Paramagnetic tools for the structural analysis of high molecular weight proteins

   Paramagnetic effects provide important structural and dynamic information of biomolecules. However, the attachment of lanthanides through small chelating organic molecules to proteins (the most common way to obtain paramagnetic effects) requires single cysteine mutants, optimization of the tagging reaction and previous knowledge of the three-dimensional structure of the target to select proper attachment sites. In this work was developed a new method that relieves most of these disadvantages: the lanthanide is not directly attached to the target protein, but instead to a "reporter" protein that binds and transmits paramagnetic information to the target protein.     In this thesis is shown that the attachment of a lanthanide in different locations on the surface of the reporter protein PDZ allows measuring residual dipolar couplings and pseudo contact shifts from several independent molecular alignments on any target. This is shown for ubiquitin and the maltose binding protein. The fusion of a 7-residue PDZ recognition peptide to the C-terminus of the target proteins is the only necessary modification to obtain the paramagnetic restraints. Therefore, this method allows recording a large amount of paramagnetic information from orientationally independent molecular alignments in proteins. Moreover, it is not necessary to have previous knowledge of the three-dimensional structure of the targets

Effectiveness of treatments in Neuromyelitis optica to modify the course of disease in adult patients. Systematic review of literature.

El trastorno del espectro de la neuromielitis óptica (NMOSD) es una enfermedad inflamatoria, que se manifiesta principalmente como episodios recurrentes de neuritis o mielitis óptica que causan una discapacidad importante. El diagnóstico temprano y el pronto inicio de la terapia inmunosupresora son cruciales para reducir las recaídas, la discapacidad y la mortalidad. Aunque hay pocos ensayos controlados aleatorios prospectivos, varios medicamentos han demostrado ser efectivos y seguros. La azatioprina y el rituximab representan el estándar de atención y se utilizan como agentes de tratamiento de primera línea en todo el mundo. Sin embargo, estudios recientes han revelado nuevas terapias, como los anticuerpos monoclonales. Para hacer recomendaciones de tratamiento y pautas de manejo, es imperativo definir un estándar de atención adecuado.Neuromyelitis Optica spectrum disorder (NMOSD) is an inflammatory disease, which manifests mostly as recurrent episodes of optic neuritis or myelitis that cause important disability. Early diagnosis and prompt initiation of immunosuppressive therapy are crucial in reducing relapses, disability, and mortality. Even though, there are few prospective randomized controlled trials, several drugs have proved to be both effective and safe. Azathioprine and Rituximab represent the standard of care and are used as first-line treatment agents worldwide. However, recent studies have unveiled new therapies, such as monoclonal antibodies. To make treatment recommendations and management guidelines, it is imperative to define an appropriate standard of care.N/

Evolution of substrate specificity in a recipient's enzyme following horizontal gene transfer

Despite the prominent role of horizontal gene transfer (HGT) in shaping bacterial metabolism, little is known about the impact of HGT on the evolution of enzyme function. Specifically, what is the influence of a recently acquired gene on the function of an existing gene? For example, certain members of the genus Corynebacterium have horizontally acquired a whole L-tryptophan biosynthetic operon, whereas in certain closely related actinobacteria, for example, Mycobacterium, the trpF gene is missing. In Mycobacterium, the function of the trpF gene is performed by a dual-substrate (βα)8 phosphoribosyl isomerase (priA gene) also involved in L-histidine (hisA gene) biosynthesis. We investigated the effect of a HGT-acquired TrpF enzyme upon PriA’s substrate specificity in Corynebacterium through comparative genomics and phylogenetic reconstructions. After comprehensive in vivo and enzyme kinetic analyses of selected PriA homologs, a novel (βα)8 isomerase subfamily with a specialized function in L-histidine biosynthesis, termed subHisA, was confirmed. X-ray crystallography was used to reveal active-site mutations in subHisA important for narrowing of substrate specificity, which when mutated to the naturally occurring amino acid in PriA led to gain of function. Moreover, in silico molecular dynamic analyses demonstrated that the narrowing of substrate specificity of subHisA is concomitant with loss of ancestral protein conformational states. Our results show the importance of HGT in shaping enzyme evolution and metabolism

Maternal vaccination against COVID-19 and neonatal outcomes during Omicron: INTERCOVID-2022 study

Background: In early 2023, when Omicron was the variant of concern, we showed that vaccinating pregnant women decreased the risk for severe COVID-19-related complications and maternal morbidity and mortality. Objective: This study aimed to analyze the impact of COVID-19 during pregnancy on newborns and the effects of maternal COVID-19 vaccination on neonatal outcomes when Omicron was the variant of concern. Study design: INTERCOVID-2022 was a large, prospective, observational study, conducted in 40 hospitals across 18 countries, from November 27, 2021 (the day after the World Health Organization declared Omicron the variant of concern) to June 30, 2022, to assess the effect of COVID-19 in pregnancy on maternal and neonatal outcomes and to assess vaccine effectiveness. Women diagnosed with laboratory-confirmed COVID-19 during pregnancy were compared with 2 nondiagnosed, unmatched women recruited concomitantly and consecutively during pregnancy or at delivery. Mother-newborn dyads were followed until hospital discharge. The primary outcomes were a neonatal positive test for COVID-19, severe neonatal morbidity index, severe perinatal morbidity and mortality index, preterm birth, neonatal death, referral to neonatal intensive care unit, and diseases during the neonatal period. Vaccine effectiveness was estimated with adjustment for maternal risk profile. Results: We enrolled 4707 neonates born to 1577 (33.5%) mothers diagnosed with COVID-19 and 3130 (66.5%) nondiagnosed mothers. Among the diagnosed mothers, 642 (40.7%) were not vaccinated, 147 (9.3%) were partially vaccinated, 551 (34.9%) were completely vaccinated, and 237 (15.0%) also had a booster vaccine. Neonates of booster-vaccinated mothers had less than half (relative risk, 0.46; 95% confidence interval, 0.23-0.91) the risk of being diagnosed with COVID-19 when compared with those of unvaccinated mothers; they also had the lowest rates of preterm birth, medically indicated preterm birth, respiratory distress syndrome, and number of days in the neonatal intensive care unit. Newborns of unvaccinated mothers had double the risk for neonatal death (relative risk, 2.06; 95% confidence interval, 1.06-4.00) when compared with those of nondiagnosed mothers. Vaccination was not associated with any congenital malformations. Although all vaccines provided protection against neonatal test positivity, newborns of booster-vaccinated mothers had the highest vaccine effectiveness (64%; 95% confidence interval, 10%-86%). Vaccine effectiveness was not as high for messenger RNA vaccines only. Vaccine effectiveness against moderate or severe neonatal outcomes was much lower, namely 13% in the booster-vaccinated group (all vaccines) and 25% and 28% in the completely and booster-vaccinated groups, respectively (messenger RNA vaccines only). Vaccines were fairly effective in protecting neonates when given to pregnant women ≤100 days (14 weeks) before birth; thereafter, the risk increased and was much higher after 200 days (29 weeks). Finally, none of the neonatal practices studied, including skin-to-skin contact and direct breastfeeding, increased the risk for infecting newborns. Conclusion: When Omicron was the variant of concern, newborns of unvaccinated mothers had an increased risk for neonatal death. Neonates of vaccinated mothers had a decreased risk for preterm birth and adverse neonatal outcomes. Because the protective effect of COVID-19 vaccination decreases with time, to ensure that newborns are maximally protected against COVID-19, mothers should receive a vaccine or booster dose no more than 14 weeks before the expected date of delivery

Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications

The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium’s collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form

Prevalence of neuromyelitis optica spectrum disorder in Colombia : analysis of the official Ministry of Health administrative registry

El trastorno del espectro de la neuromielitis óptica (NMOSD) es una entidad rara con eventos desmielinizantes inflamatorios graves del sistema nervioso central con secuelas debilitantes. Su prevalencia global oscila entre 0,5 y 4/100.000 individuos, con variaciones según región y etnia. América Latina carece de datos epidemiológicos sobre la enfermedad y se desconoce la prevalencia en Colombia. Objetivo La prevalencia de NMOSD en Colombia se estimó entre 2017 y 2021 utilizando la base de datos administrativa oficial del Ministerio de Salud (SISPRO). Métodos Este es un estudio retrospectivo observacional, transversal, que utiliza datos entre enero de 2017 y diciembre de 2021 en la base de datos SISPRO utilizando el código de Clasificación Internacional de Enfermedades para NMOSD G36.0. La prevalencia por género, edad y distribución geográfica se estimó utilizando estadísticas oficiales del gobierno para 2019. Se utilizó la población estándar de la Organización Mundial de la Salud (OMS) para ajustar mediante el método directo. Resultados 2.650 pacientes fueron diagnosticados con NMOSD; la edad promedio fue de 44,9 años con una prevalencia general no ajustada de 5,3/100.000 personas, mayor para las mujeres (7,8) que para los hombres (2,8). No se observaron cambios significativos (de 5,3 a 5,4) después de ajustarse al estándar de la OMS. Conclusión Según este estudio, Colombia tiene una de las tasas de prevalencia de NMOSD más altas en América Latina; se necesitan más estudios para dilucidar los factores contribuyentes.Q1Q1Neuromyelitis optica spectrum disorder (NMOSD) is a rare entity with severe inflammatory demyelinating events of the central nervous system with debilitating sequelae. Its global prevalence ranges between 0.5 and 4/100,000 individuals, with variations by region and ethnicity. Latin America lacks epidemiological data on the disease, and Colombian prevalence is unknown. Objective Prevalence of NMOSD in Colombia was estimated between 2017 and 2021 using the official Ministry of Health administrative database (SISPRO). Methods This is an observational, cross-sectional retrospective study, using data between January 2017 and December 2021 in the SISPRO database using the International Classification of Disease code for NMOSD G36.0. Prevalence by gender, age and geographic distribution was estimated using official government statistics for 2019. World Health Organization (WHO) standard population was used to adjust using the direct method. Results 2,650 patients were diagnosed with NMOSD; the average age was 44.9 years with an overall unadjusted prevalence of 5.3/100,000 individuals, higher for females (7.8) than for males (2.8). No significant changes (from 5.3 to 5.4) were seen after adjusting to the WHO standard. Conclusion According to this study Colombia has one of the highest prevalence rates of NMOSD in Latin America, further studies are needed to elucidate the contributing factorsRevista Internacional - IndexadaS

Small molecule-induced soluble oligomers of α-synuclein with helical structure.

Accumulation of α-synuclein (αSyn) aggregates constitutes the hallmark of synucleinopathies including Parkinson's disease. However, many steps from the innocuous, monomeric αSyn toward misfolded oligomers and fibrillar species remain unclear. Here, we show that αSyn can form in solution α-helical oligomers, which are off-pathway to fibrillization, through interaction with the tetrapyrrole phthalocyanine tetrasulfonate. Chemical cross-linking combined with mass spectrometry reveals a large number of intermolecular cross-links along the entire αSyn sequence in the phthalocyanine tetrasulfonate-stabilized αSyn oligomers. Our study suggests that stabilization of structured oligomers by small molecules provides a viable strategy to interfere with αSyn fibrillization