bluuebunny/crossref_metadata_2025_split huggingface dataset:
Psychiatric morbidity in two low birth weight groups assessed by diagnostic interview in young adulthood
Authors: Lund Line K , Vik Torstein , Skranes Jon , Brubakk Ann‐Mari , Indredavik Marit S 
Published: December 2010

AbstractAim:  To study the prevalence and characteristics of psychiatric symptoms and disorders in young adults born with low birth weight.Methods:  At 20 years of age 44 very low birth weight (VLBW: birth weight ≤1500 g), 55 term born small for gestational age (SGA: birth weight <10th percentile) and 75 control subjects born 1986–1988 were assessed using the interview Schedule for Affective Disorders and Schizophrenia for School‐age children and Structured Clinical Interview for DSM‐IV Personality Disorders, Children’s Global Assessment Scale and Attention deficit hyperactivity disorder (ADHD) Rating Scale IV; self‐report and parent report.Results:  Fourteen (33%) VLBW versus six (8%) control participants had a definite psychiatric disorder: OR = 5.6 (1.9–15.9). In the term SGA group, 14 (26%) had a disorder: OR = 3.9 (1.4–11.0) vs controls. Anxiety disorders and ADHD were the most frequent diagnoses. The differences were not explained by gender, assessment age or parental socioeconomic status. ADHD Rating Scale mean scores were higher in parent reports in the VLBW group and in self‐reports in the term SGA group compared with the control group.Conclusion:  Children born with low birth weight whether caused by preterm birth or by growth retardation at term seem to be at increased risk for psychiatric disorders as young adults.
Functional and structural analyses of N‐acylsulfonamide‐linked dinucleoside inhibitors of RNase A
Authors: Thiyagarajan Nethaji , Smith Bryan D. , Raines Ronald T. , Acharya K. Ravi 
Published: December 2010

Molecular probes are useful for both studying and controlling the functions of enzymes and other proteins. The most useful probes have high affinity for their target, along with small size and resistance to degradation. Here, we report on new surrogates for nucleic acids that fulfill these criteria. Isosteres in which phosphoryl [R–O–P(O2−)–O–R′] groups are replaced with N‐acylsulfonamidyl [R–C(O)–N−–S(O2)–R′] or sulfonimidyl [R–S(O2)–N−–S(O2)–R′] groups increase the number of nonbridging oxygens from two (phosphoryl) to three (N‐acylsulfonamidyl) or four (sulfonimidyl). Six such isosteres were found to be more potent inhibitors of catalysis by bovine pancreatic RNase A than are parent compounds containing phosphoryl groups. The atomic structures of two RNase A·N‐acylsulfonamide complexes were determined at high resolution by X‐ray crystallography. The N‐acylsulfonamidyl groups were observed to form more hydrogen bonds with active site residues than did the phosphoryl groups in analogous complexes. These data encourage the further development and use of N‐acylsulfonamides and sulfonimides as antagonists of nucleic acid‐binding proteins.Database
Structural data for the two RNase A complexes are available in the Protein Data Bank under accession numbers 2xog and 2xoi
Molecular Indications of Protein Damage in Adenoviruses after UV Disinfection
Authors: Eischeid Anne C. , Linden Karl G. 
Published: December 2010

ABSTRACT
Adenoviruses are resistant to monochromatic, low-pressure (LP) UV disinfection—but have been shown to be susceptible to inactivation by polychromatic, medium-pressure (MP) UV—when assayed using cell culture infectivity. One possible explanation for the difference between UV lamp types is that the additional UV wavelengths emitted by MP UV enable it to cause greater damage to viral proteins than LP UV. The objective of this study was to examine protein damage in adenoviruses treated with LP and MP UV. Results show that MP UV is more effective at damaging viral proteins at high UV doses, though LP UV caused some damage as well. To our knowledge, this study is the first to investigate protein damage in UV-treated adenovirus, and the overview presented here is expected to provide a basis for further, more detailed work.
Antimicrobial Resistance in GenericEscherichia coliIsolates from Wild Small Mammals Living in Swine Farm, Residential, Landfill, and Natural Environments in Southern Ontario, Canada
Authors: Allen Samantha E. , Boerlin Patrick , Janecko Nicol , Lumsden John S. , Barker Ian K. , Pearl David L. , Reid-Smith Richard J. , Jardine Claire 
Published: December 2010

ABSTRACTTo assess the impacts of different types of human activity on the development of resistant bacteria in the feces of wild small mammals, we compared the prevalences and patterns of antimicrobial resistance and resistance genes in genericEscherichia coliandSalmonella entericaisolates from fecal samples collected from wild small mammals living in four environments: swine farms, residential areas, landfills, and natural habitats. Resistance to antimicrobials was observed inE. coliisolates from animals in all environments: 25/52 (48%) animals trapped at swine farms, 6/69 (9%) animals trapped in residential areas, 3/20 (15%) animals trapped at landfills, and 1/22 (5%) animals trapped in natural habitats. Animals trapped on farms were significantly more likely to carryE. coliisolates with resistance to tetracycline, ampicillin, sulfisoxazole, and streptomycin than animals trapped in residential areas. The resistance genessul2,aadA, andtet(A) were significantly more likely to be detected inE. coliisolates from animals trapped on farms than from those trapped in residential areas. ThreeS. entericaserotypes (Give, Typhimurium, and Newport) were recovered from the feces of 4/302 (1%) wild small mammals. AllSalmonellaisolates were pansusceptible. Our results show that swine farm origin is significantly associated with the presence of resistant bacteria and resistance genes in wild small mammals in southern Ontario, Canada. However, resistant fecal bacteria were found in small mammals living in all environments studied, indicating that environmental exposure to antimicrobials, antimicrobial residues, resistant bacteria, or resistance genes is widespread.
Induction of Fatty Acid Composition Modifications and Tolerance to Biocides in
Salmonella enterica
Serovar Typhimurium by Plant-Derived Terpenes
Authors: Dubois-Brissonnet Florence , Naïtali Murielle , Mafu Akier Assanta , Briandet Romain 
Published: December 2010

ABSTRACT

To enhance food safety and stability, the food industry tends to use natural antimicrobials such as plant-derived compounds as an attractive alternative to chemical preservatives. Nonetheless, caution must be exercised in light of the potential for bacterial adaptation to these molecules, a phenomenon previously observed with other antimicrobials. The aim of this study was to characterize the adaptation of
Salmonella enterica
serovar Typhimurium to sublethal concentrations of four terpenes extracted from aromatic plants: thymol, carvacrol, citral, and eugenol, or combinations thereof. Bacterial adaptation in these conditions was demonstrated by changes in membrane fatty acid composition showing (i) limitation of the cyclization of unsaturated fatty acids to cyclopropane fatty acids when cells entered the stationary phase and (ii) bacterial membrane saturation. Furthermore, we demonstrated an increased cell resistance to the bactericidal activity of two biocides (peracetic acid and didecyl dimethyl ammonium bromide). The implications of membrane modifications in terms of hindering the penetration of antimicrobials through the bacterial membrane are discussed.
Characterization of a Novel β-Xylosidase, XylC, from
Thermoanaerobacterium saccharolyticum
JW/SL-YS485
Authors: Shao Weilan , Xue Yemin , Wu Ailian , Kataeva Irina , Pei Jianjun , Wu Huawei , Wiegel Juergen 
Published: December 2010

ABSTRACT

The 1,914-bp open reading frame of
xylC
from
Thermoanaerobacterium saccharolyticum
JW/SL-YS485 encodes a calculated 73-kDa β-xylosidase, XylC, different from any glycosyl hydrolase in the database and representing a novel glycohydrolase family. Hydrolysis occurred under retention of the anomeric configuration, and transglycosylation occurred in the presence of alcohols as acceptors. With the use of vector pHsh, expression of XylC, the third β-xylosidase in this bacterium, increased approximately 4-fold when a loop within the translational initiation region in the mRNA was removed by site-directed mutagenesis. The increased expression of
xylC

m

is due to removal of a stem-loop structure without a change of the amino acid sequence of the heterologously expressed enzyme (XylC
rec
). When gel filtration was applied, purified XylC had molecular masses of 210 kDa and 265 kDa using native gradient gel electrophoresis. The protein consisted of 78-kDa subunits based on SDS gel electrophoresis and contained 6% carbohydrates. XylC and XylC
rec
exhibited maximum activity at 65°C and pH
65°C
6.0, a 1-h half-life at 67°C, a

K
m

for
p
-nitrophenyl-β-
d
-xyloside of 28 mM, and a
V
max
of 276 U/mg and retained 70% activity in the presence of 200 mM xylose, suggesting potential for industrial applications.
Cytosolic Localization of Acetohydroxyacid Synthase Ilv2 and Its Impact on Diacetyl Formation during Beer Fermentation
Authors: Dasari Suvarna , Kölling Ralf 
Published: December 2010

ABSTRACT

Diacetyl (2,3-butanedione) imparts an unpleasant “butterscotch-like” flavor to alcoholic beverages such as beer, and therefore its concentration needs to be reduced below the sensory threshold before packaging. We examined the mechanisms that lead to highly elevated diacetyl formation in petite mutants of
Saccharomyces cerevisiae
during beer fermentations. We present evidence that elevated diacetyl formation is tightly connected to the mitochondrial import of acetohydroxyacid synthase (Ilv2), the key enzyme in the production of diacetyl. Our data suggest that accumulation of the matrix-targeted Ilv2 preprotein in the cytosol is responsible for the observed high diacetyl levels. We could show that the Ilv2 preprotein accumulates in the cytosol of petite yeasts. Furthermore, expression of an Ilv2 variant that lacks the N-terminal mitochondrial targeting sequence and thus cannot be imported into mitochondria led to highly elevated diacetyl levels comparable to a petite strain. We further show that expression of a mutant allele of the γ-subunit of the F
1
-ATPase (
ATP3-5
) could be an attractive way to reduce diacetyl formation by petite strains.
Transcriptional Analysis of a
Photorhabdus
sp. Variant Reveals Transcriptional Control of Phenotypic Variation and Multifactorial Pathogenicity in Insects
Authors: Lanois A. , Pages S. , Bourot S. , Canoy A.-S. , Givaudan A. , Gaudriault S. 
Published: December 2010

ABSTRACT

Photorhabdus luminescens
lives in a mutualistic association with entomopathogenic nematodes and is pathogenic for insects. Variants of
Photorhabdus
frequently arise irreversibly and are studied because they have altered phenotypic traits that are potentially important for the host interaction. VAR* is a colonial and phenotypic variant displaying delayed pathogenicity when directly injected into the insect,
Spodoptera littoralis
. In this study, we evaluated the role of transcriptomic modulation in determining the phenotypic variation and delayed pathogenicity of VAR* with respect to the corresponding wild-type form, TT01α. A
P. luminescens
microarray identified 148 genes as differentially transcribed between VAR* and TT01α. The net regulator status of VAR* was found to be significantly modified. We also observed in VAR* a decrease in the transcription of genes supporting certain phenotypic traits, such as pigmentation, crystalline inclusion, antibiosis, and protease and lipase activities. Three genes encoding insecticidal toxins (
pit
and
pirB
) or putative insecticidal toxins (
xnp2
) were less transcribed in VAR* than in the TT01α. The overexpression of these genes was not sufficient to restore the virulence of VAR* to the levels of ΤΤ01α, which suggests that the lower virulence of VAR* does not result from impaired toxemia in insects. Three loci involved in oxidative stress responses (
sodA
,
katE
, and the
hca
operon) were found to be downregulated in VAR*. This is consistent with the greater sensitivity of VAR* to H
2
O
2
and may account for the impaired bacteremia in the hemolymph of
S. littoralis
larvae observed with VAR*. In conclusion, we demonstrate here that some phenotypic traits of VAR* are regulated transcriptionally and highlight the multifactorial nature of pathogenicity in insects.
PseudomonasDiversity in Crude-Oil-Contaminated Intertidal Sand Samples Obtained after thePrestigeOil Spill
Authors: Mulet Magdalena , David Zoyla , Nogales Balbina , Bosch Rafael , Lalucat Jorge , García-Valdés Elena 
Published: December 2010

ABSTRACTThe Galicia seashore, in northwestern Spain, was one of the shorelines affected by thePrestigeoil spill in November 2002. The diversity of autochthonousPseudomonaspopulations present at two beaches (Carnota municipality) was analyzed using culture-independent and culture-dependent methods. The first analysis involved the screening of anrpoDgene library. The second involved the isolation of 94Pseudomonasstrains that were able to grow on selective media by direct plating or after serial enrichments on several carbon sources: biphenyl, gentisate, hexadecane, methylnaphthalene, naphthalene, phenanthrene, salicylate, xylene, and succinate. Eight denitrifyingPseudomonasstrains were also isolated by their ability to grow anaerobically with nitrate. The calculated coverage index forPseudomonasspecies was 89% when clones and isolates were considered together, and there were 29 phylospecies detected. The most abundant were members of the speciesP. stutzeri,P.putida,P. anguilliseptica, andP. oleovorans. Thirty-one isolates could not be identified at the species level and were considered representatives of 16 putative novelPseudomonasspecies. One isolate was considered representative of a novelP. stutzerigenomovar. Concordant results were obtained when the diversities of the cloned DNA library and the cultured strains were compared. The clone library obtained by therpoDPCR method was a useful tool for evaluatingPseudomonascommunities and also for microdiversity studies ofPseudomonaspopulations.
Bacteriophage Ecology in
Escherichia coli
and
Pseudomonas aeruginosa
Mixed-Biofilm Communities
Authors: Kay Matthew K. , Erwin Thomas C. , McLean Robert J. C. , Aron Gary M. 
Published: December 2010

ABSTRACT

Phage therapy is being reexamined as a strategy for bacterial control in medical and other environments. As microorganisms often live in mixed populations, we examined the effect of
Escherichia coli
bacteriophage λW60 and
Pseudomonas aeruginosa
bacteriophage PB-1 infection on the viability of monoculture and mixed-species biofilm and planktonic cultures. In mixed-species biofilm communities,
E. coli
and
P. aeruginosa
maintained stable cell populations in the presence of one or both phages. In contrast,
E. coli
planktonic populations were severely depleted in coculture in the presence of λW60. Both
E. coli
and
P. aeruginosa
developed phage resistance in planktonic culture; however, reduced resistance was observed in biofilm communities. Increased phage titers and reduced resistance in biofilms suggest that phage can replicate on susceptible cells in biofilms. Infectious phage could be released from mixed-culture biofilms upon treatment with Tween 20 but not upon treatment with chloroform. Tween 20 and chloroform treatments had no effect on phage associated with planktonic cells, suggesting that planktonic phage were not cell or matrix associated. Transmission electron microscopy showed bacteriophage particles to be enmeshed in the extracellular polymeric substance component of biofilms and that this substance could be removed by Tween 20 treatment. Overall, this study demonstrates how mixed-culture biofilms can maintain a reservoir of viable phage and bacterial populations in the environment.
The
yctCBA
Operon of
Yersinia ruckeri
, Involved in
In Vivo
Citrate Uptake, Is Not Required for Virulence
Authors: Navais Roberto , Méndez Jessica , Reimundo Pilar , Pérez-Pascual David , Gómez Esther , Guijarro José A. 
Published: December 2010

ABSTRACT

A three-gene operon, named
yctCBA
(

Y

ersinia

c

itrate

t

ransporter), induced by citrate and repressed by glucose was identified from a previously selected
in vivo
-induced (
ivi
) clone in the fish pathogen
Yersinia
ruckeri
. Interestingly, despite being an
ivi
clone, the drastic growth reduction of the
yctC
mutant in the presence of citrate, and the relatively high content of this compound in rainbow trout serum, the operon was not required for virulence.
Production of Secretory and Extracellular N-Linked Glycoproteins inEscherichia coli
Authors: Fisher Adam C. , Haitjema Charles H. , Guarino Cassandra , Çelik Eda , Endicott Christine E. , Reading Craig A. , Merritt Judith H. , Ptak A. Celeste , Zhang Sheng , DeLisa Matthew P. 
Published: December 2010

ABSTRACTTheCampylobacter jejuni pglgene cluster encodes a complete N-linked protein glycosylation pathway that can be functionally transferred intoEscherichia coli. In this system, we analyzed the interplay between N-linked glycosylation, membrane translocation and folding of acceptor proteins in bacteria. We developed a recombinant N-glycan acceptor peptide tag that permits N-linked glycosylation of diverse recombinant proteins expressed in the periplasm of glycosylation-competentE. colicells. With this “glycosylation tag,” a clear difference was observed in the glycosylation patterns found on periplasmic proteins depending on their mode of inner membrane translocation (i.e., Sec, signal recognition particle [SRP], or twin-arginine translocation [Tat] export), indicating that the mode of protein export can influence N-glycosylation efficiency. We also established that engineered substrate proteins targeted to environments beyond the periplasm, such as the outer membrane, the membrane vesicles, and the extracellular medium, could serve as substrates for N-linked glycosylation. Taken together, our results demonstrate that theC. jejuniN-glycosylation machinery is compatible with distinct secretory mechanisms inE. coli, effectively expanding the N-linked glycome of recombinantE. coli. Moreover, this simple glycosylation tag strategy expands the glycoengineering toolbox and opens the door to bacterial synthesis of a wide array of recombinant glycoprotein conjugates.
Identification of a Tyrosine Decarboxylase Gene (
tdcA
) in
Streptococcus thermophilus
1TT45 and Analysis of Its Expression and Tyramine Production in Milk
Authors: La Gioia Federica , Rizzotti Lucia , Rossi Franca , Gardini Fausto , Tabanelli Giulia , Torriani Sandra 
Published: December 2010

ABSTRACT

In this study, a tyrosine decarboxylase gene (
tdcA
) was identified in 1 among 83
Streptococcus thermophilus
strains tested. Its sequence, nearly identical to that of a
tdcA
of
Lactobacillus curvatus
, indicated a horizontal gene transfer event. Transcription in milk and the formation of critical levels of tyramine were observed in the presence of tyrosine.
Lactobacillus plantarum
Extracellular Chitin-Binding Protein and Its Role in the Interaction between Chitin, Caco-2 Cells, and Mucin
Authors: Sánchez Borja , González-Tejedo Carmen , Ruas-Madiedo Patricia , Urdaci María C. , Margolles Abelardo 
Published: December 2010

ABSTRACT

In the present work, we describe the adhesion capabilities of a recombinant
Lactococcus lactis
strain producing an extracellular protein from
Lactobacillus plantarum
. Our results show that this protein may offer the bacterium a mechanism to bind to
N
-acetylglucosamine-containing polymers, such as human mucins, present in different environments.
Neutrophilic Iron-Oxidizing “
Zetaproteobacteria
” and Mild Steel Corrosion in Nearshore Marine Environments
Authors: McBeth Joyce M. , Little Brenda J. , Ray Richard I. , Farrar Katherine M. , Emerson David 
Published: December 2010

ABSTRACT

Microbiologically influenced corrosion (MIC) of mild steel in seawater is an expensive and enduring problem. Little attention has been paid to the role of neutrophilic, lithotrophic, iron-oxidizing bacteria (FeOB) in MIC. The goal of this study was to determine if marine FeOB related to
Mariprofundus
are involved in this process. To examine this, field incubations and laboratory microcosm experiments were conducted. Mild steel samples incubated in nearshore environments were colonized by marine FeOB, as evidenced by the presence of helical iron-encrusted stalks diagnostic of the FeOB
Mariprofundus ferrooxydans
, a member of the candidate class “
Zetaproteobacteria.
” Furthermore,
Mariprofundus
-like cells were enriched from MIC biofilms. The presence of
Zetaproteobacteria
was confirmed using a
Zetaproteobacteria
-specific small-subunit (SSU) rRNA gene primer set to amplify sequences related to
M. ferrooxydans
from both enrichments and
in situ
samples of MIC biofilms. Temporal
in situ
incubation studies showed a qualitative increase in stalk distribution on mild steel, suggesting progressive colonization by stalk-forming FeOB. We also isolated a novel FeOB, designated
Mariprofundus
sp. strain GSB2, from an iron oxide mat in a salt marsh. Strain GSB2 enhanced uniform corrosion from mild steel in laboratory microcosm experiments conducted over 4 days. Iron concentrations (including precipitates) in the medium were used as a measure of corrosion. The corrosion in biotic samples (7.4 ± 0.1 mM) was significantly higher than that in abiotic controls (5.0 ± 0.1 mM). These results have important implications for the role of FeOB in corrosion of steel in nearshore and estuarine environments. In addition, this work shows that the global distribution of
Zetaproteobacteria
is far greater than previously thought.
Modeling of Pathogen Survival during Simulated Gastric Digestion
Authors: Koseki Shige , Mizuno Yasuko , Sotome Itaru 
Published: December 2010

ABSTRACT

The objective of the present study was to develop a mathematical model of pathogenic bacterial inactivation kinetics in a gastric environment in order to further understand a part of the infectious dose-response mechanism. The major bacterial pathogens
Listeria monocytogenes
,
Escherichia coli
O157:H7, and
Salmonella
spp. were examined by using simulated gastric fluid adjusted to various pH values. To correspond to the various pHs in a stomach during digestion, a modified logistic differential equation model and the Weibull differential equation model were examined. The specific inactivation rate for each pathogen was successfully described by a square-root model as a function of pH. The square-root models were combined with the modified logistic differential equation to obtain a complete inactivation curve. Both the modified logistic and Weibull models provided a highly accurate fitting of the static pH conditions for every pathogen. However, while the residuals plots of the modified logistic model indicated no systematic bias and/or regional prediction problems, the residuals plots of the Weibull model showed a systematic bias. The modified logistic model appropriately predicted the pathogen behavior in the simulated gastric digestion process with actual food, including cut lettuce, minced tuna, hamburger, and scrambled egg. Although the developed model enabled us to predict pathogen inactivation during gastric digestion, its results also suggested that the ingested bacteria in the stomach would barely be inactivated in the real digestion process. The results of this study will provide important information on a part of the dose-response mechanism of bacterial pathogens.
Interaction between the Candida albicans High-Osmolarity Glycerol (HOG) Pathway and the Response to Human β-Defensins 2 and 3
Authors: Argimón Silvia , Fanning Saranna , Blankenship Jill R. , Mitchell Aaron P. 
Published: December 2010

ABSTRACT

Human β-defensins 2 and 3 are small cationic peptides with antimicrobial activity against the fungal pathogen
Candida albicans
. We found that
hog1
and
pbs2
mutants were hypersensitive to treatment with these peptides, pointing to a role of the high-osmolarity glycerol (HOG) pathway in the response to defensin-induced cell injury.