Development of vectors and specialized Streptomyces strains for functional metagenomics

Motivation: Antimicrobial resistance (AMR) are one of the most important existing threats to public health aggravated by theoveruse of antimicrobials. It is estimated that the mortality from drug-resistance infections would increase up to 10 millions by2050. One of the major hurdles in microbial ecology is the inability to culture most of the microbial diversity present in ecosystemsunder laboratory conditions. The molecular analysis strategies used to examine the microbial community DNA, also known asthe metagenome, have been denoted as metagenomics techniques. With the use of functional metagenomics we are focus ourefforts on searching new antimicrobials. For the expression of genes from metagenomics DNA, Escherichia coli is the host mostused for function-based screening. However, the potential of Streptomyces as a surrogate host for the production of heterologousproteins has shown to be interesting for expression of proteins that are difficult to express in other bacterial host system.Methods: Basing on previous work, we are using a construction of specialized vectors with modified heterologous expressionsystem that incorporate viral components. The construction consist in the T7 RNA-polymerase gene (gene1), synthesized witha codon optimization for Streptomyces, that encodes the phage RNA-polimerase which is insensitive to many of the bacterialtermination signals. The gene1 expression is regulated by a inducible expression system based on PnitA-NitR regulatory system.To test that our system work properly, we have introduced in the cosmid for the metagenomic library construction, which isreplicative in Streptomyces, a reporter gene (xylE) whose gene product is a catechol dioxygenase which converts the colourlesssubstrate catechol to an intensely yellow oxidation product.Results: This part of the project aims to evaluate the efficience of heterologous expression measuring the catechol dioxygenaseactivity in solid and liquid media. In solid media we have seen that the Streptomyces colonies turned yellow when catechol wasapplied indicating that the expression system is working efficiently. The main objective of this project is to develop a metagenomiclibrary, with an improved heterologous expression, from DNA originating in several strains of Streptomyces in order to searchfor new antimicrobial resistance

Electrocatalytic properties of spray-drying-synthesized cobalt or nickel phosphonate-derived materials.

As a class of coordination polymers (CPs), metal phosphonates (MPs) are constructed by coordination bonds connecting metal sites and phosphonate (RPO32−) ligands, where the metal sites are dispersed uniformly at the atomic level. This feature facilitates the construction of OER/HER transition metal phosphide (TMP) pre-catalysts, making them very attractive precursors of Non-Precious Metal Electrocatalysts (NPMCs) [1, 2] In this work, we report the synthesis and crystal structures of several transition-metal phosphonates derived from the phosphonopropionic acid (PPA), [FexM1-x(HO3PCH2CH2COO)2(H2O)2; M=Co2+ or Ni2+; x= 0, 0.2]. These solids have been prepared for the first time by spray-drying synthesis directly on carbon paper (CP) (Scheme 1). Pyrolysis of spray-dried materials in 5%-H2/Ar led to TMP-based energy-conversion electrocatalysts. As compared with other conventional procedures, this synthetic methodology allowed to improve the water-splitting activity.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. PID2019-110249RB-I00/AEI/10.13039/501100011033 TED2021–129836B-I00/AEI/10.13039/501100011033/Uni´on Europea NextGenerationEU/PRTR (MICIU, Spain) P20-00416 (Junta de Andalucia, Spain/FEDER

Electrocatalytic properties of cobalt phosphides and pyrophosphates derived from phosphonate-based-MOFs

As a class of coordination polymers (CPs), metal phosphonates (MPs) are constructed by coordination bonds connecting metal sites and phosphonate (RPO32−) ligands, where the metal sites are dispersed uniformly at the atomic level. This feature facilitates the construction of metalphosphorous-based/nano-carbon composites by one-step pyrolysis, making them very attractive precursors of Non-Precious Metal Electrocatalysts (NPMCs) [1, 2] In this work, we report the synthesis, characterization and electrochemical properties of three cobalt(II) coordination polymers erived from the N,N-bis(phosphonomethyl)glycine (BPMGLY), Co(C4H9O8NP2·nH2O (n=2-4). These MPs, with different frameworks according to the crystallographic data, are used as precursors of new NPMCs by pyrolytic treatment under 5%-H2/Ar at different temperatures. The electrochemical behavior of the resulting compounds, mainly crystalline cobalt pyrophosphates and/or phosphides, is fully investigated regarding to the Oxygen Evolution and Reduction Reactions (OER and ORR, respectively) as well as Hydrogen Evolution Reaction (HER). In general, cobalt phosphides (CoP) derived from compound Co-BPMGLY-I (n=4), displayed better performances for the HER with an overpotential of 156 mVUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Implementing Pair Distribution Function analysis to rationalize the water-splitting activity of Co-phosphonate-derived electrocatalysts.

Pair Distribution Function analysis (PDF) is a total X-ray scattering technique, including the diffuse scattering and the Bragg diffraction. Thus, PDF can be used to characterize structural domains of amorphous solids to investigate local order/properties correlations [1]. Herein, a follow-up of the chemical evolution of pyrophosphate- or phosphide-based Fe/Co electrocatalysts is carried out by synchrotron PDF analysis. The catalysts were prepared from the metal (R,S) 2-hydroxyphosphonoacetates by pyrolysis in N2 (500 ºC and 700 ºC) or 5%-H2/Ar (800 ºC) and studied toward the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Comparison of PDF patterns of the amorphous (500 ºC) and the semicrystalline Fe/Co pyrophosphates (700 ºC) showed that the local order of the amorphous solid is composed of nanoclusters of ~ 7 Å (Figure 1). In contrast, the PDF pattern of the Fe/Co phosphide (800 ºC) is formed by a mixed of the crystalline phases o-Co2P and o-CoP. Differential PDF (d-PDF) analysis of the spent catalysts revealed that, irrespectively of the amorphous or crystalline nature, all pyrolyzed solids transformed under OER operation into biphasic CoO(OH), composed of discrete clusters with size ≤ 20 ÅUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Synthesis, structural characterization and electrocatalytic properties of cobalt phosphides and pyrophosphates derived from glyphosine

Póster presentado en el XXX Simposio del GE3CMetal phosphonates (MPs), a subclass of coordination polymers, result from the bonding of phosphonic acids (RPO32-) with metal ions, giving rise to an uniformly dispersion of the metal sites at the atomic scale. This characteristic allows the preparation of metal-phosphorous-based nano-carbon composites by a simple one-step pyrolysis, what makes them very attractive precursors of Non-Precious Metal Catalysts (NPMCs). Herein, we report the synthesis, characterization and electrochemical properties of three cobalt(II) coordination polymers derived from the glycine-N,N-bis(methylenenphosphonic acid) (BPMGLY), with formula [Co(C4H9O8NP2(H2O)2]·nH2O (n=0, 2). In contrast with the zero-dimensional structure of [Co(C4H9O8NP2(H2O)2]·2H2O (Co-BPMGLY-I), the two new polymorphs synthesized, Co(C4H9O8NP2(H2O)2 (Co-BPMGLY-II and Co-BPMGLY-III), whose structures have been solved from powder diffraction data, show two-dimensional frameworks with different connectivity between the Co2+ ions and the ligand within the sheets. These MPs were used as precursors of NPMCs by pyrolyzing them under 5%-H2/Ar at different temperatures. The electrochemical behavior of the resulting compounds, mainly crystalline cobalt pyrophosphates and/or phosphides, is fully studied regarding to the Oxygen Evolution and Reduction Reactions (OER and ORR, respectively) as well as Hydrogen Evolution Reaction (HER). Cobalt phosphide (CoP) derived from Co-BPMGLY-I displayed the best results, showing an overpotential of 156 mV for HER.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Proyectos nacionales MAT2016-77648-R y PID2019-110249RB-I0

Applications of N,N-bis(phosphonomethyl)glycine-derived Sn4+ or Co2+ phosphonates as proton conductors or energy-conversion electrocatalysts.

Metal phosphonates (MPs), a subclass of coordination polymers, may exhibit acidic groups such as POH, SO3H, COOH, N+-H, etc. Combining these features with electrocatalytically active transition metals, make them highly appealing in the field of fuel cells and electrolysers, as potential proton conductors and/or precursors of electrocatalysts [1,2]. Herein, we investigate the synthesis, characterization and applications of a series of Co2+ and Sn4+ phosphonates derived from glycine-N,N-bis(methylenenphosphonic acid) (BPMGLY). In the case of the tin derivative, an amorphous compound, Sn(C4H11O8NP2)0.75Cl2.5(H2O)2.5 (Sn4+- BPMGLY), was obtained by hydrothermal synthesis. Its pyrolytic treatment at 700 ºC in air led to an amorphous pyrophosphate, (Sn4+- BPMGLY@700). Regarding cobalt phosphonates, three crystalline phases with composition [Co(C4H9O8NP2(H2O)2]·nH2O (n=0, 2) were obtained and their crystal structure were solved. All families were extensively studied as proton conductors across a wide range of temperature and humidity conditions, displaying the Sn4+ derivatives the highest conductivity values of 7.99·10-4 and 6.63·10-3 S·cm-1 for Sn4+-BPMGLY and Sn4+-BPMGLY@700, respectively, at 95 °C and 95% relative humidity (RH) (Figure 1a). Furthermore, the cobalt phosphonates were utilized as precursors for non-precious metal catalysts (NPMCs), by pyrolysis in 5%-H2/Ar at different temperatures and studied as electrocatalysts towards the oxygen evolution reaction (OER), hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR)Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Healthcare workers hospitalized due to COVID-19 have no higher risk of death than general population. Data from the Spanish SEMI-COVID-19 Registry

Aim To determine whether healthcare workers (HCW) hospitalized in Spain due to COVID-19 have a worse prognosis than non-healthcare workers (NHCW). Methods Observational cohort study based on the SEMI-COVID-19 Registry, a nationwide registry that collects sociodemographic, clinical, laboratory, and treatment data on patients hospitalised with COVID-19 in Spain. Patients aged 20-65 years were selected. A multivariate logistic regression model was performed to identify factors associated with mortality. Results As of 22 May 2020, 4393 patients were included, of whom 419 (9.5%) were HCW. Median (interquartile range) age of HCW was 52 (15) years and 62.4% were women. Prevalence of comorbidities and severe radiological findings upon admission were less frequent in HCW. There were no difference in need of respiratory support and admission to intensive care unit, but occurrence of sepsis and in-hospital mortality was lower in HCW (1.7% vs. 3.9%; p = 0.024 and 0.7% vs. 4.8%; p<0.001 respectively). Age, male sex and comorbidity, were independently associated with higher in-hospital mortality and healthcare working with lower mortality (OR 0.211, 95%CI 0.067-0.667, p = 0.008). 30-days survival was higher in HCW (0.968 vs. 0.851 p<0.001). Conclusions Hospitalized COVID-19 HCW had fewer comorbidities and a better prognosis than NHCW. Our results suggest that professional exposure to COVID-19 in HCW does not carry more clinical severity nor mortality

Specificity and mutagenesis bias of the mycobacterial alternative mismatch repair analyzed by mutation accumulation studies

10 páginas, 3 figuras, 3 tablas. Material suplementario en: https://advances.sciencemag.org/content/suppl/2020/02/10/6.7.eaay4453.DC1The postreplicative mismatch repair (MMR) is an almost ubiquitous DNA repair essential for maintaining genome stability. It has been suggested that Mycobacteria have an alternative MMR in which NucS, an endonuclease with no structural homology to the canonical MMR proteins (MutS/MutL), is the key factor. Here, we analyze the spontaneous mutations accumulated in a neutral manner over thousands of generations by Mycobacterium smegmatis and its MMR-deficient derivative (ΔnucS). The base pair substitution rates per genome per generation are 0.004 and 0.165 for wild type and ΔnucS, respectively. By comparing the activity of different bacterial MMR pathways, we demonstrate that both MutS/L- and NucS-based systems display similar specificity and mutagenesis bias, revealing a functional evolutionary convergence. However, NucS is not able to repair indels in vivo. Our results provide an unparalleled view of how this mycobacterial system works in vivo to maintain genome stability and how it may affect Mycobacterium evolution.This work was supported by Plan Nacional de I + D + i 2013–2016 and the Instituto de Salud Carlos III, Subdireccion General de Redes y Centros de Investigacion Cooperativa, Ministerio de Economia, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0009)—cofinanced by the European Development Regional Fund “A Way to Achieve Europe”—by Operative Program Intelligent Growth 2014-2020 and grants FIS PI17/00159 from the Instituto de Salud Carlos III and SAF2015-72793-EXP from the Spanish Ministry of Science and Competitiveness (MINECO)-FEDER. E.C.-S. was the recipient of a PFIS predoctoral research fellowship (FI18/00036) cofinanced by the Instituto de Salud Carlos III and the European Social Fund. I.C., A.C.-O., and M.T.-P. are funded by projects of the 581 European Research Council (ERC) (638553-TB-ACCELERATE) and Ministerio de Economía y Competitividad research grant SAF2016-77346-R.Peer reviewe