Maite Muniesa

Maite Muniesa
University of Barcelona | UB · Department of Genetics, Microbiology and Statistics

Professor of Microbiology

About

189
Publications
32,069
Reads
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6,578
Citations
Citations since 2016
65 Research Items
3962 Citations
20162017201820192020202120220200400600
20162017201820192020202120220200400600
20162017201820192020202120220200400600
20162017201820192020202120220200400600
Additional affiliations
December 2003 - April 2017
University of Barcelona
Position
  • Professor
September 2000 - present
Universitat de Barcelona
September 1999 - August 2000
Institut fur medizinische mikrobiologie
Position
  • University of Giessen

Publications

Publications (189)
Article
Full-text available
The growth of antibiotic resistance has stimulated interest in understanding the mechanisms by which antibiotic resistance genes (ARG) are mobilized. Among them, studies analyzing the presence of ARGs in the viral fraction of environmental, food and human samples, and reporting bacteriophages as vehicles of ARG transmission, have been the focus of...
Article
Antibiotic resistance genes (ARGs) have been identified in viral DNA isolated from different kinds of food, but little is known about their origin. In this study, twenty-one viromes were analyzed from samples of food previously reported to carry ARGs, including meat (poultry, veal, and pork), fish (Mediterranean, Atlantic, frozen, farmed and shellf...
Article
Full-text available
Poultry meat production is one of the most important agri‐food industries in the world. The selective pressure exerted by widespread prophylactic or therapeutic use of antibiotics in intensive chicken farming favours the development of drug resistance in bacterial populations. Chicken liver, closely connected with the intestinal tract, has been dir...
Article
Full-text available
Antibiotic resistance is one of the major challenges that humankind shall face in the short term. (Bacterio)phage therapy is a valuable therapeutic alternative to antibiotics and, although the concept is almost as old as the discovery of phages, its wide application was hindered in the West by the discovery and development of antibiotics in the mid...
Article
Full-text available
The raw sewage that flows through sewage systems contains a complex microbial community whose main source is the human gut microbiome, with bacteriophages being as abundant as bacteria or even more so. Phages that infect common strains of the human gut bacteriome and transient bacterial pathogens have been isolated in raw sewage, as have other phag...
Article
Phages, the most abundant biological entities in the biosphere, can carry different bacterial genes, including those conferring antibiotic resistance. In this study, dairy products were analyzed by qPCR for the presence of phages and phage particles containing antibiotic resistance genes (ARGs). Eleven ARGs were identified in 50 samples of kefir, y...
Article
Full-text available
Bacteriophages are promising tools for the detection of fecal pollution in different environments, and particularly for viral pathogen risk assessment. Having similar morphological and biological characteristics, bacteriophages mimic the fate and transport of enteric viruses. Enteric bacteriophages, especially phages infecting Escherichia coli (col...
Article
Full-text available
Aquatic environments are key niches for the emergence, evolution and dissemination of antimicrobial resistance. However, the population diversity and the genetic elements that drive the dynamics of resistant bacteria in different aquatic environments are still largely unknown. The aim of this study was to understand the population genomics and evol...
Article
Full-text available
Shiga toxins (Stx) of Shiga toxin-producing Escherichia coli (STEC) are generally encoded in the genome of lambdoid bacteriophages, which spend the most time of their life cycle integrated as prophages in specific sites of the bacterial chromosome. Upon spontaneous induction or induction by chemical or physical stimuli, the stx genes are co-transcr...
Chapter
Shiga toxin (Stx) phages can be induced from Stx-producing Escherichia coli strains (STEC) or can be isolated as free virions from different samples. Here we describe methods used for the detection, enumeration, and isolation of Stx bacteriophages. Stx phages are temperate phages located in the genome of STEC. Their induction from the host strain c...
Article
Bacteriophages are present in fluids from cirrhosis patients. However, their effect on the immune response is unknown. In this work, we explore the role of phages in the phenotype, function, and cytokine production of monocytes. We stimulated healthy monocytes with five different butanol-purified phage suspensions infective for Gram-negative and Gr...
Article
Full-text available
The genomes of gut Bacteroidales contain numerous invertible regions, many of which contain promoters that dictate phase-variable synthesis of surface molecules such as polysaccharides, fimbriae, and outer surface proteins. Here, we characterize a different type of phase-variable system of Bacteroides fragilis, a Type I restriction modification sys...
Article
Full-text available
Anthropogenic activities are a key factor in the development of antibiotic resistance in bacteria, a growing problem worldwide. Nevertheless, antibiotics and resistances were being generated by bacterial communities long before their discovery by humankind, and might occur in areas without human influence. Bacteriophages are known to play a relevan...
Article
Full-text available
Objectives: To investigate the relevance of multicopy plasmids in antimicrobial resistance and assess their mobilization mediated by phage particles. Methods: Several databases with complete sequences of plasmids and annotated genes were analysed. The 16S methyltransferase gene armA conferring high-level aminoglycoside resistance was used as a m...
Article
Full-text available
Bacteriophages are pivotal elements in the dissemination of virulence genes. The main virulence determinants of Shiga Toxin producing E. coli, Shiga Toxins (Stx), are encoded by genes localized in the genome of lambdoid bacteriophages. Stx comprise two antigenically different types, Stx1 and Stx2, further divided into subtypes. Among these, certain...
Article
F-specific coliphages have been proposed as viral indicators of fecal pollution. These intestinal phages infect cells through the F-pili of the host strains used for their detection, Escherichia coli HS/FAmp in the US-EPA standard method and Salmonella enterica WG49 in the ISO method. The recently designed Bluephage protocol allows the rapid detect...
Chapter
Bacteria and phages have co-existed for several billions of years. The direct observation of their relationship, and the evidence that phages cause bacterial lysis and death, has led researchers to believe that phages and bacteria are natural enemies and that phages can be applied as antimicrobial agents. However, phages are also known to provide v...
Book
Full-text available
This is the first book to systemize all levels of communicative behavior of phages. Phages represent the most diverse inhabitants on this planet. Until today they are completely underestimated in their number, skills and competences and still remain the dark matter of biology. Phages have serious effects on global energy and nutrient cycles. Phages...
Preprint
Full-text available
Background- This study aims to evaluate the efficacy of using a cleansing eyelid wipe to reduce microbial load in healthy subjects. Methods- A single-center, prospective study was conducted. Twenty healthy subjects were assigned to wipe their periocular area (eyelid, eyelashes and lid margin) twice a day with a commercial sterile wipe for 5 consecu...
Article
Full-text available
Enteric bacteriophages (somatic coliphages, F-specific coliphages or both together) are now recognized as useful viral indicators in water, shellfish, and biosolids and are being progressively included in national and international sanitary regulations. Among them, somatic coliphages have an advantage in that they usually outnumber F-RNA coliphages...
Article
Somatic and F-specific coliphages are gaining ground as indicators of fecal/viral pollution. Guidelines and regulations worldwide for monitoring water, biosolids and food are including them as parameters to assess quality and treatment efficiency. Robust methods to detect and quantify both groups of phages in water samples have been launched by age...
Article
Full-text available
Bacteriophages are abundant in human biomes and therefore in human clinical samples. Although this is usually not considered, they might interfere with the recovery of bacterial pathogens at two levels: 1) by propagating in the enrichment cultures used to isolate the infectious agent, causing the lysis of the bacterial host and 2) by the detection...
Article
In this study, the plasmid content of clinical and commensal strains was analysed and compared. The replicon profile was similar in both, except for L, M, A/C and N (detected only in clinical strains) and HI1 (only in commensal strains). Although I1 and F were the most frequent replicons, only IncI1 ST12 was associated with blaCMY-2 in both populat...
Chapter
Here we introduce methods for the detection, enumeration, and isolation of bacteriophages from Escherichia coli. In bacteria, horizontal gene transfer may be mediated by virulent and temperate phages. Strict virulent phages, able to propagate in a suitable strain following the lytic pathway, can be isolated directly from different natural environme...
Article
Full-text available
Microbiomes are vast communities of microorganisms and viruses that populate all natural ecosystems. Viruses have been considered to be the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared with that...
Article
Full-text available
Bacteriophages can package part of their host’s genetic material, including antibiotic resistance genes (ARGs), contributing to a rapid dissemination of resistances among bacteria. Phage particles containing ARGs were evaluated in meat, pork, beef and chicken minced meat, and ham and mortadella, purchased in local retailer. Ten ARGs (blaTEM, blaCTX...
Article
Objectives: Antimicrobial resistance genes (ARGs) can be transferred by means of mobile genetic elements, which play a critical role in the dissemination of resistance in the bacterial community. ARG transmission within mobile genetic elements has been reported in plasmids and transposons but less frequently in bacteriophages. Here, the bacterioph...
Article
Recent studies have shown that crAssphage is abundant in human faecal samples worldwide. It has thus been postulated as a potential microbial source tracking (MST) marker to detect human faecal pollution in water. However, an effective implementation of crAssphage in water management strategies will depend on an understanding of its environmental d...
Preprint
Full-text available
Microbiomes are vast communities of microbes and viruses that populate all natural ecosystems. Viruses have been considered the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared to other environments...
Article
Full-text available
Hemolytic uremic syndrome (HUS), principally caused by shiga toxins (Stxs), is associated with Shiga toxin-producing Escherichia coli (STEC) infections. We previously reported Stx2 expression by host cells in vitro and in vivo. As the genes encoding the two Stx subunits are located in bacteriophage genomes, the aim of the current study was to evalu...
Article
Full-text available
Enterohaemorrhagic Escherichia coli (EHEC) is a major foodborne pathogen responsible for human diseases ranging from diarrhoea to life-threatening complications. Survival of the pathogen and modulation of virulence gene expression along the human gastrointestinal tract (GIT) are key features in bacterial pathogenesis, but remain poorly described, d...
Article
Two groups of coliphages have been recently included in different water management policies as indicators of viral fecal pollution in water and food: somatic coliphages, which infect E. coli through cell wall receptors, and F-specific RNA coliphages, which infect through the F-pili. Somatic coliphages are more abundant in fecally contaminated water...
Article
Full-text available
Shigella sonnei is responsible for the majority of shigellosis infections in the United States with over 500,000 cases reported annually. Here we present the complete genome of the clinical multidrug resistant (MDR) strain 866, which is highly susceptible to bacteriophage infections. The strain has a circular chromosome of 4.85 Mb and carries a 113...
Article
Full-text available
Cystic fibrosis (CF) is a chronic disease in which the bacterial colonization of the lung is linked to an excessive inflammatory response that leads to respiratory failure. The microbiology of CF is complex. Staphylococcus aureus is the first bacterium to colonize the lungs in 30% of pediatric CF patients, and 80% of adult patients develop a chroni...
Article
Bacteriophages are ubiquitously distributed prokaryotic viruses that are more abundant than bacteria. As a consequence of their life cycle, phages can kidnap part of their host's genetic material, including antibiotic resistance genes (ARGs), which released phage particles transfer in a process called transduction. The spread of ARGs among pathogen...
Article
Full-text available
Escherichia coli strain WG5 is a widely used host for phage detection, including somatic coliphages employed as standard ISO method 10705-1 (2000). Here, we present the complete genome sequence of a commercial E. coli WG5 strain.
Chapter
Here we describe the detection, enumeration, and isolation of bacteriophages infecting Bacteroides. The method is based on the infection of Bacteroides host strains and the production of visible plaques in a confluent lawn of the host strain using the double-layer agar method. This is a straightforward methodology that can be applied for the detect...
Article
The emergence of multi-drug resistant bacteria has undermined our capacity to control bacterial infectious diseases. Measures needed to tackle this problem include controlling the spread of antibiotic resistance, designing new antibiotics, and encouraging the use of alternative therapies. Phage therapy seems to be a feasible alternative to antibiot...
Article
Full-text available
A growing interest in healthy eating has lead to an increase in the consumption of vegetables, associated with a rising number of bacterial outbreaks related to fresh produce. This is the case of the outbreak in Germany, caused by a O104:H4 enteroaggregative E. coli strain lysogenic for a Stx phage. Temperate Stx phages released from their hosts oc...
Article
Phage particles have emerged as elements with the potential to mobilize antibiotic resistance genes (ARGs) in different environments, including the intestinal habitat. The aim of this study was to determine the occurrence of ARGs in phage particles present in fecal matter and induced from strains isolated from feces. Nine ARGs (blaTEM, blaCTX-M-1-g...
Article
The use of somatic coliphages as indicators of fecal and viral pollution in water and food has great potential due to the reliability, reproducibility, speed and cost effectiveness of methods for their detection. Indeed, several countries already use this approach in their water management policies. Although standardized protocols for somatic colip...
Article
Full-text available
In recent decades, considerable effort has been devoted to finding microbial source-tracking (MST) markers that are suitable to assess the health risks of faecally polluted waters, with no universal marker reported so far. In this study, the abundance and prevalence of a crAssphage-derived DNA marker in wastewaters of human and animal origins were...
Data
Fig. S1. CrAssphage qPCR assay. Location of primers and probes designed for the end‐point and qPCR assay.
Article
Efforts to identify and characterize strategies for horizontal gene transfer (HGT) in prokaryotes could have overlooked some mechanisms that do not entirely fit in with the canonical ones most often described (conjugation of plasmids, phage transduction and transformation). The difficulty in distinguishing the different HGT strategies could have co...
Article
Full-text available
The increasing resistance to carbapenems is an alarming threat in the fight against multiresistant bacteria. The dissemination properties of antimicrobial resistance genes are supported by their detection in a diverse population of bacteria, including strains isolated from the environment. The objective of this study was to investigate the presence...
Data
List of primers used in this study. (PDF)
Article
Full-text available
Bacteriophages, viruses that infect bacteria, have re-emerged as powerful regulators of bacterial populations in natural ecosystems. Phages invade the human body, just as they do other natural environments, to such an extent that they are the most numerous group in the human virome. This was only revealed in recent metagenomic studies, despite the...
Article
Abstract The spread of antibiotic resistance genes (ARGs) in the environment is a serious concern. Bacterial ARGs can spread via different mobile genetic elements as phage particles, which thereby emerge as novel vectors for environmental dissemination. To assess how climate events, such as heavy rains or water scarcity, could affect the spread of...
Article
Objectives: The mobile colistin resistance gene mcr-1 has been identified worldwide in human and animal sources, while its occurrence in the environment is still largely unknown. The aim of this study was to investigate the presence of mcr-1-harbouring Enterobacteriaceae in water samples obtained from rivers and waste water treatment plants in the...
Chapter
Full-text available
Environmental bacteria harbor antibiotic resistances that are later found in clinical isolates, complicating the treatment of infectious diseases. Since the introduction of antibiotics, the diversity of antibiotic-producing bacteria together with the contribution of mobile elements in the environment, an increasing spread of resistance genes has be...
Article
Full-text available
Bacteriophages are viruses that infect bacteria, and they are found everywhere their bacterial hosts are present, including the human body. To explore the presence of phages in clinical samples, we assessed 65 clinical samples (blood, ascitic fluid, urine, cerebrospinal fluid, and serum). Infectious tailed phages were detected in >45% of ascitic fl...
Article
Full-text available
Here we report the isolation of heat-resistant Escherichia coli from raw milk cheeses. Detection of the heat-resistance markers clpK and orfI by PCR was followed by phenotypical confirmation of increased heat-resistance. These strains were Shiga toxin-negative and, although several were found to be multidrug resistant, no plasmids encoding extended...
Article
Full-text available
The genomes of Gram-negative bacteria encode paralogues and/or orthologues of global modulators. The nucleoid-associated H-NS and Hha proteins are an example: several enterobacteria such as Escherichia coli or Salmonella harbor H-NS, Hha and their corresponding paralogues, StpA and YdgT proteins, respectively. Remarkably, the genome of the pathogen...
Article
Full-text available
Two groups of bacteriophages that infect Escherichia coli, somatic and F-specific coliphages, have been used in academia as both fecal and viral indicators for many years. Regulatory authorities in different parts of the world are beginning to consider coliphages as indicators of water quality in a range of settings. However, issues such as their p...
Article
Abstract The emergence and prevalence of antibiotic resistance genes (ARGs) in the environment is a serious global health concern. ARGs from bacteria can be mobilized by mobile genetic elements, and recent studies indicate that phages and phage-derived particles, among others, could play a role in the spread of ARGs through the environment. ARGs ar...
Article
Full-text available
Bacteroides spp. have been proposed as indicators of fecal contamination in microbial source tracking (MST) methodologies. The aim of this study was to develop new qPCR assays that target host-specific Bacteroidal 16S ribosomal RNA genes, to determine the source of fecal contamination in water. Denaturing gradient gel electrophoresis (DGGE) was use...
Article
Lysogeny by temperate phages provides novel functions for bacteria and shelter for phages. However, under conditions that activate the phage lytic cycle, the benefit of lysogeny becomes a paradox that poses a threat for bacterial population survival. Using Escherichia coli lysogens for Shiga toxin (Stx) phages as model, we demonstrate how lysogenic...
Article
Stx bacteriophages are involved in the pathogenicity of Stx-producing Escherichia coli. Induction of the Stx phage lytic cycle increases Stx expression and releases Stx phages that reach extracellular environments. Stx phage family comprises different phages that harbour any stx subtype. Stx2 is closely related with severe disease and therefore pre...
Article
Infection and lysogenic conversion with Shiga toxin-encoding bacteriophages (Stx phages) drive the emergence of new Shiga toxin-producing Escherichia coli. Phage attachment to the bacterial surface is the first stage of phage infection. Envelope perturbation causes activation of envelope stress responses in bacterial cells. Although many external f...
Article
In this study we use a machine learning software (Ichnaea) to generate predictive models for water samples with different concentrations of fecal contamination (point source, moderate and low). We applied several MST methods (host-specific Bacteroides phages, mitochondrial DNA genetic markers, Bifidobacterium adolescentis and Bifidobacterium dentiu...
Article
Full-text available
Detection of Shiga toxin-producing Escherichia coli (STEC) by culture methods is advisable to identify the pathogen, but recovery of the strain responsible for the disease is not always possible. The use of DNA-based methods (PCR, quantitative PCR [qPCR], or genomics) targeting virulence genes offers fast and robust alternatives. However, detection...