Microbiologically induced carbonate precipitation (MICP) is a well-known biogeochemical process that allows the formation of calcium carbonate deposits in the extracellular environment. The high concentration of carbonate and calcium ions on the bacterial surface, which serves as nucleation sites, promotes the calcium carbonate precipitation filling and binding deteriorated materials. Historic buildings and artwork, especially those present in open sites, are susceptible to enhanced weathering resulting from environmental agents, interaction with physical-chemical pollutants, and living organisms, among others. In this work, some published variations of a novel and ecological surface treatment of heritage structures based on MICP are presented and compared. This method has shown to be successful as a restoration, consolidation, and conservation tool for improvement of mechanical properties and prevention of unwanted gas and fluid migration from historical materials. The treatment has revealed best results on porous media matrixes; nevertheless, it can also be applied on soil, marble, concrete, clay, rocks, and limestone. MICP is proposed as a potentially safe and powerful procedure for efficient conservation of worldwide heritage structures.

Peptide therapeutics play a key role in the development of new medical treatments. The traditional focus on endogenous peptides has shifted from first discovering other natural sources of these molecules, to later synthesizing those with unique bioactivities. This review provides concise information concerning antimicrobial peptides derived from marine crustaceans for the development of new therapeutics. Marine arthropods do not have an adaptive immune system, and therefore, they depend on the innate immune system to eliminate pathogens. In this context, antimicrobial peptides (AMPs) with unique characteristics are a pivotal part of the defense systems of these organisms. This review covers topics such as the diversity and distribution of peptides in marine arthropods (crustacea and chelicerata), with a focus on penaeid shrimps. The following aspects are covered: the defense system; classes of AMPs; molecular characteristics of AMPs; AMP synthesis; the role of penaeidins, anti-lipopolysaccharide factors, crustins, and stylicins against microorganisms; and the use of AMPs as therapeutic drugs. This review seeks to provide a useful compilation of the most recent information regarding AMPs from marine crustaceans, and describes the future potential applications of these molecules.

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Atmospheric nitrogen fixation carried out by microorganisms has environmental and industrial importance, related to the increase of soil fertility and productivity. The present work proposes the development of a new high precision system that allows the recognition of amino acid sequences of the nitrogenase enzyme (NifH) as a promising way to improve the identification of diazotrophic bacteria. For this purpose, a database obtained from UniProt built a processed dataset formed by a set of 4911 and 4782 amino acid sequences of the NifH and non-NifH proteins respectively. Subsequently, the feature extraction was developed using two methodologies: (i) k-mers counting and (ii) embedding layers to obtain numerical vectors of the amino acid chains. Afterward, for the embedding layer, the data was crossed by an external trainable convolutional layer, which received a uniform matrix and applied convolution using filters to obtain the feature maps of the model. Finally, a deep neural network was used as the primary model to classify the amino acid sequences as NifH protein or not. Performance evaluation experiments were carried out, and the results revealed an accuracy of 96.4%, a sensitivity of 95.2%, and a specificity of 96.7%. Therefore, an amino acid sequence-based feature extraction method that uses a neural network to detect N-fixing organisms is proposed and implemented. NIFtHool is available from: https://nifthool.anvil.app/

We evaluated the compatibility between two nitrogen-fixing Bradyrhizobium inoculant strains and phosphate-solubilizing fungal strains and the effect of co-inoculation of these bacterial and fungal strains on cowpea growth under different N and P conditions.First, the compatibility between Bradyrhizobium strains UFLA03-84 and INPA03-11B and fungi Haematonectria ipomoeae FSA381, Eleutherascus lectardii FSA257a, Pochonia chlamydosporia var. catenulata FSA109, and Acremonium polychromum FSA115 was tested in both solid and liquid media. Cowpea growth and nodulation promotion under two mineral N doses and two P conditions (a low dose of soluble P plus a high dose of Ca 3 (PO 4 ) 2 and another condition with a high dose of soluble P) were tested with two N 2 fixing Bradyrhizobium strains co-inoculated with each of the P-solubilizing fungal strains FSA109, FSA115, and FSA381. There was compatibility between each fungal strain and the two Bradyrhizobium strains, except for FSA257a with either of the bacterial strains in liquid medium. When both mineral N and P were limiting, plants were able to grow and accumulate N and P based on biological N 2 fixation and solubilization of calcium phosphate in the same amount as the mineral N and soluble phosphate. Even when both nutrients were fully available, the type of co-inoculation promoted plant growth and nutrient accumulation.The responses varied in accordance with the co-inoculated strains, the N source, and the P source, reflecting the enormous complexity of the biological interactions between plants and microorganisms, and the nutrient conditions provided by the environment.

El objetivo del presente trabajo fue evaluar la actividad bactericida del agua de plata coloidal sobre los microorganismos indicadores de la calidad microbiológica aislados a partir de muestras de: (i) agua de 16 canales de riego en la provincia de Tungurahua-Ecuador y (ii) los utensilios e insumos de una cocina en una cafetería en Quito-Ecuador. Para esto se confrontó 4 ppm, 10 pmm y 15 ppm de agua de plata coloidal durante 15, 30 y 60 minutos con los crecimientos equivalentes a A625 de 0,08-0,1 de las cepas de: Escherichia coli ATCC 11229, Salmonella Choleraesuis ATCC 10708, Staphylococcus aureus ATCC 6538 y Pseudomonas aeruginosa ATCC 15442. Una vez estandarizada la técnica se comparó la densidad poblacional de: mesófilos aerobios, E. coli -coliformes totales y enterobacterias de 16 muestras de agua de canales de riego y de 11 superficies de preparación de alimentos antes y después de la exposición a 4 ppm, 10 ppm y 15 ppm de la suspensión de plata coloidal. La plata inhibió el crecimiento de todos los grupos microbianos evaluados en los canales de riego excepto en el 31,3% (n=5) de los casos en los que a 4 ppm de plata los recuentos de las bacterias mesófilas aerobias estuvieron en un rango de entre 10x102 UFC/mL y 40x102 UFC/mL. Para el caso de las muestras recolectadas en la cafetería, los recuentos de mesófilos aerobios disminuyeron en el 64,3% (n=9) del total de superficies muestreadas mientras que el número de E. coli - coliformes totales disminuyó en el 93% (n=13) de las áreas muestreadas a partir los 5 minutos de exposición con de 4 ppm de agua de plata coloidal.

La ateroesclerosis y sus complicaciones constituyen una de las mayores causas de morbi-mortalidad a nivel mundial. Sin embargo, solo la mitad de los casos se justifica por los factores de riesgo tradicionales. No obstante, desde hace casi cinco décadas se ha intentado encontrar causas no tradicionales asociadas a la enfermedad ateroesclerótica. Varios agentes infecciosos han emergido como posibles candidatos centralizándose la investigación en Chlamydophila pneumoniae por su capacidad de infectar las células endoteliales durante el proceso ateroesclerótico. A lo largo del tiempo, múltiples estudios han tratado de probar la causalidad de C. pneumoniae en el proceso ateroesclerótico y sus complicaciones. A pesar de esto, hasta la fecha las conclusiones son ambiguas y de poca relevancia para la práctica clínica diaria.Palabras clave: Aterosclerosis; Chlamydophila pneumoniae; Enfermedades Cardiovasculares (fuente: DeCS) ABSTRACTAtherosclerosis and its complications are a major cause of morbidity and mortality worldwide. However, only half of the cases are justified by traditional risk factors. Nevertheless for almost five decades ago, has tried to find non-traditional causes associated with atherosclerotic disease. Various infectious agents have emerged as potential candidates being centralized research Chlamydophila pneumoniae by its ability to infect endothelial cells in the atherosclerotic process. Over time many studies have tried to prove the causality of C. pneumoniae in the atherosclerotic process and its complications. Despite this, to date the findings are ambiguous and of little relevance to daily clinical practice.

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