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Resumen Introducción.Pseudomona sp como rizobacteria promotora del crecimiento vegetal es muy utilizada en diversos cultivos, ya que promueve el crecimiento y previene la colonización de patógenos. Objetivo. Evaluar la influencia de Pseudomona spen la emergencia de las semillas y el desarrollo de posturas de Theobroma cacao L. en suelos fersialíticos pardos rojizo de Jibacoa. Materiales y métodos. La investigación se realizó en el 2018 en la Estación Experimental Agro-Forestal de Jibacoa en el municipio Manicaragua, provincia Villa Clara, Cuba. En un diseño de bloques al azar con 3 réplicas, se estudiaron 3 tratamientos: a - Control: siembra de semillas en un sustrato compuesto por 3 partes de suelo y una de abono orgánico (3/1); b - siembra de semillas en un sustrato 5/1; c - sustrato 5/1 con siembra de semillas peletizadas con Pseudomona sp. Se evaluó la emergencia de las semillas y a 10 posturas se le midieron la altura, el diámetro del tallo, la masa seca y el área foliar. Resultados. La aplicación de Psedomonaspa las semillas del cacao en el momento de la siembra incrementó su emergencia en un 14,57% con respecto a las no peletizadas en igual volumen de abono orgánico y en un 4,18% con respecto al tratamiento control. Este biofertilizante aumentó la masa seca y el área foliar en un 18,3% y 37,8% respectivamente en el sustrato 5/1, y en 18,3% y 46,9% de igual manera con respecto al tratamiento control. Conclusiones. La aplicación de Psedomonasp a las semillas del cacao en el momento de la siembra provoca efectos positivos en la emergencia y el desarrollo de las posturas de cacao al aumentar su peso seco y área foliar. Abstract Introduction.Pseudomonasp as a plant growth promoting rhizobacteria is widely used in various crops that promotes growth and prevent pathogen colonization. Objective. To evaluate the influence of Pseudomonasp on the emergence of seeds and the development of Theobroma cacao L. seedlings in reddish brown fersialitic soils of Jibacoa. Materials and methods. The research was carried out in 2018 at the JibacoaAgro-Forestry Experimental Station in the Manicaragua municipality, Villa Clara province, Cuba. In a randomized block design with 3 replications, 3 treatments were studied: a- Control: sowing seeds in a substrate composed of 3 parts of soil and one part of organic fertilizer (3/1); b- sowing seeds in a substrate 5/1; c- substrate 5/1 with sowing of pelleted seeds with Pseudomonasp. The emergence of the seeds was evaluated and the height, stem diameter, dry mass and leaf area were measured at 10 positions. Results. The application of Psedomonaspto cocoa beans at the time of sowing increased their emergence by 14.57% with respect to those not pelleted in the same volume of organic fertilizer and by 4.18% with respect to the control treatment. This biofertilizer increased the dry mass and leaf area by 18.3% and 37.8% respectively in the 5/1 substrate, and by 18.3% and 46.9% in the same way with respect to the control treatment. Conclusions. The application of Psedomonasp to the seeds at the time of sowing causes positive effects in the emergence and development of the seedlings by increasing their dry weight and leaf area.

Objectives: To compare the clinical and microbiological outcomes of patients treated with beta-lactam monotherapy or combination therapy for Pseudomonas aeruginosa infections. Data sources: MEDLINE, Google Scholar and the Cochrane Library.Study eligibility criteria and interventions: Experimental and observational studies published as full papers up to December 2020 that compared the efficacy of beta-lactams used as monotherapy or in combination with other active agents as empirical or targeted therapy for bloodstream infections or hospital-acquired pneumonia/ventilator-associated pneumonia due to P. aeruginosa were included in this meta-analysis. The outcomes evaluated were in-hospital mortality rate, 14 -day-or 30-day-mortality rate, microbiological cure rate and clinical cure rate.Results: Of 8363 citations screened, six randomized controlled trials, six prospective cohort studies and 21 retrospective cohort studies were included in the analysis, accounting for a total of 3861 subjects. Considering the 14 studies evaluating empirical therapy, no significant difference in mortality rate was observed between the two groups [relative risk (RR) 1.06, 95% confidence interval (CI) 0.86-1.30; P = 0.6]. Similar findings were obtained among the 18 studies analysing targeted therapy (RR 1.04, 95% CI 0.83- 1.31; P = 0.708); however, grouping the studies by design, higher mortality was observed among patients receiving monotherapy in five prospective studies (RR 1.37, 95% CI 1.06-1.79; P = 0.018). Finally, no differ-ence was observed between groups in terms of microbiological cure and clinical cure.Conclusions: This meta-analysis demonstrated no difference in mortality rate, clinical cure rate and mi-crobiological cure rate in patients treated with beta-lactam monotherapy or combination therapy for P. aeruginosa infections.(c) 2021 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.

Infections caused by metallo-β-lactamase (MBL)-producing Enterobacterales and Pseudomonas are increasingly reported worldwide and are usually associated with high mortality rates (>30%). Neither standard therapy nor consensus for the management of these infections exist. Aztreonam, an old β-lactam antibiotic, is not hydrolyzed by MBLs. However, since many MBL-producing strains co-produce enzymes that could hydrolyze aztreonam (e.g., AmpC, ESBL), a robust β-lactamase inhibitor such as avibactam could be given as a partner drug. We performed a systematic review including 35 in vitro and 18 in vivo studies on the combination aztreonam + avibactam for infections sustained by MBL-producing Gram-negatives. In vitro data on 2209 Gram-negatives were available, showing the high antimicrobial activity of aztreonam (MIC ≤ 4 mg/L when combined with avibactam) in 80% of MBL-producing Enterobacterales, 85% of Stenotrophomonas and 6% of MBL-producing Pseudomonas. Clinical data were available for 94 patients: 83% of them had bloodstream infections. Clinical resolution within 30 days was reported in 80% of infected patients. Analyzing only patients with bloodstream infections (64 patients), death occurred in 19% of patients treated with aztreonam + ceftazidime/avibactam. The combination aztreonam + avibactam appears to be a promising option against MBL-producing bacteria (especially Enterobacterales, much less for Pseudomonas) while waiting for new antimicrobials.

BACKGROUND We report the case of an 11-year-old girl with a recent diagnosis of common B-cell acute lymphoblastic leukemia who presented with Pseudomonas aeruginosa pyomyositis of the left lower limb during severe neutropenia associated with the induction phase of chemotherapy. OBSERVATIONS Presenting signs included fever, leg pain, and refusal to walk. Popliteal knee ultrasonography was unremarkable, whereas magnetic resonance imaging showed 2 intramuscular fluid collections requiring surgically drainage. CONCLUSION A review of medical literature showed that pyomyositis is an infrequent complication in children with hematological malignancies, and most cases are due to Staphylococcus aureus, whereas Pseudomonas aeruginosa appears to be rarely involved.

Antarctic bacteria are able to survive under extreme environmental conditions and have adapted to exploit some of the most ephemeral nutrient pockets. Importantly, such strains have been often shown to be capable of synthesizing compounds of valuable biotechnological importance. Here we show that Pseudomonas sp. TAE6080, a possibly new bacterium isolated in 1994 during water column samplings near the French Antarctic station Dumont d'Urville, is capable of inhibiting the formation of Staphylococcus epidermidis biofilm, known to be an important opportunistic pathogen in infections associated to medical devices. A better understanding of this bacterium can therefore provide useful insight on new bioactive molecules that could play a role against chronic infections. To this end, the anti-biofilm effect of cell-free supernatant of Pseudomonas sp. TAE6080 was evaluated on S. epidermidis RP62A biofilm formation, demonstrating that it significantly reduced its aggregation. Furthermore, genome sequencing, assembly and mining revealed a plethora of putative biosynthetic gene clusters that might be involved in biofilm disruption. The experimental and genomic data presented here open the venue to further investigations on the molecular basis underlying biofilm inhibition.

One of the biggest environmental problems is related to mining effluents with cyanide, due to its high degree of toxicity, it causes highly significant impacts on the ecosystem in general. Although there are various technologies for its treatment, bioremediation is a potential alternative because it is friendly to the environment. The main objective is to analyze the main microorganisms used to carry out bioremediation processes of mining effluents with cyanide. A review of the different sources of information on cyanide bioremediation microorganisms was carried out. Finding that a wide diversity of microorganisms that can be used as potential biological agents to bioremedy cyanide are reported, among which those of the genus of Pseudomonas and Bacillus stand out; the main factors that must be taken into account to achieve high efficiencies are pH, temperature, nutrients, biomass concentration and cyanide concentration. Bioremediation using microorganisms is increasingly taking a position to remedy contaminants such as cyanide, but even so in Peru there is a lack of further studies at the pilot and plant level to demonstrate its efficiency, which is achieved at the laboratory level. Uno de los mayores problemas ambientales que se tiene es referente a los efluentes mineros con cianuro, por su alto grado de toxicidad ocasiona impactos altamente significativos en el ecosistema en general. A pesar de que existen diversas tecnologías para su tratamiento, la biorremediación es una alternativa potencial por ser amigable con el medio ambiente. Se tiene como objetivo principal analizar los principales microorganismos empleados para llevar acabo procesos de biorremediación de efluentes mineros con cianuro. Se realizó una revisión de las distintas fuentes de información de microorganismos biorremediadores de cianuro. Hallándose que se reportan una amplia diversidad de microorganismos que se pueden emplear como agentes biológicos potenciales para biorremediar el cianuro, entre las que sobresalen las del género de Pseudomonas y Bacillus; los principales factores que se debe tener en cuenta para lograr altas eficiencias son el pH, temperatura, nutrientes, concentración de la biomasa y concentración de cianuro. La biorremediación empleando microorganismos cada vez va tomando mayor posición para remediar contaminantes como el cianuro pero aun así en el Perú faltan mayores estudios a nivel piloto y planta para demostrar su eficiencia que se logra a nivel laboratorio.

Pentachlorophenol (PCP) is a toxic compound, which is widely used as a wood preservative product and general biocide. It is persistent in the environment and has been classified as a persistent organic pollutant to be reclaimed in many countries. Bioremediation is an emerging approach to rehabilitating areas polluted by recalcitrant xenobiotics. In the present study, we evaluated the potential of three strains of Pseudomonas (P. putida S121, P. rhizophila S211, and P. fuscovagiceae S115) as bioremediation agents in depletion and detoxification of PCP in soil microcosms. PCP removal was effectively optimized using a central-composite experimental design and response surface methodology (RSM). The optimum conditions for maximum PCP removal yield (85 ± 5%) were: 500mg/kg PCP concentration, 108 UFC/g soil inoculum size of each strain and 55days incubation period. The bacterial strains, P. putida, P. rhizophila, and P. fuscovagiceae, showed good capability to tolerate and degrade PCP so that they could be successfully used in synergistic effect to treat PCP polluted soils.

In semiarid regions is important to use native strains best adapted to these environments to optimize plant-PGPR interaction. We aimed to isolate and characterize PGPR from roots and rhizosphere of a tomato crop, as well as studying the effect of its inoculation on tomato seedlings growth. We selected four strains considering their effectiveness of fixing nitrogen, solubilizing phosphate, producing siderophores and indole acetic acid. They belong to the genera Enterobacter, Pseudomonas, Cellulosimicrobium, and Ochrobactrum. In addition, we also analyzed the ability to solubilize Ca3(PO4)2, FePO4 and AlPO4 and the presence of one of the genes encoding the cofactor PQQ in their genome. Enterobacter 64S1 and Pseudomonas 42P4 showed the highest phosphorus solubilizing activity and presence of pqqE gene. Furthermore, in a tomato-based bioassay in speed-bed demonstrated that a sole inoculation at seedling stage with the strains increased dry weight of roots (49–88%) and shoots (39–55%), stem height (8–13%) and diameter (5–8%) and leaf area (22–31%) and were equal or even higher than fertilization treatment. Leaf nitrogen and chlorophyll levels were also increased (50–80% and 26–33%) compared to control. These results suggest that Enterobacter 64S1 and Pseudomonas 42P4 can be used as bio-inoculant in order to realize a nutrient integrated management. Fil: Pérez Rodriguez, María Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Piccoli, Patricia Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Anzuay, María Soledad. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Baraldi, Rita. Consiglio Nazionale delle Ricerche; Italia Fil: Neri, Luisa. Consiglio Nazionale delle Ricerche; Italia Fil: Taurian, Tania. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto; Argentina Fil: Lobato Ureche, Miguel Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Segura, Diana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina Fil: Cohen, Ana Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina

In this study, the Pseudomonas corrugata strain CFBP 5454 and the P. mediterranea strain CFBP 5447 were shown to produce diffusible compounds that inhibit the in vitro growth of plant pathogenic fungi and bacteria and antifungal volatile compounds. In addition, both bacterial strains were found to produce cyanide. Mutant derivatives in LuxR transcriptional regulators, i.e. P. corrugata GL2 (pcoR mutant) and GLRFIA (rfiA mutant), and P. mediterranea PSMER (pmeR mutant) and PSRFIA (rfiA mutant) impaired in cyclic lipopeptide (CLP) production, showed a diffusible compound-mediated reduced activity, depending on the biocontrol strain, challenge microorganism and culture medium. The volatile compound-mediated activity and cyanide production were not affected in the mutants. Genome analysis of the P. corrugata strain CFBP 5454 led to the identification of putative genes involved in the hydrogen cyanide (HCN) biosynthesis. HCN is a volatile organic compound (VOC), and as in other Pseudomonas, the HCN cluster consisted of three contiguous structural genes, hcnABC, which together encoded a membrane-bound HCN synthase complex, which was sufficient for cyanogenesis. The putative hcnA gene was insertionally inactivated. A genomic mutant was characterized, and the role of this compound in biocontrol activity was investigated. A qualitative test for the detection of HCN production confirmed that in the hcnA mutant strain, metabolite production is completely abolished. In vitro experiments on the phytopathogenic fungus Botrytis cinerea also showed that HCN production is mainly involved in conidia germination inhibition.

Objectives The aim of this study was to assess colistin use in a country endemic for multidrug-resistant Gram-negative bacteria (MDR-GNB). Methods Colistin prescription patterns were evaluated in 22 Italian centres. Factors associated with use of colistin in combination with other anti-MDR-GNB agents were also assessed. Results A total of 221 adults receiving colistin were included in the study. Their median age was 64 years (interquartile range 52–73 years) and 134 (61%) were male. Colistin was mostly administered intravenously (203/221; 92%) and mainly for targeted therapy (168/221; 76%). The most frequent indications for colistin therapy were bloodstream infection and lower respiratory tract infection. Intravenous colistin was administered in combination with at least another anti-MDR-GNB agent in 80% of cases (163/203). A loading dose of 9 MU of colistimethate was administered in 79% of patients receiving i.v. colistin and adequate maintenance doses in 85%. In multivariable analysis, empirical therapy [odds ratio (OR) = 3.25, 95% confidence interval (CI) 1.24–8.53;P = 0.017] and targeted therapy for carbapenem-resistant Enterobacterales infection (OR = 4.76, 95% CI 1.69–13.43; P = 0.003) were associated with use of colistin in combination with other agents, whilst chronic renal failure (OR = 0.39, 95% CI 0.17–0.88; P = 0.024) was associated with use of colistin monotherapy. Conclusion Colistin remains an important option for severe MDR-GNB infections when other treatments are not available. Despite inherent difficulties in optimising its use owing to peculiar pharmacokinetic/pharmacodynamic characteristics, colistin was mostly used appropriately in a country endemic for MDR-GNB.

The ability of plants to take up phosphorus (P) from soil depends on root morphology and root exudates release and can be modulated by beneficial soil microbes. These microbes can solubilize P, affect root elongation and branching, and lead to a higher uptake of P and other nutrients. However, coordination of these mechanisms is unclear, especially the mechanism for changing the available form of P. We aimed to dissect the effects of two different beneficial microbial taxa (plant growth-promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF)) on root morphological traits, plant nutrient content, and growth in tomato and corn fertilized with either Gafsa rock phosphate (RP) or triple superphosphate (TSP), which have contrasting solubility levels. Tomato and corn were grown in pots and inoculated with one of three PGPB species or a mix of two AMF species or were not inoculated. Root traits, botanical fractions, and the contents of various mineral nutrients were measured. TSP stimulated tomato biomass accumulation compared to RP but did not stimulate corn biomass accumulation. PGPB improved the growth of both plant species under RP, with limited differences among the strains, whereas AMF only improved tomato growth under TSP. These differences between microbial systems were explained by a bacterial effect on the total root length but not on the mean root diameter and by the ability of AMF to improve the mineral nutrient content. The effects of PGPB were less dependent on the plant species and on P form than the effects of AMF.These results have implications for the improvement of the early plant growth through the management of beneficial microbes.

Pseudomonas donghuensis strain SVBP6, an isolate from an agricultural plot in Argentina, displays a broad-spectrum and diffusible antifungal activity, which requires a functional gacS gene but could not be ascribed yet to known secondary metabolites typical of Pseudomonas biocontrol species. Here, we report that Tn5 mutagenesis allowed the identification of a gene cluster involved in both the fungal antagonism and the production of a soluble tropolonoid compound. The ethyl acetate extract from culture supernatant showed a dose-dependent inhibitory effect against the phytopathogenic fungus Macrophomina phaseolina. The main compound present in the organic extract was identified by spectroscopic and X-ray analyses as 7-hydroxytropolone (7HT). Its structure and tautomerism was confirmed by preparing the two key derivatives 2,3-dimethoxy- and 2,7-dimethoxy-tropone. 7HT, but not 2,3- or 2,7-dimethoxy-tropone, mimicked the fungal inhibitory activity of the ethyl acetate extract from culture supernatant. The activity of 7HT, as well as its production, was barely affected by the presence of up to 50 μM added iron (Fe+2). To summarize, P. donghuensis SVBP6 produces 7HT under the positive control of the Gac-Rsm cascade and is the main active metabolite responsible for the broad-spectrum inhibition of different phytopathogenic fungi. Fil: Muzio, Federico Matías. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnologia. Centro de Bioquimica y Microbiologia de Suelos. Laboratorio de Fisiologia, Genetica de Bacterias Para Plantas.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Agaras, Betina Cecilia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnologia. Centro de Bioquimica y Microbiologia de Suelos. Laboratorio de Fisiologia, Genetica de Bacterias Para Plantas.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Masi, Marco. Università degli Studi di Napoli Federico II; Italia Fil: Tuzi, Angela. Università degli Studi di Napoli Federico II; Italia Fil: Evidente, Antonio. Università degli Studi di Napoli Federico II; Italia Fil: Valverde, Claudio Fabián. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnologia. Centro de Bioquimica y Microbiologia de Suelos. Laboratorio de Fisiologia, Genetica de Bacterias Para Plantas.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The aim of this study was to investigate the physical, chemical and microbiological contamination of indoor swimming pools.Pool water specimens were collected using a plastic polypropylene sterilized bottle. The physical and chemical qualities of the waters were analyzed in terms of temperature, turbidity, pH, and free residual chlorine, with the standard methods for the examination of water. Bacteriological (routine methods) and parasitological (molecular methods) tests were carried out on pools water.The mean temperature, pH, and residual chlorine of the indoor pools were 31.2 °C, 7.6 and 1.5 mg/L, respectively. Turbidity was not observed in any of the pools. The pH and temperature values were in standard ranges in 92.3% and 15.4% of the waters of swimming pools, respectively. The prevalence rates of bacterial and amoebic contaminations of the water in the swimming pools were 53.8% and 46.2%, respectively. One pool (7.7%) was contaminated with both bacteria and amoeba.In this study, some microorganisms were identified from the water pools. Effective management of swimming pools and proper control of the physical, chemical and microbiological property of water pools can produce the healthy recreational activity.Bu çalışmanın amacı kapalı yüzme havuzlarının fiziksel, kimyasal ve mikrobiyolojik kirlenmelerini araştırmaktır.Havuz suyu örnekleri plastik polipropilen sterilize edilmiş bir şişe kullanılarak toplandı. Suların fiziksel ve kimyasal özellikleri, suyun incelenmesinde kullanılan standart yöntemler ile sıcaklık, bulanıklık, pH ve serbest artık klor açısından analiz edildi. Havuz sularında bakteriyolojik (rutin yöntemler) ve parazitolojik (moleküler yöntemler) çalışmalar yapılmıştır.Kapalı havuzların sıcaklık, pH ve artık klor ortalamaları sırasıyla 31,2 °C, 7,6 ve 1,5 mg/L idi. Havuzların hiçbirinde bulanıklık gözlenmedi. PH ve sıcaklık değerleri yüzme havuzlarının sırasıyla %92,3 ve %15,4’ünde istenilen aralıktaydı. Yüzme havuzlarında suyun bakteriyel ve amipli kirlenme sıklığı sırasıyla %53,8 ve %46,2’dir. Bir havuz (%7,7) hem bakteri hem de amip ile kirlenmiştir.Bu çalışmada, su havuzlarından bazı mikroorganizmalar tanımlanmıştır. Yüzme havuzlarının etkin yönetimi ve su havuzlarının fiziksel, kimyasal ve mikrobiyolojik özelliklerinin uygun şekilde kontrolü sağlıklı rekreasyon aktivitesini sağlayabilir.

RESUMEN Las Infecciones Asociadas a las Atenciones Sanitarias (IAAS), constituyen un serio problema de salud pública. Se describe un brote de IAAS en una Unidad de Cuidados Intensivos Neonatales de Asunción y las medidas de control implementadas. Estudio descriptivo de serie de casos, entre el 26 de marzo y el 18 de abril del 2013. Fueron utilizados datos secundarios como historias clínicas, registros de enfermería, certificados de defunción, resultados de bacteriología, registros de control de IAAS. El universo estuvo constituido por 12 neonatos, en cuatro se aislaron Pseudomona aeruginosa y en tres Klebsiella pneumoniae BLEE. Predomino el sexo masculino (6/7), la media de edad de 2 días (rango:2-45 días), la mayoría prematuros (5/7). Todos con procedimientos invasivos durante la hospitalización. La tasa global de ataque fue 58% (7/12), con una tasa de ataque para P. aeruginosa de 33 % (4/12) y para K. pneumoniae BLEE de 38 % (3/12). La mortalidad global fue 29% (2/12) y la tasa de la letalidad atribuible a la infección por P. aeruginosa fue del 50% (2/4). Las medidas de control del brote fueron el aislamiento de los pacientes infectados, una enfermera por paciente, se intensifico los cuidados de bioseguridad para procedimientos invasivos y lavado de manos; suspensión de pacientes remitidos hasta que se asegurar el corte de transmisión. Se confirmó dos brotes simultáneos con agentes etiológicos diferentes, P. aeruginosa y K. pneumoniae BLEE. Es necesario reforzar las medidas de control de infecciones y lavado correcto de manos, de manera a prevenir brotes de IAAS en la UCIN. ABSTRACT Health care-associated infections (HCAI) constitute a serious public health problem. We describe an outbreak of HCAI in a Neonatal Intensive Care Unit (NUCI) in Asunción and the implemented control measures. This was a descriptive observational study of case series, performed between March 26th and April 18th, 2013. It is based on secondary data of the NICU, such as medical charts, nursing registries, death certificates, laboratory results and infection control registry forms. The study population consisted of 12 neonates. Pseudomona aeruginosa was isolated from biological samples of four neonates while ESBL producing-Klebsiella pneumoniae was isolated from other three patients. The patients were predominantly male (6/7), the average age was 2 days (range: 2-45 days), mostly premature babies (5/7). Invasive procedures were present in all cases. The overall attack rate was 58% (7/12), with an attack rate for P. aeruginosa of 33% (4/12) and for ESBL producing-K. Pneumoniae of 38% (3/12). Overall mortality was 29% (2/12) and the lethality rate attributable to P. aeruginosa infection was 50% (2/4). Measures implemented to control the outbreak were isolation of infected patients, one nurse per patient, intensified biosafety of invasive procedures strict control on proper hand washing, and interruption of patient transfers from other hospital during the outbreak. There were two simultaneous outbreaks with two different ethological agents, P. aeruginosa and ESBL producing-K. Pneumoniae. It is necessary to reinforce infection control measures and correct hand washing, in order to prevent outbreaks of HCAI in the NICU.

Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic derivatives are organic pollutants that pose a serious health risk to human beings. In this study, a newly isolated Pseudomonas brassicacearum strain MPDS could effectively degrade PAHs and heterocyclic derivatives, including naphthalene, fluorene, dibenzofuran (DBF) and dibenzothiophene (DBT). Notably, strain MPDS is able to degrade fluorene, DBF and DBT uniquely via a lateral dioxygenation pathway, while most reported strains degrade fluorene, DBF and DBT via an angular dioxygenation pathway or co-metabolize them via a lateral dioxygenation pathway. Strain MPDS completely degraded 50 mg naphthalene (in 50 mL medium) in 84 h, and OD600 reached 1.0–1.1; while, it stabilized at OD600 0.5–0.6 with 5 mg fluorene or DBF or DBT. Meanwhile, 65.7% DBF and 32.1% DBT were degraded in 96 h, and 40.3% fluorene was degraded in 72 h, respectively. Through genomic and transcriptomic analyses, and comparative genomic analysis with another DBF degradation strain, relevant gene clusters were predicted, and a naphthalene-degrading gene cluster was identified. This study provides understanding of degradation of PAHs and their heterocyclic derivatives, as well as new insights into the lateral dioxygenation pathway of relevant contaminants.

Routine evaluation of the slaughter process is performed by the enumeration of the aerobic colony count, Enterobacteriaceae and Salmonella spp. on the carcass through destructive or non-destructive methods. With non-destructive methods, bacteria are counted from a minimum area of 100 cm2 in different sampling sites on the pork carcasses, and the results of these investigated areas are pooled to one value for the complete carcass evaluation (a total of 400 cm2). However, the composition of the bacterial community present on the different sampling areas remains unknown. The aim of the study was to characterize the microbial population present on four areas (ham, back, jowl and belly) of eight pork carcasses belonging to two different slaughterhouses through culture-dependent (Matrix-assisted laser desorption/ionization time-of-flight Mass Spectrometry MALDI-TOF MS, combined with 16S rRNA gene sequencing) and complementary culture-independent (16S rRNA amplicon sequencing) methods. The presence of Salmonella spp. and Y. enterocolitica was additionally assessed. Using MALDI-TOF MS, Staphylococcus, Pseudomonas, and Escherichia coli were found to dominate the bacterial cultures isolated from the 8 carcasses. Based on the 16S rRNA amplicon sequencing analyses however, no specific genus clearly dominated the bacterial community composition. By using this culture-independent method, the most abundant genera in microbial populations of the ham, back, jowl and belly were found to be similar, but important differences between the two slaughterhouses were observed. Thus, present data suggests that the indigenous bacterial population of individual animals is overruled by the microbial population of the slaughterhouse in which the carcass is handled. Also, our data suggests that sampling of only one carcass area by official authorities may be appropriate for the evaluation of the hygienic status of the carcasses and therefore of the slaughter process.

Pseudomonas ANT_J38B is a Gram-negative bacterium isolated from an Antarctic island. LPS was extracted using the phenol/chloroform/petroleum ether method. A mild acid hydrolysis followed by a gel filtration purification afforded the O-chain. The polysaccharide was characterized by means of chemical analyses and NMR spectroscopy. The O-chain displays a disaccharide repeating unit with the following backbone: →4)-α- l -GulpNAc3OAcAN-(1 →3)-β- d -QuipNAc-(1→ .

PURPOSE: The aim of the present study was to quantitatively assess biofilm growth on the surface of bone cements discs containing different antibiotics, including colistin and linezolid. Biofilms of methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Staphylococcus epidermidis were grown on bone cement discs for 96 h. METHODS: Biofilm amounts were measured by confocal laser microscopy using live/dead staining and dedicated software at different time intervals (48, 72, and 96 h). RESULTS: Bone cement containing vancomycin was not effective at reducing MRSA biofilm formation 96 h following bacterial inoculation. At a comparable time interval, linezolid-, clindamycin-, and aminoglycoside-loaded cement was still active against this biofilm. At the 72- and 96-h observations, S. epidermidis biofilm was present only on tobramycin and gentamicin discs. P. aeruginosa biofilms were present on cement discs loaded with colistin at all time intervals starting from the 48-h observation, whereas no biofilms were detected on tobramycin or gentamicin discs. CONCLUSION: Bone cements containing different antibiotics have variable and time-dependent windows of activity in inhibiting or reducing surface biofilm formation. The effectiveness of bone cement containing vancomycin against MRSA biofilm is questionable. The present study is clinically relevant, because it suggests that adding the right antibiotic to bone cement could be a promising approach to treat periprosthetic infections. Indeed, the antibiofilm activity of different antibiotic-loaded bone cements could be preoperatively assessed using the current methodology in two-stage exchange procedures.

Microbiological, chemical and physical parameters of minimally processed red chicory (Cichorium intybus L.) subjected to two different transformation processes were investigated. A classic ready-to-eat (RTE) process (P1) and a production without cutting (P2) were monitored during refrigerated (4 °C) storage (15 d). Total mesophilic microorganisms, total psychrotrophic microorganisms and pseudomonads were detected at the highest cell densities in all samples. Presumptive Pseudomonas population dominated the cultivable microbial community of RTE red chicory and were characterized genetically. Twenty-two randomly amplified polymorphic DNA (RAPD) types were investigated by 16S rRNA gene sequencing, resulting in members of Rahnella and Pseudomonas. The identification of Pseudomonas species was further determined by sequencing of gyrB, rpoB and rpoD genes resulting in 16 species. A highest visual quality and a lower weight loss and colour variation were registered for P2, while soluble solid, nitrate and ascorbic acid contents were not affected by processing and storage. The integrated microbiological, chemical and physical approach applied in this study demonstrated the longer shelf-life of P2 red chicory.

The importance of the plant microbiome for host fitness has led to the concept of the "plant holobiont". Seeds are reservoirs and vectors for beneficial microbes, which are very intimate partners of higher plants with the potential to connect plant generations. In this study, the endophytic seed microbiota of numerous barley samples, representing different cultivars, geographical sites and harvest years, was investigated. Cultivation-dependent and -independent analyses, microscopy, functional plate assays, greenhouse assays and functional prediction were used, with the aim of assessing the composition, stability and function of the barley seed endophytic bacterial microbiota. Associations were consistently detected in the seed endosphere with Paenibacillus, Pantoea and Pseudomonas spp., which were able to colonize the root with a notable rhizocompetence after seed germination. In greenhouse assays, enrichment with these bacteria promoted barley growth, improved mineral nutrition and induced resistance against the fungal pathogen Blumeria graminis. We demonstrated here that barley, an important crop plant, was consistently associated with beneficial bacteria inside the seeds. The results have relevant implications for plant microbiome ecology and for the holobiont concept, as well as opening up new possibilities for research and application of seed endophytes as bioinoculants in sustainable agriculture.

Introduction: Ceftolozane/tazobactam (C/T) is a new antibiotic resulting from the combination of a novel cephalosporin, structurally similar to ceftazidime, with tazobactam, a well-known beta-lactamase inhibitor. C/T remains active against extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and multi-drug resistant (MDR) P. aeruginosa, and has been recently approved for the treatment of complicated intra-abdominal infections (cIAI) and complicated urinary tract infections (cUTI). A trial on hospital-acquired pneumonia is ongoing. Areas covered: The place in therapy of C/T is delineated by addressing the following main topics: (i) antimicrobial properties; (ii) pharmacological properties; (iii) results of clinical studies. Expert commentary: C/T is approved for cIAI and cUTI. However, the drug has a special value for clinicians in any kind of infectious localization for two main reasons. The first is that C/T is especially valuable in suspected or documented severe infections due to MDR P. aeruginosa, which is not a rare occurrence in many countries. The second is that C/T may provide an alternative to carbapenems for the treatment of infections caused by ESBL-producers, thus allowing a carbapenem-sparing strategy. Reporting of off-label use is mandatory to increase the body of evidence and the clinicians’ confidence in using it for indications other than cIAI and cUTI.

The present work was carried out to investigate the safety aspects of minimally processed red chicory (Cichorium intybus L., family Asteraceae) regarding the antibiotic resistance of Pseudomonas Migula, 1894 populations (Bacteria Pseudomonadaceae). The Pseudomonas strains tested for their characteristics were previously isolated from experimental monovarietal salads prepared with two different processes, a classic ready-to-eat (RTE) process and a process with entire leaves, and stored under refrigeration (4 °C) up to 15 days from production. Due to their dominance over the microbial community, Pseudomonas strains were better characterised for their undesirable features that might be exerted on the health of consumers. To this purpose, the 21 dominant Pseudomonas strains were subjected to the antimicrobial resistance test, applying the antibiotics commonly administered to combat intestinal bacteria responsible for human infections. The results revealed a certain sensibility to almost all the antibiotics diffused among these bacteria, with the exception of ampicillin, amoxicillin, and chloramphenicol. If, on one hand, this study has found that, generally, Pseudomonas are not related to the dissemination of the majority of antibiotics used for hospitalized patients, on the other hand, it poses the attention to this microbial group regarding ampicillin and amoxicillin.

Pseudomonas infections are common among hospitalized, immunocompromised, and chronic lung disease patients. These infections are recalcitrant to common antibacterial therapies due to inherent antibiotic resistance. To meet the need of new anti- Pseudomonas drugs, a sensitive, homogenous, and robust assay was developed with the aim of identifying inhibitors of acyl-coenzyme A synthetases (ACSs) from Pseudomonas. Given the importance of fatty acids for in vivo nutrition of Pseudomonas, such inhibitors might have the potential to reduce the bacterial fitness during infection. The assay, based on a coupled reaction between the Pseudomonas spp. ACS and the firefly luciferase, allowed the identification of three classes of inhibitors by screening of a diverse compound collection. These compounds were confirmed to reversibly bind ACS with potencies in the micromolar range. Two classes were found to compete with acyl-coenzyme A, while the third one was competitive with fatty acid binding. Although these compounds inhibit the bacterial ACS in cell-free assays, they show modest or no effect on Pseudomonas growth in vitro.

Pseudomonas corrugata and P. mediterranea are soil inhabitant bacteria, generally living as endophytes on symptomless plants and bare soil, but also capable of causing plant diseases. They share a similar genome size and a high proteome similarity. P. corrugata produces many biomolecules which play an important role in bacterial cell survival and fitness. Both species produce different medium-chain-length PHAs (mcl-PHAs) from the bioconversion of glycerol to a transparent film in P. mediterranea and a sticky elastomer in P. corrugata. In this work, using RNA-seq we investigated the transcriptional profiles of both bacteria at the early stationary growth phase with glycerol as the carbon source. Quantitative analysis of P. mediterranea transcripts versus P. corrugata revealed that 1756 genes were differentially expressed. A total of 175 genes were significantly upregulated in P. mediterranea, while 217 were downregulated. The largest group of upregulated genes was related to transport systems and stress response, energy and central metabolism, and carbon metabolism. Expression levels of most genes coding for enzymes related to PHA biosynthesis and central metabolic pathways showed no differences or only slight variations in pyruvate metabolism. The most relevant result was the significantly increased expression in P. mediterranea of genes involved in alginate production, an important exopolysaccharide, which in other Pseudomonas spp. plays a key role as a virulence factor or in stress tolerance and shows many industrial applications. In conclusion, the results provide useful information on the co-production of mcl-PHAs and alginate from glycerol as carbon source by P. mediterranea in the design of new strategies of genetic regulation to improve the yield of bioproducts or bacterial fitness.

The phenanthrene (PHE) degradation by a halotolerant bacterial consortium enriched from production water of Sercina oilfield in Tunisia was investigated. The consortium PHMM utilized PHE (200 mg/L), as a sole carbon source, in the presence of a wide range of NaCl concentrations, from 1 to 5% (w/v). The maximum growth rate was obtained at 500 mg/L of PHE. A PHE metabolism was assayed by using FTIR, UV and GC–MS analyses. Results revealed that the consortium PHMM metabolized PHE via protochatechuate pathway since intermediates such as naphthalenol and phthalic acid were detected. Phylogenetic analysis showed that the adapted consortium PHMM was composed by two dominant bacterial strains, identified as Pseudomonas sp. (strain PH1) and Staphylococcus sp. (strain PH2). All the results indicated that the microorganisms from the Tunisian oilfield have a promising application in bioremediation of petrochemical contaminated environments and could be potentially useful for the study of PAHs biodegradation.

The aim of this research was evaluate the power of bioremediation of the fungus Trichoderma sp and the bacteria Pseudomonas fluorescens in a sample of soil contaminated by hydrocarbons, in order to reduce the TPH (total polycyclic hydrocarbons) in soil. This project was completed in two phases: the field work consisted of soil sampling and the laboratory work consisted of installation of an assay with a DBCA system with 4 treatments (T0: control soil, T1: Soil + Trichoderma sp, T2: Soil + Pseudomonas fluorescens and T3 : Soil with Pseudomonas fluorescens + Trichoderma sp ) and 4 repetitions with controlled environmental conditions such as pH, temperature, electrical conductivity and moisture; the physico-chemical and TPH analyzes was performed at beginning and end of the assay for 3 months. The soil at beginning of the assay had macro and micro elements which are essential for microorganisms to degrade hydrocarbons. The initial TPH contamination in soil was 42070.3 mg / kg, and at the end of the assay the T1, T2 and T3 obtained an effective remediation, settling down within the permissible limits of RAOHE (environmental regulations hydrocarbon activities); demonstrating that all treatments work independently and in a consortium. The T3 (consortium) was the treatment that degraded more amount of hydrocarbons with a value of 379.2 mg / kg, the reason was because both microorganisms had the necessary mechanisms to degrade the hydrocarbon molecules, showing that bioremediation is an ecological and effective process for the degradation of hydrocarbons. En la presente investigación se evaluó el poder biorremediador del hongo Trichoderma sp y la bacteria Pseudomonas fluorescens en un suelo contaminado por hidrocarburos, con el objetivo de disminuir los TPH (hidrocarburos totales policíclicos) en el suelo. Este proyecto se efectuó en dos fases: la fase de campo consistió en el muestreo de suelo y la fase de laboratorio consistió en la instalación del ensayo con un sistema DBCA de 4 tratamientos, (T0: Suelo testigo, T1: Suelo + Trichoderma sp, T2: Suelo + Pseudomonas fluorescens y T3: Suelo con Trichoderma sp + Pseudomonas fluorescens) y 4 repeticiones con condiciones ambientales controladas como: pH, temperatura, conductividad eléctrica y humedad; se realizaron los análisis físico químicos y TPH al inicio y al final del ensayo durante 3 meses. El suelo al inicio del ensayo presentó macro y micro elementos indispensables para que los microrganismos puedan degradar los hidrocarburos. La contaminación con TPH inicial en el suelo fue 42070.3 mg/kg, al final del ensayo los tratamientos T1, T2 y T3 obtuvieron una remediación eficaz, situándose dentro de los límites permisibles del RAHOE (reglamento ambiental de actividades hidrocarburíferas); se demostró que los tratamiento funcionan de forma independiente y en consorcio, siendo el T3 (consorcio) el cual degradó más cantidad de hidrocarburo llegando a 379.2 mg/kg, debido a que ambos microrganismos gozan de los mecanismos necesarios para degradar las moléculas de hidrocarburos, demostrándose que la biorremediación es una proceso ecológico y efectivo para la degradación de hidrocarburos.

Introduction Although bronchiectasis particularly affects people ≥65 years of age, data describing clinical characteristics of the disease in this population are lacking. This study aimed at evaluating bronchiectasis features in older adults and elderly, along with their clinical outcomes. Methods This was a secondary analysis of six European databases of prospectively enrolled adult outpatients with bronchiectasis. Bronchiectasis characteristics were compared across three study groups: younger adults (18–65 years), older adults (66–75 years), and elderly (and ≥76 years). 3-year mortality was the primary study outcome. Results Among 1258 patients enrolled (median age: 66 years; 42.5% males), 50.9% were ≥65 years and 19.1 ≥ 75 years old. Elderly patients were more comorbid, had worse quality of life and died more frequently than the others. Differences were detected among the three study groups with regard to neither the etiology nor the severity of bronchiectasis, nor the prevalence of chronic infection with P. aeruginosa. In multivariate regression model, age (OR: 1.05; p-value