COVID-19 pandemic has challenged public health systems worldwide, particularly affecting developing countries in Latin America like Ecuador. In this report, we exposed the fundamental role of the Ecuadorian universities to improve COVID-19 surveillance in the country, with an overall contribution over 15% of the total SARS-CoV-2 RT-PCR tests done. We highlight the role of our university during the first semester of the COVID-19 pandemic, contributing to a massive free SARS-CoV-2 testing up to almost 10% of the total diagnosis completed in the country, mainly focus on underserved urban, rural and indigenous communities. Finally, we described our contribution to a high quality and low-cost SARS-CoV-2 RT-PCR diagnostic in Ecuador.

Grey mould is reported in the vineyards of Castilla y León, Spain, every year. However, the natural populations of the pathogen have yet to be properly characterized. Vineyards from six wine‐producing areas were surveyed in 2002 and 2007, sampling from bunches of grapes with and without symptoms. A total of 283 Botrytis field isolates were selected for physiological and genetic analyses. Botrytis cinerea isolates predominated in the population, although isolates belonging to Botrytis pseudocinerea and Botrytis prunorum were also identified. These two species are recorded for the first time in Spain in this work. In addition, two isolates closely related to Botrytis californica were identified. Physiologically, the B. cinerea population is very diverse, displaying a normal distribution of aggressiveness values in Vitis vinifera leaves, suggesting a quantitative nature for this trait. Several isolates unable to cause infection were identified, most of them belonging to a mycelial morphotype. Population genetic analysis revealed that genotypic diversity is high and that multiple infections of the same bunch of grapes by different genotypes occur frequently. The high genotypic diversity observed, an even distribution of both mating types and the linkage disequilibrium values detected support a mixed mode of reproduction with low levels of clonality. The wine‐producing area in which each isolate was collected imposed a low degree of population differentiation, an effect that does not depend solely on the geographic distances but rather on the management practices used by growers and wine producer associations.

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Molecular mimicry is one of the evolutionary strategies that parasites use to manipulate the host metabolism and perform an effective infection. This phenomenon has been observed in several animal and plant pathosystems. Despite the relevance of this mechanism in pathogenesis, little is known about it in fungus-plant interactions. For that reason, we performed an in silico method to select plausible mimicry candidates for the Ustilago maydis-maize interaction. Our methodology uses a tripartite sequence comparison between the parasite, the host and non-parasitic organisms’ genomes. Furthermore, we use RNA-seq information to identify gene co-expression, and we determine subcellular localization to detect potential cases of co-localization in the imitator-imitated pairs. With these approximations, we found a putative extracellular formin in U. maydis with the potential to rearrange the host cell cytoskeleton. In parallel, we detect at least two maize genes involved in the cytoskeleton rearrangement differentially expressed under U. maydis infection; thus, this find increases the expectation for the potential mimicry role of the fungal protein. The use of several sources of data led us to develop a strict and replicable in silico methodology to detect molecular mimicry in pathosystems with enough information available. Furthermore, this is the first time that a genome-wide search has been performed to detect molecular mimicry in a U. maydis-maize system. Additionally, to allow the reproducibility of this experiment and the use of this pipeline, we create a Web server called Molecular mimicry finder, available in https://bioquimio.udla.edu.ec/molecular-mimicry/

Streptomyces clavuligerus is a Gram‐positive bacterium that is a high producer of secondary metabolites with industrial applications. The production of antibiotics such as clavulanic acid or cephamycin has been extensively studied in this species; nevertheless, other aspects, such as evolution or ecology, have received less attention. Furthermore, genes that arise from ancient events of lateral transfer have been demonstrated to be implicated in important functions of host species. This approximation discovered relevant genes that genomic analyses overlooked. Thus, we studied the impact of horizontal gene transfer in the S. clavuligerus genome. To perform this task, we applied whole‐genome analysis to identify a laterally transferred sequence from different domains. The most relevant result was a putative antimicrobial peptide (AMP) with a clear origin in the Hymenoptera order of insects. Next, we determined that two copies of these genes were present in the megaplasmid pSCL4 but absent in the S. clavuligerus ATCC 27064 chromosome. Additionally, we found that these sequences were exclusive to the ATCC 27064 strain (and so were not present in any other bacteria) and we also verified the expression of the genes using RNAseq data. Next, we used several AMP predictors to validate the original annotation extracted from Hymenoptera sequences and explored the possibility that these proteins had post‐translational modifications using peptidase cleavage prediction. We suggest that Hymenoptera AMP‐like proteins of S. clavuligerus ATCC 27064 may be useful for both species adaptation and as an antimicrobial molecule with industrial applications.

Expansins are a superfamily of proteins mainly present in plants that are also found in bacteria, fungi and amoebozoa. Expansin proteins bind the plant cells wall and relax the cellulose microfibrils without any enzymatic action. The evolution of this kind of proteins exposes a complex pattern of horizontal gene transferences that makes difficult to determine the precise origin of non-plant expansins. We performed a genome-wide search of inter-domain horizontal gene transfer events using Streptomyces species and found a plant-like expansin in the Streptomyces acidiscabies proteome. This finding leads us to study in deep the origin and the characteristics of this peculiar protein, also present in the species Kutzneria sp.744. Using phylogenetic analyses, we determine that indeed S. acidiscabies and Kutzneria sp.744 expansins are located inside the plants expansins A clade. Using secondary and tertiary structural information, we observed that the electrostatic potentials and the folding of expansins are similar, independently of the proteins’ origin. Using all this information, we conclude that S. acidiscabies and Kutzneria sp.744 expansins have a plant origin but differ from plant and bacterial canonical expansins. This finding suggests that the experimental research around this kind of expansins can be promissory in the future.

Nitric oxide regulates numerous physiological processes in species from all taxonomic groups. Here, its role in the early developmental stages of the fungal necrotroph Botrytis cinerea was investigated. Pharmacological analysis demonstrated that NO modulated germination, germ tube elongation and nuclear division rate. Experimental evidence indicates that exogenous NO exerts an immediate but transitory negative effect, slowing down germination-associated processes, and that this effect is largely dependent on the flavohemoglobin BCFHG1. The fungus exhibited a “biphasic response” to NO, being more sensitive to low and high concentrations than to intermediate levels of the NO donor. Global gene expression analysis in the wild-type and ΔBcfhg1 strains indicated a situation of strong nitrosative and oxidative stress determined by exogenous NO, which was much more intense in the mutant strain, that the cells tried to alleviate by upregulating several defense mechanisms, including the simultaneous upregulation of the genes encoding the flavohemoglobin BCFHG1, a nitronate monooxygenase (NMO) and a cyanide hydratase. Genetic evidence suggests the coordinated expression of Bcfhg1 and the NMO coding gene, both adjacent and divergently arranged, in response to NO. Nitrate assimilation genes were upregulated upon exposure to NO, and BCFHG1 appeared to be the main enzymatic system involved in the generation of the signal triggering their induction. Comparative expression analysis also showed the influence of NO on other cellular processes, such as mitochondrial respiration or primary and secondary metabolism, whose response could have been mediated by NmrA-like domain proteins.