A new subterranean species of Entomoculia Croissandeau, 1891 from the Canary Islands, Spain (Coleoptera, Staphylinidae, Leptotyphlinae)

The genus Entomoculia Croissandeau, 1891, is the only representative of the subfamily Leptotyphlinae present in the Canary Islands and is composed by only two species: E. (Stenotyphlus) canariensis Outerelo, 1982, from La Gomera and E. (Stenotyphlus) lauricola Outerelo & Hernández, 1989, from Tenerife, both found in deep soil (= endogean) habitats. In this paper, we describe Entomoculia (Stenotyphlus) vulcanica sp. nov., the third Canarian species of the genus, which is reported for the first time from Gran Canaria and has been found in the mesovoid shallow substratum “MSS”. This new species has some of the characteristics that are specific to Canarian species of the genus Entomoculia, such as the lack of a denticle or spiniform process on the male metatrochanters. However, it is a remarkable species as it is the only known species of the genus with a tridentate labrum, as the labrum is monodentate in the species so far known from Canary Islands and bidentate in non-Canary species. We provide a key to Canarian species and illustrations of the habitus and the primary and secondary sexual characters of the male. We also describe the sampling techniques used and provide detailed information on habitat characteristics and associated arthropod fauna.

Hernando, Carles; López, Heriberto.

Contributions to Entomology, 74(1): 1-6 (2024)
DOIDigital.CSIC

Towards a Canary Islands barcode database for soil biodiversity: revealing cryptic and unrecorded mite species diversity within insular soils

Soil arthropod diversity contributes to a high proportion of the total biodiversity on Earth. However, most soil arthropods are still undescribed, hindering our understanding of soil functioning and global biodiversity estimations. Inventorying soil arthropods using conventional taxonomical approaches is particularly difficult and costly due to the great species richness, abundance and local-scale heterogeneity of mesofauna communities and the poor taxonomic background knowledge of most lineages. To alleviate this situation, we have designed and implemented a molecular barcoding framework adapted to soil fauna. This pipeline includes different steps, starting with a morphology-based selection of specimens which are imaged. Then, DNA is extracted non-destructively. Both images and voucher specimens are used to assign a taxonomic identification, based on morphology that is further checked for consistency with molecular information. Using this procedure, we studied 239 specimens of mites from the Canary Islands including representatives of Mesostigmata, Sarcoptiformes and Trombidiformes, of which we recovered barcode sequences for 168 specimens that were morphologically identified to 49 species, with nine specimens that could only be identified at the genus or family levels. Multiple species delimitation analyses were run to compare molecular delimitations with morphological identifications, including ASAP, mlPTP, BINs and 3% and 8% genetic distance thresholds. Additionally, a species-level search was carried out at the Biodiversity Databank of the Canary Islands (BIOTA) to evaluate the number of species in our dataset that were not previously recorded in the archipelago. In parallel, a sequence-level search of our sequences was performed against BOLD Systems. Our results reveal that multiple morphologically identified species correspond to different molecular lineages, which points to significant levels of unknown cryptic diversity within the archipelago. In addition, we evidenced that multiple species in our dataset constituted new records for the Canary Islands fauna and that the information for these lineages within online genetic repositories is very incomplete. Our study represents the first systematic effort to catalogue the soil arthropod mesofauna of the Canary Islands and establishes the basis for the Canary Islands Soil Biodiversity barcode database. This resource will constitute a step forward in the knowledge of these arthropods in a region of special interest.

Santos-Perdomo, Irene; Suárez, Daniel; Moraza, María L.; Arribas, Paula; Andújar, Carmelo.

Biodiversity Data Journal, 12, e113301: 1-31 (2024)
DOIDigital.CSIC

Chemical Insights into Oxidative and Nitrative Modifications of DNA

This review focuses on DNA damage caused by a variety of oxidizing, alkylating, and nitrating species, and it may play an important role in the pathophysiology of inflammation, cancer, and degenerative diseases. Infection and chronic inflammation have been recognized as important factors in carcinogenesis. Under inflammatory conditions, reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from inflammatory and epithelial cells, and result in the formation of oxidative and nitrative DNA lesions, such as 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and 8-nitroguanine. Cellular DNA is continuously exposed to a very high level of genotoxic stress caused by physical, chemical, and biological agents, with an estimated 10,000 modifications occurring every hour in the genetic material of each of our cells. This review highlights recent developments in the chemical biology and toxicology of 2′-deoxyribose oxidation products in DNA.

Curieses Andrés, Celia María; Lastra, José M. P. de la; Juan, Celia Andrés; Plou Gasca, Francisco José; Pérez-Lebeña, Eduardo.

International Journal of Molecular Sciences 24(20), 15240: 1-43 (2023)
DOIDigital.CSIC

Illuminating a Solvent-Dependent Hierarchy for Aromatic CH/π Complexes with Dynamic Covalent Glyco-Balances

CH/π interactions are prevalent among aromatic complexes and represent invaluable tools for stabilizing well-defined molecular architectures. Their energy contributions are exceptionally sensitive to various structural and environmental factors, resulting in a context-dependent nature that has led to conflicting findings in the scientific literature. Consequently, a universally accepted hierarchy for aromatic CH/π interactions has remained elusive. Herein, we present a comprehensive experimental investigation of aromatic CH/π complexes, employing a novel approach that involves isotopically labeled glyco-balances generated in situ. This innovative strategy not only allows us to uncover thermodynamic insights but also delves into the often less-accessible domain of kinetic information. Our analyses have yielded more than 180 new free energy values while considering key factors such as solvent properties, the interaction geometry, and the presence and nature of accompanying counterions. Remarkably, the obtained results challenge conventional wisdom regarding the stability order of common aromatic complexes. While it was believed that cationic CH/π interactions held the highest strength, followed by polarized CH/π, nonpolarized CH/π, and finally anionic CH/π interactions, our study reveals that this hierarchy can be subverted depending on the environment. Indeed, the performance of polarized CH/π interactions can match or even outcompete that of cationic CH/π interactions making them a more reliable stabilization strategy across the entire spectrum of solvent polarity. Overall, our results provide valuable guidelines for the selection of optimal interacting partners in every chemical environment, allowing the design of tailored aromatic complexes with applications in supramolecular chemistry, organocatalysis, and/or material sciences.

Díaz-Casado, Laura; Villacampa, Alejandro; Corzana, Francisco; Jiménez-Barbero, Jesús; Gómez, Ana M.; Santana, Andrés G.; Asensio, Juan Luis.

JACS: 1-15 (2024)
DOIDigital.CSIC