Blue-light-dependent inhibition of twitching motility in Acinetobacter baylyi ADP1: additive involvement of three BLUF-domain-containing proteins

Twitching motility in Acinetobacter baylyi ADP1 is inhibited by moderate intensities of blue light in a temperature-dependent manner (maximally at 20 °C). We analysed the involvement of four predicted blue-light sensing using flavin (BLUF)-domain-containing proteins encoded in the genome of this strain in the twitching motility phenotype. All four genes were expressed both in light and in darkness. A phylogenetic tree showed that one BLUF domain, ACIAD2110, grouped separately from the other three (ACIAD1499, ACIAD2125 and ACIAD2129). Individual knockout mutants of the latter three, but not of ACIAD2110, fully abolished the light dependency of the twitching motility response. Quantitative analysis of transcript level of the three genes showed a decreased expression in the light, with dark/light ratios of 1.65±0.28, 1.79±0.21 and 2.69±0.39, for ACIAD2125, ACIAD2129 and ACIAD1499, respectively. Double and triple knockouts of ACIAD1499, ACIAD2125 and ACIAD2129 confirmed the same phenotype as the corresponding single knockouts. Complementation of all the single knockouts and the triple knockout mutants with any of the three BLUF-domain-encoding genes fully restored the inhibition of twitching motility by blue light that is observed in the wild-type strain. A. baylyi ADP1 therefore shows a high degree of redundancy in the genes that encode BLUF-containing photoreceptors. Moreover, all plasmid-complemented strains, expressing any of the BLUF proteins irrespective of the specific set of deleted photoreceptors, displayed increased light-dependent inhibition of twitching motility, as compared to the wild-type (P<0.001). We conclude that the three genes ACIAD1499, ACIAD2125 and ACIAD2129 are jointly required to inhibit twitching motility under moderate blue-light illumination.Fil: Bitrian, Mariana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Gonzalez, Rodrigo Horacio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Paris, Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquimicas de Buenos Aires; ArgentinaFil: Hellingwerf, Klaas. University Of Amsterdam; Países BajosFil: Nudel, Berta Clara. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentin

Identification of virulence markers in clinically relevant strains of Acinetobacter genospecies

Nine Acinetobacter strains from patients and hospital environment were analyzed for virulence markers, quorum sensing signal production, and the presence of luxI and luxR genes. The strains had several properties in common: growth in iron limited condition, biofilm formation, and no active protease secretion. Significantly higher catechol production was determined in patient isolates (P &lt; 0.03), but other invasiveness markers, such as lipase secretion, amount of biofilm, cell motility, antibiotic resistance, and hemolysin production, showed large variability. Notably, all members of the so-called A. calcoaceticus-A. baumannii complex, regardless of whether the source was a patient or environmental, secreted medium to long-chain N-acyl homoserine lactones (AHL) and showed blue light inhibition of cell motility. In these strains, a luxI homologue with a homoserine lactone synthase domain and a luxR putative regulator displaying the typical AHL binding domain were identified

Primary malignant PEComa of the mandible. Report of an unusual case

Malignant PEComa is a rare entity that usually origins at visceral, retroperitoneal and abdominopelvic sites. In the present paper, we describe an extremely unusual manifestation of malignant PEComa involving the mandible in a 48 years-old female patien

Estado actual de las investigaciones en el sitio Arroyo Seco 2 (Partido de Tres Arroyos, provincia de Buenos Aires, Argentina)

Fil: Politis, Gustavo Gabriel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; ArgentinaFil: Gutiérrez, María Amelia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; ArgentinaFil: Scabuzzo, Clara. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; Argentin

Congenital cytomegalovirus, parvovirus and enterovirus infection in Mozambican newborns at birth: A cross-sectional survey

BACKGROUND: Congenital cytomegalovirus (cCMV) infection is the most prevalent congenital infection acquired worldwide, with higher incidence in developing countries and among HIV-exposed children. Less is known regarding vertical transmission of parvovirus B19 (B19V) and enterovirus (EV). We aimed to assess the prevalence of CMV, B19V and EV vertical transmission and compare results of screening of congenital CMV obtained from two different specimens in a semirural Mozambican maternity. METHODS: A cross sectional study was conducted among pregnant mothers attending Manhica District Hospital upon delivery. Information on maternal risk factors was ascertained. Dried umbilical cord (DUC) samples were collected in filter paper for CMV, B19V and EV detection by real-time polymerase chain reaction (RT-PCR), and nasopharyngeal aspirates (NPA) to test for CMV by RT-PCR. Maternal blood samples and placental biopsy samples were also obtained to investigate CMV maternal serology, HIV status and immunopathology. RESULTS: From September 2014 to January 2015, 118 mothers/newborn pairs were recruited. Prevalence of maternal HIV infection was 31.4% (37/118). CMV RT-PCR was positive in 3/115 (2.6%) of DUC samples and in 3/96 (6.3%) of NPA samples obtained from neonates. The concordance of the RT-PCR assay through DUC with their correspondent NPA sample was moderate (Kappa = 0.42 and p<0.001. No differences on cCMV prevalence were found among HIV-exposed and unexposed. All (100%) mothers were seropositive for CMV IgG. RT-PCR of EV and B19V in DUC were both negative in all screened cases. No histological specific findings were found in placental tissues. No risk factors associated to vertical transmission of these viral infections were found. CONCLUSIONS: This study indicates the significant occurrence of vertical transmission of CMV in southern Mozambique. Larger studies are needed to evaluate the true burden, clinical relevance and consequences of congenital infections with such pathogens in resource-constrained settings

In vitro and in planta assay of the phytosanitary activity of zinc(II) complexes with thiosemicarbazone ligands.

[Resumen] El aumento de la población mundial, y, por tanto, el incremento en la demanda de alimentos obtenidos mediante el monocultivo fomentan la aparición de epidemias de enfermedades fúngicas que provocan pérdidas importantes en los cultivos. Esto, y la aparición de cepas de ciertos patógenos resistentes a los pesticidas clásicos, hace necesario un continuo desarrollo de nuevos productos fitosanitarios. Debido a las interesantes actividades biológicas que presentan las tiosemicarbazonas y sus complejos metálicos, en el presente Trabajo de Fin de Grado se ha estudiado la potencial actividad fitosanitaria de algunos compuestos de estos grupos. Por un lado, se ha medido la capacidad de algunas tiosemicarbazonas y sus complejos de zinc(II) para inhibir el crecimiento de los patógenos Botrytis cinerea y Phytophthora capsici. Por otro lado, se ha determinado la capacidad fitosanitaria in planta de esos compuestos usando Cucurbita pepo como huésped de los patógenos anteriores. Estos experimentos mostraron diferencias en la inhibición del crecimiento en función de los compuestos ensayados y del patógeno utilizado. De hecho, los resultados de un complejo en concreto mostraron evidencias de resistencia inducida en planta.[Resumo] O aumento da poboación mundial, e, polo tanto, o incremento na demanda de alimentos obtidos mediante o monocultivo fomentan a aparición de epidemias de enfermidades fúnxicas que provocan perdas importantes nos cultivos. Isto, e a aparición de cepas de certos patóxenos resistentes aos pesticidas clásicos, fai necesario un continuo desenvolvemento de novos produtos fitosanitarios. Debido ás interesantes actividades biolóxicas que presentan as tiosemicarbazonas e os seus complexos metálicos, no presente Traballo de Fin de Grao estudouse a potencial actividade fitosanitaria dalgúns compostos destes grupos. En primeiro lugar, mediuse a capacidade dalgunhas tiosemicarbazonas e os seus complexos de zinc(II) para inhibir o crecemento dos patóxenos Botrytis cinerea e Phytophthora capsici. En segundo lugar, determinouse a capacidade fitosanitaria in planta deses compostos usando Cucurbita pepo como hóspede dos patóxenos anteriores. Estes experimentos mostraron diferenzas na inhibición do crecemento dependendo dos compostos ensaiados e do patóxeno utilizado. De feito, os resultados dun complexo en concreto mostraron evidencias de resistencia inducida na planta.[Abstract] The increase in world population and, therefore, the rise in the demand for food obtained through monoculture triggers the appearance of epidemics of fungal diseases that cause significant crop losses. This fact, and the appearance of pathogens strains resistant to classic pesticides, makes necessary to continuously develop new phytosanitary products. Due to the interesting biological activities of thiosemicarbazones and their metal complexes, in this Final Degree Project we have studied the potential phytosanitary activity of some compounds of these groups. On one hand, the capacity of some thioemicarbazones and their zinc(II) complexes for inhibiting the growth of the pathogens Botrytis cinerea and Phytophthora capsici has been measured. On the other side, the in planta phytosanitary capacity of these compounds has been determined using Cucurbita pepo as a host for the pathogens mentioned above. These experiments showed differences in growth inhibition depending on the compounds tested and the pathogen used. In fact, the results for one particular complex showed signs of induced resistance in the plant.Traballo fin de grao (UDC.CIE). Bioloxía. Curso 2022/202

Percepção de Obstáculos à Inovação na Indústria Brasileira de Transformação

This article aims to identify the perception of the Brazilian manufacturing industry about the main obstacles to innovation. We used in the research "microdata” from the three years National Innovation Research – PINTEC 2011 (IBGE, 2013). Confirmed the results that innovative firms are more likely to report barriers to innovation that non-innovative companies. It is evident also that four factors had higher perceived importance as harmful to innovative activities in that sector: 1) high innovation costs; 2) excessive economic risk; 3) lack of qualified personnel and 4) lack of funding.Este artigo tem como objetivo identificar a percepção da indústria brasileira de transformação acerca dos principais obstáculos à inovação. Foram usados na pesquisa os “microdados’ do triênio 2009-10-11, da Pesquisa de Inovação – PINTEC 2011 (IBGE, 2013). Confirma-se nos resultados que as empresas inovadoras são mais propensas a relatar obstáculos à inovação que as empresas não inovadoras. Evidencia-se ainda que quatro fatores apresentaram maior percepção de importância como prejudiciais às atividades inovativas no referido setor: 1) elevados custos de inovação; 2) risco econômico excessivo; 3) falta de pessoal qualificado e 4) escassez de fontes de financiament