The benzoyl-CoA pathway serves as a genomic marker to identify the oxygen requirements in the degradation of aromatic hydrocarbons.

The first step of anaerobic benzoate degradation is the formation of benzoyl-coenzyme A by benzoate-coenzyme A ligase (BCL). The anaerobic route is steered by benzoyl-CoA reductase, which promotes benzoyl-CoA breakdown, which is subsequently oxidized. In certain bacteria at low oxygen conditions, the aerobic metabolism of monoaromatic hydrocarbons occurs through the degradation Box pathway. These pathways have undergone experimental scrutiny in Alphaproteobacteria and Betaproteobacteria and have also been explored bioinformatically in representative Betaproteobacteria. However, there is a gap in our knowledge regarding the distribution of the benzoyl-CoA pathway and the evolutionary forces propelling its adaptation beyond that of representative bacteria. To address these questions, we used bioinformatic procedures to identify the BCLs and the lower pathways that transform benzoyl-CoA. These procedures included the identification of conserved motifs. As a result, we identified two motifs exclusive to BCLs, describing some of the catalytic properties of this enzyme. These motifs helped to discern BCLs from other aryl-CoA ligases effectively. The predicted BCLs and the enzymes of lower pathways were used as genomic markers for identifying aerobic, anaerobic, or hybrid catabolism, which we found widely distributed in Betaproteobacteria. Despite these enhancements, our approach failed to distinguish orthologs from a small cluster of paralogs exhibiting all the specified features to predict an ortholog. Nonetheless, the conducted phylogenetic analysis and the properties identified in the genomic context aided in formulating hypotheses about how this redundancy contributes to refining the catabolic strategy employed by these bacteria to degrade the substrates.

Dominance of Three Sublineages of the SARS-CoV-2 Delta Variant in Mexico.

In this study, we analyzed the sequences of SARS-CoV-2 isolates of the Delta variant in Mexico, which has completely replaced other previously circulating variants in the country due to its transmission advantage. Among all the Delta sublineages that were detected, 81.5 % were classified as AY.20, AY.26, and AY.100. According to publicly available data, these only reached a world prevalence of less than 1%, suggesting a possible Mexican origin. The signature mutations of these sublineages are described herein, and phylogenetic analyses and haplotype networks are used to track their spread across the country. Other frequently detected sublineages include AY.3, AY.62, AY.103, and AY.113. Over time, the main sublineages showed different geographical distributions, with AY.20 predominant in Central Mexico, AY.26 in the North, and AY.100 in the Northwest and South/Southeast. This work describes the circulation, from May to November 2021, of the primary sublineages of the Delta variant associated with the third wave of the COVID-19 pandemic in Mexico and highlights the importance of SARS-CoV-2 genomic surveillance for the timely identification of emerging variants that may impact public health.

Prevalencia de brucelosis bovina, equina y humana en Caldas-Colombia-Sur America / Prevalence of bovine, equine and human brucellosis in Caldas-Colombia- South America

La brucelosis es considerada como una de las enfermedades infecciosas más importantes enColombia y el mundo por sus implicaciones en la salud pública, y sus repercusiones productivas en el ámbito pecuario, dejando grandes pérdidas a la economía nacional. Considerando que existe poca información sobre su prevalencia en el ámbito regional, en el transcurso de los años 2001-2002 se realizó un estudio sobre la prevalencia de la brucelosis bovina, equina y humana (personal con alto riesgo de infección) en el departamento de Caldas. Para el desarrollo del trabajo se utilizaron como pruebas diagnósticas, las técnicas rosa de Bengala y ELISA Indirecta; además se realizaron pruebas confirmatorias como ELISA competitiva y fijación de complemento para los equinos. Los resultados obtenidos en 2.434 muestras de bovinos mostraron una baja incidencia para brucelosis (0,6%), que correspondió a 15 animales hembras, distribuida en las cuatro zonas del departamento de la siguiente manera: oriente 0,24% (6 bovinos: 3 de La Dorada y 3 de la Victoria); centro-sur 0,16% (4 bovinos: 2 de Manizales, 1 de Belacázar y 1 de Villamaría); norte 0,12% (3 bovinos: 1 de Neira, 1 de Aranzazu y 1 de Salamina) y occidente 0,08% (2 bovinos, ambos en Risaralda), encontrándose animales positivos en rangos de edad de 18 a 90 meses. No se hallaron equinos reactores positivos utilizando las pruebas confirmatorias. Los resultados obtenidos en 676 muestras de humanos, arrojaron una baja prevalencia (0,14%), correspondiente a un matarife, con síntomas compatibles para brucelosis. La técnica rosa de Bengala aumentó la sensibilidad al agregar el doble de la cantidad de suero con respecto al antígeno Rosa de Bengala.

Brucellosis is considered one of the most important infectious diseases in Colombia and the world due to its implications in public health, and its productive consequences in the livestock field that is producing big losses in the economy of the country. Since there is limited information on Brucellosis in Caldas, in 2001-2002 a prevalence study on bovine, equine and human (high risk personnel) Brucellosis was carried out in the department of Caldas. For the development of the research the following diagnostic tests were used: Bengal Rose Test, indirect ELISA, as well as confirmatory tests, such as competitive ELISA and Complement Fixation, for the horses. The results obtained in 2,434 bovine samples shown a low incidence of Brucellosis (0.6%), corresponding to 15 females, distributed in the four zones of the department as follows: east zone with 0.24% (3 in La Dorada and 3 in La Victoria); central-south zone with 0.16% (2 in Manizales, 1 in Belalcazar and 1 in Villamaría); north zone with 0.12% (1 in Neira, 1 in Aranzazu and 1 in Salamina); and west zone with 0.08% (2 in Risaralda). The animals that tested positive were between 18 to 90 months of age. No equine reactors tested positive with the confirmatory test. The results obtained in 676 human samples showed a low prevalence (0.14%), corresponding to a slaugtherman with symptoms associated with Brucellosis. The Bengal Rose Test increased the sensibility when adding twice as much serum, regarding the Bengal Rose antigen.