Bacterial resistance is responsible for a wide variety of health problems, both in children and adults. The persistence of symptoms and infections are mainly treated with β-lactam antibiotics. The increasing resistance to those antibiotics by bacterial pathogens generated the emergence of extended-spectrum β-lactamases (ESBLs), an actual public health problem. This is due to rapid mutations of bacteria when exposed to antibiotics. In this case, β-lactamases are enzymes used by bacteria to hydrolyze the beta-lactam rings present in the antibiotics. Therefore, it was necessary to explore novel molecules as potential β-lactamases inhibitors to find antibacterial compounds against infection caused by ESBLs. A computational methodology based on molecular docking and molecular dynamic simulations was used to find new microalgae metabolites inhibitors of β-lactamase. Six 3D β-lactamase proteins were selected, and the molecular docking revealed that the metabolites belonging to the same structural families, such as phenylacridine (4-Ph), quercetin (Qn), and cryptophycin (Cryp), exhibit a better binding score and binding energy than commercial clinical medicine β-lactamase inhibitors, such as clavulanic acid, sulbactam, and tazobactam. These results indicate that 4-Ph, Qn, and Cryp molecules, homologous from microalgae metabolites, could be used, likely as novel β-lactamase inhibitors or as structural templates for new in-silico pharmaceutical designs, with the possibility of combatting β-lactam resistance

New ß-glucosidases with product (glucose) or ethanol tolerances are greatly desired to make industrial processes more marketable and efficient. Therefore, this report describes the in silico/vitro characterization of Bg10, a metagenomically derived homodimeric ß-glucosidase that exhibited a V_max of 10.81 ± 0.43 μM min^-1, K_cat of 175.1± 6.91 min^-1, and K_m of 0.49 ± 0.12 mM at a neutral pH and 37°C when pNP-ß-D-glucopyranoside was used as the substrate, and the enzyme retained greater than 80% activity within the respective pH and temperature ranges of 6.5 to 8.0 and 35 to 40°C. The enzyme was stimulated by its product, glucose; consequently, the Bg10 activity against 50 and 100 mM of glucose were increased by 36.8% and 22%, respectively, while half of the activity was retained at 350 mM. Moreover, the Bg10 was able to hydrolyse 55% (milk sample) and 100% (purified sugar) of the lactose at low (6°C) and optimum (37°C) temperatures, respectively, suggesting the possibility of further optimization of the reaction for lactose-free dairy production. In addition, the enzyme was able to fully hydrolyse 40 mM of cellobiose at one hour and was tolerant to ethanol up to concentrations of 500 mM (86% of activity), while a 1 M concentration still resulted in 41% residual activity, which could be interesting for biofuel production.

En la Sierra Nevada de Santa Marta los cultivos de cacao están conformados mayoritariamente por cultivares híbridos comerciales y, aunque se encuentran cacaos nativos, estos son poco cultivados. Dada la necesidad de verificar si estos cultivares de cacao encontrados en la Sierra pertenecen al grupo genético tipo Criollo, se realizó una caracterización fenotípica y genotípica de cacaos del municipio Dibulla, La Guajira. Para esto, se muestrearon 11 cultivares en Mingueo. Los rasgos fenotípicos se evaluaron empleando descriptores UPOV para cacao. Los parámetros cualitativos y cuantitativos se cotejaron por análisis de conglomerado y análisis de componentes principales (ACP), y las variables cuantitativas se compararon a través de la prueba no paramétrica test de Mann-Whitney. Para evaluar las relaciones genéticas, se estandarizaron protocolos de biología molecular y se secuenció la región ITS. A partir de las secuencias, se realizaron agrupamientos por métodos de distancia y filogenéticos. Finalmente, se encontraron diferencias significativas entre las semillas (p = 0,01), y resalta la coloración blanca del cotiledón de los criollos en contraste con la coloración púrpura oscura de los híbridos. Asimismo, los análisis de conglomerados, ACP y los análisis de secuencias demostraron diferencias entre el grupo de los cacaos nativos y los híbridos comerciales cultivados; además, los cacaos nativos se emparentan con el grupo de cacao tipo Criollo.

For several centuries, microorganisms and enzymes have been used for many different applications. Although many enzymes with industrial applications have already been reported, different screening technologies, methods and approaches are constantly being developed in order to allow the identification of enzymes with even more interesting applications. In our work, we have performed data mining on the Chitinophaga sp. genome, a gram-negative bacterium isolated from a bacterial consortium of sugarcane bagasse isolated from an ethanol plant. The analysis of 8 Mb allowed the identification of the chtcp gene, previously annotated as putative Cht4039. The corresponding codified enzyme, denominated as ChtCP, showed the HEXXH conserved motif of family M32 from thermostable carboxypeptidases. After expression in E. coli, the recombinant enzyme was characterized biochemically. ChtCP showed the highest activity versus benziloxicarbonil Ala-Trp at pH 7.5, suggesting a preference for hydrophobic substrates. Surprisingly, the highest activity of ChtCP observed was between 55 °C and 75 °C, and 62% activity was still displayed at 100 °C. We observed that Ca²⁺, Ba²⁺, Mn²⁺ and Mg²⁺ ions had a positive effect on the activity of ChtCP, and an increase of 30 °C in the melting temperature was observed in the presence of Co²⁺. These features together with the structure of ChtCP at 1.2 Å highlight the relevance of ChtCP for further biotechnological applications.

Colombia is the country with the sixth highest amount of water reserves in the world, and 25% of its territory is covered by wetlands. However, approximately 50% of the country’s water is estimated to exhibit some type of contamination related to anthropic activities. An alternative for the treatment and the recovery of its bodies of water is the use of microalgae, unicellular, and mixotrophic microorganisms, as these bioreactors are highly adaptable to the environment, and their maintenance costs are minimal, because they feed on almost any substrate. In fact, different countries have already reported using microalgae as bioremediators for bodies of water. The use of these microphytes is efficient because they metabolize, degrade, or bioaccumulate heavy metals, pesticides, emerging pollutants, and antibiotics. In general, strategies relying on microalgae to eliminate pollutants are very similar to one another. For example, the first stage often includes a process of bioadsorption, consumption, degradation, and accumulation, wherein the microalgae use molecules generated from their own cellular metabolism. Some pilot studies focusing on the phycoremediation of marshes and other bodies of water have already been conducted in Colombia; however, more studies on process optimization, effectively leveraging the biodiversity of the existing microalgae, and better adapting microalgae to the region are still required.