bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional Analysis of GlnE, an Essential Adenylyl Transferase in
Mycobacterium tuberculosis
Authors: Carroll Paul , Pashley Carey A. , Parish Tanya
Published: May 2008

Glutamine synthetase (GS) plays an important role in nitrogen assimilation. The major GS of
Mycobacterium tuberculosis
is GlnA1, a type I GS whose activity is controlled by posttranscriptional modification by GlnE. GlnE is an adenylyl transferase comprised of an adenylylating domain and a deadenylylating domain which modulate GS activity. We previously demonstrated that GlnE is essential in
M. tuberculosis
in normal growth medium. In this study, we further show that GlnE is required under multiple medium conditions, including in nitrogen-limited medium. We demonstrate that adenylylation is the critical activity for
M. tuberculosis
survival, since we were able to delete the deadenylylation domain with no apparent effect on growth or GS activity. Furthermore, we identified a critical aspartate residue in the proposed nucleotidyltransferase motif. Temperature-sensitive mutants of GlnE were generated and shown to have a defect in growth and GS activity in nitrogen-limited medium. Finally, we were able to generate a GlnE null mutant in the presence of
l
-methionine sulfoximine, a GS inhibitor, and glutamine supplementation. In the presence of these supplements, the null mutant was able to grow similarly to the wild type. Surprisingly, the GlnE mutant was able to survive and grow for extended periods in liquid medium, but not on solid medium, in the absence of GS inhibition. Thus, we have confirmed that the unusual requirement of
M. tuberculosis
for GlnE adenylylation activity is linked to the activity of GS in the cell.
The Putative Hybrid Sensor Kinase SypF Coordinates Biofilm Formation inVibrio fischeriby Acting Upstream of Two Response Regulators, SypG and VpsR
Authors: Darnell Cynthia L. , Hussa Elizabeth A. , Visick Karen L.
Published: May 2008

Colonization of the Hawaiian squidEuprymna scolopesby the marine bacteriumVibrio fischerirequires the symbiosis polysaccharide (syp) gene cluster, which contributes to symbiotic initiation by promoting biofilm formation on the surface of the symbiotic organ. We previously described roles for thesyp-encoded response regulator SypG and an unlinked gene encoding the sensor kinase RscS in controllingsyptranscription and inducingsyp-dependent cell-cell aggregation phenotypes. Here, we report the involvement of an additionalsyp-encoded regulator, the putative sensor kinase SypF, in promoting biofilm formation. Through the isolation of an increased activity allele,sypF1, we determined that SypF can function to inducesyptranscription as well as a variety of biofilm phenotypes, including wrinkled colony formation, adherence to glass, and pellicle formation. SypF1-mediated transcription of thesypcluster was entirely dependent on SypG. However, the biofilm phenotypes were reduced, not eliminated, in thesypGmutant. These phenotypes were also reduced in a mutant deleted forsypE, anothersyp-encoded response regulator. However, SypF1 still induced phenotypes in asypG sypEdouble mutant, suggesting that SypF1 might activate another regulator(s). Our subsequent work revealed that the residual SypF1-induced biofilm formation depended on VpsR, a putative response regulator, and cellulose biosynthesis. These data support a model in which a network of regulators and at least two polysaccharide loci contribute to biofilm formation inV. fischeri.
Characterization of
Clostridium perfringens
Spores That Lack SpoVA Proteins and Dipicolinic Acid
Authors: Paredes-Sabja Daniel , Setlow Barbara , Setlow Peter , Sarker Mahfuzur R.
Published: May 2008

Spores of
Clostridium perfringens
possess high heat resistance, and when these spores germinate and return to active growth, they can cause gastrointestinal disease. Work with
Bacillus subtilis
has shown that the spore's dipicolinic acid (DPA) level can markedly influence both spore germination and resistance and that the proteins encoded by the
spoVA
operon are essential for DPA uptake by the developing spore during sporulation. We now find that proteins encoded by the
spoVA
operon are also essential for the uptake of Ca
2+
and DPA into the developing spore during
C. perfringens
sporulation. Spores of a
spoVA
mutant had little, if any, Ca
2+
and DPA, and their core water content was approximately twofold higher than that of wild-type spores. These DPA-less spores did not germinate spontaneously, as DPA-less
B. subtilis
spores do. Indeed, wild-type and
spoVA C. perfringens
spores germinated similarly with a mixture of
l
-asparagine and KCl (AK), KCl alone, or a 1:1 chelate of Ca
2+
and DPA (Ca-DPA). However, the viability of
C. perfringens spoVA
spores was 20-fold lower than the viability of wild-type spores. Decoated wild-type and
spoVA
spores exhibited little, if any, germination with AK, KCl, or exogenous Ca-DPA, and their colony-forming efficiency was 10
3
- to 10
4
-fold lower than that of intact spores. However, lysozyme treatment rescued these decoated spores. Although the levels of DNA-protective α/β-type, small, acid-soluble spore proteins in
spoVA
spores were similar to those in wild-type spores,
spoVA
spores exhibited markedly lower resistance to moist heat, formaldehyde, HCl, hydrogen peroxide, nitrous acid, and UV radiation than wild-type spores did. In sum, these results suggest the following. (i) SpoVA proteins are essential for Ca-DPA uptake by developing spores during
C. perfringens
sporulation. (ii) SpoVA proteins and Ca-DPA release are not required for
C. perfringens
spore germination. (iii) A low spore core water content is essential for full resistance of
C. perfringens
spores to moist heat, UV radiation, and chemicals.
Clusters of Charged Residues at the C Terminus of MotA and N Terminus of MotB Are Important for Function of the
Escherichia coli
Flagellar Motor
Authors: Hosking Edan R. , Manson Michael D.
Published: May 2008

MotA contains a conserved C-terminal cluster of negatively charged residues, and MotB contains a conserved N-terminal cluster of positively charged residues. Charge-altering mutations affecting these residues impair motility but do not diminish Mot protein levels. The motility defects are reversed by second-site mutations targeting the same or partner protein.
CpcM Posttranslationally Methylates Asparagine-71/72 of Phycobiliprotein Beta Subunits in
Synechococcus
sp. Strain PCC 7002 and
Synechocystis
sp. Strain PCC 6803
Authors: Shen Gaozhong , Leonard Heidi S. , Schluchter Wendy M. , Bryant Donald A.
Published: May 2008

Cyanobacteria produce phycobilisomes, which are macromolecular light-harvesting complexes mostly assembled from phycobiliproteins. Phycobiliprotein beta subunits contain a highly conserved γ-
N
-methylasparagine residue, which results from the posttranslational modification of Asn71/72. Through comparative genomic analyses, we identified a gene, denoted
cpcM
, that (i) encodes a protein with sequence similarity to other
S
-adenosylmethionine-dependent methyltransferases, (ii) is found in all sequenced cyanobacterial genomes, and (iii) often occurs near genes encoding phycobiliproteins in cyanobacterial genomes. The
cpcM
genes of
Synechococcus
sp. strain PCC 7002 and
Synechocystis
sp. strain PCC 6803 were insertionally inactivated. Mass spectrometric analyses of phycobiliproteins isolated from the mutants confirmed that the CpcB, ApcB, and ApcF were 14 Da lighter than their wild-type counterparts. Trypsin digestion and mass analyses of phycobiliproteins isolated from the mutants showed that tryptic peptides from phycocyanin that included Asn72 were also 14 Da lighter than the equivalent peptides from wild-type strains. Thus, CpcM is the methyltransferase that modifies the amide nitrogen of Asn71/72 of CpcB, ApcB, and ApcF. When cells were grown at low light intensity, the
cpcM
mutants were phenotypically similar to the wild-type strains. However, the mutants were sensitive to high-light stress, and the
cpcM
mutant of
Synechocystis
sp. strain PCC 6803 was unable to grow at moderately high light intensities. Fluorescence emission measurements showed that the ability to perform state transitions was impaired in the
cpcM
mutants and suggested that energy transfer from phycobiliproteins to the photosystems was also less efficient. The possible functions of asparagine N methylation of phycobiliproteins are discussed.
Substrate Specificity of the 3-Methylcrotonyl Coenzyme A (CoA) and Geranyl-CoA Carboxylases from
Pseudomonas aeruginosa
Authors: Aguilar J. A. , Díaz-Pérez C. , Díaz-Pérez A. L. , Rodríguez-Zavala J. S. , Nikolau B. J. , Campos-García J.
Published: May 2008

Biotin-containing 3-methylcrotonyl coenzyme A (MC-CoA) carboxylase (MCCase) and geranyl-CoA (G-CoA) carboxylase (GCCase) from
Pseudomonas aeruginosa
were expressed as His-tagged recombinant proteins in
Escherichia coli
. Both native and recombinant MCCase and GCCase showed pH and temperature optima of 8.5 and 37°C. The apparent
K
0.5
(affinity constant for non-Michaelis-Menten kinetics behavior) values of MCCase for MC-CoA, ATP, and bicarbonate were 9.8 μM, 13 μM, and 0.8 μM, respectively. MCCase activity showed sigmoidal kinetics for all the substrates and did not carboxylate G-CoA. In contrast, GCCase catalyzed the carboxylation of both G-CoA and MC-CoA. GCCase also showed sigmoidal kinetic behavior for G-CoA and bicarbonate but showed Michaelis-Menten kinetics for MC-CoA and the cosubstrate ATP. The apparent
K
0.5
values of GCCase were 8.8 μM and 1.2 μM for G-CoA and bicarbonate, respectively, and the apparent

K
m

values of GCCase were 10 μM for ATP and 14 μM for MC-CoA. The catalytic efficiencies of GCCase for G-CoA and MC-CoA were 56 and 22, respectively, indicating that G-CoA is preferred over MC-CoA as a substrate. The enzymatic properties of GCCase suggest that it may substitute for MCCase in leucine catabolism and that both the MCCase and GCCase enzymes play important roles in the leucine and acyclic terpene catabolic pathways.
Role of Dipicolinic Acid in the Germination, Stability, and Viability of Spores of
Bacillus subtilis
Authors: Magge Anil , Granger Amanda C. , Wahome Paul G. , Setlow Barbara , Vepachedu Venkata R. , Loshon Charles A. , Peng Lixin , Chen De , Li Yong-qing , Setlow Peter
Published: May 2008

Spores of
Bacillus subtilis spoVF
strains that cannot synthesize dipicolinic acid (DPA) but take it up during sporulation were prepared in medium with various DPA concentrations, and the germination and viability of these spores as well as the DPA content in individual spores were measured. Levels of some other small molecules in DPA-less spores were also measured. These studies have allowed the following conclusions. (i) Spores with no DPA or low DPA levels that lack either the cortex-lytic enzyme (CLE) SleB or the receptors that respond to nutrient germinants could be isolated but were unstable and spontaneously initiated early steps in spore germination. (ii) Spores that lacked SleB and nutrient germinant receptors and also had low DPA levels were more stable. (iii) Spontaneous germination of spores with no DPA or low DPA levels was at least in part via activation of SleB. (iv) The other redundant CLE, CwlJ, was activated only by the release of high levels of DPA from spores. (v) Low levels of DPA were sufficient for the viability of spores that lacked most α/β-type small, acid-soluble spore proteins. (vi) DPA levels accumulated in spores prepared in low-DPA-containing media varied greatly between individual spores, in contrast to the presence of more homogeneous DPA levels in individual spores made in media with high DPA concentrations. (vii) At least the great majority of spores of several
spoVF
strains that contained no DPA also lacked other major spore small molecules and had gone through some of the early reactions in spore germination.
Lactobacillus reuteri
DSM 20016 Produces Cobalamin-Dependent Diol Dehydratase in Metabolosomes and Metabolizes 1,2-Propanediol by Disproportionation
Authors: Sriramulu Dinesh Diraviam , Liang Mingzhi , Hernandez-Romero Diana , Raux-Deery Evelyne , Lünsdorf Heinrich , Parsons Joshua B. , Warren Martin J. , Prentice Michael B.
Published: May 2008

A
Lactobacillus reuteri
strain isolated from sourdough is known to produce the vitamin cobalamin. The organism requires this for glycerol cofermentation by a cobalamin-dependent enzyme, usually termed glycerol dehydratase, in the synthesis of the antimicrobial substance reuterin. We show that the cobalamin-synthesizing capacity of another
L. reuteri
strain (20016, the type strain, isolated from the human gut and recently sequenced as F275) is genetically and phenotypically linked, as in the
Enterobacteriaceae
, to the production of a cobalamin-dependent enzyme which is associated with a bacterial microcompartment (metabolosome) and known as diol dehydratase. We show that this enzyme allows
L. reuteri
to carry out a disproportionation reaction converting 1,2-propanediol to propionate and propanol. The wide distribution of this operon suggests that it is adapted to horizontal transmission between bacteria. However, there are significant genetic and phenotypic differences between the
Lactobacillus
background and the
Enterobacteriaceae
. Electron microscopy reveals that the bacterial microcompartment in
L. reuteri
occupies a smaller percentage of the cytoplasm than in gram-negative bacteria. DNA sequence data show evidence of a regulatory control mechanism different from that in gram-negative bacteria, with the presence of a catabolite-responsive element (CRE) sequence immediately upstream of the
pdu
operon encoding diol dehydratase and metabolosome structural genes in
L. reuteri
. The metabolosome-associated diol dehydratase we describe is the only candidate glycerol dehydratase present on inspection of the
L. reuteri
F275 genome sequence.
Endothelial nitric oxide synthase control mechanisms in the cutaneous vasculature of humans in vivo
Authors: Kellogg Dean L. , Zhao Joan L. , Wu Yubo
Published: May 2008

Nitric oxide (NO) participates in locally mediated vasodilation induced by increased local skin temperature (Tloc) and in sympathetically mediated vasodilation during whole body heat stress. We hypothesized that endothelial NOS (eNOS) participates in the former, but not the latter, response. We tested this hypothesis by examining the effects of the eNOS antagonist NG-amino-l-arginine (l-NAA) on skin blood flow (SkBF) responses to increased Tloc and whole body heat stress. Microdialysis probes were inserted into forearm skin for drug delivery. One microdialysis site was perfused with l-NAA in Ringer solution and a second site with Ringer solution alone. SkBF [laser-Doppler flowmetry (LDF)] and blood pressure [mean arterial pressure (MAP)] were monitored, and cutaneous vascular conductance (CVC) was calculated (CVC = LDF ÷ MAP). In protocol 1, Tloc was controlled with LDF/local heating units. Tloc initially was held at 34°C and then increased to 41.5°C. In protocol 2, after a normothermic period, whole body heat stress was induced (water-perfused suits). At the end of both protocols, 58 mM sodium nitroprusside was perfused at both microdialysis sites to cause maximal vasodilation for data normalization. In protocol 1, CVC at 34°C Tloc did not differ between l-NAA-treated and untreated sites ( P > 0.05). Local skin warming to 41.5°C Tloc increased CVC at both sites. This response was attenuated at l-NAA-treated sites ( P < 0.05). In protocol 2, during normothermia, CVC did not differ between l-NAA-treated and untreated sites ( P > 0.05). During heat stress, CVC rose to similar levels at l-NAA-treated and untreated sites ( P > 0.05). We conclude that eNOS is predominantly responsible for NO generation in skin during responses to increased Tloc, but not during reflex responses to whole body heat stress.
Catestatin (chromogranin A344-364) is a novel cardiosuppressive agent: inhibition of isoproterenol and endothelin signaling in the frog heart
Authors: Mazza Rosa , Gattuso Alfonsina , Mannarino Cinzia , Brar Bhawanjit K. , Barbieri Sandra Francesca , Tota Bruno , Mahata Sushil K.
Published: May 2008

The catecholamine release-inhibitory catestatin [Cts; human chromogranin (Cg) A352-372, bovine CgA344-364] is a vasoreactive and anti-hypertensive peptide derived from CgA. Using the isolated avascular frog heart as a bioassay, in which the interactions between the endocardial endothelium and the subjacent myocardium can be studied without the confounding effects of the vascular endothelium, we tested the direct cardiotropic effects of bovine Cts and its interaction with β-adrenergic (isoproterenol, ISO) and endothelin-1 (ET-1) signaling. Cts dose-dependently decreased stroke volume and stroke work, with a threshold concentration of 11 nM, approaching the in vivo level of the peptide. Cts reduced contractility by inhibiting phosphorylation of phospholamban (PLN). Furthermore, the Cts effect was abolished by pretreatment with either nitric oxide synthase ( NG-monomethyl-l-arginine) or guanylate cyclase (ODQ) inhibitors, or an ETBreceptor (ETBR) antagonist (BQ-788). Cts also noncompetitively inhibited the positive inotropic action of ISO. In addition, Cts inhibited the positive inotropic effect of ET-1, mediated by ETAreceptors, and did not alter the negative inotropic ET-1 influence mediated by ETBR. Cts action through ETBRwas further suggested when, in the presence of BQ-788, Cts failed to inhibit the positive inotropism of both ISO and ET-1 stimulation and PLN phosphorylation. We concluded that the cardiotropic actions of Cts, including the β-adrenergic and ET-1 antagonistic effects, support a novel role of this peptide as an autocrine-paracrine modulator of cardiac function, particularly when the stressed heart becomes a preferential target of both adrenergic and ET-1 stimuli.
Proteins interact with the cytosolic mineralocorticoid receptor depending on the ligand
Authors: Weber Miriam , Wehling Martin , Lösel Ralf
Published: May 2008

Steroid receptors belonging to the superfamily of nuclear receptors do not exist as single monomeric proteins but mediate their effects by the interaction with numerous other proteins, e.g., cofactors for transcription, but also other proteins involved in cellular signaling. This interaction may be ligand dependent, which explains the differential effects of receptor ligands. Whereas some receptors, e.g., the estrogen receptor, have been studied in great detail, much less is known about proteins interacting with the mineralocorticoid receptor (MR). In this study, we aimed to identify interacting proteins using a proteomics approach involving tagged receptor constructs. After affinity isolation of MR complexes, blue native electrophoresis revealed the presence of several populations of MR complexes differing in size and composition. During the identification of interacting proteins, various heat shock proteins but also several previously undescribed potential interactors were found, including 14-3-3-ε. We also demonstrate here that the cytosolic MR in the presence of detergent interacts in a ligand-selective manner with glucose-regulated protein 78 and propionyl-CoA carboxylase-β precursor, which are found in the unliganded or aldosterone-containing complex but not with spironolactone.
Different effects of palmitoyl-l-carnitine and palmitoyl-CoA on mitochondrial function in rat ventricular myocytes
Authors: Tominaga Hiromutsu , Katoh Hideki , Odagiri Keiichi , Takeuchi Yasuyo , Kawashima Hirotaka , Saotome Masao , Urushida Tsuyoshi , Satoh Hiroshi , Hayashi Hideharu
Published: May 2008

Although mitochondrial oxidative catabolism of fatty acid (FA) is a major energy source for the adult mammalian heart, cardiac lipotoxity resulting from elevated serum FA and enhanced FA use has been implicated in the pathogenesis of heart failure. To investigate the effects of intermediates of FA metabolism [palmitoyl-l-carnitine (Pal-car) and palmitoyl-CoA (Pal-CoA)] on mitochondrial function, we measured membrane potential (ΔΨm), opening of the mitochondrial permeability transition pore (mPTP), and the production of ROS in saponin-treated rat ventricular myocytes with a laser scanning confocal microscope. Our results revealed that 1) lower concentrations of Pal-car (1 and 5 μM) caused a slight hyperpolarization of ΔΨm[tetramethylrhodamine ethyl ester (TMRE) intensity increased to 115.5 ± 5.4% and 110.7 ± 1.6% of baseline, respectively, P < 0.05] but did not open the mPTP, 2) a higher concentration of Pal-car (10 μM) depolarized ΔΨm(TMRE intensity decreased to 61.9 ± 12.2% of baseline, P < 0.01) and opened the mPTP (calcein intensity decreased to 70.7 ± 2.8% of baseline, P < 0.01), 3) Pal-CoA depolarized ΔΨmwithout opening the mPTP, and 4) only the higher concentration of Pal-car (10 μM) increased ROS generation (2′,7′-dichlorofluorescein diacetate intensity increased to 3.4 ± 0.3-fold of baseline). We concluded that excessive exogenous intermediates of long-chain saturated FA may disturb mitochondrial function in different ways between Pal-car and Pal-CoA. The distinct mechanisms of the deteriorating effects of long-chain FA on mitochondrial function are important for our understanding of the development of cardiac diseases in systemic metabolic disorders.
Muscarinic receptor M1and phosphodiesterase 1 are key determinants in pulmonary vascular dysfunction following perinatal hypoxia in mice
Authors: Peyter Anne-Christine , Muehlethaler Vincent , Liaudet Lucas , Marino Mathieu , Di Bernardo Stefano , Diaceri Giacomo , Tolsa Jean-François
Published: May 2008

Perinatal adverse events such as limitation of nutrients or oxygen supply are associated with the occurrence of diseases in adulthood, like cardiovascular diseases and diabetes. We investigated the long-term effects of perinatal hypoxia on the lung circulation, with particular attention to the nitric oxide (NO)/cGMP pathway. Mice were placed under hypoxia in utero 5 days before delivery and for 5 days after birth. Pups were then bred in normoxia until adulthood. Adults born in hypoxia displayed an altered regulation of pulmonary vascular tone with higher right ventricular pressure in normoxia and increased sensitivity to acute hypoxia compared with controls. Perinatal hypoxia dramatically decreased endothelium-dependent relaxation induced by ACh in adult pulmonary arteries (PAs) but did not influence NO-mediated endothelium-independent relaxation. The M3muscarinic receptor was implicated in the relaxing action of ACh and M1muscarinic receptor (M1AChR) in its vasoconstrictive effects. Pirenzepine or telenzepine, two preferential inhibitors of M1AChR, abolished the adverse effects of perinatal hypoxia on ACh-induced relaxation. M1AChR mRNA expression was increased in lungs and PAs of mice born in hypoxia. The phosphodiesterase 1 (PDE1) inhibitor vinpocetine also reversed the decrease in ACh-induced relaxation following perinatal hypoxia, suggesting that M1AChR-mediated alteration of ACh-induced relaxation is due to the activation of calcium-dependent PDE1. Therefore, perinatal hypoxia leads to an altered pulmonary circulation in adulthood with vascular dysfunction characterized by impaired endothelium-dependent relaxation and M1AChR plays a predominant role. This raises the possibility that muscarinic receptors could be key determinants in pulmonary vascular diseases in relation to “perinatal imprinting.”
Lung-selective gene responses to alveolar hypoxia: potential role for the bone morphogenetic antagonist gremlin in pulmonary hypertension
Authors: Costello Christine M. , Howell Katherine , Cahill Edwina , McBryan Jean , Konigshoff Melanie , Eickelberg Oliver , Gaine Sean , Martin Finian , McLoughlin Paul
Published: May 2008

Pulmonary hypoxia is a common complication of chronic lung diseases leading to the development of pulmonary hypertension. The underlying sustained increase in vascular resistance in hypoxia is a response unique to the lung. Thus we hypothesized that there are genes for which expression is altered selectively in the lung in response to alveolar hypoxia. Using a novel subtractive array strategy, we compared gene responses to hypoxia in primary human pulmonary microvascular endothelial cells (HMVEC-L) with those in cardiac microvascular endothelium and identified 90 genes (forming 9 clusters) differentially regulated in the lung endothelium. From one cluster, we confirmed that the bone morphogenetic protein (BMP) antagonist, gremlin 1, was upregulated in the hypoxic murine lung in vivo but was unchanged in five systemic organs. We also demonstrated that gremlin protein was significantly increased by hypoxia in vivo and inhibited HMVEC-L responses to BMP stimulation in vitro. Furthermore, significant upregulation of gremlin was measured in lungs of patients with pulmonary hypertensive disease. From a second cluster, we showed that CXC receptor 7, a receptor for the proangiogenic chemokine CXCL12, was selectively upregulated in the hypoxic lung in vivo, confirming that our subtractive strategy had successfully identified a second lung-selective hypoxia-responsive gene. We conclude that hypoxia, typical of that encountered in pulmonary disease, causes lung-specific alterations in gene expression. This gives new insights into the mechanisms of pulmonary hypertension and vascular loss in chronic lung disease and identifies gremlin 1 as a potentially important mediator of vascular changes in hypoxic pulmonary hypertension.
Bradynema listronoti n. sp. (Nematoda: Allantonematidae), a parasite of the carrot weevil Listronotus oregonensis (Coleoptera: Curculionidae) in Quebec, Canada
Authors: Zeng Yongsan , Giblin-Davis Robin M. , Ye Weimin , Bélair Guy , Boivin Guy , Thomas Kelley
Published: May 2008

Bradynema listronoti n. sp. was collected from the haemocoel of adults and
the environment of the carrot weevil, Listronotus oregonensis in Quebec,
Canada. It is the first species of Bradynema to be reported from weevils and
is described and illustrated herein. Bradynema listronoti n. sp. appears to
be closest to B. trixagi because of the shared characteristic of a peloderan
bursa in males which is not present in the other seven described species in
the genus. Bradynema listronoti n. sp. can be differentiated from all
members of the genus by the possession of a degenerate, but sometimes
visible, stylet remnant, non-degenerate pharynx in males and by the often
dorsally-curved C-shaped body (ventral side is convex) of parasitic females.
The vestigial stylet in all stages argues for placement of B. listronoti n.
sp. within the genus Bradynema, but some characteristics, such as a
non-degenerate pharynx in males, suggest placement in a new genus or
affinities with other genera in the Allantonematidae, e.g., Allantonema.
Molecular analysis of the near full length SSU, D2/D3 expansion segments of
the large subunit (LSU) rDNA and partial mitochondrial DNA COI (mtCOI)
suggest that this nematode is unique and D2/D3 analysis supports monophyly
with B. rigidum, the only other member of the genus to be sequenced.
Studies on the effect of mycorrhization of potato roots on the hatching activity of potato root leachate towards the potato cyst nematodes, Globodera pallida and G. rostochiensis
Authors: Deliopoulos Thomas , Devine Ken J. , Haydock Patrick P.J. , Jones Peter W.
Published: May 2008

Successful mycorrhization of potato plants cv. Golden Wonder was achieved
with three commercial preparations of arbuscular mycorrhizal fungi (AMF):
Vaminoc (mixed-isolate inoculum) and two of its components, Glomus
intraradices and Glomus mosseae. Potato cyst nematode hatching assays were
conducted on the potato root leachate (PRL) produced by inoculated and
non-inoculated potato plants to examine the effect of AMF inoculation on the
hatching response of the two PCN species, Globodera rostochiensis and G.
pallida. The overall hatch response of G. rostochiensis to the potato root
leachate was greater than G. pallida. Root leachates from Vaminoc- and G.
mosseae-inoculated plants were found to stimulate the hatch of G. pallida in
the first 3 weeks after shoot emergence. Fractionation of root leachates
with standardised carbon content by Sephadex G-10 chromatography revealed
multiple AMF effects on hatching factor (HF) production. Root leachates from
Vaminoc-inoculated plants contained markedly more G. pallida-active HF than
all other treatments; by contrast, PRL from the three AMF treatments
exhibited little variation in the quantity of G. rostochiensis-active HF
produced. Several HF were PCN species-specific or species-selective, with
those resolved from the G. intraradices and G. mosseae PRL profiles
exhibiting an apparent preference for G. rostochiensis rather than G.
pallida. Mycorrhization also significantly increased the root dry weight of
plants.
Three new and one known species of the genus Enchodelus Thorne, 1939 (Nematoda: Dorylaimida) from India
Authors: Mushtaq Peerzada , Baniyamuddin Md. , Ahmad Wasim
Published: May 2008

Three new and one known species of the genus Enchodelus are described and
illustrated from India. Enchodelus bongersi sp. n. has 1.3-1.7 mm long body;
lip region offset by constriction; amphid with duplex fovea; odontostyle
13.5-14.5 μm long; rod-like odontophore lacking basal swellings or flanges,
and conoid, ventrally curved, tail with finely rounded terminus. Enchodelus
tropicus sp. n. has 0.97-1.11 mm long body; lip region offset by depression;
amphids with duplex fovea; odontostyle 15-16 μm long; odontophore simple,
rod-like, lacking basal flanges; vagina with well developed pars refringens
and conoid, ventrally curved tail with finely rounded terminus. Enchodelus
meghalayensis sp. n. has 0.97-1.19 mm long body; lip region offset by
depression; amphids stirrup-shaped; odontostyle 12-13 μm long; odontophore
simple, rod-like, lacking basal flanges; pars refringens vaginae absent;
spicules 40-46 μm long; 4-6 irregularly spaced ventromedian supplements and
conoid, ventrally curved tail with finely rounded terminus. Enchodelus
zonatus is redescribed together with the first report of its male.
Nematodes of the order Rhabditida from Tehran province, Iran. The family Panagrolaimidae with description of Halicephalobus persicus sp. n. and a key to species of Halicephalobus Timm, 1956
Authors: Shokoohi Ebrahim , Abolafia Joaquín , Zad Javad
Published: May 2008

Three species of the family Panagrolaimidae are described from mainly natural areas in Tehran province, Iran and a new species of the genus Halicephalobus is described and a key to species identification provided. Halicephalobus persicus sp. n. is characterised by a body length of 204-246 μm long in females, lateral field with two incisures, lip region with six flat, slightly separated, lips, pharynx with swollen bulb-shaped metacorpus, pharyngeal corpus 2.5-2.6 times isthmus length, female tail subcylindrical with fine mucro (40-53 μm; c = 4.4-5.2; c′ = 6.9-12.3). Iranian populations of three other previously known species were studied, viz. Propanagrolaimus hygrophilus, Panagrolaimus dendroctoni and P. rigidus, all being reported from Iran for the first time. The species are described, measured and figured.
Meloidogyne ethiopica, a major root-knot nematode parasitising Vitis vinifera and other crops in Chile
Authors: Carneiro Regina M.D.G. , Almeida Maria Ritta A. , Cofcewicz Eliz T. , Magunacelaya Juan Carlos , Aballay Erwin
Published: May 2008

Enzyme phenotypes, specifically esterases (EST) and malate dehydrogenase
(MDH), were used to characterise different species of Meloidogyne from
Chile. Esterase activity was highly polymorphic and was the most useful in
the identification of the different species. Using this enzyme it is
possible to characterise and identify M. ethiopica in about 80% of samples
on grapevine, kiwi and tomatoes. Another three species, M. javanica, M.
hapla and M. arenaria, were identified on tomatoes, kiwi and pomegranate
with only one or a few populations. It was possible to detect minor atypical
(unidentified) phenotypes, generally in mixed populations with M. ethiopica.
Only the profiles N1 and H1 of MDH were detected. N1 was not specific and H1
allowed identification of M. hapla. Contaminated nursery stock has probably
resulted in serious infestation by M. ethiopica in vineyards in various
localities in Chile.
Movement of the nematode, Phasmarhabditis hermaphrodita, in a structurally heterogeneous environment
Authors: Hapca Simona M. , Budha Prem , Crawford John W. , Young Iain M.
Published: May 2008

We consider the effect of structural heterogeneity on the movement of the
slug-parasitic nematode, Phasmarhabditis hermaphrodita. The study involves
image recording and analysis of nematode movement on a homogeneous layer of
technical agar compared to movement of nematodes in a structurally
heterogeneous environment that was created by adding sand particles to the
plates of agar. Features of nematode trail, such as speed, turning angle
distribution, fractal dimension and mean square displacement, were
calculated for each treatment. The presence of sand particles significantly
reduced the speed of nematodes and affected the distribution of the turning
angle with an increased tendency for moving forward or radically changing
the direction of movement. Also, the power-law pattern of the mean square
displacement changed, suggesting that nematode dispersal capacity became
slower, from super-diffusive in homogeneous agar to sub-diffusive in the
presence of sand particles. Further, the correlation in step length and
turning angles was computed as a function of lags between steps and used to
identify memory effects on nematode movement. While in the homogeneous
environment movement was characterised by strong temporal correlations; the
impact of sand particles was to reduce these correlations between steps. The
results suggest that the presence of structural heterogeneity introduces a
new bias into the movement, which plays an important role in complex
environments where the nematode movement may be obstructed by soil
particles.
Polyphenoloxidase is induced by methyljasmonate and Meloidogyne javanica in soybean roots but is not involved in resistance
Authors: Shimizu Milton Massao , Mazzafera Paulo
Published: May 2008

The role of the enzyme polyphenoloxidase (PPO) in the response of two soybean
varieties, Hartwig (resistant) and Cristalina (susceptible), to Meloidogyne
javanica was studied in plants where root systems were exposed to the known
PPO inducer, methyljasmonate. Chlorogenic acid was the best substrate for
root PPO. Treatment of both varieties with 100 and 400 μM methyljasmonate
solutions induced a similar increase in enzyme activity 72 h after
treatment. Inoculation of roots with second-stage juveniles (J2) induced PPO
increase in cv. Cristalina but not in cv. Hartwig. Moreover, combined
treatment of methyljasmonate and J2 inoculation enhanced PPO activity in
both varieties. Two PPO cDNAs were isolated from the roots of the resistant
variety 48 h after J2 inoculation, and Southern blot experiments in both
varieties, using GmPPOJH1 and GmPPOJH2 cDNAs as probes, indicated that PPOs
are represented by a multigene family in soybean. RT-PCR assays showed more
GmPPOJH1 transcripts in plants treated with methyljasmonate and infected
with nematodes, where high PPO activity was also observed. Plants treated
with methyljasmonate and infected with J2 showed a marked decrease of
nematode population 35 days after inoculation. These findings suggest that
methyljasmonate triggers a resistant response in soybean roots to M.
javanica but PPO is not involved in the resistance process.
Screening of edible soybean varieties for resistance to the root-knot nematode, Meloidogyne incognita, under field conditions
Authors: Adegbite Ayodele
Published: May 2008

In spite of the economic potential of edible soybean, the crop is attacked by pests and diseases, including the root-knot nematode, Meloidogyne incognita, which is the most troublesome plant-parasitic nematode in the tropics. Field studies were conducted in 2004 and 2005 to assess the reaction of 34 varieties of soybean for resistance to natural infestation of M. incognita. Ten weeks after planting, ten randomly selected plants were observed for root galls and nodules. Plant height, days to 50% flowering, days to maturity, 100 seed weight and yield were also recorded. Root galling varied significantly among soybean varieties. Root galling correlated negatively with number of pods and leaves; however, there was positive correlation between root gall and stem girth when all 34 varieties were considered. Of the 34 varieties, TGM 344, TGM 1784 and TGX 1448-2E were the most resistant with reproduction factors of 0.54, 0.56 and 0.54, respectively. Ten varieties exhibited tolerance, four were hyper-susceptible while the rest were susceptible to root-knot nematode.
Low temperature induces two growth-arrested stages and change of secondary metabolites in Bursaphelenchus xylophilus
Authors: Zhao Li Lin , Wei Wei , Kulhavy David L. , Zhang Xing Yao , Sun Jiang Hua
Published: May 2008

The third-stage dispersal juvenile (JIII) is the stage for survival and
dispersal in the winter of the pine wood nematode, Bursaphelenchus
xylophilus. Through investigations at different temperatures, we found two
kinds of growth-arrested development, including the adult longevity
extension and JIII formation induced by low temperature. They showed similar
characters: densely packed lipid droplets and extended longevity. We
considered that there were four stages in the formation of growth-arrested
stages: induction, growth-arrested pathway, growth-arrested development and
cold-tolerance duration. Moreover, at 4°C there were significant changes in
secondary metabolites, which may be related to signal communication and
metabolism associated with the formation of growth-arrested stages. The
results suggested that low temperature was necessary for the dispersal of
pine wood nematode and influenced distribution and intensity of pine
wilt.
Perceptions of Police Disrespect During Vehicle Stops: A Race-Based Analysis
Authors: Warren Patricia Y.
Published: May 2008

Blacks and Whites perceive American social institutions in very different terms, and views of the police are no exception. Prior research has consistently demonstrated that race is one of the most salient predictors of attitudes toward the police, with African Americans expressing more dissatisfaction than Whites. The purpose of this research is to evaluate this issue by examining the relative influence of vicarious experience and more general trust in social institutions on Black-White differences in perceptions of disrespect by the police. Using survey data from the North Carolina Highway Traffic Study, the results suggest that vicarious experience and more long-standing trust in social institutions influence the likelihood that respondents will perceive police as disrespectful.
Gravitating toward War
Authors: Hegre Håvard
Published: May 2008

Countries have better abilities and stronger incentives to engage in militarized conflicts the larger and more powerful they are. The article applies Zipf's notion of a ``gravity model'' to the risk of interstate conflict and argues that the empirical relationship between size and distance and conflict is stronger than any other identified in dyadic statistical studies of interstate conflict. Most empirical studies of interstate conflict fail to take size properly into account. The article shows that controlling for size variables improves the estimation of other variables of interest, and it explores the impact of omitting size variables for the investigation of the power preponderance versus power parity debate. The results indicate that even though a power capability ratio variable suggests asymmetric dyads are less conflict-prone, the risk-increasing effect of power itself means that a unilateral increase of power in one country increases the risk of conflict.
Facilitating Adaptive Emotional Analysis: Distinguishing Distanced-Analysis of Depressive Experiences From Immersed-Analysis and Distraction
Authors: Kross Ethan , Ayduk Ozlem
Published: May 2008

Two studies examined the psychological processes that facilitate adaptive emotional analysis. In Study 1, participants recalled a depression experience and then analyzed their feelings from either a self-immersed (immersed-analysis) or self-distanced (distanced-analysis) perspective. Participants in the distanced-analysis group focused less on recounting their experience and more on reconstruing it, which in turn led to lower levels of depressed affect. Furthermore, comparisons to a distraction group indicated that distanced-analysis was as effective as distraction in reducing depressed affect relative to the immersed-analysis group. Study 2 replicated these findings and showed that both 1 day and 7 days after the experimental manipulations, participants in the distanced-analysis group remained buffered against depressed affect and reported experiencing fewer recurring thoughts about their depression experience over time compared to both the immersed-analysis and distraction groups.
Person Theories: Their Temporal Stability and Relation to Intertrait Inferences
Authors: Poon Connie S. K. , Koehler Derek J.
Published: May 2008

This article tests whether individual differences in inferring one trait from another (intertrait inferences) can be linked to lay beliefs about the malleability of personality (person theories). It finds that holding the belief that personality is malleable (incremental theory) rather than fixed (entity theory) at the time of inferences is associated with less extreme inferences involving semantically related (but not unrelated) traits. Although person theories have been assumed to be stable over time, existing short-term test—retest coefficients do not capture their instability over a longer period. These results can illuminate interrater discrepancies in assessments of personality pathology and job performance, enrich understanding of such phenomena as stereotyping and impression formation, refine the interpretation of past research involving person theories, and inform research planning.
The Effects of Performance Feedback and Goal Setting on Oral Reading Fluency Within Curriculum-Based Measurement
Authors: Conte Kristin L. , Hintze John M.
Published: May 2008

This study assessed the effects of two types of goal-setting graphing procedures used within curriculum-based measurement (CBM) to provide performance feedback to students regarding oral reading fluency. Eighteen second-grade students were assigned to one of three experimental conditions: dynamic goal line, static goal line, and control. Calculation of effect sizes for the treatment conditions suggested that students receiving biweekly performance feedback toward short-term (biweekly) or long-term (eight-week) goals evidenced educationally relevant and noticeable change in oral reading fluency compared with a no-treatment control.
Differences in Reading Performance Between Students with and without Learning Disabilities Using the Woodcock Diagnostic Reading Battery
Authors: Oettinger Montani Teresa , Frawley Patricia , Smith Lisa F.
Published: May 2008

In this study we investigated differences in reading performance between 30 students in a suburban school district identified as having a learning disability and 30 students without a learning disability matched on the basis of grade and gender. All participants were in the third or fourth grade and were tested using the Woodcock Diagnostic Reading Battery (WDRB). Results indicated that all but three of the 10 subtests of the WDRB produced significant differences between the groups. The three subtests that did not reach significance were Oral Vocabulary, Listening Comprehension, and Memory for Sentences, all of which address oral language rather than letters or symbols. Results are discussed in terms of practical applications of the WDRB with students diagnosed with learning disabilities, as well as with other noncognitive indicators of reading performance.
Parent, Teacher, and Self-Report of Problem and Adaptive Behaviors in Children and Adolescents with Asperger Syndrome
Authors: Barnhill Gena P. , Hagiwara Taku , Myles Brenda Smith , Simpson Richard L. , Brick Megan L. , Griswold Deborah E.
Published: May 2008

The present study examined perceptions of the social problems and adaptive behaviors of children and youth with Asperger Syndrome. Parents and teachers used the Behavior Assessment System for Children (BASC) (Reynolds & Kamphaus, 1992) to evaluate 20 children and youth with Asperger Syndrome. In addition, the 20 students using the BASC self-report instrument evaluated their social problems and adaptive behavior. Findings are discussed relative to better understanding and planning for the needs of children and youth with Asperger Syndrome and their families.
Technical Adequacy of General Outcome Measures for Middle School Mathematics
Authors: Foegen Anne
Published: May 2008

This study examined three aspects of technical adequacy with respect to two general outcome measures in mathematics. The first two aspects were the effects of aggregating scores and correcting for random guessing on the reliability and validity of the measures. The third issue was the extent to which the measures were sensitive to changes in student performance. One hundred and five sixth-grade students completed two general outcome measures (basic facts and estimation) weekly for a 10-week period. With respect to aggregation, the results indicated that while fluency with basic facts is measured quite precisely with a single score, aggregation of scores for the estimation task increases both reliability and validity. Correcting the estimation scores for random guessing is recommended to increase criterion validity. Analyses of sensitivity to growth revealed that although both the fact and estimation measures reflect statistically significant changes across the 10-week period, the fact measure is likely to have greater practical significance. The article closes with a discussion of the relative merits of the measures for special education practice.
Reading Assessment and Instructional Practices in Special Education
Authors: Arthaud Tamara J. , Vasa Stanley F. , Steckelberg Allen L.
Published: May 2008

This study analyzed the instructional reading methods and reading assessment practices employed by K-12 special education teachers. Eight hundred special education teachers from four Midwestern states were surveyed regarding the frequency of use and usefulness of standardized and informal reading assessment practices and the frequency with which they used various reading instructional techniques. Responses were analyzed to determine percent of teachers employing each technique and the mean rating of usefulness assigned to each. Analysis included examination of the relationships between grade levels and instructional settings and teachers' preferences for reading instructional and assessment practices. The survey found that reading assessment practices present in the literature are not commonly used by special education teachers.
Curriculum-Based Measurement in Assessing Bilingual Students: A Promising New Direction
Authors: Bentz Johnell , Pavri Shireen
Published: May 2008

There is growing concern that current methods of assessing students from linguistically and culturally diverse backgrounds are sometimes biased against the student. For example, traditional forms of measuring English reading acquisition may demonstrate that a student has a learning disability or cognitive delay, when in fact; the student is merely having difficulty learning English. Alternative assessment methods are needed to monitor the English reading acquisition for these bilingual students for two reasons: (a) to ensure that they are not misidentified as needing special education and (b) to ensure that students who are in need of special education services receive the educational support necessary to be successful in school. This article discusses problems with traditional methods of assessing bilingual students and describes curriculum-based measurement (CBM) for use with bilingual Hispanic students. Additional information about the features of CBM is presented along with issues related to the use of CBM with bilingual Hispanic students.