bluuebunny/crossref_metadata_2025_split huggingface dataset:
Botrytis pseudocinerea Is a Significant Pathogen of Several Crop Plants but Susceptible to Displacement by Fungicide-Resistant B. cinerea Strains
Authors: Plesken Cecilia , Weber Roland W. S. , Rupp Sabrina , Leroch Michaela , Hahn Matthias 
Published: August 2015

ABSTRACT

Botrytis cinerea
is one of the most important pathogens worldwide, causing gray mold on a large variety of crops.
Botrytis pseudocinerea
has been found previously to occur together with
B. cinerea
in low abundance in vineyards and strawberry fields. Here, we report
B. pseudocinerea
to be common and sometimes dominant over
B. cinerea
on several fruit and vegetable crops in Germany. On apples with calyx end rot and on oilseed rape, it was the major gray mold species. Abundance of
B. pseudocinerea
was often negatively correlated with fungicide treatments. On cultivated strawberries, it was frequently found in spring but was largely displaced by
B. cinerea
following fungicide applications. Whereas
B. cinerea
strains with multiple-fungicide resistance were common in these fields,
B. pseudocinerea
almost never developed resistance to any fungicide even though resistance mutations occurred at similar frequencies in both species under laboratory conditions. The absence of resistance to quinone outside inhibitors in
B. pseudocinerea
was correlated with an intron in
cytB
preventing the major G143A resistance mutation. Our work indicates that
B. pseudocinerea
has a wide host range similar to that of
B. cinerea
and that it can become an important gray mold pathogen on cultivated plants.
Three Novel Lantibiotics, Ticins A1, A3, and A4, Have Extremely Stable Properties and Are Promising Food Biopreservatives
Authors: Xin Bingyue , Zheng Jinshui , Xu Ziya , Li Congzhi , Ruan Lifang , Peng Donghai , Sun Ming 
Published: August 2015

ABSTRACT

Lantibiotics are antimicrobial peptides with potential applications as the next generation of antimicrobials in the food industry and/or the pharmaceutical industry. Nisin has successfully been used as a food preservative for over 40 years, but its major drawback is its limited stability under neutral and alkaline pH conditions. To identify alternatives with better biochemical properties, we screened more than 100 strains of the
Bacillus cereus
group. Three novel lantibiotics, ticins A1 (4,062.98 Da), A3 (4,048.96 Da), and A4 (4,063.02 Da), which were highly thermostable (121°C for 30 min) and extremely pH tolerant (pH 2.0 to 9.0), were identified in
Bacillus thuringiensis
BMB3201. They all showed potent antimicrobial activities against all tested Gram-positive bacteria and greater activities than those of nisin A against
Bacillus cereus
and
Listeria monocytogenes
, two important foodborne pathogens. These three novel lantibiotics, with their extremely stable properties and potent antimicrobial activities, have the potential for use as biopreservatives.
Identification and Characterization of a Novel Staphylococcal Emetic Toxin
Authors: Ono Hisaya K. , Sato'o Yusuke , Narita Kouji , Naito Ikunori , Hirose Shouhei , Hisatsune Junzo , Asano Krisana , Hu Dong-Liang , Omoe Katsuhiko , Sugai Motoyuki , Nakane Akio 
Published: August 2015

ABSTRACTStaphylococcal enterotoxins (SEs) produced byStaphylococcus aureushave superantigenic and emetic activities, which cause toxic shock syndrome and staphylococcal food poisoning, respectively. Our previous study demonstrated that the sequence of SET has a low level of similarity to the sequences of other SEs and exhibits atypical bioactivities. Hence, we further explored whether there is an additional SET-related gene inS. aureusstrains. One SET-like gene was found in the genome ofS. aureusisolates that originated from a case of food poisoning, a human nasal swab, and a case of bovine mastitis. The deduced amino acid sequence of the SET-like gene showed 32% identity with the amino acid sequence of SET. The SET-like gene product was designated SElY. In the food poisoning and nasal swab isolates, mRNA encoding SElY was highly expressed in the early log phase of cultivation, whereas a high level of expression of this mRNA was found in the bovine mastitis isolate at the early stationary phase. To estimate whether SElY has both superantigenic and emetic activities, recombinant SElY was prepared. Cell proliferation and cytokine production were examined to assess the superantigenic activity of SElY. SElY exhibited superantigenic activity in human peripheral blood mononuclear cells but not in mouse splenocytes. In addition, SElY exhibited emetic activity in house musk shrews after intraperitoneal and oral administration. However, the stability of SElY against heating and pepsin and trypsin digestion was different from that of SET and SEA. From these results, we identified SElY to be a novel staphylococcal emetic toxin.
Highly Virulent Non-O157 Enterohemorrhagic Escherichia coli (EHEC) Serotypes Reflect Similar Phylogenetic Lineages, Providing New Insights into the Evolution of EHEC
Authors: Eichhorn Inga , Heidemanns Katrin , Semmler Torsten , Kinnemann Bianca , Mellmann Alexander , Harmsen Dag , Anjum Muna F. , Schmidt Herbert , Fruth Angelika , Valentin-Weigand Peter , Heesemann Jürgen , Suerbaum Sebastian , Karch Helge , Wieler Lothar H. 
Published: August 2015

ABSTRACT

Enterohemorrhagic
Escherichia coli
(EHEC) is the causative agent of bloody diarrhea and extraintestinal sequelae in humans, most importantly hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP). Besides the bacteriophage-encoded Shiga toxin gene (
stx
), EHEC harbors the locus of enterocyte effacement (LEE), which confers the ability to cause attaching and effacing lesions. Currently, the vast majority of EHEC infections are caused by strains belonging to five O serogroups (the “big five”), which, in addition to O157, the most important, comprise O26, O103, O111, and O145. We hypothesize that these four non-O157 EHEC serotypes differ in their phylogenies. To test this hypothesis, we used multilocus sequence typing (MLST) to analyze a large collection of 250 isolates of these four O serogroups, which were isolated from diseased as well as healthy humans and cattle between 1952 and 2009. The majority of the EHEC isolates of O serogroups O26 and O111 clustered into one sequence type complex, STC29. Isolates of O103 clustered mainly in STC20, and most isolates of O145 were found within STC32. In addition to these EHEC strains, STC29 also included
stx
-negative
E. coli
strains, termed atypical enteropathogenic
E. coli
(aEPEC), yet another intestinal pathogenic
E. coli
group. The finding that aEPEC and EHEC isolates of non-O157 O serogroups share the same phylogeny suggests an ongoing microevolutionary scenario in which the phage-encoded Shiga toxin gene
stx
is transferred between aEPEC and EHEC. As a consequence, aEPEC strains of STC29 can be regarded as post- or pre-EHEC isolates. Therefore, STC29 incorporates phylogenetic information useful for unraveling the evolution of EHEC.
Biosynthesis and Secretion of Indole-3-Acetic Acid and Its Morphological Effects on Tricholoma vaccinum-Spruce Ectomycorrhiza
Authors: Krause Katrin , Henke Catarina , Asiimwe Theodore , Ulbricht Andrea , Klemmer Sandra , Schachtschabel Doreen , Boland Wilhelm , Kothe Erika 
Published: August 2015

ABSTRACT

Fungus-derived indole-3-acetic acid (IAA), which is involved in development of ectomycorrhiza, affects both partners, i.e., the tree and the fungus. The biosynthesis pathway, excretion from fungal hyphae, the induction of branching in fungal cultures, and enhanced Hartig net formation in mycorrhiza were shown. Gene expression studies, incorporation of labeled compounds into IAA, heterologous expression of a transporter, and bioinformatics were applied to study the effect of IAA on fungal morphogenesis and on ectomycorrhiza.
Tricholoma vaccinum
produces IAA from tryptophan via indole-3-pyruvate, with the last step of this biosynthetic pathway being catalyzed by an aldehyde dehydrogenase. The gene
ald1
was found to be highly expressed in ectomycorrhiza and induced by indole-3-acetaldehyde. The export of IAA from fungal cells is supported by the multidrug and toxic extrusion (MATE) transporter Mte1 found in
T. vaccinum
. The addition of IAA and its precursors induced elongated cells and hyphal ramification of mycorrhizal fungi; in contrast, in saprobic fungi such as
Schizophyllum commune
, IAA did not induce morphogenetic changes. Mycorrhiza responded by increasing its Hartig net formation. The IAA of fungal origin acts as a diffusible signal, influencing root colonization and increasing Hartig net formation in ectomycorrhiza.
Exploring Vertical Transmission of Bifidobacteria from Mother to Child
Authors: Milani Christian , Mancabelli Leonardo , Lugli Gabriele Andrea , Duranti Sabrina , Turroni Francesca , Ferrario Chiara , Mangifesta Marta , Viappiani Alice , Ferretti Pamela , Gorfer Valentina , Tett Adrian , Segata Nicola , van Sinderen Douwe , Ventura Marco 
Published: August 2015

ABSTRACT

Passage through the birth canal and consequent exposure to the mother's microbiota is considered to represent the initiating event for microbial colonization of the gastrointestinal tract of the newborn. However, a precise evaluation of such suspected vertical microbiota transmission has yet to be performed. Here, we evaluated the microbiomes of four sample sets, each consisting of a mother's fecal and milk samples and the corresponding infant's fecal sample, by means of amplicon-based profiling supported by shotgun metagenomics data for two key samples. Notably, targeted genome reconstruction from microbiome data revealed vertical transmission of a
Bifidobacterium breve
strain and a
Bifidobacterium longum
subsp.
longum
strain from mother to infant, a notion confirmed by strain isolation and genome sequencing. Furthermore, PCR analyses targeting unique genes from these two strains highlighted their persistence in the infant gut at 6 months. Thus, this study demonstrates the existence of specific bifidobacterial strains that are common to mother and child and thus indicative of vertical transmission and that are maintained in the infant for at least relatively short time spans.
Burkholderia Diffusible Signal Factor Signals to Francisella novicida To Disperse Biofilm and Increase Siderophore Production
Authors: Dean Scott N. , Chung Myung-Chul , van Hoek Monique L. 
Published: August 2015

ABSTRACT

In many bacteria, the ability to modulate biofilm production relies on specific signaling molecules that are either self-produced or made by neighboring microbes within the ecological niche. We analyzed the potential interspecies signaling effect of the
Burkholderia
diffusible signal factor (BDSF) on
Francisella novicida
, a model organism for
Francisella tularensis
, and demonstrated that BDSF both inhibits the formation and causes the dispersion of
Francisella
biofilm. Specificity was demonstrated for the
cis
versus the
trans
form of BDSF. Using transcriptome sequencing, quantitative reverse transcription-PCR, and activity assays, we found that BDSF altered the expression of many
F. novicida
genes, including genes involved in biofilm formation, such as chitinases. Using a chitinase inhibitor, the antibiofilm activity of BDSF was also shown to be chitinase dependent. In addition, BDSF caused an increase in RelA expression and increased levels of (p)ppGpp, leading to decreased biofilm production. These results support our observation that exposure of
F. novicida
to BDSF causes biofilm dispersal. Furthermore, BDSF upregulated the genes involved in iron acquisition (
figABCD
), increasing siderophore production. Thus, this study provides evidence for a potential role and mechanism of diffusible signal factor (DSF) signaling in the genus
Francisella
and suggests the possibility of interspecies signaling between
Francisella
and other bacteria. Overall, this study suggests that in response to the interspecies DSF signal,
F. novicida
can alter its gene expression and regulate its biofilm formation.
Geographical and Temporal Structures of Legionella pneumophila Sequence Types in Comunitat Valenciana (Spain), 1998 to 2013
Authors: Sánchez-Busó Leonor , Coscollà Mireia , Palero Ferran , Camaró María Luisa , Gimeno Ana , Moreno Pilar , Escribano Isabel , López Perezagua María Mar , Colomina Javier , Vanaclocha Herme , González-Candelas Fernando 
Published: August 2015

ABSTRACT

Legionella pneumophila
is an accidental human pathogen associated with aerosol formation in water-related sources. High recombination rates make
Legionella
populations genetically diverse, and nearly 2,000 different sequence types (STs) have been described to date for this environmental pathogen. The spatial distribution of STs is extremely heterogeneous, with some variants being present worldwide and others being detected at only a local scale. Similarly, some STs have been associated with disease outbreaks, such as ST578 or ST23. Spain is among the European countries with the highest incidences of reported legionellosis cases, and specifically, Comunitat Valenciana (CV) is the second most affected area in the country. In this work, we aimed at studying the overall diversity of
Legionella pneumophila
populations found in the period from 1998 to 2013 in 79 localities encompassing 23 regions within CV. To do so, we performed sequence-based typing (SBT) on 1,088
L. pneumophila
strains detected in the area from both environmental and clinical sources. A comparison with the genetic structuring detected in a global data set that included 20 European and 7 non-European countries was performed. Our results reveal a level of diversity in CV that can be considered representative of the diversity found in other countries worldwide.
Nitrogen Cycling Potential of a Grassland Litter Microbial Community
Authors: Nelson Michaeline B. , Berlemont Renaud , Martiny Adam C. , Martiny Jennifer B. H. 
Published: August 2015

ABSTRACT

Because microorganisms have different abilities to utilize nitrogen (N) through various assimilatory and dissimilatory pathways, microbial composition and diversity likely influence N cycling in an ecosystem. Terrestrial plant litter decomposition is often limited by N availability; however, little is known about the microorganisms involved in litter N cycling. In this study, we used metagenomics to characterize the potential N utilization of microbial communities in grassland plant litter. The frequencies of sequences associated with eight N cycling pathways differed by several orders of magnitude. Within a pathway, the distributions of these sequences among bacterial orders differed greatly. Many orders within the
Actinobacteria
and
Proteobacteria
appeared to be N cycling generalists, carrying genes from most (five or six) of the pathways. In contrast, orders from the
Bacteroidetes
were more specialized and carried genes for fewer (two or three) pathways. We also investigated how the abundance and composition of microbial N cycling genes differed over time and in response to two global change manipulations (drought and N addition). For many pathways, the abundance and composition of N cycling taxa differed over time, apparently reflecting precipitation patterns. In contrast to temporal variability, simulated global change had minor effects on N cycling potential. Overall, this study provides a blueprint for the genetic potential of N cycle processes in plant litter and a baseline for comparisons to other ecosystems.
ERG2
and
ERG24
Are Required for Normal Vacuolar Physiology as Well as Candida albicans Pathogenicity in a Murine Model of Disseminated but Not Vaginal Candidiasis
Authors: Luna-Tapia Arturo , Peters Brian M. , Eberle Karen E. , Kerns Morgan E. , Foster Timothy P. , Marrero Luis , Noverr Mairi C. , Fidel Paul L. , Palmer Glen E. 
Published: August 2015

ABSTRACT

Several important classes of antifungal agents, including the azoles, act by blocking ergosterol biosynthesis. It was recently reported that the azoles cause massive disruption of the fungal vacuole in the prevalent human pathogen
Candida albicans
. This is significant because normal vacuolar function is required to support
C. albicans
pathogenicity. This study examined the impact of the morpholine antifungals, which inhibit later steps of ergosterol biosynthesis, on
C. albicans
vacuolar integrity. It was found that overexpression of either the
ERG2
or
ERG24
gene, encoding C-8 sterol isomerase or C-14 sterol reductase, respectively, suppressed
C. albicans
sensitivity to the morpholines. In addition, both
erg2Δ/Δ
and
erg24Δ/Δ
mutants were hypersensitive to the morpholines. These data are consistent with the antifungal activity of the morpholines depending upon the simultaneous inhibition of both Erg2p and Erg24p. The vacuoles within both
erg2Δ/Δ
and
erg24Δ/Δ
C. albicans
strains exhibited an aberrant morphology and accumulated large quantities of the weak base quinacrine, indicating enhanced vacuolar acidification compared with that of control strains. Both
erg
mutants exhibited significant defects in polarized hyphal growth and were avirulent in a mouse model of disseminated candidiasis. Surprisingly, in a mouse model of vaginal candidiasis, both mutants colonized mice at high levels and induced a pathogenic response similar to that with the controls. Thus, while targeting Erg2p or Erg24p alone could provide a potentially efficacious therapy for disseminated candidiasis, it may not be an effective strategy to treat vaginal infections. The potential value of drugs targeting these enzymes as adjunctive therapies is discussed.
Evaluating the effectiveness of care integration strategies in different healthcare systems in Latin America: the EQUITY-LA II quasi-experimental study protocol
Authors: Vázquez María-Luisa , Vargas Ingrid , Unger Jean-Pierre , De Paepe Pierre , Mogollón-Pérez Amparo Susana , Samico Isabella , Albuquerque Paulette , Eguiguren Pamela , Cisneros Angelica Ivonne , Rovere Mario , Bertolotto Fernando 
Published: August 2015

IntroductionAlthough fragmentation in the provision of healthcare is considered an important obstacle to effective care, there is scant evidence on best practices in care coordination in Latin America. The aim is to evaluate the effectiveness of a participatory shared care strategy in improving coordination across care levels and related care quality, in health services networks in six different healthcare systems of Latin America.Methods and analysisA controlled before and after quasi-experimental study taking a participatory action research approach. In each country, two comparable healthcare networks were selected—intervention and control. The study contains four phases: (1) A baseline study to establish network performance in care coordination and continuity across care levels, using (A) qualitative methods: semi-structured interviews and focus groups with a criterion sample of health managers, professionals and users; and (B) quantitative methods: two questionnaire surveys with samples of 174 primary and secondary care physicians and 392 users with chronic conditions per network. Sample size was calculated to detect a proportion difference of 15% and 10%, before and after intervention (α=0.05; β=0.2 in a two-sided test); (2) a bottom-up participatory design and implementation of shared care strategies involving micro-level care coordination interventions to improve the adequacy of patient referral and information transfer. Strategies are selected through a participatory process by the local steering committee (local policymakers, health care network professionals, managers, users and researchers), supported by appropriate training; (3) Evaluation of the effectiveness of interventions by measuring changes in levels of care coordination and continuity 18 months after implementation, applying the same design as in the baseline study; (4) Cross-country comparative analysis.Ethics and disseminationThis study complies with international and national legal stipulations on ethics. Conditions of the study procedure were approved by each country's ethical committee. A variety of dissemination activities are implemented addressing the main stakeholders. Registration No.257 Clinical Research Register of the Santa Fe Health Department, Argentina.
Factors associated with induced abortion among female entertainment workers: a cross-sectional study in Cambodia
Authors: Yi Siyan , Tuot Sovannary , Chhoun Pheak , Pal Khuondyla , Tith Khimuy , Brody Carinne 
Published: August 2015

ObjectiveTo explore risk factors associated with induced abortion among sexually active female entertainment workers (FEWs) in Cambodia.DesignCross-sectional study.SettingPhnom Penh and Siem Reap, Cambodia.ParticipantsThis study included 556 FEWs aged 18–47 years randomly selected from entertainment establishments in the two cities in 2014 using a two-stage cluster sampling method. Data were collected through face-to-face interviews using a structured questionnaire.Primary outcome measureHistory of induced abortion during the time working as a FEW.ResultsOf the total sample, 45.6% reported currently using a contraceptive method with condom (42.4%) being the most common method, followed by pills (25.6%). One-fourth (25%) of the respondents reported having been pregnant at least once, and 21.4% reported having at least one induced abortion during the time working as a FEW. After controlling for other covariates in a multivariate logistic regression model, FEWs with a history of induced abortion remained significantly more likely to be currently working in a karaoke bar (AOR=1.75, 95% CI 1.10 to 2.78), to have worked longer as a FEW (AOR=1.42, 95% CI 1.06 to 1.43), to have had a greater number of sexual partners in the past 12 months (AOR=1.86, 95% CI 1.02 to 1.54), to be currently using a contraceptive method (AOR=1.52, 95% CI 1.01 to 2.29), to be able to find condoms when they needed them (AOR=2.03, 95% CI 1.09 to 3.82), and to report inconsistent condom use with non-commercial partners in the past 3 months (AOR=1.62, 95% CI 1.06 to 3.44).ConclusionsThis study highlights the high rates of unwanted pregnancies that ended in induced abortions among FEWs in Cambodia. Access of FEWs to quality sexual and reproductive healthcare services is deemed a high priority. Integrated interventions to improve sexual and reproductive health among these vulnerable women should be tailored to reach the most-at-risk groups.