis-inducing virulence protein of Erwinia carotovora subsp. carotovora.  

PubMed

Erwinia carotovora subsp. carotovora is a gram-negative bacterium that causes soft rot disease of many cultivated crops. When a collection of E. carotovora subsp. carotovora isolates was analyzed on a Southern blot using the harpin-encoding gene hrpN as probe, several harpinless isolates were found. Regulation of virulence determinants in one of these, strain SCC3193, has been characterized extensively. It is fully virulent on potato and in Arabidopsis thaliana. An RpoS (SigmaS) mutant of SCC3193, producing elevated levels of secreted proteins, was found to cause lesions resembling the hypersensitive response when infiltrated into tobacco leaf tissue. This phenotype was evident only when bacterial cells had been cultivated on solid minimal medium at low pH and temperature. The protein causing'the cell death was purified and sequenced, and the corresponding gene was cloned. The deduced sequence of the necrosis-inducing protein (Nip) showed homology to necrosis- and ethylene-inducing elicitors of fungi and oomycetes. A mutant strain of E. carotovora subsp. carotovora lacking the nip gene showed reduced virulence in potato tuber assay but was unaffected in virulence in potato stem or on other tested host plants. PMID:15597742

Mattinen, Laura; Tshuikina, Marina; Mäe, Andres; Pirhonen, Minna

2004-12-01

384

New Type of Antimicrobial Protein Produced by the Plant Pathogen Clavibacter michiganensis subsp. michiganensis  

PubMed Central

It has previously been shown that the tomato pathogen Clavibacter michiganensis subsp. michiganensis secretes a 14-kDa protein, C. michiganensis subsp. michiganensis AMP-I (CmmAMP-I), that inhibits growth of Clavibacter michiganensis subsp. sepedonicus, the causal agent of bacterial ring rot of potato. Using sequences obtained from tryptic fragments, we have identified the gene encoding CmmAMP-I and we have recombinantly produced the protein with an N-terminal intein tag. The gene sequence showed that CmmAMP-I contains a typical N-terminal signal peptide for Sec-dependent secretion. The recombinant protein was highly active, with 50% growth inhibition (IC50) of approximately 10 pmol, but was not toxic to potato leaves or tubers. CmmAMP-I does not resemble any known protein and thus represents a completely new type of bacteriocin. Due to its high antimicrobial activity and its very narrow inhibitory spectrum, CmmAMP-1 may be of interest in combating potato ring rot disease. PMID:23851100

Liu, Zhanliang; Ma, Ping; Holtsmark, Ingrid; Skaugen, Morten; Eijsink, Vincent G. H.

2013-01-01

385

Ingestion and Adsorption of Bacillus thuringiensis subsp. israelensis by Gammarus lacustris in the Laboratory.  

PubMed

Several groups of Gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of Bacillus thuringiensis subsp. israelensis per liter for 1- or 24-h periods by using traditional static bioassay exposure procedures. During a postexposure holding period, fecal pellets were removed and plated on tryptic soy agar to determine B. thuringiensis subsp. israelensis spore content. The experiments verified that traditional exposure procedures assure ingestion of B. thuringiensis subsp. israelensis spores and provided a mean dose estimate of 1,948 spores ingested per test animal with a 95% confidence interval ranging from 891 to 4,296 (1-h exposure, 5.0 mg/liter). It was also found that dose level is highly dependent upon both exposure duration and concentration and that relatively short exposures can result in a relatively long-term retention of spores postexposure (>/=30 days). Body burden experiments established that large numbers of spores adsorb to the bodies of test animals during exposure and may in part explain the long-term retention of spores in the test system postexposure. These results imply that in field applications of microbial control agents, toxicologically unaffected but exposed organisms might transport the agent to untreated sites, expanding the effective treatment area and the number of organisms exposed. PMID:16347242

Brazner, J C; Anderson, R L

1986-12-01

386

Interactions between Bacillus thuringiensis subsp. israelensis and Fathead Minnows, Pimephales promelas Rafinesque, under Laboratory Conditions  

PubMed Central

Interactions between Bacillus thuringiensis subsp. israelensis and fathead minnows, Pimephales promelas, were studied in laboratory exposures to two commercial formulations, Vectobac-G and Mosquito Attack. Mortality among fatheads exposed to 2.0 × 106 to 6.5 × 106 CFU/ml with both formulations was attributed to severe dissolved oxygen depletion due to formulation ingredients rather than to direct toxicity from the parasporal crystal. No adverse effects were observed at 6.4 × 105 CFU/ml and below. Fathead minnows rapidly accumulated high numbers of spores with 1 h of exposure to 2.2 × 105 CFU of Mosquito Attack per ml, producing whole-body counts of 4.0 × 106 CFU per fish. Comparison of counts on gastrointestinal tract samples and whole-body samples and high numbers of spores in feces indicated that ingestion was the major route of exposure. B. thuringiensis subsp. israelensis spore counts decreased rapidly after transfer of fish to clean water, with a drop of over 3 orders of magnitude in 1 day. Spores were rarely detected in fish after 8 days but were detectable in feces for over 2 weeks. These findings suggest that fish could influence the dissemination of B. thuringiensis subsp. israelensis, and possibly other microbial agents, in the aquatic environment. PMID:16348271

Snarski, Virginia M.

1990-01-01

387

Ingestion and Adsorption of Bacillus thuringiensis subsp. israelensis by Gammarus lacustris in the Laboratory  

PubMed Central

Several groups of Gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of Bacillus thuringiensis subsp. israelensis per liter for 1- or 24-h periods by using traditional static bioassay exposure procedures. During a postexposure holding period, fecal pellets were removed and plated on tryptic soy agar to determine B. thuringiensis subsp. israelensis spore content. The experiments verified that traditional exposure procedures assure ingestion of B. thuringiensis subsp. israelensis spores and provided a mean dose estimate of 1,948 spores ingested per test animal with a 95% confidence interval ranging from 891 to 4,296 (1-h exposure, 5.0 mg/liter). It was also found that dose level is highly dependent upon both exposure duration and concentration and that relatively short exposures can result in a relatively long-term retention of spores postexposure (?30 days). Body burden experiments established that large numbers of spores adsorb to the bodies of test animals during exposure and may in part explain the long-term retention of spores in the test system postexposure. These results imply that in field applications of microbial control agents, toxicologically unaffected but exposed organisms might transport the agent to untreated sites, expanding the effective treatment area and the number of organisms exposed. PMID:16347242

Brazner, John C.; Anderson, Richard L.

1986-01-01

388

Phospholipase A2 Inhibitors Synthesized by Two Entomopathogenic Bacteria, Xenorhabdus nematophila and Photorhabdus temperata subsp. temperata  

PubMed Central

The entomopathogenic bacteria Xenorhabdus nematophila and Photorhabdus temperata subsp. temperata suppress insect immune responses by inhibiting the catalytic activity of phospholipase A2 (PLA2), which results in preventing biosynthesis of immune-mediating eicosanoids. This study identified PLA2 inhibitors derived from culture broths of these two bacteria. Both X. nematophila and P. temperata subsp. temperata culture broths possessed significant PLA2-inhibitory activities. Fractionation of these bacterial metabolites in the culture broths using organic solvent and subsequent chromatography purified seven potent PLA2 inhibitors, three of which (benzylideneacetone [BZA], proline-tyrosine [PY], and acetylated phenylalanine-glycine-valine [FGV]) were reported in a previous study. Four other compounds (indole, oxindole, cis-cyclo-PY, and p-hydroxyphenyl propionic acid) were identified and shown to significantly inhibit PLA2. X. nematophila culture broth contained these seven compounds, while P. temperata subsp. temperata culture broth contained three compounds (BZA, acetylated FGV, and cis-cyclo-PY). BZA was detected in the largest amount among these PLA2 compounds in both bacterial culture broths. All seven bacterial metabolites also showed significant inhibitory activities against immune responses, such as phenoloxidase activity and hemocytic nodulation; BZA was the most potent. Finally, this study characterized these seven compounds for their insecticidal activities against the diamondback moth, Plutella xylostella. Even though these compounds showed relatively low toxicities to larvae, they significantly enhanced the pathogenicity of Bacillus thuringiensis. This study reports bacterial-origin PLA2 inhibitors, which would be applicable for developing novel insecticides. PMID:22447611

Seo, Samyeol; Lee, Sunghong; Hong, Yongpyo

2012-01-01

389

Genetic Variability and Population Structure of Disanthus cercidifolius subsp. longipes (Hamamelidaceae) Based on AFLP Analysis  

PubMed Central

Disanthus cercidifolius subsp. longipes is an endangered species in China. Genetic diversity and structure analysis of this species was investigated using amplified fragments length polymorphism (AFLP) fingerprinting. Nei's gene diversity ranged from 0.1290 to 0.1394. The AMOVA indicated that 75.06% of variation was distributed within populations, while the between-group component 5.04% was smaller than the between populations-within-group component 19.90%. Significant genetic differentiation was detected between populations. Genetic and geographical distances were not correlated. PCA and genetic structure analysis showed that populations from East China were together with those of the Nanling Range. These patterns of genetic diversity and levels of genetic variation may be the result of D. c. subsp. longipes restricted to several isolated habitats and “excess flowers production, but little fruit set”. It is necessary to protect all existing populations of D. c. subsp. longipes in order to preserve as much genetic variation as possible. PMID:25250583

Yu, Yi; Fan, Qiang; Shen, Rujiang; Guo, Wei; Jin, Jianhua; Cui, Dafang; Liao, Wenbo

2014-01-01

390

Lactobacillus delbrueckii subsp. bulgaricus CRL 454 cleaves allergenic peptides of ?-lactoglobulin.  

PubMed

Whey, a cheese by-product used as a food additive, is produced worldwide at 40.7 million tons per year. ?-Lactoglobulin (BLG), the main whey protein, is poorly digested and is highly allergenic. We aimed to study the contribution of Lactobacillus delbrueckii subsp. bulgaricus CRL 454 to BLG digestion and to analyse its ability to degrade the main allergenic sequences of this protein. Pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 increases digestion of BLG assayed by an in vitro simulated gastrointestinal system. Moreover, peptides from hydrolysis of the allergenic sequences V41-K60, Y102-R124, C121-L140 and L149-I162 were found when BLG was hydrolysed by this strain. Interestingly, peptides possessing antioxidant, ACE inhibitory, antimicrobial and immuno-modulating properties were found in BLG degraded by both the Lactobacillus strain and digestive enzymes. To conclude, pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 has a positive effect on BLG digestion and could diminish allergenic reactions. PMID:25306364

Pescuma, Micaela; Hébert, Elvira M; Haertlé, Thomas; Chobert, Jean-Marc; Mozzi, Fernanda; Font de Valdez, Graciela

2015-03-01

391

Juniperus oxycedrus L. subsp. oxycedrus and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. "berries" from Turkey: comparative evaluation of phenolic profile, antioxidant, cytotoxic and antimicrobial activities.  

PubMed

This work aimed to evaluate and compare the phenolic profile and some biological properties of the ripe "berries" methanol extracts of Juniperus oxycedrus L. subsp. oxycedrus (Joo) and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom) from Turkey. The total phenolic content resulted about 3-fold higher in Jom (17.89±0.23 mg GAE/g extract) than in Joo (5.14±0.06 mg GAE/g extract). The HPLC-DAD-ESI-MS analysis revealed a similar flavonoid fingerprint in Joo and Jom, whereas a difference in their quantitative content was found (4632 ?g/g extract and 12644 ?g/g extract). In addition, three phenolic acids were detected in Jom only (5765 ?g/g extract), and protocatechuic acid was the most abundant one. The antioxidant capacity of the extracts was evaluated by different in vitro assays: in the DPPH and in the TBA tests a stronger activity in Jom was highlighted, while Joo exhibited higher reducing power and metal chelating activity. Joo and Jom did not affect HepG2 cell viability and both extracts resulted virtually non-toxic against Artemia salina. The extracts were also studied for their antimicrobial potential, displaying efficacy against Gram-positive bacteria. PMID:23603383

Taviano, Maria Fernanda; Marino, Andreana; Trovato, Ada; Bellinghieri, Valentina; Melchini, Antonietta; Dugo, Paola; Cacciola, Francesco; Donato, Paola; Mondello, Luigi; Güvenç, Ay?egül; De Pasquale, Rita; Miceli, Natalizia

2013-08-01

392

Characterization of pathogenic vibrios isolated from bivalve hatcheries in Galicia, NW Atlantic coast of Spain. Description of Vibrio tubiashii subsp. europaensis subsp. nov.  

PubMed

The taxonomic position of the bivalve pathogen PP-638 was studied together with five similar isolates. The strains were isolated from flat oyster (Ostrea edulis) and Manila clam (Venerupis philippinarum) cultures during outbreaks of disease in two shellfish hatcheries (Galicia, NW Spain). The pathogenicity, previously established for PP-638, was demonstrated with all isolates and for several bivalve species, including the original hosts. On the basis of phenotypic characterization and 16S rRNA gene sequences, a tight group was defined within the genus Vibrio. Multilocus sequence analysis (MLSA) based on concatenated sequences of the 16S rRNA gene and the five housekeeping genes recA, rpoA, pyrH, gyrB and ftsZ revealed that these strains form a cluster within the Orientalis clade, close to the species Vibrio tubiashii. The results of MLSA, the DDH rate and the phenotypic differences with the type strain of V. tubiashii supported the differentiation of the Galician isolates as a new subspecies within V. tubiashii, for which the name V. tubiashii subsp. europaensis subsp. nov. is proposed (type strain PP-638(T)=CECT 8136(T)=DSM 7349(T)) The emended description of V. tubiashii is included. The pathogenicity assays widen the host range of V. tubiashii to add two unreported species, Venerupis decussata and Donax trunculus, and the described as relatively resistant species V. philippinarum. PMID:25555343

Prado, Susana; Dubert, Javier; Barja, Juan L

2015-02-01

393

Effect of soil slope on the appearance of Mycobacterium avium subsp. paratuberculosis in water running off grassland soil after application of contaminated slurry.  

PubMed

The study assessed the effect of soil slope on Mycobacterium avium subsp. paratuberculosis transport into rainwater runoff from agricultural soil after application of M. avium subsp. paratuberculosis-contaminated slurry. Under field conditions, 24 plots of undisturbed loamy soil 1 by 2 m(2) were placed on platforms. Twelve plots were used for water runoff: 6 plots at a 3% slope and 6 plots at a 15% slope. Half of the plots of each slope were treated with M. avium subsp. paratuberculosis-contaminated slurry, and half were not treated. Using the same experimental design, 12 plots were established for soil sampling on a monthly basis using the same spiked slurry application and soil slopes. Runoff following natural rainfall was collected and analyzed for M. avium subsp. paratuberculosis, coliforms, and turbidity. M. avium subsp. paratuberculosis was detected in runoff from all plots treated with contaminated slurry and one control plot. A higher slope (15%) increased the likelihood of M. avium subsp. paratuberculosis detection but did not affect the likelihood of finding coliforms. Daily rainfall increased the likelihood that runoff would have coliforms and the coliform concentration, but it decreased the M. avium subsp. paratuberculosis concentration in the runoff. When there was no runoff, rain was associated with increased M. avium subsp. paratuberculosis concentrations. Coliform counts in runoff were related to runoff turbidity. M. avium subsp. paratuberculosis presence/absence, however, was related to turbidity. Study duration decreased bacterial detection and concentration. These findings demonstrate the high likelihood that M. avium subsp. paratuberculosis in slurry spread on pastures will contaminate water runoff, particularly during seasons with high rainfall. M. avium subsp. paratuberculosis contamination of water has potential consequences for both animal and human health. PMID:23542616

Salgado, M; Alfaro, M; Salazar, F; Troncoso, E; Mitchell, R M; Ramirez, L; Naguil, A; Zamorano, P; Collins, M T

2013-06-01

394

Effect of Soil Slope on the Appearance of Mycobacterium avium subsp. paratuberculosis in Water Running off Grassland Soil after Application of Contaminated Slurry  

PubMed Central

The study assessed the effect of soil slope on Mycobacterium avium subsp. paratuberculosis transport into rainwater runoff from agricultural soil after application of M. avium subsp. paratuberculosis-contaminated slurry. Under field conditions, 24 plots of undisturbed loamy soil 1 by 2 m2 were placed on platforms. Twelve plots were used for water runoff: 6 plots at a 3% slope and 6 plots at a 15% slope. Half of the plots of each slope were treated with M. avium subsp. paratuberculosis-contaminated slurry, and half were not treated. Using the same experimental design, 12 plots were established for soil sampling on a monthly basis using the same spiked slurry application and soil slopes. Runoff following natural rainfall was collected and analyzed for M. avium subsp. paratuberculosis, coliforms, and turbidity. M. avium subsp. paratuberculosis was detected in runoff from all plots treated with contaminated slurry and one control plot. A higher slope (15%) increased the likelihood of M. avium subsp. paratuberculosis detection but did not affect the likelihood of finding coliforms. Daily rainfall increased the likelihood that runoff would have coliforms and the coliform concentration, but it decreased the M. avium subsp. paratuberculosis concentration in the runoff. When there was no runoff, rain was associated with increased M. avium subsp. paratuberculosis concentrations. Coliform counts in runoff were related to runoff turbidity. M. avium subsp. paratuberculosis presence/absence, however, was related to turbidity. Study duration decreased bacterial detection and concentration. These findings demonstrate the high likelihood that M. avium subsp. paratuberculosis in slurry spread on pastures will contaminate water runoff, particularly during seasons with high rainfall. M. avium subsp. paratuberculosis contamination of water has potential consequences for both animal and human health. PMID:23542616

Alfaro, M.; Salazar, F.; Troncoso, E.; Mitchell, R. M.; Ramirez, L.; Naguil, A.; Zamorano, P.; Collins, M. T.

2013-01-01

395

Biomass and nutrient content of sessile oak (Quercus petraea (Matt.) Liebl.) and beech (Fagus sylvatica L.) stem and branches in a mixed stand in southern Belgium.  

PubMed

Accurate estimates of the amounts of nutrients immobilised in the organs and tissues of different tree species are of prime importance to make appropriate tree species selection and determine the harvesting regime that will ensure forest sustainability. Sixteen sessile oaks (Quercus petraea (Matt.) Liebl.) (64-129years; stem diameters: 17-57cm) and twelve beeches (Fagus sylvatica L.) (43-86years; stem diameters: 9-50cm) were destructively sampled from a mixed stand located on an acid brown soil in southern Belgium. Statistical models were developed to investigate the differences in nutrient concentrations between tree species, between aboveground tree compartments of the same species, and between tissues of the same compartment. For stem tissues, vertical concentration profiles were described using a versatile equation. Allometric equations were used to predict biomass and nutrient content of tree compartments based on tree dimensions. Broadly speaking, nutrient concentrations tended to be somewhat higher for oak compared with beech, but the amplitude and the direction of inter-species differences varied greatly, depending on the nutrient and the tree compartment. For both species, living branch nutrient concentrations tended to decrease with increasing branch diameter, except for Ca (oak) and Mg (beech). Nutrient concentrations were consistently higher in bark than in wood; this difference between tissues was quite pronounced for Ca, particularly in the case of oak. The biomass and nutrient content equations were used to investigate the effects of tree species and harvesting regime on nutrient exports at harvesting. For equivalent harvesting scenarios, beech was found to induce higher Mg exports than oak, and inversely for Ca. Assuming stand clear cutting, complete tree harvesting would increase average nutrient exports from 65% (Ca) to 162% (P) compared with a stem-only harvesting scenario. These results provide valuable information in the current context of the more intensive utilization of forest products. PMID:20231032

André, Frédéric; Jonard, Mathieu; Ponette, Quentin

2010-05-01

396

Growth of adult Norway spruce (Picea abies [L.] Karst.) and European beech (Fagus sylvatica L.) under free-air ozone fumigation.  

PubMed

This study attempted to detect the impact of ozone on adult trees of Norway spruce ( Picea abies [L.] Karst.) and European beech ( Fagus sylvatica L.) in an experimental mixed stand in Southern Bavaria, Germany. The aim was to examine whether there is a decrease in growth when trees are exposed to higher than atmospheric concentrations of ozone. This exposure was put into effect using a free-air fumigation system at tree crown level. Growth analysis was carried out on a group of 47 spruce and 36 beech trees, where radial stem increment at breast height - a sensitive index for stress - was measured. The ozone monitoring system allowed values to be obtained for the accumulated ozone exposure (SUM00) of each individual tree, so that their radial increment over three years could be correlated with the corresponding ozone exposure for the same time period. Correlation and regression analysis were then carried out to test the influence of ozone on diameter increment. In both spruce and beech, the initial stem diameter was the most influential factor on radial increment in the following year. A linear model was applied, including the diameter of the preceding year and the ozone exposure of the current year as predicting factors. For spruce trees, a significant negative influence of ozone exposure was found. In contrast, no significant ozone effect on diameter increment of beech was detected. The effect of ozone stress on a large spruce tree can lead to a decrease in potential radial increment of 22 %. The results are discussed in relation to other stress factors such as drought and lack of light. PMID:16388464

Wipfler, P; Seifert, T; Heerdt, C; Werner, H; Pretzsch, H

2005-11-01

397

Effects of long-term exposure to ammonium sulfate particles on growth and gas exchange rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica seedlings  

NASA Astrophysics Data System (ADS)

To clarify the effects of long-term exposure to ammonium sulfate (AS) particles on growth and physiological functions of forest tree species, seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron-size AS particles during two growing seasons from 3 June 2011 to 8 October 2012. The mean sulfate concentration in PM2.5 increased during the exposure inside the chamber in 2011 and 2012 by 2.73 and 4.32 ?g SO42- m-3, respectively. No significant effects of exposure to AS particles were detected on the whole-plant dry mass of the seedlings. These results indicate that the exposure to submicrometer AS particles at the ambient level for two growing seasons did not significantly affect the growth of the seedlings. No significant effects of exposure to AS particles were found on the net photosynthetic rate in the leaves or needles of F. crenata, C. sieboldii and L. kaempferi seedlings. Also, in the previous-year needles of C. japonica seedlings, exposure to AS particles significantly reduced the net photosynthetic rate, which may be caused by the reduction in the concentration of ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco). On the contrary, in current-year needles of C. japonica seedlings, net photosynthetic rate significantly increased with exposure to AS particles, which may be the result of increases in stomatal conductance and concentrations of Rubisco and chlorophyll. Furthermore, exposure to AS particles correlated with an increase in concentrations of NH4+, free amino acid and total soluble protein, suggesting that AS particles may be deliquesced, absorbed into the leaves and metabolized into amino acid and protein. These results suggest that net photosynthesis in the needles of C. japonica is relatively sensitive to submicron-size AS particles as compared with the other three tree species.

Yamaguchi, Masahiro; Otani, Yoko; Li, Peiran; Nagao, Hiroshi; Lenggoro, I. Wuled; Ishida, Atsushi; Yazaki, Kenichi; Noguchi, Kyotaro; Nakaba, Satoshi; Yamane, Kenichi; Kuroda, Katsushi; Sano, Yuzou; Funada, Ryo; Izuta, Takeshi

2014-11-01

398

Within-Population Genetic Structure in Beech (Fagus sylvatica L.) Stands Characterized by Different Disturbance Histories: Does Forest Management Simplify Population Substructure?  

PubMed Central

The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which has strong implications for the potential of forests to adapt to environmental change. The present study was aimed at comparing within-population genetic structure in European beech (Fagus sylvatica L.) plots experiencing different disturbance levels. Five plot pairs made up by disturbed and undisturbed plots having the same biogeographic history were sampled throughout Europe. Overall, 1298 individuals were analyzed using four highly polymorphic nuclear microsatellite markers (SSRs). Bayesian clustering within plots identified 3 to 11 genetic clusters (within-plot ?ST ranged from 0.025 to 0.124). The proportion of within-population genetic variation due to genetic substructuring (FCluPlot?=?0.067) was higher than the differentiation among the 10 plots (FPlotTot?=?0.045). Focusing on the comparison between managed and unmanaged plots, disturbance mostly explains differences in the complexity of within-population genetic structure, determining a reduction of the number of genetic clusters present in a standardized area. Our results show that: i) genetic substructuring needs to be investigated when studying the within-population genetic structure in forest tree populations, and ii) indices describing subtle characteristics of the within-population genetic structure are good candidates for providing early signals of the consequences of forest management, and of disturbance events in general. PMID:24039930

Piotti, Andrea; Leonardi, Stefano; Heuertz, Myriam; Buiteveld, Joukje; Geburek, Thomas; Gerber, Sophie; Kramer, Koen; Vettori, Cristina; Vendramin, Giovanni Giuseppe

2013-01-01

399

Patterns of late spring frost leaf damage and recovery in a European beech (Fagus sylvatica L.) stand in south-eastern Germany based on repeated digital photographs.  

PubMed

Damage by late spring frost is a risk deciduous trees have to cope with in order to optimize the length of their growing season. The timing of spring phenological development plays a crucial role, not only at the species level, but also at the population and individual level, since fresh new leaves are especially vulnerable. For the pronounced late spring frost in May 2011 in Germany, we studied the individual leaf development of 35 deciduous trees (mainly European beech Fagus sylvatica L.) at a mountainous forest site in the Bayerischer Wald National Park using repeated digital photographs. Analyses of the time series of greenness by a novel Bayesian multiple change point approach mostly revealed five change points which almost perfectly matched the expected break points in leaf development: (i) start of the first greening between day of the year (DOY) 108-119 (mean 113), (ii) end of greening, and (iii) visible frost damage after the frost on the night of May 3rd/4th (DOY 123/124), (iv) re-sprouting 19-38 days after the frost, and (v) full maturity around DOY 178 (166-184) when all beech crowns had fully recovered. Since frost damage was nearly 100%, individual susceptibility did not depend on the timing of first spring leaf unfolding. However, we could identify significant patterns in fitness linked to an earlier start of leaf unfolding. Those individuals that had an earlier start of greening during the first flushing period had a shorter period of recovery and started the second greening earlier. Thus, phenological timing triggered the speed of recovery from such an extreme event. The maximum greenness achieved, however, did not vary with leaf unfolding dates. Two mountain ashes (Sorbus aucuparia L.) were not affected by the low temperatures of -5°C. Time series analysis of webcam pictures can thus improve process-based knowledge and provide valuable insights into the link between phenological variation, late spring frost damage, and recovery within one stand. PMID:25759707

Menzel, Annette; Helm, Raimund; Zang, Christian

2015-01-01

400

Patterns of late spring frost leaf damage and recovery in a European beech (Fagus sylvatica L.) stand in south-eastern Germany based on repeated digital photographs  

PubMed Central

Damage by late spring frost is a risk deciduous trees have to cope with in order to optimize the length of their growing season. The timing of spring phenological development plays a crucial role, not only at the species level, but also at the population and individual level, since fresh new leaves are especially vulnerable. For the pronounced late spring frost in May 2011 in Germany, we studied the individual leaf development of 35 deciduous trees (mainly European beech Fagus sylvatica L.) at a mountainous forest site in the Bayerischer Wald National Park using repeated digital photographs. Analyses of the time series of greenness by a novel Bayesian multiple change point approach mostly revealed five change points which almost perfectly matched the expected break points in leaf development: (i) start of the first greening between day of the year (DOY) 108–119 (mean 113), (ii) end of greening, and (iii) visible frost damage after the frost on the night of May 3rd/4th (DOY 123/124), (iv) re-sprouting 19–38 days after the frost, and (v) full maturity around DOY 178 (166–184) when all beech crowns had fully recovered. Since frost damage was nearly 100%, individual susceptibility did not depend on the timing of first spring leaf unfolding. However, we could identify significant patterns in fitness linked to an earlier start of leaf unfolding. Those individuals that had an earlier start of greening during the first flushing period had a shorter period of recovery and started the second greening earlier. Thus, phenological timing triggered the speed of recovery from such an extreme event. The maximum greenness achieved, however, did not vary with leaf unfolding dates. Two mountain ashes (Sorbus aucuparia L.) were not affected by the low temperatures of -5°C. Time series analysis of webcam pictures can thus improve process-based knowledge and provide valuable insights into the link between phenological variation, late spring frost damage, and recovery within one stand. PMID:25759707

Menzel, Annette; Helm, Raimund; Zang, Christian

2015-01-01

401

Spatial vs. temporal effects on demographic and genetic structures: the roles of dispersal, masting and differential mortality on patterns of recruitment in Fagus sylvatica.  

PubMed

Trees' long lifespan, long-distance dispersal abilities and high year-to-year variability in fecundity are thought to have pervasive consequences for the demographic and genetic structure of recruited seedlings. However, we still lack experimental studies quantifying the respective roles of spatial processes such as restricted seed and pollen dispersal and temporal processes such as mast seeding on patterns of regeneration. Dynamics of European beech (Fagus sylvatica) seedling recruitment was monitored in three plots from 2004 to 2006. Six polymorphic microsatellite genetic markers were used to characterize seedlings and their potential parents in a 7.2-ha stand. These seedlings were shown to result from 12 years of recruitment, with one predominant year of seedling recruitment in 2002 and several years without significant recruitment. Using a spatially explicit mating model based on parentage assignment, short average dispersal distances for seed (?(s) = 10.9 m) and pollen (43.7 m < ?(p) <57.3 m) were found, but there was also a non-negligible immigration rate from outside the plot (m(s) = 20.5%; 71.6% < m(p) < 77.9%). Hierarchical analyses of seedling genetic structure showed that (i) most of the genetic variation was within plots; (ii) the genetic differentiation among seedling plots was significant (F(ST) = 2.6%) while (iii) there was no effect of year-to-year seed rain variation on genetic structure. In addition, no significant effect of genetic structure on mortality was detected. The consequences of these results for the prediction of population dynamics at ecological timescales are discussed. PMID:21426434

Oddou-Muratorio, Sylvie; Klein, Etienne K; Vendramin, Giovanni G; Fady, Bruno

2011-05-01

402

Light and competition gradients fail to explain the coexistence of shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings  

PubMed Central

Background and Aims The coexistence of forest tree species has often been linked to differences among species in terms of their response to light availability during the regeneration stage. From this perspective, species coexistence results from growth–growth or mortality–growth trade-offs along spatial light gradients. Experimental evidence of growth–growth trade-offs in natural conditions is sparse due to various confounding factors that potentially hinder the relationship. This study examined growth hierarchies along light gradients between two tree species with contrasting shade tolerance by controlling potential confounding factors such as seedling size, seedling status, seedling density and species composition. Methods Natural regenerated shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings were used, and growth rankings over a 4-year period were compared in 8- to 10-year-old tree seedlings. Key results No rank reversal occurs between the two species along the light gradient, or along the density, mixture or seedling size gradients. The shade-tolerant species was always the more competitive of the two. Pronounced effects of initial size on seedling growth were observed, whereas the effects of light and competition by neighbours were of secondary importance. The paramount effect of size, which results from the asymmetric nature of interseedling competition, gives a strong advantage to tall seedlings over the long term. Conclusions This study extends previous efforts to identify potential drivers of rank reversals in young tree mixtures. It does not support the classical assumption that spatial heterogeneity in canopy opening explains the coexistence of the two species studied. It suggests that spatial variation in local size hierarchies among seedlings that may be caused by seedling emergence time or seedling initial performance is the main driver of the dynamics of these mixed stands. PMID:24036670

Van Couwenberghe, Rosalinde; Gégout, Jean-Claude; Lacombe, Eric; Collet, Catherine

2013-01-01

403

The production, localization and spreading of reactive oxygen species contributes to the low vitality of long-term stored common beech (Fagus sylvatica L.) seeds.  

PubMed

The common beech (Fagus sylvatica L.) is propagated by seeds, but the seed set is irregular with five to ten years in between crops. It is therefore necessary to store the seeds. However, beech seeds lose germinability during long-term storage. In this study, beech seeds were stored at -10°C under controlled conditions for 2, 5, 8, 11 and 13 years. Our results show that beech seeds lose germinability during storage in proportion to the duration of storage. The decrease in germinability correlated with increased electrolyte leakage and accumulation of superoxide anion radicals, hydrogen peroxide and hydroxyl radicals. Furthermore, a strong positive correlation was observed among the releases of superoxide anion radicals, hydrogen peroxide and hydroxyl radicals. In situ localization showed that superoxide anion radicals and hydrogen peroxide were first detectable in root cap cells. When the seed storage time was extended, the reactive oxygen species fluorescence expanded to more areas of the radicle, reaching the root apical meristem. A storage time-dependent decrease in catalase activity, observed in both embryonic axes and cotyledons, was also positively correlated with germinability. DNA fragmentation was observed in beech seeds during storage and occurred predominantly in embryonic axes stored for 5 years and more. Altogether, these results suggest that the loss of germinability in beech seeds during long-term storage depends on several factors, including strong of reactive oxygen species accumulation accompanied by reduced catalase activity as well as membrane injury and DNA alternations, which may be aging-related and ROS-derived. We suggest that the accumulating reactive oxygen species that spread to the root apical meristem are key factors that affect seed germinability after long-term storage. PMID:25462977

Ratajczak, Ewelina; Ma?ecka, Arleta; Bagniewska-Zadworna, Agnieszka; Kalemba, Ewa Marzena

2015-02-01

404

Novel Feature of Mycobacterium avium subsp. paratuberculosis, Highlighted by Characterization of the Heparin-Binding Hemagglutinin Adhesin  

PubMed Central

Mycobacterium avium subsp. paratuberculosis comprises two genotypically defined groups, known as the cattle (C) and sheep (S) groups. Recent studies have reported phenotypic differences between M. avium subsp. paratuberculosis groups C and S, including growth rates, infectivity for macrophages, and iron metabolism. In this study, we investigated the genotypes and biological properties of the virulence factor heparin-binding hemagglutinin adhesin (HBHA) for both groups. In Mycobacterium tuberculosis, HBHA is a major adhesin involved in mycobacterium-host interactions and extrapulmonary dissemination of infection. To investigate HBHA in M. avium subsp. paratuberculosis, we studied hbhA polymorphisms by fragment analysis using the GeneMapper technology across a large collection of isolates genotyped by mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) and IS900 restriction fragment length polymorphism (RFLP-IS900) analyses. Furthermore, we analyzed the structure-function relationships of recombinant HBHA proteins of types C and S by heparin-Sepharose chromatography and surface plasmon resonance (SPR) analyses. In silico analysis revealed two forms of HBHA, corresponding to the prototype genomes for the C and S types of M. avium subsp. paratuberculosis. This observation was confirmed using GeneMapper on 85 M. avium subsp. paratuberculosis strains, including 67 strains of type C and 18 strains of type S. We found that HBHAs from all type C strains contain a short C-terminal domain, while those of type S present a long C-terminal domain, similar to that produced by Mycobacterium avium subsp. avium. The purification of recombinant HBHA from M. avium subsp. paratuberculosis of both types by heparin-Sepharose chromatography highlighted a correlation between their affinities for heparin and the lengths of their C-terminal domains, which was confirmed by SPR analysis. Thus, types C and S of M. avium subsp. paratuberculosis may be distinguished by the types of HBHA they produce, which differ in size and adherence properties, thereby providing new evidence that strengthens the genotypic differences between the C and S types of M. avium subsp. paratuberculosis. PMID:23974028

Lefrancois, Louise H.; Bodier, Christelle C.; Cochard, Thierry; Canepa, Sylvie; Raze, Dominique; Lanotte, Philippe; Sevilla, Iker A.; Stevenson, Karen; Behr, Marcel A.; Locht, Camille

2013-01-01

405

e-GTRSRS101Proceedings of the 15th Central Hardwood Forest Conference LAND-USE HISTORY AND RESULTING FOREST  

E-print Network

on forest development in the Ozark Hills of southern Illinois. By incorporating land-use history research the expansion of sugar maple (Acer saccharum M.) and American beech (Fagus grandifolia Ehrh.) onto rich upland the presettlement oak-hickory forest type to a later successional sugar maple-beech forest type. INTRODUCTION Land

406

Late Holocene Decline of Beech Populations in the Central Great Lakes Region: Drought Induced Vegetation Change in a Humid Region  

Microsoft Academic Search

A large decline in beech populations ( Fagus grandifolia) has been well-documented from pollen records in southeastern Michigan and Southern Ontario between 1000 and 600 BP. These records reveal that declines in beech pollen were generally associated with increases in oak ( Quercus) and pine ( Pinus). The beech decline probably extended eastward into western Pennsylvania and New York, although

R. K. Booth; S. T. Jackson; M. Taylor; E. Pendall; V. A. Sousa

2007-01-01

407

Hemlock Tsuga canadensis Yellow Birch Betula alleghaniensis  

E-print Network

saccharum Beech Fagus grandifolia Cedar Thuja occidentalis Tamarack Larix laricina Jack Pine Pinus banksiana Red Pine Pinus resinosa White Pine Pinus strobus Red Oak Quercus rubra Black Oak Quercus velutina No Data WISCONSIN'S 1832-1866 PUB-CE-4017 2009 Tree labels below indicate the dominant and most abundant

Mladenoff, David

408

Changes in Presettlement Forest Composition for Five Areas in the Central Hardwood Forest, 1784-1990  

Microsoft Academic Search

Witness tree tallies from early land surveys show that presettlement forests in eastern Ohio, southwestern Pennsylvania, and north central West Virginia were oak-dominated forests. Quercus alba was dominant by a large margin - at minimum, twice as abundant as Q. velutina, the second ranked species. Acer saccharum and Fagus grandifolia were among the top ten ranked species at each site;

James S. Rentch; Ray R. Hicks

409

Replacement Patterns of Beech and Sugar Maple in Warren Woods, Michigan Author(s): Thomas L. Poulson and William J. Platt  

E-print Network

Replacement Patterns of Beech and Sugar Maple in Warren Woods, Michigan Author(s): Thomas L PATTERNS OF BEECH AND SUGAR MAPLE IN WARREN WOODS, MICHIGAN1 THOMAS L. POULSON Department of Biological beech (Fagus grandifolia) and sugar maple (Acer saccharum). Our goal was to distinguish among four

Cochran-Stafira, D. Liane

410

The first host records for the Nearctic species Triraphis discoideus (Hymenoptera: Braconidae: Rogadinae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Limacodid larvae were collected from 2004 – 2007 on leaves of the following host plants in the District of Columbia and Maryland: Carya glabra, pignut hickory; Quercus alba, white oak; Quercus rubra, northern red oak; Nyssa sylvatica, black gum; Prunus serotina, black cherry; and Fagus grandifolia, ...

411

Impacts of contrasting land-use history on composition, soils, and development of mixed-oak, coastal plain forests on Shelter  

E-print Network

and successional pathways. Randomly located plots were sampled for vegetation and soils in the unplowed interior are dominated by Q. velutina, Acer rubrum, C. glabra, and Q. prinus. The interior forest plots appear to have forest exhibits a predictable successional pathway from mixed-oak to A. rubrum and Fagus grandifolia

Abrams, Marc David

412

Nitrogen cycling in a northern hardwood forest: Do species matter?  

Microsoft Academic Search

To investigate the influence of individual tree species on nitrogen (N) cycling in forests, we measured key characteristics of the N cycle in small single-species plots of five dominant tree species in the Catskill Mountains of New York State. The species studied were sugar maple (Acer saccharum), American beech (Fagus grandifolia), yellow birch (Betula alleghaniensis), eastern hemlock (Tsuga canadensis), and

Gary M. Lovett; Kathleen C. Weathers; Mary A. Arthur; Jack C. Schultz

2004-01-01

413

Emulsifying, rheological and physicochemical properties of exopolysaccharide produced by Bifidobacterium longum subsp. infantis CCUG 52486 and Bifidobacterium infantis NCIMB 702205.  

PubMed

The rheological, emulsification and certain physicochemical properties of purified exopolysaccharides (EPS) of Bifidobacterium longum subsp. infantis CCUG 52486 and Bifidobacterium infantis NCIMB 702205 were studied and compared with those of guar gum and xanthan gum. The two strains were grown in skim milk supplemented with 1.5% (w/v) casein hydrolysate at 37 °C for 24h; they both produced heteropolysaccharides with different molecular mass and composition. The carbohydrate content of both polymers was more than 92% and no protein was detected. The EPS of B. longum subsp. infantis CCUG 52486 showed highly branched entangled porous structure under scanning electron microscopy. Higher intrinsic viscosity was observed for the EPS of B. longum subsp. infantis CCUG 52486 compared to the EPS of B. infantis NCIMB 702205 and guar gum. Both polymers showed pseudoplastic non-Newtonian fluid behaviour in an aqueous solution. The EPS of B. infantis NCIMB 702205 and B. longum subsp. infantis CCUG 52486 produced more stable emulsions with orange oil, sunflower seed oil, coconut oil and xylene compared to guar and xanthan gum. The EPS of B. longum subsp. infantis CCUG 52486 is the most promising one for applications in the food industry, as it had higher intrinsic viscosity, higher apparent viscosity in aqueous solution, porous dense entangled structure and good emulsification activity. PMID:24751074

Prasanna, P H P; Bell, A; Grandison, A S; Charalampopoulos, D

2012-09-01

414

Silencing of host basal defense response-related gene expression increases susceptibility of Nicotiana benthamiana to Clavibacter michiganensis subsp. michiganensis.  

PubMed

Clavibacter michiganensis subsp. michiganensis is an actinomycete, causing bacterial wilt and canker disease of tomato (Solanum lycopersicum). We used virus-induced gene silencing (VIGS) to identify genes playing a role in host basal defense response to C. michiganensis subsp. michiganensis infection using Nicotiana benthamiana as a model plant. A preliminary VIGS screen comprising 160 genes from tomato known to be involved in defense-related signaling identified a set of 14 genes whose suppression led to altered host-pathogen interactions. Expression of each of these genes and three additional targets was then suppressed in larger-scale VIGS experiments and the effect of silencing on development of wilt disease symptoms and bacterial growth during an N. benthamiana-C. michiganensis subsp. michiganensis compatible interaction was determined. Disease susceptibility and in planta bacterial population size were enhanced by silencing genes encoding N. benthamiana homologs of ubiquitin activating enzyme, snakin-2, extensin-like protein, divinyl ether synthase, 3-hydroxy-3-methylglutaryl-coenzyme A reductase 2, and Pto-like kinase. The identification of genes having a role in the host basal defense-response to C. michiganensis subsp. michiganensis advances our understanding of the plant responses activated by C. michiganensis subsp. michiganensis and raises possibilities for devising novel and effective molecular strategies to control bacterial canker and wilt in tomato. PMID:21062112

Balaji, Vasudevan; Sessa, Guido; Smart, Christine D

2011-03-01

415

Cloning and sequence analysis of a protective M-like protein gene from Streptococcus equi subsp. zooepidemicus.  

PubMed Central

Streptococcus equi subsp. zooepidemicus, a Lancefield group C streptococcus, is a frequently isolated opportunist pathogen from a variety of animal hosts, including the horse. Previous studies have indicated that equine strains carry antigens with characteristics of the antiphagocytic M proteins on the Lancefield groups A and G streptococci. We have cloned a protective M-like protein gene (SzPW60) of an equine strain of S. equi subsp. zooepidemicus W60 and determined its sequence. This gene encodes a protein with a molecular weight of 40,123 which protects mice against subsp. zooepidemicus but not subsp. equi, stimulates antibodies which opsonize subsp. zooepidemicus but not equi, and reacts with antiserum to the protein of the parent strain. The predicted amino acid structure shows significant homology with the carboxy termini of groups A and G M proteins but no other homology. The M-like protein, although showing an extensive region of alpha helix, lacks the A, B, and C repeats found in group A M proteins and has a shorter signal sequence. A proline-rich region upstream from the LPSTGE motif contains 20 repeats of the tetrapeptide PEPK. The presence of this repeat region may account for the slow migration of the M-like protein in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. PMID:7890407

Timoney, J F; Walker, J; Zhou, M; Ding, J

1995-01-01

416

Bifidobacterium longum subsp. longum Exo-?-1,3-Galactanase, an Enzyme for the Degradation of Type II Arabinogalactan  

PubMed Central

Type II arabinogalactan (AG-II) is a suitable carbohydrate source for Bifidobacterium longum subsp. longum, but the degradative enzymes have never been characterized. In this study, we characterized an exo-?-1,3-galactanase, BLLJ_1840, belonging to glycoside hydrolase family 43 from B. longum subsp. longum JCM1217. The recombinant BLLJ_1840 expressed in Escherichia coli hydrolyzed ?-1,3-linked galactooligosaccharides but not ?-1,4- and ?-1,6-linked galactooligosaccharides. The enzyme also hydrolyzed larch wood arabinogalactan (LWAG), which comprises a ?-1,3-linked galactan backbone with ?-1,6-linked galactan side chains. The kcat/Km ratio of dearabinosylated LWAG was 24-fold higher than that of ?-1,3-galactan. BLLJ_1840 is a novel type of exo-?-1,3-galactanase with a higher affinity for the ?-1,6-substituted ?-1,3-galactan than for nonsubstituted ?-1,3-galactan. BLLJ_1840 has 27% to 28% identities with other characterized exo-?-1,3-galactanases from bacteria and fungi. The homologous genes are conserved in several strains of B. longum subsp. longum and B. longum subsp. infantis but not in other bifidobacteria. Transcriptional analysis revealed that BLLJ_1840 is intensively induced with BLLJ_1841, an endo-?-1,6-galactanase candidate, in the presence of LWAG. This is the first report of exo-?-1,3-galactanase in bifidobacteria, which is an enzyme used for the acquisition of AG-II in B. longum subsp. longum. PMID:24837371

Sakaguchi, Takenori; Sakamoto, Ayami; Shimokawa, Michiko; Kitahara, Kanefumi

2014-01-01

417

Prevalence and Acquisition of the Genes for Zoocin A and Zoocin A Resistance in Streptococcus equi subsp. zooepidemicus  

PubMed Central

Zoocin A is a streptococcolytic enzyme produced by Streptococcus equi subsp. zooepidemicus strain 4881. The zoocin A gene (zooA) and the gene specifying resistance to zoocin A (zif) are adjacent on the chromosome and are divergently transcribed. Twenty-four S. equi subsp. zooepidemicus strains were analyzed to determine the genetic difference between three previously characterized as zoocin A producers (strains 4881, 9g and 9h) and the twenty-one non-producers. LT-PCR and Southern hybridization studies revealed that none of the non-producer strains possessed zooA or zif. RAPD and PFGE showed that the 24 strains were a genetically diverse population with 8 RAPD profiles. S. equi subsp. zooepidemicus strains 9g and 9h appeared genetically identical to each other, but quite different from 4881. Sequences derived from 4881 and 9g showed that zooA and zif were integrated into the chromosome adjacent to the gene flaR. A comparison of these sequences with the genome sequences of S. equi subsp. zooepidemicus strains H70 and MGCS10565 and S. equi subsp. equi strain 4047 suggests that flaR flanks a region of genome plasticity in this species. PMID:19357799

O’Rourke, Anna-Lee D.; Simmonds, Robin S.; Gargis, Amy S.; Sloan, Gary L.

2009-01-01

418

La presenza di colesterolo nella frazione sterolica dell'olio dei semi di Solanum nigrum L. subsp. nigrum e Solanum dulcamara L  

Microsoft Academic Search

The presence of cholesterol in the sterolic fraction in the oil of the seeds of Solanum nigrum L. subsp. nigrum and Solanum dulcamara L.—The sterol fraction of oil in Solanum nigrum L. subsp. nigrum and Solanum dulcamara L. seeds has been analysed by GLC. The amounts of cholesterol we have found are 8% and 23% respectively, in relation to the

Paola Gastaldo; Paola Profumo; Enrico Tiscornia; Maria Angela Pagano

1977-01-01

419

Whole-Genome Sequencing of Mycoplasma mycoides subsp. mycoides Italian Strain 57/13, the Causative Agent of Contagious Bovine Pleuropneumonia  

PubMed Central

Mycoplasma mycoides subsp. mycoides is generally considered one of most pathogenic Mycoplasma species, and it is the etiological agent of contagious bovine pleuropneumonia (CBPP). Here, we present the annotated genome sequence of M. mycoides subsp. mycoides Italian strain 57/13, isolated in 1992 during CBPP outbreaks in Italy. PMID:25814605

Orsini, M.; Krasteva, I.; Marcacci, M.; Ancora, M.; Ciammaruconi, A.; Gentile, B.; Lista, F.; Pini, A.; Scacchia, M.; Sacchini, F.

2015-01-01

420

Persistence and Decontamination of Bacillus atrophaeus subsp. globigii Spores on Corroded Iron in a Model Drinking Water System?  

PubMed Central

Persistence of Bacillus atrophaeus subsp. globigii spores on corroded iron coupons in drinking water was studied using a biofilm annular reactor. Spores were inoculated at 106 CFU/ml in the dechlorinated reactor bulk water. The dechlorination allowed for observation of the effects of hydraulic shear and biofilm sloughing on persistence. Approximately 50% of the spores initially adhered to the corroded iron surface were not detected after 1 month. Addition of a stable 10 mg/liter free chlorine residual after 1 month led to a 2-log10 reduction of adhered B. atrophaeus subsp. globigii, but levels on the coupons quickly stabilized thereafter. Increasing the free chlorine concentration to 25 or 70 mg/liter had no additional effect on inactivation. B. atrophaeus subsp. globigii spores injected in the presence of a typical distribution system chlorine residual (?0.75 mg/liter) resulted in a steady reduction of adhered B. atrophaeus subsp. globigii over 1 month, but levels on the coupons eventually stabilized. Adding elevated chlorine levels (10, 25, and 70 mg/liter) after 1 month had no effect on the rate of inactivation. Decontamination with elevated free chlorine levels immediately after spore injection resulted in a 3-log10 reduction within 2 weeks, but the rate of inactivation leveled off afterward. This indicates that free chlorine did not reach portions of the corroded iron surface where B. atrophaeus subsp. globigii spores had adhered. B. atrophaeus subsp. globigii spores are capable of persisting for an extended time in the presence of high levels of free chlorine. PMID:17308186

Szabo, Jeffrey G.; Rice, Eugene W.; Bishop, Paul L.

2007-01-01

421

Transcriptome-Based Characterization of Interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in Lactose-Grown Chemostat Cocultures  

PubMed Central

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus, two microorganisms that co-occur in kefir fermentations, were studied during anaerobic growth on lactose. By combining physiological and transcriptome analysis of the two strains in the cocultures, five mechanisms of interaction were identified. (i) Lb. delbrueckii subsp. bulgaricus hydrolyzes lactose, which cannot be metabolized by S. cerevisiae, to galactose and glucose. Subsequently, galactose, which cannot be metabolized by Lb. delbrueckii subsp. bulgaricus, is excreted and provides a carbon source for yeast. (ii) In pure cultures, Lb. delbrueckii subsp. bulgaricus grows only in the presence of increased CO2 concentrations. In anaerobic mixed cultures, the yeast provides this CO2 via alcoholic fermentation. (iii) Analysis of amino acid consumption from the defined medium indicated that S. cerevisiae supplied alanine to the bacterium. (iv) A mild but significant low-iron response in the yeast transcriptome, identified by DNA microarray analysis, was consistent with the chelation of iron by the lactate produced by Lb. delbrueckii subsp. bulgaricus. (v) Transcriptome analysis of Lb. delbrueckii subsp. bulgaricus in mixed cultures showed an overrepresentation of transcripts involved in lipid metabolism, suggesting either a competition of the two microorganisms for fatty acids or a response to the ethanol produced by S. cerevisiae. This study demonstrates that chemostat-based transcriptome analysis is a powerful tool to investigate microbial interactions in mixed populations. PMID:23872557

Mendes, Filipa; Sieuwerts, Sander; de Hulster, Erik; Almering, Marinka J. H.; Luttik, Marijke A. H.; Pronk, Jack T.; Smid, Eddy J.; Bron, Peter A.

2013-01-01

422

Phytochemical Composition and Antinociceptive Activity of Bauhinia glauca subsp. hupehana in Rats  

PubMed Central

In traditional medicine, Bauhinia glauca subsp. hupehana has long been used as an analgesic agent in China. The aim of this study was to evaluate the antinociceptive activity of the ethanol extract of the aerial parts of B. glauca subsp. hupehana (BHE) in rats and its chemical fingerprint. The antinociceptive activity of BHE was assessed in mice using chemically and heat–induced pain models, such as the acetic acid–induced writhing, hot plate, tail–flick and glutamate tests. Naltrexone hydrochloride, a non–selective opioid receptor antagonist, was utilized to determine the involvement of the opioid system. In addition to this, the involvements of the cGMP and ATP–sensitive K+ channel pathways were also detected using methylene blue and glibenclamide. The oral administration of BHE (at doses of 50, 100 and 200 mg/kg) produced significant and dose–related inhibitions in both the chemically and heat–induced pain models. Interestingly, in the abdominal constriction test, when the dose of BHE was increased to 800 mg/kg (p.o., n = 10), the inhibition rate was 100%. The antinociceptive mechanism may involve the cGMP pathway and ATP sensitive K+ channel pathway. The central antinociceptive effect was not antagonized by naltrexone. One phenolic acid, one lignin and five flavonoids were isolated from BHE. The antinociceptive activity of BHE was most likely due to the presence of the flavonoids. The acute toxicity results showed that BHE was safe at a high dose (2 g/kg, p.o.). The current investigation demonstrates that B. glauca subsp. hupehana is a potential candidate for the development of novel, non–opioid, analgesic phytomedicines. PMID:25658740

Xu, Jinlong; Zhao, Qizhi; Wei, Lei; Yang, Yu; Xu, Rui; Yu, Nengjiang; Zhao, Yimin

2015-01-01

423

Molecular characterization of the nisin resistance region of Lactococcus lactis subsp. lactis biovar diacetylactis DRC3.  

PubMed Central

The nisin resistance determinant of Lactococcus lactis subsp. lactis biovar diacetylactis DRC3 was localized onto a 1.3-kb EcoRI-NdeI fragment by subcloning and interrupting the NdeI site by cloning random NdeI fragments into it; the nisin resistance determinant was then sequenced. The nucleotide sequence revealed a large open reading frame containing 318 codons. Putative transcription and translation signal sequences were located directly upstream from the initiation codon. Immediately downstream of the termination codon was a palindromic region resembling a rho-independent termination sequence. This 957-nucleotide open reading frame and its associated transcription and translation signal sequences were cloned into plasmid-free L. lactis subsp. lactis LM0230 and conferred an MIC of 160 IU of nisin per ml. This level of nisin resistance is equivalent to that of the initial nisin-resistant subclone, pFM011, used for further subcloning in this study. The inferred amino acid sequence would result in a protein with a molecular mass of 35,035 Da. This value was in agreement with the molecular mass of a protein detected after in vitro transcription and translation of DNA encoding the nisin resistance gene, nsr. This protein contained a hydrophobic region at the N terminus that was predicted to be membrane associated but did not contain a typical signal sequence cleavage site. No significant homology was detected when the DNA sequence of the nsr gene and the amino acid sequence of its putative product were compared with other available sequences. When subjected to Southern hybridization, a 1.2-kb DraI fragment encoding the nsr gene did not hybridize with the genomic DNA of the nisin-producing strain L. lactis subsp. lactis 11454. Images PMID:1903915

Froseth, B R; McKay, L L

1991-01-01

424

DrsG from Streptococcus dysgalactiae subsp. equisimilis Inhibits the Antimicrobial Peptide LL-37  

PubMed Central

SIC and DRS are related proteins present in only 4 of the >200 Streptococcus pyogenes emm types. These proteins inhibit complement-mediated lysis and/or the activity of certain antimicrobial peptides (AMPs). A gene encoding a homologue of these proteins, herein called DrsG, has been identified in the related bacterium Streptococcus dysgalactiae subsp. equisimilis. Here we show that geographically dispersed isolates representing 14 of 50 emm types examined possess variants of drsG. However, not all isolates within the drsG-positive emm types possess the gene. Sequence comparisons also revealed a high degree of conservation in different S. dysgalactiae subsp. equisimilis emm types. To examine the biological activity of DrsG, recombinant versions of two major DrsG variants, DrsGS and DrsGL, were expressed and purified. Western blot analysis using antisera raised to these proteins demonstrated both variants to be expressed and secreted into culture supernatants. Unlike SIC, but similar to DRS, DrsG does not inhibit complement-mediated lysis. However, like both SIC and DRS, DrsG is a ligand of the cathelicidin LL-37 and is inhibitory to its bactericidal activity in in vitro assays. Conservation of prolines in the C-terminal region also suggests that these residues are important in the biology of this family of proteins. This is the first report demonstrating the activity of an AMP-inhibitory protein in S. dysgalactiae subsp. equisimilis and suggests that inhibition of AMP activity is the primary function of this family of proteins. The acquisition of the complement-inhibitory activity of SIC may reflect its continuing evolution. PMID:24664506

Smyth, Danielle; Cameron, Ainslie; Davies, Mark R.; McNeilly, Celia; Hafner, Louise; Sriprakash, Kadaba S.

2014-01-01

425

Phenolic content and antioxidant property of the bark extracts of Ziziphus mucronata Willd. subsp. mucronata Willd  

PubMed Central

Background Several plants traditionally used in treatment of a variety of infections in South Africa are reported in ethnobotanical surveys. Many of these plants including Ziziphus mucronata subsp. mucronata lack scientific reports to support their medicinal importance. Methods The antioxidant activities and phenolic contents of the acetone, ethanol and aqueous extracts of the stems of Z. mucronata subsp. mucronata were evaluated using in vitro standard methods. The total phenol, total flavonoids and proanthocyanidin content were determined spectrophotometrically. Quercetin, Tannic acid and catechin equivalents were used for these parameters. The antioxidant activities of the stem bark extracts of this plant were determined by ABTS, DPPH, and ferrous reducing antioxidant property (FRAP) methods. Results The quantity of the phenolic compounds, flavonoids and proanthocyanidins detected differ significantly in the various extracts. The phenolics were significantly higher than the flavonoids and proanthocyanidin contents in all the extracts investigated. The ferric reducing ability and the radical scavenging activities of the extracts were very high and dose-dependent. The ethanol extract had the highest antioxidant activity, followed by the acetone extract while the aqueous extract was the least active. Reacting with ABTS, the 50% inhibitory concentrations (IC50) were (0.0429 ± 0.04 mg/ml) for aqueous, (0.0317 ± 0.04 mg/ml) for acetone and (0.0306 ± 0.04 mg/ml) for ethanol extracts while they inhibited DPPH radical with 50% inhibitory concentration (IC50) values of 0.0646 ± 0.02 mg/ml (aqueous), 0.0482 ± 0.02 mg/ml (acetone) and 0.0422 ± 0.03 mg/ml (ethanol). Conclusions A correlation between the antioxidant activity and the total phenolic contents of the extracts indicated that phenolic compounds were the dominant contributors to the antioxidant activity of the plant. This study, therefore, demonstrated that Z. mucronata subsp. mucronata has strong antioxidant property and free radical scavenging capability. PMID:22176659

2011-01-01

426

First Report of Cowpea Mild Mottle Carlavirus on Yardlong Bean (Vigna unguiculata subsp. sesquipedalis) in Venezuela  

PubMed Central

Yardlong bean (Vigna unguiculata subsp. sesquipedalis) plants with virus-like systemic mottling and leaf distortion were observed in both experimental and commercial fields in Aragua State, Venezuela. Symptomatic leaves were shown to contain carlavirus-like particles. RT-PCR analysis with carlavirus-specific primers was positive in all tested samples. Nucleotide sequences of the obtained amplicons showed 84%–74% similarity to corresponding sequences of Cowpea mild mottle virus (CPMMV) isolates deposited in the GenBank database. This is the first report of CPMMV in Venezuela and is thought to be the first report of CPMMV infecting yardlong bean. PMID:23242372

Brito, Miriam; Fernández-Rodríguez, Thaly; Garrido, Mario José; Mejías, Alexander; Romano, Mirtha; Marys, Edgloris

2012-01-01

427

High phylogenetic proximity of isolates of Mycobacterium avium subsp. hominissuis over a two decades-period.  

PubMed

The genetic diversity of 47 human isolates of Mycobacterium avium subsp. hominissuis (MAH) was determined by MIRU-VNTR genotyping. Sixteen unique VNTR patterns and eight clusters including a total 39 isolates were detected; six clusters included strains isolated during at least a 15-year period. Minimum spanning tree analysis showed that 14 VNTR patterns, occurring either as clustered or unique isolates, differed from the nearest one for one allelic variation and that the remaining two patterns differed for two allelic variations. The high phylogenetic proximity of the isolates, even over a long time period, indicates that the MAH genotype is highly homogeneous and conserved. PMID:23416257

Rindi, Laura; Buzzigoli, Andrea; Medici, Chiara; Garzelli, Carlo

2013-06-01

428

Phenolic Glycosides with antiproteasomal activity from Centaurea urvillei DC. subsp. urvillei  

Microsoft Academic Search

A new flavanone glycoside, naringenin-7-O-?-d-glucuronopyranoside, and a new flavonol glycoside, 6-hydroxykaempferol-7-O-?-d-glucuronopyranoside were isolated together with 12 known compounds, 5 flavone glycoside; hispidulin-7-O-?-d-glucuronopyranoside, apigenin-7-O-?-d-methylglucuronopyranoside, hispidulin-7-O-?-d-methylglucuronopyranoside, hispidulin-7-O-?-d-glucopyranoside, apigenin-7-O-?-d-glucopyranoside, a flavonol; kaempferol, two flavone; apigenin, and luteolin, a flavanone glycoside; eriodictyol-7-O-?-d-glucuronopyranoside, and three phenol glycoside; arbutin, salidroside, and 3,5-dihydroxyphenethyl alcohol-3-O-?-d-glucopyranoside from Centaurea urvillei subsp. urvillei. The structure elucidation of the new compounds was

Derya Gülcemal; Özgen Alanku?-Çal??kan; Canan Karaalp; Ahmet Uygar Örs; Petek Ballar; Erdal Bedir

2010-01-01

429

First report of Cowpea mild mottle Carlavirus on yardlong bean (Vigna unguiculata subsp. sesquipedalis) in Venezuela.  

PubMed

Yardlong bean (Vigna unguiculata subsp. sesquipedalis) plants with virus-like systemic mottling and leaf distortion were observed in both experimental and commercial fields in Aragua State, Venezuela. Symptomatic leaves were shown to contain carlavirus-like particles. RT-PCR analysis with carlavirus-specific primers was positive in all tested samples. Nucleotide sequences of the obtained amplicons showed 84%-74% similarity to corresponding sequences of Cowpea mild mottle virus (CPMMV) isolates deposited in the GenBank database. This is the first report of CPMMV in Venezuela and is thought to be the first report of CPMMV infecting yardlong bean. PMID:23242372

Brito, Miriam; Fernández-Rodríguez, Thaly; Garrido, Mario José; Mejías, Alexander; Romano, Mirtha; Marys, Edgloris

2012-12-01

430

Salmonella enterica subsp. arizonae bone and joints sepsis. A case report and literature review.  

PubMed

Osteoarticular infections caused by Salmonella enterica subsp. arizonae are rarely seen in humans but young children and immunocompromised adults are at particular risk of acquiring this bacteria. Reptiles and their by-products (e.g. meat preparations or medications) are particularly likely to harbor Salmonella. We report on a case of septic arthritis of the hip transmitted by a reptile in a 10-month-old child. We carry out a recall of the complex nomenclature of Salmonella, a review of the literature and provide information on the recommended precautions for reducing the risk of transmission of Salmonella from reptiles to humans. PMID:19395336

Schneider, L; Ehlinger, M; Stanchina, C; Giacomelli, M-C; Gicquel, P; Karger, C; Clavert, J-M

2009-05-01

431

Genetic IS901 RFLP diversity among Mycobacterium avium subsp. avium isolates from four pheasant flocks.  

PubMed

IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four pheasant farms was performed. Using this method, six different IS901 RFLP types (E, F, G, M, Q, and V) were identified. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles observed in the present study indicate MAA transmission between pheasants and goshawks in the same locality. In two flocks, different pheasants within a flock as well as in various organs of five individual pheasants were found to have two distinct IS901 RFLP profiles. PMID:23388436

Moravkova, Monika; Lamka, Jiri; Slany, Michal; Pavlik, Ivo

2013-01-01

432

Genetic IS901 RFLP diversity among Mycobacterium avium subsp. avium isolates from four pheasant flocks  

PubMed Central

IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four pheasant farms was performed. Using this method, six different IS901 RFLP types (E, F, G, M, Q, and V) were identified. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles observed in the present study indicate MAA transmission between pheasants and goshawks in the same locality. In two flocks, different pheasants within a flock as well as in various organs of five individual pheasants were found to have two distinct IS901 RFLP profiles. PMID:23388436

Moravkova, Monika; Lamka, Jiri; Slany, Michal

2013-01-01

433

Structure of a zwitterionic O-polysaccharide from Photorhabdus temperata subsp. cinerea 3240.  

PubMed

A phosphorylated O-polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Photorhabdus temperata subsp. cinerea 3240 and studied by sugar analysis, dephosphorylation, and (1)H and (13)C NMR spectroscopy. The following structure of the linear trisaccharide repeating unit of the O-polysaccharide was established: ?3)-?-d-GalpNAc4PEtN-(1?4)-?-d-GlcpA-(1?3)-?-d-FucpNAc4N-(1? where GlcA indicates glucuronic acid, FucNAc4N 2-acetamido-4-amino-2,4,6-trideoxygalactose, and PEtN 2-aminoethyl phosphate. PMID:25699972

Kondakova, Anna N; Kirsheva, Nadezhda A; Arbatsky, Nikolay P; Shaikhutdinova, Rima Z; Shashkov, Alexander S; Ivanov, Sergey A; Anisimov, Andrey P; Knirel, Yuriy A

2015-04-30

434

Chemical Composition and Seasonal Variation of Hypericum hircinum L. subsp. majus (Aiton) N. Robson Essential Oil  

Microsoft Academic Search

Essential oils obtained by hydrodistillation of leaves (LV), flowers (FL) and fruits (FR) of Hypericum hircinum subsp. majus from Marche (Italy), were analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography\\/mass spectrometry (GC\\/MS). Ninety-two volatile components were identified in the oils, representing 81.41–94.36% of the total oils. The major compounds were cis-?-guaiene (23.25–41.23%) and ?-selinene (8.48–25.20%) in LV, ?-selinene

F. Maggi; B. Tirillini; S. Vittori; G. Sagratini; F. Papa

2010-01-01

435

Complete genome sequence of the ethanol-producing Zymomonas mobilis subsp. mobilis centrotype ATCC 29191.  

PubMed

Zymomonas mobilis is an ethanologenic bacterium that has been studied for use in biofuel production. Of the sequenced Zymomonas strains, ATCC 29191 has been described as the phenotypic centrotype of Zymomonas mobilis subsp. mobilis, the taxon that harbors the highest ethanol-producing Z. mobilis strains. ATCC 29191 was isolated in Kinshasa, Congo, from palm wine fermentations. This strain is reported to be a robust levan producer, while in recent years it has been employed in studies addressing Z. mobilis respiration. Here we announce the finishing and annotation of the ATCC 29191 genome, which comprises one chromosome and three plasmids. PMID:23045486

Desiniotis, Andreas; Kouvelis, Vassili N; Davenport, Karen; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A; Woyke, Tanja; Kyrpides, Nikos C; Typas, Milton A; Pappas, Katherine M

2012-11-01

436

High-Throughput Direct Fecal PCR Assay for Detection of Mycobacterium avium subsp. paratuberculosis in Sheep and Cattle  

PubMed Central

Johne's disease (JD) is a chronic enteric disease caused by Mycobacterium avium subsp. paratuberculosis that affects ruminants. Transmission occurs by the fecal-oral route. A commonly used antemortem diagnostic test for the detection of M. avium subsp. paratuberculosis in feces is liquid culture; however, a major constraint is the 2- to 3-month incubation period needed for this method. Rapid methods for the detection of M. avium subsp. paratuberculosis based on PCR have been reported, but comprehensive validation data are lacking. We describe here a new test, the high-throughput-Johnes (HT-J), to detect M. avium subsp. paratuberculosis in feces. Its diagnostic accuracy was compared with that of liquid radiometric (Bactec) fecal culture using samples from cattle (1,330 samples from 23 herds) and sheep (596 samples from 16 flocks). The multistage protocol involves the recovery of M. avium subsp. paratuberculosis cells from a fecal suspension, cell rupture by bead beating, extraction of DNA using magnetic beads, and IS900 quantitative PCR. The limit of detection of the assay was 0.0005 pg, and the limit of quantification was 0.005 pg M. avium subsp. paratuberculosis genomic DNA. Only M. avium subsp. paratuberculosis was detected from a panel of 51 mycobacterial isolates, including 10 with IS900-like sequences. Of the 549 culture-negative fecal samples from unexposed herds and flocks, 99% were negative in the HT-J test, while 60% of the bovine- and 84% of the ovine-culture-positive samples were positive in the HT-J test. As similar total numbers of samples from M. avium subsp. paratuberculosis-exposed animals were positive in culture and HT-J tests in both species, and as the results of a McNemar's test were not significant, these methods probably have similar sensitivities, but the true diagnostic sensitivities of these tests are unknown. These validation data meet the consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis and the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines (S. A. Bustin et al., Clin. Chem. 55:611–622, 2009, doi:10.1373/clinchem.2008.112797). The HT-J assay has been approved for use in JD control programs in Australia and New Zealand. PMID:24352996

Waldron, Anna M.; Galea, Francesca; Whittington, Ann-Michele; Saunders, Vanessa F.; Begg, Douglas J.; de Silva, Kumudika; Purdie, Auriol C.; Whittington, Richard J.

2014-01-01

437

Genomic deletion marking an emerging subclone of Francisella tularensis subsp. holarctica in France and the Iberian Peninsula.  

PubMed

Francisella tularensis subsp. holarctica is widely disseminated in North America and the boreal and temperate regions of the Eurasian continent. Comparative genomic analyses identified a 1.59-kb genomic deletion specific to F. tularensis subsp. holarctica isolates from Spain and France. Phylogenetic analysis of strains carrying this deletion by multiple-locus variable-number tandem repeat analysis showed that the strains comprise a highly related set of genotypes, implying that these strains were recently introduced or recently emerged by clonal expansion in France and the Iberian Peninsula. PMID:17890329

Dempsey, M P; Dobson, M; Zhang, C; Zhang, M; Lion, C; Gutiérrez-Martín, C B; Iwen, P C; Fey, P D; Olson, M E; Niemeyer, D; Francesconi, S; Crawford, R; Stanley, M; Rhodes, J; Wagner, D M; Vogler, A J; Birdsell, D; Keim, P; Johansson, A; Hinrichs, S H; Benson, A K

2007-11-01

438

Genomic Deletion Marking an Emerging Subclone of Francisella tularensis subsp. holarctica in France and the Iberian Peninsula? †  

PubMed Central

Francisella tularensis subsp. holarctica is widely disseminated in North America and the boreal and temperate regions of the Eurasian continent. Comparative genomic analyses identified a 1.59-kb genomic deletion specific to F. tularensis subsp. holarctica isolates from Spain and France. Phylogenetic analysis of strains carrying this deletion by multiple-locus variable-number tandem repeat analysis showed that the strains comprise a highly related set of genotypes, implying that these strains were recently introduced or recently emerged by clonal expansion in France and the Iberian Peninsula. PMID:17890329

Dempsey, M. P.; Dobson, M.; Zhang, C.; Zhang, M.; Lion, C.; Gutiérrez-Martín, C. B.; Iwen, P. C.; Fey, P. D.; Olson, M. E.; Niemeyer, D.; Francesconi, S.; Crawford, R.; Stanley, M.; Rhodes, J.; Wagner, D. M.; Vogler, A. J.; Birdsell, D.; Keim, P.; Johansson, A.; Hinrichs, S. H.; Benson, A. K.

2007-01-01

439

O3 flux-related responsiveness of photosynthesis, respiration, and stomatal conductance of adult Fagus sylvatica to experimentally enhanced free-air O3 exposure.  

PubMed

Knowledge of responses of photosynthesis, respiration, and stomatal conductance to cumulative ozone uptake (COU) is still scarce, and this is particularly the case for adult trees. The effect of ozone (O(3)) exposure on trees was examined with 60-year-old beech trees (FAGUS SYLVATICA) at a forest site of southern Germany. Trees were exposed to the ambient O(3) regime (1 x O(3)) or an experimentally elevated twice-ambient O(3) regime (2 x O(3)). The elevated 2 x O (3) regime was provided by means of a free-air O(3) canopy exposure system. The hypotheses were tested that (1) gas exchange is negatively affected by O(3) and (2) the effects of O(3) are dose-dependent and thus the sizes of differences between treatments are positively related to COU. Gas exchange (light-saturated CO(2) uptake rate A(max), stomatal conductance g (s), maximum rate of carboxylation Vc (max), ribulose-1,5-bisphosphate turnover limited rate of photosynthesis J (max), CO(2) compensation point CP, apparent quantum yield of net CO(2) uptake AQ, carboxylation efficiency CE, day- and nighttime respiration) and chlorophyll fluorescence (electron transfer rate, ETR) were measured IN SITU on attached sun and shade leaves. Measurements were made periodically throughout the growing seasons of 2003 (an exceptionally dry year) and 2004 (a year with average rainfall). In 2004 Vc(max), J(max), and CE were lower in trees receiving 2 x O(3) compared with the ambient O(3) regime (1 x O(3)). Treatment differences in Vc (max), J (max), CE were rather small in 2004 (i.e., parameter levels were lower by 10 - 30 % in 2 x O(3) than 1 x O(3)) and not significant in 2003. In 2004 COU was positively correlated with the difference between treatments in A (max), g (s), and ETR (i.e., consistent with the dose-dependence of O(3)'s deleterious effects). However, in 2003, differences in A(max), g (s), and ETR between the two O(3) regimes were smaller at the end of the dry summer 2003 (i.e., when COU was greatest). The relationship of COU with effects on gas exchange can apparently be complex and, in fact, varied between years and within the growing season. In addition, high doses of O(3) did not always have significant effects on leaf gas exchange. In view of the key findings, both hypotheses were to be rejected. PMID:17357014

Löw, M; Häberle, K-H; Warren, C R; Matyssek, R

2007-03-01

440

Co-occurrence patterns of trees along macro-climatic gradients and their potential influence on the present and future distribution of Fagus sylvatica L.  

USGS Publications Warehouse

Aim During recent and future climate change, shifts in large-scale species ranges are expected due to the hypothesized major role of climatic factors in regulating species distributions. The stress-gradient hypothesis suggests that biotic interactions may act as major constraints on species distributions under more favourable growing conditions, while climatic constraints may dominate under unfavourable conditions. We tested this hypothesis for one focal tree species having three major competitors using broad-scale environmental data. We evaluated the variation of species co-occurrence patterns in climate space and estimated the influence of these patterns on the distribution of the focal species for current and projected future climates.Location Europe.Methods We used ICP Forest Level 1 data as well as climatic, topographic and edaphic variables. First, correlations between the relative abundance of European beech (Fagus sylvatica) and three major competitor species (Picea abies, Pinus sylvestris and Quercus robur) were analysed in environmental space, and then projected to geographic space. Second, a sensitivity analysis was performed using generalized additive models (GAM) to evaluate where and how much the predicted F. sylvatica distribution varied under current and future climates if potential competitor species were included or excluded. We evaluated if these areas coincide with current species co-occurrence patterns.Results Correlation analyses supported the stress-gradient hypothesis: towards favourable growing conditions of F. sylvatica, its abundance was strongly linked to the abundance of its competitors, while this link weakened towards unfavourable growing conditions, with stronger correlations in the south and at low elevations than in the north and at high elevations. The sensitivity analysis showed a potential spatial segregation of species with changing climate and a pronounced shift of zones where co-occurrence patterns may play a major role.Main conclusions Our results demonstrate the importance of species co-occurrence patterns for calibrating improved species distribution models for use in projections of climate effects. The correlation approach is able to localize European areas where inclusion of biotic predictors is effective. The climate-induced spatial segregation of the major tree species could have ecological and economic consequences. ?? 2010 Blackwell Publishing Ltd.

Meier, E.S.; Edwards, T.C., Jr.; Kienast, Felix; Dobbertin, M.; Zimmermann, N.E.

2011-01-01

441

Biochemical and genetic evidence for the transfer of Mycobacterium tuberculosis subsp. caprae Aranaz et al. 1999 to the species Mycobacterium bovis Karlson and Lessel 1970 (approved lists 1980) as Mycobacterium bovis subsp. caprae comb. nov.  

PubMed

We propose to replace the species designation Mycobacterium tuberculosis subsp. caprae (Aranaz et al. 1999) by Mycobacterium bovis subsp. caprae comb. nov., since isolates of this subspecies share their main growth, biochemical and genetic characteristics with M. bovis and not with M. tuberculosis. These include negative biochemical test results for niacin accumulation and nitrate reduction as well as genetic features like the presence of an M. bovis-specific mutation in the oxyR locus, absence of the mtp40 sequence and a specific mutation in the gyrB gene, all of which have been described as characteristics for the differentiation of M. bovis. The only obvious biochemical character that differentiates the caprae subtype from other M. bovis isolates is susceptibility to pyrazinamide (PZA), which is due to the lack of a single point mutation in the pncA gene. However, susceptibility to PZA among clinical isolates of M. bovis isolates has been reported previously and, thus, may now been explained by a PZA-susceptible subspecies of M. bovis. We conclude that the species designation M. tuberculosis subsp. caprae is misleading and not correct in light of the biochemical and genetic characteristics and propose that the accurate designation of isolates of this subtype is M. bovis subsp. caprae. PMID:11931153

Niemann, Stefan; Richter, Elvira; Rüsch-Gerdes, Sabine

2002-03-01

442

Volatiles fingerprint of Artemisia umbelliformis subsp. eriantha by headspace-solid phase microextraction GC-MS.  

PubMed

Artemisia umbelliformis subsp. eriantha is a protected species, whose essential oil is used in liqueur industry. Volatile profiles of fresh leaves and flowers from wild plants in comparison with regenerated in vitro plants introduced in experimental fields within an Italian national park were evaluated by headspace-solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS). The chromatographic profiles appear to be qualitatively similar. The content of thujones, the characteristic metabolites of this species, is comparable with that obtained by analysis of essential oils. Principal component analysis of the HS-SPME-GC-MS data supports the possibility of differentiating scent blends of genetically identical plants, and even flowers and leaves from the same individual. HS-SPME-GC-MS is shown to be a very efficient method to analyse and to describe the pattern of components of A. umbelliformis subsp. eriantha cultivars' scents. It represents a rapid screening method highly recommended for the study of protected species, because it is non-destructive and it only requires small amounts of fresh material. PMID:23962361

Reale, Samantha; Pace, Loretta; D'Archivio, Angelo Antonio; De Angelis, Francesco; Marcozzi, Giordana

2014-01-01

443

A Metabolic Enzyme as a Primary Virulence Factor of Mycoplasma mycoides subsp. mycoides Small Colony  

PubMed Central

During evolution, pathogenic bacteria have developed complex interactions with their hosts. This has frequently involved the acquisition of virulence factors on pathogenicity islands, plasmids, transposons, or prophages, allowing them to colonize, survive, and replicate within the host. In contrast, Mycoplasma species, the smallest self-replicating organisms, have regressively evolved from gram-positive bacteria by reduction of the genome to a minimal size, with the consequence that they have economized their genetic resources. Hence, pathogenic Mycoplasma species lack typical primary virulence factors such as toxins, cytolysins, and invasins. Consequently, little is known how pathogenic Mycoplasma species cause host cell damage, inflammation, and disease. Here we identify a novel primary virulence determinant in Mycoplasma mycoides subsp. mycoides Small Colony (SC), which causes host cell injury. This virulence factor, released in significant amounts in the presence of glycerol in the growth medium, consists of toxic by-products such as H2O2 formed by l-?-glycerophosphate oxidase (GlpO), a membrane-located enzyme