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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Catheter-Associated Urinary Tract Infection in New York and North Carolina

Abiodun, Kehinde O. 01 January 2018 (has links)
In the United States, many hospitalized patients with indwelling urinary catheters acquire catheter-associated urinary tract infections (CAUTI) during their hospital stay. CAUTI negatively affects peoples' health and quality of life and causes a financial burden to individuals and the nation. The purpose of this quantitative cross-sectional study was to explore the relationship between gender, age, and hospital types and CAUTI incidence in New York and North Carolina over a 3-year period. The theoretical framework of choice was the Donabedian model. Simple logistic regression and hierarchical multivariable logistic regression analysis were performed on archival data that was requested from Healthcare Cost and Utilization Project (HCUP) agency. According to the findings, males (n = 61,040) were at a higher risk of developing CAUTI compared to female (n = 66,792) (p < .001) in New York and North Carolina between 2012 and 2014. The odds of getting CAUTI were much higher among age > = 45 compared to the < 17 years. These findings fit in with previous literature identifying age and gender as having a significant relationship with CAUTI occurrence. The outcomes in this study may guide the formulation of policies that are age-appropriate, gender-specific, and facility-tailored to reduce the incidence of CAUTI.
72

Evaluation expérimantale des concentrations critiques de la témocilline vis-à-vis de souches d'entérobactérales. / Experimental evaluation of tenocillin clinical breakpoints against enterobacterales

Alexandre, Kévin 20 September 2019 (has links)
Dans le monde entier l’antibiorésistance des entérobactérales communautaires, notamment par production de ß-lactamase à spectre étendu (E-BLSE), conduit à une consommation préoccupante d’antibiotique de dernier recours tels les carbapénèmes. Dérivé de la ticarcilline la témocilline pourrait représentée une alternative y compris sur certaines entérobactérales productrices de carbapénèmase (EPC). Néanmoins, il existe une incertitude concernant les concentrations critiques distinguant les entérobactérales sensibles des résistantes avec trois valeurs selon les pays utilisateurs de témocilline (8 mg/L, 16 mg/L ou 32 mg/L) tandis qu’une harmonisation internationale reste en attente. En ce contexte trois travaux originaux ont été poursuivi ainsi qu’une revue de la littérature. Il fut d’abord étudié in vitro la sensibilité à la témocilline de 762 entérobactérales responsables d’infection urinaire communautaire. Dans un contexte de prévalence faible des E-BLSE (5%) et nulle des EPC, les trois méthodes de routine (disque, automate, Etest) se sont révélées très fiables, la borne épidémiologique pour la témocilline s’établissant à 8 mg/L. Ensuite, l’efficacité de la témocilline vis-à-vis d’entérobactérales productrices ou non de ßlactamases (E-BLSE ou EPC) a été évaluée dans deux modèles murins complémentaires. Il a été montré l’efficacité de la témocilline à un schéma reproduisant la posologie humaine de 2 g toutes 12 h vis-à-vis d’entérobactérales pour lesquels la CMI de la témocilline était de 8 mg/L. L’efficacité de ce schéma posologique, bien que significative, était moindre vis-à-vis des isolats pour lesquels la CMI de la témocilline était de 16 mg/L. Par contre, il ne fut pas observé d’efficacité significative de la témocilline vis-à-vis des isolats avec une CMI à 32 mg/L quelques soit le schéma posologique (2 g toutes les 8 ou 12 h). L’ensemble de ces résultats, ainsi qu’une revue exhaustive des données de la littérature, conduisent à proposer une concentration critique de 8 mg/L pour le schéma posologique de 2 g toutes les 12 h, et de 16 mg/L pour celui de 2 g toutes les 8h. Cette dernière proposition correspondrait au « sensible à forte exposition », nouvelle définition de la catégorisation « intermédiaire » selon les dernières recommandations de l’EUCAST. / Worldwide spread of antimicrobial resistance among community-acquired enterobacterales, especially ESBL, leads to a worrying consumption of last resort antibiotics like carbapenem. Derivative of ticarcillin, temocillin may be an attractive carbapenem-sparing agent including against some carbapenemase-producing enterobacterales (CPE). Nevertheless, there is still uncertainty regarding clinical breakpoints with 3 different values depending on countries (8 mg/L, 16 mg/L, 32 mg/L), moreover international consensus about this issue is awaited. In this context, three original studies were conducted along with a literature review. First, in vitro susceptibility to temocillin of 762 enterobacterales from community-acquired urinary tract infection was studied. In this area of low prevalence of ESBL and no CPE, the three routine susceptibility methods (disk diffusion, automate, Etest) were very accurate, epidemiological cut-off was set to 8 mg/L. Then, temocillin efficacy against enterobacterales producing or not producing ß-lactamase (ESBL or CPE) was assessed by two complementary murine models. We demonstrated that temocillin exposure reproducing 2 g q12h regimen showed efficacy against strains with temocillin MIC of 8 mg/L. This regimen exhibited a lower, even though significant, efficacy against strain with temocillin MIC of 16 mg/L. On the over hand, it was not observed significant efficacy against strain with temocillin MIC of 32 mg/L whatever the regimen used (2 g q12h or q8h). All together this results and the literature review support a clinical breakpoints of 8 mg/L for2 g q12h regimen, and 16 mg/L for 2 g q8h regimen. This last proposition correspond to the new susceptibility category : “Intermediate – Susceptible, increase exposure” from the last EUCAST recommendations.
73

The Impact of Phagocyte-UPEC Interactions Upon Pathogenesis of Urinary Tract Infections

Horvath, Dennis John, Jr. 20 October 2011 (has links)
No description available.
74

Estrategias de prevención en el manejo del cateterismo vesical utilizadas por enfermeras de un hospital II-2 Chiclayo, 2023

Quiroz Braco, Luciana Graciela Edith Dareana January 2024 (has links)
Las infecciones urinarias asociadas al catéter vesical son un problema de salud pública que con mayor frecuencia se presentan en los servicios de emergencia, amenaza la seguridad del paciente, origina daños en el estado de salud y aumenta las probabilidades morbilidad y mortalidad. Ante ello, los profesionales de enfermería deben capacitarse en el manejo adecuado del cateterismo vesical a través de las estrategias de prevención; logrando desarrollar la inserción, mantenimiento y retiro apropiado del catéter vesical, cumpliendo con la técnica aséptica. Por esta razón, la investigación consideró como objetivo: Describir y analizar las estrategias de prevención en el manejo del cateterismo vesical utilizadas por enfermeras de un hospital II-2 Chiclayo, 2023. El tipo de investigación empleó un abordaje descriptivo y la población estuvo conformada por enfermeras que trabajan o trabajaron en el servicio de emergencia del Hospital Las Mercedes Chiclayo. La muestra fue de 12 enfermeras, se estableció por saturación y redundancia, se abordó el muestreo no probabilístico por conveniencia. Los resultados demostraron que las estrategias preventivas se aplican antes, durante y después de la inserción del catéter vesical, evidenciándose en las siguientes categorías: Intervenciones de enfermería como estrategias efectivas previas al cateterismo vesical, Intervenciones de enfermería estratégicas para el mantenimiento y retiro del catéter vesical, Care bundle como estrategia para la seguridad del paciente. En conclusión, las estrategias de prevención de infecciones urinarias más relevantes fueron la higiene de manos, la higiene de la zona genital, la esterilidad del procedimiento y rotular la fecha de colocación y de cambio del catéter vesical. / Urinary infections associated with bladder catheters are a public health problem that most frequently occur in emergency services, threatening patient safety, causing damage to health status and increasing the likelihood of morbidity and mortality. Given this, nursing professionals must be trained in the proper management of bladder catheterization through prevention strategies; managing to develop the appropriate insertion, maintenance and removal of the bladder catheter, complying with aseptic technique. For this reason, the research considered the objective: To describe and analyze the prevention strategies in the management of bladder catheterization used by nurses at a hospital II-2 Chiclayo, 2023. The type of research used a descriptive approach and the population was made up of nurses who work or worked in the emergency service of the Hospital Las Mercedes Chiclayo. The sample consisted of 12 nurses, it was established by saturation and redundancy, non-probabilistic sampling was used for convenience. The results demonstrated that preventive strategies are applied before, during and after the insertion of the bladder catheter, evident in the following categories: Nursing interventions as effective strategies prior to bladder catheterization, Strategic nursing interventions for the maintenance and removal of the bladder catheter , Care bundle as a strategy for patient safety. In conclusion, the most relevant urinary infection prevention strategies were hand hygiene, hygiene of the genital area, sterility of the procedure and labeling the date of placement and change of the bladder catheter.
75

Utvärdering av direktresistensmetod på urinodlingar gentemot EUCAST diskdiffusionsmetod

Andersson, Jelena January 2019 (has links)
Urinvägsinfektioner är den näst vanligaste anledningen till antibiotikaförskrivning i Sverige. För diagnos av UVI i urinkultur med standardmetoden krävs 18 - 48 timmar och ytterligare 24 timmar i odling tills resultaten för antimikrobiell känslighetstestning är tillgängliga. Direktresistensmetoden ger svar 24 timmar tidigare än standardmetoden. Studiens syfte var att utvärdera direktresistensmetoden (in-housemetod) från mikrobiologiska laboratoriet Unilabs, Skövde på urinodlingar från patientprover och jämföra den med EUCAST-diskdiffusionsmetod. I denna studie användes 334 bakteriestammar från urinodlingar; E. coli (n=211) E. faecalis (n=45), Klebsiella spp (n=37), P. mirabilis (n= 17) och övriga gramnegativa bakteriestammar (n=24). Direktresistensmetoden och EUCAST diskdiffusionsmetod har utförts parallellt på alla bakteriestammar och sex olika antibiotikatyper testades. Hämningszonernas diameter lästes av och placerades i rätt S, I, R kategori för respektive antibiotikum. Från sammanlagt 1674 testade antibiotikalappar hittades 23 avvikelser där E. coli representerade 13 av dessa. Mecillinam var det antibiotikum där flest avvikelser noterades, totalt tio stycken. Överensstämmelsen mellan de två metoderna var 98,6% från 1674 testade antibiotikalappar. Direktresistensmetoden leder till att patienten få ett svar 24 timmar tidigare än med EUCAST diskdiffusionsmetoden där svaret inkluderar även resistensbestämning. / Urinary tract infections are the second most common reason for prescription of antibiotics in Sweden. Diagnosis of UTIs in urine culture by the standard method requires 18 to 48 hours and an additional 24 hours until antimicrobial testing is available. The direct resistance method provides answers 24 hours earlier than the standard method. The aim of the study was to evaluate the direct resistance method (in-house method) from the microbiological laboratory Unilabs, Skövde on urine cultures from patient samples and compare it with the EUCAST disc diffusion method. For this study, 334 bacterial strains from urinary cultures were used; E. coli (n = 211) E. faecalis (n = 45), Klebsiella spp (n = 37), P. mirabilis (n = 17) and other gram-negative rods (n = 24). The direct resistance method and the EUCAST disk diffusion method were performed in parallel on all bacterial strains and six different types of antibiotics were tested. The diameter of the inhibition zones was measured and categorized according to S, I, R for each antibiotic. From a total of 1674 tested antibiotics 23 discrepancies were found where E. coli represented 13 of these. Mecillinam was the antibiotic where most discrepancies were noted, a total of ten. The agreement between the two methods was 98,6% from 1674 tested antibiotics. The direct resistance method allows a response to the patient 24 hours earlier than the EUCAST disc diffusion method.
76

Growth Dynamics, Antibiotic Susceptibility and the Effect of Sublethal Ciprofloxacin Concentrations in Susceptible and Resistant Escherichia coli in Biofilm / Tillväxtdynamik, Antibiotikakänslighet och Effekten av Subletala Koncentrationer av Ciprofloxacin på Känsliga och Resistenta Escherichia coli i Biofilm

Fernberg, Jenny January 2019 (has links)
Instead of planktonic growth in nature, many species of bacteria form biofilm to survive in harsh conditions. Although many chronic bacterial infections are caused by bacterial species in a biofilm lifestyle, previous research has focused on studying antibiotic resistance in planktonic growth. Here we used a modified MBEC assay, i.e. biofilm growth on pegs, to determine Escherichia coli biofilm inhibitory concentrations (BIC) of ciprofloxacin, streptomycin and rifampicin and to study the minimal selective concentration (MSC) for ciprofloxacin in E. coli biofilm. We could observe high inhibitory concentrations for all antibiotics in the biofilm pre-formed in media without antibiotics compared to the biofilm formed in antibiotics. We also show preliminary result indicating that sublethal concentrations of ciprofloxacin lead to the selection of ciprofloxacin resistant mutants in biofilm and that the selection level is lower than what was observed in planktonic growing E. coli. With more knowledge in how the biofilm formation precedes in different antibiotic settings, the treatment for chronic biofilm infections used today could be evaluated and changed so that the infections could be eradicated.
77

Rules of Thumb and Management of Common Infections in General Practice

André, Malin January 2004 (has links)
<p>This thesis deals with problem solving of general practitioners (GPs), which is explored with different methods and from different perspectives. The general aim was to explore and describe rules of thumb and to analyse the management of respiratory and urinary tract infections (RTI and UTI) in general practice in Sweden. The results are based upon focus group interviews concerning rules of thumb and a prospective diagnosis-prescription study concerning the management of patients allocated a diagnosis of RTI or UTI. In addition unpublished data are given from structured telephone interviews concerning specific rules of thumb in acute sinusitis and prevailing cough.</p><p>GPs were able to verbalize their rules of thumb, which could be called tacit knowledge. A specific set of rules of thumb was used for rapid assessment when emergency and psychosocial problems were identified. Somatic problems seemed to be the expected, normal state. In the further consultation the rules of thumb seemed to be used in an act of balance between the individual and the general perspective. There was considerable variation between the rules of thumb of different GPs for patients with acute sinusitis and prevailing cough. In their rules of thumb the GPs seemed to integrate their medical knowledge and practical experience of the consultation. A high number of near-patient antigen tests to probe Streptococcus pyogenes (Strep A tests) and C-reactive protein (CRP) tests were performed in patients, where testing was not recommended. There was only a slight decrease in antibiotic prescribing in patients allocated a diagnosis of RTI examined with CRP in comparison with patients not tested. In general, the GPs in Sweden adhered to current guidelines for antibiotic prescribing. Phenoxymethylpenicillin (PcV) was the preferred antibiotic for most patients allocated a diagnosis of respiratory tract infection.</p><p>In conclusion, the use of rules of thumb might explain why current practices prevail in spite of educational efforts. One way to change practice could be to identify and evaluate rules of thumb used by GPs and disseminate well adapted rules. The use of diagnostic tests in patients with infectious illnesses in general practice needs critical appraisal before introduction as well as continuing surveillance. The use of rules of thumb by GPs might be one explanation for variation in practice and irrational prescribing of antibiotics in patients with infectious conditions.</p> / On the day of the public defence the status of the articles IV and V was: Accepted.
78

Rules of Thumb and Management of Common Infections in General Practice

André, Malin January 2004 (has links)
This thesis deals with problem solving of general practitioners (GPs), which is explored with different methods and from different perspectives. The general aim was to explore and describe rules of thumb and to analyse the management of respiratory and urinary tract infections (RTI and UTI) in general practice in Sweden. The results are based upon focus group interviews concerning rules of thumb and a prospective diagnosis-prescription study concerning the management of patients allocated a diagnosis of RTI or UTI. In addition unpublished data are given from structured telephone interviews concerning specific rules of thumb in acute sinusitis and prevailing cough. GPs were able to verbalize their rules of thumb, which could be called tacit knowledge. A specific set of rules of thumb was used for rapid assessment when emergency and psychosocial problems were identified. Somatic problems seemed to be the expected, normal state. In the further consultation the rules of thumb seemed to be used in an act of balance between the individual and the general perspective. There was considerable variation between the rules of thumb of different GPs for patients with acute sinusitis and prevailing cough. In their rules of thumb the GPs seemed to integrate their medical knowledge and practical experience of the consultation. A high number of near-patient antigen tests to probe Streptococcus pyogenes (Strep A tests) and C-reactive protein (CRP) tests were performed in patients, where testing was not recommended. There was only a slight decrease in antibiotic prescribing in patients allocated a diagnosis of RTI examined with CRP in comparison with patients not tested. In general, the GPs in Sweden adhered to current guidelines for antibiotic prescribing. Phenoxymethylpenicillin (PcV) was the preferred antibiotic for most patients allocated a diagnosis of respiratory tract infection. In conclusion, the use of rules of thumb might explain why current practices prevail in spite of educational efforts. One way to change practice could be to identify and evaluate rules of thumb used by GPs and disseminate well adapted rules. The use of diagnostic tests in patients with infectious illnesses in general practice needs critical appraisal before introduction as well as continuing surveillance. The use of rules of thumb by GPs might be one explanation for variation in practice and irrational prescribing of antibiotics in patients with infectious conditions. / On the day of the public defence the status of the articles IV and V was: Accepted.
79

NMR as a tool in drug research : Structure elucidation of peptidomimetics and pilicide-chaperone complexes

Hedenström, Mattias January 2004 (has links)
In the last decades NMR spectroscopy has become an invaluable tool both in academic research and in the pharmaceutical industry. This thesis describes applications of NMR spectroscopy in biomedicinal research for structure elucidation of biologically active peptides and peptidomimetics as well as in studies of ligand-protein interactions. The first part of this thesis describes the theory and methodology of structure calculations of peptides using experimental restraints derived from NMR spectroscopy. This methodology has been applied to novel mimetics of the peptide hormones desmopressin and Leu-enkephalin. The results of these studies highlight the complicating issue of conformational exchange often encountered in structural determination of peptides and how careful analysis of experimental data as well as optimization of experimental conditions can enable structure determinations in such instances. Although the mimetics of both desmopressin and Leu-enkephalin were found to adopt the wanted conformations, they exhibited no or very poor biological activity. These results demonstrate the difficulties in designing peptidomimetics without detailed structural information of the receptors. A stereoselective synthetic route towards XxxΨ[CH2O]Ala pseudodipeptides is also presented. Such pseudodipeptides can be used as isosteric amide bond replacements in peptides in order to increase their resistance towards proteolytic degradation. The second part of this thesis describes the study of the interaction between compounds that inhibit pilius assembly, pilicides, and periplasmic chaperones from uropathogenic Escherichia coli. Periplasmic chaperones are key components in assembly of pili, i.e. hair-like protein complexes located on the surface of Escherichia coli that cause urinary tract infections. Detailed knowledge about this interaction is important in understanding how pilicides can inhibit pilus assembly by binding to chaperones. Relaxation-edited NMR experiments were used to confirm the affinity of the pilicides for the chaperones and chemical shift mapping was used to study the pilicide-chaperone interaction surface. These studies show that at least two interaction sites are present on the chaperone surface and consequently that two different mechanisms resulting in inhibition of pilus assembly may exist.
80

Lipopolysaccharide (LPS) core biosynthesis in "Proteus mirabilis" / Estudio de la biosíntesis del núcleo de lipopolisacarido (LPS) en "Proteus mirabilis"

Aquilini, Eleonora 11 January 2013 (has links)
Urinary tract infection (UTIs) is an extremely common disease. Proteus mirabilis is a common cause of UTI in individuals with functional or structural abnormalities or with long-term catheterization, it forms bladder and kidney stones as a consequence of urease-mediated urea hydrolysis. Known virulence factors, besides urease, are flagella, fimbriae, outer membrane proteins, hemolysins, amino acid deaminase, protease, capsule and lipopolysaccharide (LPS). Study of LPS core is particularly relevant for several reasons: it is a conserved region, although it is increasingly clear that there is some variability at the genus or groups of similar genera, its chemical structure modulates the endotoxic activity of lipid A, alteration of the LPS core, which generates less virulent bacteria, encourages the search of substances that interfere with the biosynthesis of this region, and conserved regions of the core LPS could be useful as antigens in preventing diseases caused by pathogens that contain these conserved regions. The specific aims of this project have been to identify and functionally characterize genes involved in core LPS biosynthesis in P. mirabilis, to elucidate the mechanism of incorporation of galactosamine (GalN) to the core LPS, to identify genes coding for phosphoethanolamine (PEtN) modifications, and to characterize and to study the biological effects of the gene encoding the PEtN transferase involved in the modification of the second heptose residue (L,D-HepII). We found that P. mirabilis has most of the genes for the biosynthesis of LPS core grouped in the waa cluster in the chromosome. Despite this, additional genes required for core LPS biosynthesis are found outside the waa cluster. The pentasaccharide of the inner core, shared by all Enterobacteriaceae, is biosynthesized in P. mirabilis, by the sequential activity of a bifunctional transferase (WaaA) and three heptosyltransferases (WaaC, WaaF, and WaaQ). These enzymes are transcribed from genes located inside the waa cluster, and are conserved in P. mirabilis strains analyzed; for more, they show a high identity and similarity level to homologues proteins of Escherichia coli, Klebsiella penumoniae and Serratia marcescens. The waaL gene, coding for the O-antigen polymerase ligase, is found adjacent to the classic waa cluster. Downstream this gene, four genes encoding enzymes belonging to the 4 (walM, walN, and WalR), and 9 (walO) glycosyltransferase family were found. Even if members of these families were related to LPS core biosynthesis in several Gram-negative bacteria, in P. mirabilis they do not appear to be involved in the biosynthesis of the reported core LPS structures. The presence of the disaccharide hexosamine (HexN)-1,4-galacturonic acid (GalA) is a feature of P. mirabilis LPS outer core. Depending on the nature of the HexN outer core residue, two different homologues for N-acetyl-hexosamine transferases are present in the waa cluster: wabH or wabP. Altought the incorporation of glucosamine into LPS core requires an acetylglucosaminyltransferase (WabH) and a deacetilase (WabN), the incorporation of GalN requires three enzymes: an acetylgalactosaminyltransferase (WabP), a deacetilase (WabN) and an epimerase (gne). An amplification test with specific primers for this two different homologues can be used to predict the HexN nature in P. mirabilis LPS cores. The strain-specific genes wamB and wamC code for a galactosyltransferase and a heptosyltransferase respectively in strain R110 of P. mirabilis. The enzyme encoded by gene wamD is a N-acetylglucosaminyltransferase, and it is found in strain 51/57 of P. mirabilis. WamA, coded by wamA gene in the waa cluster of strains R110, 50/57, TG83 and HI4320, is a heptosyltransferase responsible for the incorporation of a quarter residue of heptose (Hep), in DD configuration, to the GalA II of the outer core. In P. mirabilis strain 51/57, a gene coding a protein of the Mig-14 family was identified inside the waa cluster, this localization appears to be an exception in the Enterobacteriaceae family. Inspection of the whole genome of P. mirabilis HI4320 did not allow the identification of a mig-14 similar gene. There are three putative PEtN transferases in the genome of P. mirabilis: PMI3040, PMI3576, and PMI3104. The gene identified as eptC (PMI3104) transfers the moiety of PEtN to the O-6 position of L,D-Hep II (HepII6PEtN). The absence of the positive charge due to PEtN residue doesn't affect the bacterial growth kinetics in lab conditions in rich or defined media, but causes a moderate destabilization of the outer-membrane. Despite the lack of the PEtN residue on the Hep II in P. mirabilis LPS core, has no statistically effects during urinary tract infection assays in mouse model, the absence of this modification causes an increase sensitivity to complement in non-immune human sera. / P. mirabilis no es una causa frecuente de infecciones urinarias en el huésped normal, más bien infecta el tracto urinario con alteraciones funcionales o anatómicas, o instrumentación crónica como el cateterismo. P. mirabilis está a menudo asociado con cálculos urinarios e incrustaciones de los catéteres y es, particularmente importante, en pacientes con cateterización prolongada. Las infecciones del tracto urinario asociadas a cateterización son mundialmente reconocidas como la causa más común de infección asociada a tratamientos en ambiente hospitalario. El LPS es un factor de virulencia importante en bacterias Gram negativas patógenas. También conocido como endotoxina, es una molécula glicolipídica que constituye la estructura mayoritaria de la cara externa de la membrana externa (OM). En Proteus mirabilis la mayoría de los genes responsables de la biosíntesis de núcleo de LPS están localizados en el cromosoma, en el agrupamiento génico waa. A pesar de esto, algunos genes adicionales, necesarios para la biosíntesis del núcleo de LPS, se encuentran ubicados fuera del agrupamiento génico waa. El pentasacárido del núcleo interno, común a todas las Enterobacteriáceae, se biosintetiza en P. mirabilis, por la actividad secuencial de una transferasa bifunciona (WaaA) y tres heptosiltransferasas (WaaC, WaaF, y WaaQ). La presencia del disacárido HexN‐1,4‐GalA es característica del núcleo externo de LPS en P. mirabilis. Dependiendo de la naturaleza del residuo de HexN, se encuentran, en el agrupamiento génico waa, dos HexNAc transferasas diferentes: wabH o wabP. El gen eptC (PMI3104) codifica para la enzima que transfiere el residuo de fosfoetanolamina a la posición O-6 de la L,D-Hep II (HepII6PEtN), en el núcleo de LPS de P. mirabilis. La ausencia de la carga positiva del residuo de fosfoetanolamina no afecta a la cinética de crecimiento de las bacterias en condiciones standard de laboratorio sea en medios ricos o definidos. La ausencia del residuo fosfoetanolamina provoca una desestabilización moderada de la membrana externa que se traduce en una disminución de la MIC para SDS.

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