Long-term and short-term variations of Escherichia coli population structure in tropical coastal waters

ABSTRACTAn increasing number of outbreaks of gastroenteritis recently caused byEscherichia coliO157:H7 have been linked to the consumption of leafy green vegetables. Although it is known thatE. colisurvives and grows in the phyllosphere of lettuce plants, the molecular mechanisms by which this bacterium associates with plants are largely unknown. The goal of this study was to identifyE. coligenes relevant to its interaction, survival, or attachment to lettuce leaf surfaces, comparingE. coliK-12, a model system, andE. coliO157:H7, a pathogen associated with a large number of outbreaks. Using microarrays, we found that upon interaction with intact leaves, 10.1% and 8.7% of the 3,798 shared genes were differentially expressed in K-12 and O157:H7, respectively, whereas 3.1% changed transcript levels in both. The largest group of genes downregulated consisted of those involved in energy metabolism, includingtnaA(33-fold change), encoding a tryptophanase that converts tryptophan into indole. Genes involved in biofilm modulation (bhsAandybiM) and curli production (csgAandcsgB) were significantly upregulated inE. coliK-12 and O157:H7. BothcsgAandbhsA(ycfR) mutants were impaired in the long-term colonization of the leaf surface, but onlycsgAmutants had diminished ability in short-term attachment experiments. Our data suggested that the interaction ofE. coliK-12 and O157:H7 with undamaged lettuce leaves likely is initiated via attachment to the leaf surface using curli fibers, a downward shift in their metabolism, and the suppression of biofilm formation.

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Escherichia coli robustly expresses ATP synthase at growth rate maximizing concentrations

10.1101/2021.02.17.431610 ◽

2021 ◽

Author(s):

Iraes Rabbers ◽

Frank J Bruggeman

Keyword(s):

Escherichia Coli ◽

Growth Rate ◽

Protein Expression ◽

Genetic Variants ◽

Evolutionary Adaptation ◽

Wild Type ◽

Short Term ◽

E Coli ◽

Fitness Maximization

AbstractImproved protein expression is an important evolutionary adaptation of bacteria. A key question is whether evolution has led to optimal protein expression that maximizes immediate growth rate (short-term fitness) across conditions. Alternatively, fitter genetic variants could display suboptimal short-term fitness, because they cannot do better or because they strive for long-term fitness maximization by, for instance, anticipating future conditions. To answer this question, we focus on the ATP-producing enzyme F1F0 H+-ATPase, which is an abundant enzyme and ubiquitously expressed across conditions. We tested the optimality of H+-ATPase expression in Escherichia coli across 27 different nutrient conditions. In all tested conditions, wild-type E. coli expresses its H+- ATPase remarkably close to optimal concentrations that maximize immediate growth rate. This work indicates that bacteria can achieve robust optimal protein expression for immediate growth- rate.

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DURATION OF NEOMYCIN THERAPY FOR ENTEROPATHOGENIC ESCHERICHIA COLI DIARRHEAL DISEASE: A COMPARATIVE STUDY OF 113 CASES

PEDIATRICS ◽

10.1542/peds.48.2.248 ◽

1971 ◽

Vol 48 (2) ◽

pp. 248-258

Author(s):

John D. Nelson

Keyword(s):

Escherichia Coli ◽

Diarrheal Disease ◽

Fluorescent Antibody ◽

Infectious Complications ◽

Term Therapy ◽

Enteropathogenic Escherichia Coli ◽

Short Term ◽

Short Term Therapy

The usually recommended 7- to 10- day course of antibiotic therapy for enteropathogenic Escherichia coli diarrheal disease might be undesirable because neomycin can cause a malabsorption syndrome. One hundred thirteen infants with E. coli arrheal disease were randomly assigned to long-term therapy of 10 days or to short-term therapy. For short-term therapy neomycin was discontinued when daily fluorescent antibody and culture tests were negative; therapy averaged 3 days with a range of 2 to 4½ days for all but one patient. The pathogens were susceptible to neomycin in vitro. The initial bacteriologic response was the same in both groups. Bacteriologic relapse without return of symptoms occurred in 14 of 57 in the longterm group and in 7 of 56 babies in the short-term group. Organisms isolated during relapse remained sensitive in vitro to neomycin. In the long-term group diarrhea lasted significanfly longer with a trend to delayed onset of steady weight gain and infectious complications were twice as common. There was no significant change in indirect hemagglutinin titer between acute and convalescent sera in 91% of specimens. Current recommendations for duration of therapy should be shortened to 3 to 5 days. This study and a literature review also raise doubts about the real value of antibiotics in this disease.

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Extraintestinal pathogenic (ExPEC) lineages explain prolonged carriage of travel-acquired extended-spectrum β-lactamase-producing Escherichia coli

10.1101/2020.09.23.309856 ◽

2020 ◽

Author(s):

Boas C.L. van der Putten ◽

Jarne M. van Hattem ◽

John Penders ◽

Daniel R. Mende ◽

Constance Schultsz ◽

...

Keyword(s):

Escherichia Coli ◽

Prospective Cohort ◽

International Travel ◽

Short Term ◽

E Coli ◽

Extended Spectrum ◽

Long Read ◽

World Tourism Organization ◽

Public Datasets

AbstractFecally carried extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-Ec) are frequently acquired during international travel, contributing to global spread of AMR. However, determinants of long-term carriage of travel-acquired ESBL-Ec are unknown.From a prospective cohort study of 2001 international travelers, we selected all 28 who acquired ESBL-Ec during travel and subsequently carried ESBL-Ec for at least 12 months after return. We sequenced a total of 155 ESBL-Ec isolates from these long-term carriers and 54 age-, sex- and destination-matched short-term carriers (<1 month carriage). We confirmed persistence of ESBL-Ec in long-term carriers using SNP typing and compared ESBL-Ec from long-term and short-term carriers using in silico multi-locus sequence and phylogroup typing. We employed long-read sequencing to investigate ESBL plasmid dissemination.We show that extraintestinal pathogenic (ExPEC) lineages of Escherichia coli are significantly more likely to persist in healthy travelers than other E. coli lineages, in the absence of antibiotic usage, mainly driven by sequence type (ST) 131 and phylogroup D E. coli. Additionally, we identified two epidemiologically unrelated clonal lineages of ST38 carrying a range of ESBL- and carbapenemase-encoding genes. Using public datasets, we demonstrate the recent parallel emergence of these lineages and their subsequent rapid global dissemination, which has major implications for epidemiological tracking of ST38 strains.Our findings show that persistence of travel-acquired ESBL-Ec is mediated by a limited number of ExPEC lineages. These findings support recent insights suggesting ExPEC lineages have not necessarily evolved towards virulence, but rather towards efficient intestinal colonization.ImportanceIn 2018, an estimated 1.4 billion international trips were undertaken according to the World Tourism Organization. Antibiotic resistant Escherichia coli are frequently acquired during travel due to contact with contaminated foodstuff, or fecal-oral, environmental and human-to-human transmission. Resistant E. coli that can persist in the travelers’ gut for long periods of time after return from travel, are likely to contribute to further transmission. Using highly detailed genomic typing of resistant E. coli, isolated from a large prospective cohort of international travelers, we identified bacterial characteristics explaining long-term carriage. Our results provide important information that can be used to estimate the risk of long-term carriage when travelers return with acquired resistant E. coli.

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PHENOTYPIC CHARACTERIZATION OF ESCHERICHIA COLI ISOLATED FROM URINE AND STOOL FROM SHORT TERM AND LONG TERM CATHETERIZED PATIENTS

Eastern Journal of Medical Sciences ◽

10.32677/ejms.2016.v01.i01.005 ◽

2016 ◽

Vol 1 (1) ◽

pp. 17-23

Author(s):

Kamalakar Sarva ◽

Gomathi Chitra ◽

Jharna Mandal ◽

Manikandan R

Keyword(s):

Escherichia Coli ◽

Phenotypic Characterization ◽

Short Term

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Global gene expression in Escherichia coli K-12 during short-term and long-term adaptation to glucose-limited continuous culture conditions

Microbiology ◽

10.1099/mic.0.28939-0 ◽

2006 ◽

Vol 152 (7) ◽

pp. 2111-2127 ◽

Cited By ~ 80

Author(s):

Alessandro G. Franchini ◽

Thomas Egli

Keyword(s):

Escherichia Coli ◽

Continuous Culture ◽

Transcriptome Analysis ◽

Glyoxylate Cycle ◽

Carbon Sources ◽

Culture Conditions ◽

Mrna Levels ◽

Short Term ◽

K 12

Microarray technology was used to study the cellular events that take place at the transcription level during short-term (physiological) and long-term (genetic) adaptation of the faecal indicator bacterium Escherichia coli K-12 to slow growth under limited nutrient supply. Short-term and long-term adaptation were assessed by comparing the mRNA levels isolated after 40 or 500 h of glucose-limited continuous culture at a dilution rate of 0.3 h−1 with those from batch culture with glucose excess. A large number of genes encoding periplasmic binding proteins were upregulated, indicating that the cells are prepared for high-affinity uptake of all types of carbon sources during glucose-limited growth in continuous culture. All the genes belonging to the maltose (mal/lamB) and galactose (mgl/gal) operons were upregulated. A similar transcription pattern was observed for long-term cultures except that the expression factors were lower than in the short-term adaptation. The patterns of upregulation were confirmed by real-time RT-PCR. A switch from a fully operational citric acid cycle to the PEP-glyoxylate cycle was clearly observed in cells grown in glucose-limited continuous culture when compared to batch-grown cells and this was confirmed by transcriptome analysis. This transcriptome analysis confirms and extends the observations from previous proteome and catabolome studies in the authors' laboratory.

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The support of multidimensional approaches in integrate monitoring for SEA: a case of study

Earth System Dynamics Discussions ◽

10.5194/esdd-3-1191-2012 ◽

2012 ◽

Vol 3 (2) ◽

pp. 1191-1220

Author(s):

C. M. Torre ◽

M. Selicato

Keyword(s):

Spatial Data ◽

Carrying Capacity ◽

Coastal Waters ◽

Coastal Erosion ◽

Strategic Environmental Assessment ◽

Human Pressure ◽

Short Term ◽

Urban Settlements ◽

Definition Of

Abstract. During centuries, seaside has represented a crucial pole for future human development and civilization. The use of the sea for transport and trade and the overwhelming availability of food derived from coastal waters have encouraged and strengthened the growth of urban settlements. In the same time, the human pressure menaces to destroy coastal habitats, and consequently their carrying capacity that permits to guest many essential functions. Low-impact activities are often replaced on the surface by new intensive others that are attractive in the short term, but that in the long term undermine of reducing the resilience of the coast. It is clear that, in a perspective of sustainable development, economically efficient and socially equitable use of coastal areas need to be supported inside strategies to correct these weaknesses. The definition of such strategies and their implementation in the Strategic Environmental Assessment (SEA) is an essential tool of decision support and of monitoring. The issues of monitoring, more in particular, have been subject of study and modeling by the use of Dynamic Spatial Data Analisys (DSDA), in the case of the SEA of the Coastal Plan of the Italian Apulia Region, as an information instrument for regulating the anthropogenic changes; a possibility to implement the analysis of environmental sensitivity and propensity to Coastal erosion has been explored, in order to control the level of human pressure on land. The monitoring system should provide an automatic "alert" when the dimension and the velocity of change of land use overpass some threshold of environmental pressure.

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The study of chromosomal inversion polymorphism of Drosophila subobscura over years in two different habitats from mountain Goc

Genetika ◽

10.2298/gensr0702155a ◽

2007 ◽

Vol 39 (2) ◽

pp. 155-167 ◽

Cited By ~ 4

Author(s):

Marko Andjelkovic ◽

Marina Stamenkovic-Radak ◽

Zorana Kurbalija ◽

Bojan Kenig ◽

Gordana Rasic ◽

...

Keyword(s):

Population Structure ◽

Sex Chromosome ◽

Drosophila Subobscura ◽

Inversion Polymorphism ◽

Global Changes ◽

Short Term ◽

Oak Wood ◽

Significant Difference ◽

First Time

We analyzed changes in the genetic structure of two ecologically distinct populations of Drosophila subobscura by assessing inversion polymorphism parameters for over years. The frequencies of gene arrangements on all five chromosomes show variability in each population. Several chromosomal arrangements appeared for the first time in both populations. Significant difference in the overall distribution of gene arrangements between first and last year of study (1998/2006) in beach wood population of D. subobscura is found for chromosome A (a sex chromosome) and autosomes J and E, while in oak wood population the overall frequency of gene arrangements differ for autosomes J, E and O. The present significant changes of the particular gene arrangements are specific for each population and result in significant differences in comparisons at the level of individual chromosomes between years of study. Although overall heterozygosity remained unchanged over the years in beech habitat, it is significantly reduced in oak population in the fourth year. The obtained results indicate that population structure may significantly depend on short-term and long-term microclimatic changes in habitats. Based on the results to date, monitoring of microevolutionary changes using D. subobscura and its relatives seems a promising way to study the effects of global changes. .

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The support of multidimensional approaches in integrate monitoring for SEA: a case of study

Earth System Dynamics ◽

10.5194/esd-4-51-2013 ◽

2013 ◽

Vol 4 (1) ◽

pp. 51-61 ◽

Cited By ~ 4

Author(s):

C. M. Torre ◽

M. Selicato

Keyword(s):

Spatial Data ◽

Carrying Capacity ◽

Coastal Waters ◽

Spatial Data Analysis ◽

Human Pressure ◽

Short Term ◽

Urban Settlements ◽

The Subject ◽

Definition Of

Abstract. During the centuries, the seaside has represented a crucial pole for future human development and civilization. The use of the sea for transport and trade and the overwhelming availability of food derived from coastal waters have encouraged and strengthened the growth of urban settlements. In the same time, the human pressure menaces to destroy coastal habitats and consequently their carrying capacity that allows for many essential functions. Low-impact activities are often replaced, on the surface, by new intensive ones that are attractive in the short term, but that in the long term undermine by reducing the resilience of the coast. It is clear that, in a perspective of sustainable development, economically efficient and socially equitable use of coastal areas need to be supported inside strategies to correct these weaknesses. The definition of such strategies and their implementation in the Strategic Environmental Assessment (SEA) is an essential tool for supporting decisions and of monitoring. The issues of monitoring, more in particular, have been the subject of study and modelling by the use of Dynamic Spatial Data Analysis (DSDA), in the case of the SEA of the Coastal Plan of the Italian Apulia Region, as an information instrument for regulating the anthropogenic changes; a possibility to implement the analysis of environmental sensitivity and propensity to Coastal erosion has been explored, in order to control the level of human pressure on land. The monitoring system should provide an automatic "alert" when the dimension and the velocity of the change of land use overpass some threshold of environmental pressure.

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Viability and stability ofEscherichiacoliand enterococci populations in fecal samples upon freezing

Canadian Journal of Microbiology ◽

10.1139/cjm-2015-0020 ◽

2015 ◽

Vol 61 (7) ◽

pp. 495-501 ◽

Cited By ~ 6

Author(s):

N. Masters ◽

M. Christie ◽

H. Stratton ◽

M. Katouli

Keyword(s):

Escherichia Coli ◽

Population Structure ◽

Host Species ◽

Bacterial Species ◽

Short Term ◽

Fecal Samples ◽

E Coli ◽

Short Term Storage ◽

Before And After ◽

Term Storage

We studied the survival of Escherichia coli and enterococci populations in fecal samples of 7 host species after storage at –20 and –80 °C for 30 days. Composite fecal samples were collected from cows, chickens, horses, pigs, dogs, birds, and humans, and bacteria were enumerated before and after storage. Twenty-eight colonies of each bacterial species were typed before and after storage and the strains were assigned to different biochemical phenotypes (BPTs). A significant reduction in the number of E. coli was observed in all samples stored at –20 °C but in only 3 of those samples stored at –80 °C. However, the numbers of enterococci were similar in most stored samples (except cow and birds). The number and the distribution of E. coli and enterococci BPTs in fresh samples did not vary significantly from those stored at either temperature. Furthermore, the population structure of E. coli and enterococci did not change significantly after storage at –80 °C, this was always the case for those samples stored at –20 °C. We conclude that for those studies investigating E. coli or enterococci population structure, short-term storage (≤30 days) of fecal samples in a glycerol broth at –80 °C is a preferable option.

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