Plan de negocios para una empresa que fomenta la autoestima de la mujer

Este plan de negocios ofrece servicios a las mujeres logrando exaltar su belleza, apoyado por campañas publicitarias sin vulnerar su integridad, brindando asesoría para que logren sentirse armoniosas sin necesidad de cambiar su cuerpo y comportamiento.This business plan will provide services to women obtaining exalt its beauty, supported by advertising campaigns without violating their integrity, providing advice to achieve harmonious feel no need to change your body and behavior.Administrador (a) de EmpresasPregrad

Listeriaphages and coagulin C23 act synergistically to kill Listeria monocytogenes in milk under refrigeration conditions

Bacteriophages and bacteriocins are promising biocontrol tools in food. In this work, two Listeria bacteriophages, FWLLm1 and FWLLm3, were assessed in combination with the bacteriocin coagulin C23 to inhibit Listeria monocytogenes. Preliminary results under laboratory conditions demonstrated that both antimicrobials act synergistically when they were applied in suboptimal concentrations. The combined approach was further assessed in milk contaminated with 5 × 104 CFU/ml L. monocytogenes 2000/47 and stored at 4 °C for 10 days. When used alone, phage FWLLm1 added at 5 × 106 PFU/ml, FWLLm3 at 5 × 105 PFU/ml and coagulin C23 at 584 AU/ml kept L. monocytogenes 2000/47 counts lower than the untreated control throughout storage. However, when used in combination, inhibition was enhanced and in the presence of FWLLm1 and coagulin C23, L. monocytogenes 2000/47 counts were under the detection limits (less than 10 CFU/ml) from day 4 until the end of the experiment. Resistant mutants towards phages and coagulin C23 could be obtained, but cross-resistance was not detected. Mutants resistant to FWLLm3 and coagulin C23 were also recovered from surviving colonies after cold storage in milk which may explain the failure of this combination to inhibit L. monocytogenes. Remarkably, the fraction of resistant mutants isolated from the combined treatment was lower than that from each antimicrobial alone, suggesting that synergy between bacteriocins and phages could be due to a lower rate of resistance development and the absence of cross-resistance

Bacteriophages of Shiga toxin-producing Escherichia coli and their contribution to pathogenicity

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-transcribed together with the late phase genes of the prophages. After being assembled in the cytoplasm, and after host cell lysis, mature bacteriophage particles are released into the environment, together with Stx. As members of the group of lambdoid phages, Stx phages share many genetic features with the archetypical temperate phage Lambda, but are heterogeneous in their DNA sequences due to frequent recombination events. In addition to Stx phages, the genome of pathogenic STEC bacteria may contain numerous prophages, which are either cryptic or functional. These prophages may carry foreign genes, some of them related to virulence, besides those necessary for the phage life cycle. Since the production of one or more Stx is considered the major pathogenicity factor of STEC, we aim to highlight the new insights on the contribution of Stx phages and other STEC phages to pathogenicity

Bacteriophages as fecal pollution indicators

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 (coliphages), have been proposed as alternatives or complements to fecal indicator bacteria. Here, we provide a general overview of the potential use of enteric bacteriophages as fecal and viral indicators in different environments, as well as the available methods for their detection and enumeration, and the regulations for their application

Bacteriophages as weapons against bacterial biofilms in the food industry

Microbiological contamination in the food industry is often attributed to the presence of biofilms in processing plants. Bacterial biofilms are complex communities of bacteria attached to a surface and surrounded by an extracellular polymeric material. Their extreme resistance to cleaning and disinfecting processes is related to a unique organization, which implies a differential bacterial growth and gene expression inside the biofilm. The impact of biofilms on health, and the economic consequences, has promoted the development of different approaches to control or remove biofilm formation. Recently, successful results in phage therapy have boosted new research in bacteriophages and phage lytic proteins for biofilm eradication. In this regard, this review examines the environmental factors that determine biofilm development in food-processing equipment. In addition, future perspectives for the use of bacteriophage-derived tools as disinfectants are discussed

From endolysins to Artilysin ® s: novel enzyme-based approaches to kill drug-resistant bacteria

Abstract One of the last untapped reservoirs in nature for the identification of new anti-microbials is bacteriophages, the natural killers of bacteria. Lytic bacteriophages encode peptidoglycan (PG) lytic enzymes able to degrade the PG layer in different steps of their infection cycle. Endolysins degrade the bacterial cell wall at the end of the infection cycle, causing lysis of the host to release the viral progeny. Recombinant endolysins have been successfully applied as anti-bacterial agent against antibiotic-resistant Gram-positive pathogens. This has boosted the study of these enzymes as new anti-microbials in different fields (e.g. medical, food technology). A key example is the recent development of endolysin-based anti-bacterials against Gramnegative pathogens in which the exogenous application of endolysins is hindered by the outer membrane (OM). These novel anti-microbials, termed Artilysin ® s, are able to pass through the OM and reach the PG where they exert their action. In addition, mycobacteria whose cell wall is structurally different from both Gram-positive and Gram-negative bacteria have also been reported to be inhibited by mycobacteriophageencoded endolysins. Endolysins and endolysin-based anti-microbials can be considered as ideal candidates for an alternative to antibiotics for several reasons: (1) their unique mode of action and activity against bacterial persisters (independent of an active host metabolism), (2) their selective activity against both Gram-positive and Gram-negative pathogens (including antibiotic resistant strains) and mycobacteria, (3) the limited resistance development reported so far. The present review summarizes and discusses the potential applications of endolysins as new anti-microbials

DUF3380 domain from a Salmonella phage endolysin shows potent N -acetylmuramidase activity

Bacteriophage-encoded endolysins are highly diverse enzymes that cleave the bacterial peptidoglycan layer. Current research focuses on their potential applications in medicine, in food conservation, and as biotechnological tools. Despite the wealth of applications relying on the use of endolysin, little is known about the enzymatic properties of these enzymes, especially in the case of endolysins of bacteriophages infecting Gram-negative species. Automated genome annotations therefore remain to be confirmed. Here, we report the biochemical analysis and cleavage site determination of a novel Salmonella bacteriophage endolysin, Gp110, which comprises an uncharacterized domain of unknown function (DUF3380; pfam11860) in its C terminus and shows a higher specific activity (34,240 U/μM) than that of 14 previously characterized endolysins active against peptidoglycan from Gram-negative bacteria (corresponding to 1.7- to 364-fold higher activity). Gp110 is a modular endolysin with an optimal pH of enzymatic activity of pH 8 and elevated thermal resistance. Reverse-phase high-performance liquid chromatography (RP-HPLC) analysis coupled to mass spectrometry showed that DUF3380 has N-acetylmuramidase (lysozyme) activity cleaving the β-(1,4) glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine residues. Gp110 is active against directly cross-linked peptidoglycans with various peptide stem compositions, making it an attractive enzyme for developing novel antimicrobial agents

Is Genetic Mobilization Considered When Using Bacteriophages in Antimicrobial Therapy?

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 antibiotics, although there are still some concerns and legal issues to overcome before it can be implemented on a large scale. Here we highlight some of those concerns, especially those related to the ability of bacteriophages to transport bacterial DNA and, in particular, antibiotic resistance genes

Dominance of phage particles carrying antibiotic resistance genes in the viromes of retail food sources

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 increasing research. However, it has been argued that in these studies the abundance of phages carrying ARGs has been overestimated due to experimental contamination with non-packaged bacterial DNA or other elements such as outer membrane vesicles (OMVs). This study aims to shed light on the extent to which phages, OMVs or contaminating non-packaged DNA contribute as carriers of ARGs in the viromes. The viral fractions of three types of food (chicken, fish, and mussels) were selected as sources of ARG-carrying phage particles, whose ability to infect and propagate in an Escherichia coli host was confirmed after isolation. The ARG-containing fraction was further purified by CsCl density gradient centrifugation and, after removal of DNA outside the capsids, ARGs inside the particles were confirmed. The purified fraction was stained with SYBR Gold, which allowed the visualization of phage capsids attached to and infecting E. coli cells. Phages with Myoviridae and Siphoviridae morphology were observed by electron microscopy. The proteins in the purified fraction belonged predominantly to phages (71.8% in fish, 52.9% in mussels, 78.7% in chicken sample 1, and 64.1% in chicken sample 2), mainly corresponding to tail, capsid, and other structural proteins, whereas membrane proteins, expected to be abundant if OMVs were present, accounted for only 3.8–21.4% of the protein content. The predominance of phage particles in the viromes supports the reliability of the protocols used in this study and in recent findings on the abundance of ARG-carrying phage particles.This work was supported by the Spanish Ministerio de Ciencia e Innovación (PID2020-113355GB-I00), the Agencia Estatal de Investigación (AEI) and the European regional fund (ERF). The study was partially supported by the Generalitat de Catalunya (2017SGR170). PB-P has a grant from the Spanish Ministry of Economy, Industry and Competitiveness (BES-2017-081296), SM-C has a grant from Colciencias (Republic of Colombia) and LR-R is lecturer of the Serra-Hunter program, Generalitat de Catalunya. MDR-B has a Margarita Salas fellowship from the Spanish Ministerio de Universidades

Infectious phage particles packaging antibiotic resistance genes found in meat products and chicken feces

This work was supported by the Spanish Ministerio de Innovación y Ciencia (AGL2016-75536-P), the Agencia Estatal de Investigación (AEI) and the European regional fund (ERF), the Generalitat de Catalunya (2017SGR170) and the Centre de Referència en Biotecnologia (XeRBa). CERCA Programme from the Generalitat de Catalunya is also acknowledged. M.B.-J. has a grant from COLCIENCIAS (Republic of Colombia). P.B.-P. has a grant from the Spanish Ministry of Economy, Industry and Competitiveness (BES-2017-081296). L.R.-R. is supported by the Beatriu de Pinos postdoctoral programme of the Government of Catalonia's Secretariat for Universities and Research of the Ministry of Economy and Knowledge.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 (bla, bla, bla, bla, bla, qnrA, qnrS, mecA, armA and sul1) were analyzed by qPCR in the phage DNA fraction. The genes were quantified, before and after propagation experiments in Escherichia coli, to evaluate the ability of ARG-carrying phage particles to infect and propagate in a bacterial host. According to microbiological parameters, all samples were acceptable for consumption. ARGs were detected in most of the samples after particle propagation indicating that at least part of the isolated phage particles were infectious, being sul1the most abundant ARG in all the matrices followed by β-lactamase genes. ARGs were also found in the phage DNA fraction of thirty-seven archive chicken cecal samples, confirming chicken fecal microbiota as an important ARG reservoir and the plausible origin of the particles found in meat. Phages are vehicles for gene transmission in meat that should not be underestimated as a risk factor in the global crisis of antibiotic resistance