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The Anthropocene era is characterized by a biodiversity crisis, where many species are pushing to extinction, causing alteration of the stability in the ecosystems and loss of their services. In this context, the translocation of endangered species is a powerful resource in conservation as long as its goals and appropriateness are clearly stated and it matches unambiguous criteria. Patella ferruginea is one of the most endangered marine species in the Mediterranean, and several translocations have been made with limited results in terms of survival. A methodology that mimics the natural topography of the substrate in the donor population based on Artificial Inert Mobile Substrates (AIMS, 40x20x10 cm) is proposed for restocking purposes. Three different treatments were tested: on substrate, slope, and cantilever depending on the position in which the AIMS were deployed. A total of 660 AIMS were installed within the donor area. The installation of such AIMS did not negatively affect either donor or receiving populations. A total of 188 specimens were translocated in three different attempts in 2018, 2019, and 2020, and no mortality was observed during the translocation process that lasted 24 h. Survival through the medium and long-term for the translocated specimens ranged from 80.6 to 91.5% after one month, 55.5 to 80.9% after eight months, and 48.4 to 76.6% after one year, with survival in the control population being 91.6% after four months and 87.5% after one year. Overall, recruits showed higher survival values than adults, whereas substrate treatment hosted more specimens (both recruits and adults) than slope and cantilever ones, while recruits were more abundant on cantilever treatment. The methodology has been proven to be useful for restocking and reintroduction purposes between donor and receiving areas.

The Mediterranean is one of the most biodiverse and anthropogenically impacted seas and the coralligenous is one of its most diverse habitats. Its presence is indicative of well-preserved areas and its associated species are considered among the best bioindicators for monitoring nearshore rocky habitats. This study aims to report the temporal fluctuations of the coralligenous community in the marine protected area of Jbel Moussa (Strait of Gibraltar) in a period concomitant with the rapid expansion of the non-indigenous species Rugulopteryx okamurae (E.Y.Dawson) I.K.Hwang, W.J.Lee & H.S.Kim in the area. From year 2015 to 2019, an area covering 36 m2 of the coralligenous habitat was monitored across three sites, including temperature logs from 2017 to 2019. After its first record in the area in 2017, R. okamurae became the most abundant species in only one year, followed by a change in the coralligenous community structure and a regression of the bioindicator species Paramuricea clavata (Risso, 1826) and Mesophyllum expansum (Philippi) Cabioch & M.L.Mendoza. These species are sensitive to increases in water temperature and were already under a gradual regression due to anthropogenic disturbances and previous biological invasions, all of which could have reduced niche competition in the area and favoured the impacts caused by R. okamurae in the area. Results highlight the need of a rapid administrative response to increase mitigation efforts on this protected habitat. Due the potential expansion of this non-indigenous invasive species to the Mediterranean Sea, the present study could provide valuable information for future monitoring, conservation and management actions.

Cyclobutane pyrimidine dimer (CPD) photolyases harness the energy of blue light to repair UV-induced DNA CPDs. Upon binding, CPD photolyases cause the photodamage to flip out of the duplex DNA and into the catalytic site of the enzyme. This process, called base-flipping, induces a kink in the DNA, as well as an unpaired bubble, which are stabilized by a network of protein–nucleic acid interactions. Previously, several co-crystal structures have been reported in which the binding mode of CPD photolyases has been studied in detail. However, in all cases the internucleoside linkage of the photodamage site was a chemically synthesized formacetal analogue and not the natural phosphodiester. Here, the first crystal structure and conformational analysis via molecular-dynamics simulations of a class II CPD photolyase in complex with photodamaged DNA that contains a natural cyclobutane pyrimidine dimer with an intra-lesion phosphodiester linkage are presented. It is concluded that a highly conserved bubble-intruding region (BIR) mediates stabilization of the open form of CPD DNA when complexed with class II CPD photolyases.

Cell–cell and cell-substrate based adhesion of yeasts are major determinants of their adoption of different life styles. Genome-mining of ascomycetous GPI-anchored cell wall proteins with lectin-like PA14 domains identified a unique class of putative adhesins in the clade of methylotrophic Komagataella yeasts, many of which are known to colonize plants and insects involving yet unknown adhesion mechanisms. Here, we report the functional and structural analysis of two of its members: KpFlo1 (=Cea1), that is highly specific for terminal N-acetylglucosamine moieties, and KpFlo2, which represents an orphan lectin with intact binding site but unknown specificity. Crystal structures of the Cea1 adhesion domain complexed to N-acetylglucosamine and N,N′-diacetylchitobiose reveal a Ca2+-dependent binding mode that differs from other members of the PA14/Flo5 adhesin family. Heterologous expression of Cea1A in Saccharomyces cerevisiae promotes cellular adhesion to non-reducing ends of non-crystalline chitin. Overall, our data suggest that high-affinity recognition of β-GlcNAc-capped glycans by Cea1 enable Komagataella species to interact with surface cues present in fungi and insects.

Laccases are multi-copper oxidases that catalyze the oxidation of various organic and inorganic compounds by reducing O2 to water. Here we report the crystal structure at 1.8 Å resolution of a native laccase (designated nLcc4) isolated from a white-rot fungus Lentinus sp. nLcc4 is composed of three cupredoxin-like domains D1-D3 each folded into a Greek key β-barrel topology. T1 and T2/T3 copper binding sites and three N-glycosylated sites at Asn75, Asn238, and Asn458 were elucidated. Initial rate kinetic analysis revealed that the kcat, Km, and kcat/Km of nLcc4 with substrate ABTS were 3,382 s-1, 65.0 ± 6.5 μM, and 52 s-1μM-1, respectively; and the values with lignosulfonic acid determined using isothermal titration calorimetry were 0.234 s-1, 56.7 ± 3.2 μM, and 0.004 s-1μM-1, respectively. Endo H-deglycosylated nLcc4 (dLcc4), with only one GlcNAc residue remaining at each of the three N-glycosylation sites in the enzyme, exhibited similar kinetic efficiency and thermal stability to that of nLcc4. The isolated Lcc4 gene contains an open reading frame of 1563 bp with a deduced polypeptide of 521 amino acid residues including a predicted signaling peptide of 21 residues at the N-terminus. Recombinant wild-type Lcc4 and mutant enzymes N75D, N238D and N458D were expressed in Pichia pastoris cells to evaluate the effect on enzyme activity by single glycosylation site deficiency. The mutant enzymes secreted in the cultural media of P. pastoris cells were observed to maintain only 4-50% of the activity of the wild-type laccase. Molecular dynamics simulations analyses of various states of (de-)glycosylation in nLcc support the kinetic results and suggest that the local H-bond networks between the domain connecting loop D2-D3 and the glycan moieties play a crucial role in the laccase activity. This study provides new insights into the role of glycosylation in the structure and function of a Basidiomycete fungal laccase.

We study norm attaining properties of the Arens extensions of multilinear forms defined on Banach spaces. Among other related results, we construct a multilinear form on ℓ1 with the property that only some fixed Arens extensions determined a priori attain their norms. We also study when multilinear forms can be approximated by ones with the property that only some of their Arens extensions attain their norms.

The multi S1/P1 nuclease AtBFN2 (EC 3.1.30.1) encoded by the Arabidopsis thaliana At1g68290 gene is a glycoprotein that digests RNA, ssDNA, and dsDNA. AtBFN2 depends on three zinc ions for cleaving DNA and RNA at 3'-OH to yield 5'-nucleotides. In addition, AtBFN2's enzymatic activity is strongly glycan dependent. Plant Zn(2+)-dependent endonucleases present a unique fold, and belong to the Phospholipase C (PLC)/P1 nuclease superfamily. In this work, we present the first complete, ligand-free, AtBFN2 crystal structure, along with sulfate, phosphate and ssDNA co-crystal structures. With these, we were able to provide better insight into the glycan structure and possible enzymatic mechanism. In comparison with other nucleases, the AtBFN2/ligand-free and AtBFN2/PO4 models suggest a similar, previously proposed, catalytic mechanism. Our data also confirm that the phosphate and vanadate can inhibit the enzyme activity by occupying the active site. More importantly, the AtBFN2/A5T structure reveals a novel and conserved secondary binding site, which seems to be important for plant Zn(2+)-dependent endonucleases. Based on these findings, we propose a rational ssDNA binding model, in which the ssDNA wraps itself around the protein and the attached surface glycan, in turn, reinforces the binding complex.

For two complex Banach spaces X and Y, in this paper, we study the generalized spectrum ℳb(X,Y) of all nonzero algebra homomorphisms from ℋb(X), the algebra of all bounded type entire functions on X, into ℋb(Y). We endow ℳb(X,Y) with a structure of Riemann domain over ℒ(X*,Y*) whenever X is symmetrically regular. The size of the fibers is also studied. Following the philosophy of (Aron et al., 1991), this is a step to study the set ℳb,∞(X,BY) of all nonzero algebra homomorphisms from ℋb(X) into ℋ∞(BY) of bounded holomorphic functions on the open unit ball of Y and ℳ∞(BX,BY) of all nonzero algebra homomorphisms from ℋ∞(BX) into ℋ∞(BY).

V. cholerae can form sessile biofilms associated with abiotic surfaces, cyanobacteria, zoo-plankton, mollusks, or crustaceans. Along with the vibrio polysaccharide, secreted proteins of the rbm gene cluster are key to the biofilm ultrastructure. Here we provide a thorough structural characterization of RbmA, a protein involved in mediating cell-cell and cell-biofilm contacts. We correlate our structural findings with initial ligand specificity screening results, NMR protein-ligand interaction analysis, and complement our results with a full biocomputational study.

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Abstract  Let H be a (real or complex) Hilbert space. Using spectral theory and properties of the Schatten–Von Neumann operators, we prove that every symmetric tensor of unit norm in $${H \hat{\otimes} _{s,\pi _{s}}H}$$ is an infinite absolute convex combination of points of the form $${x\otimes x}$$ with x in the unit sphere of the Hilbert space. We use this to obtain explicit characterizations of the smooth points of the unit ball of $${H \hat{\otimes} _{s,\pi _{s}}H}$$ . [ABSTRACT FROM AUTHOR]

Abstract  Bohr showed that the width of the strip (in the complex plane) on which a given Dirichlet series $${\sum a_n/ n^s, \, s \in \mathbb{C}}$$, converges uniformly but not absolutely, is at most 1/2, and Bohnenblust-Hille that this bound in general is optimal. We prove that for a given infinite dimensional Banach space Y the width of Bohr’s strip for a Dirichlet series with coefficients a n in Y is bounded by 1 - 1/Cot (Y), where Cot (Y) denotes the optimal cotype of Y. This estimate even turns out to be optimal, and hence leads to a new characterization of cotype in terms of vector valued Dirichlet series. [ABSTRACT FROM AUTHOR]

Millennials o Generación Y es la generación de perso- nas nacidas entre los años 1982 y 2002 y que subsigue a la Generación X (personas nacidas entre 1960 y 1981). En el deporte, y específicamente en el ciclismo, los Mi- llennials promocionan la filosofía 2.0. Una filosofía que caracteriza al ciclista 2.0 como un atleta que respeta por convicción el Código Mundial de Dopaje. En este estu- dio han participado 34 ciclistas españoles federados, correspondientes a la Generación Y, (16 varones y 18 féminas; 19 ± 6,55 años). Mediante un diseño de trabajo cualitativo, utilizando como instrumento metodológico la entrevista, se ofrece un análisis descriptivo de 8 cate- gorías sobre las características del ciclista español 2.0. Diferentes marcos sociológicos han permitido codificar y filtrar las transcripciones. Para realizar una profundiza- ción del tema, se utilizaron los programas Word y Excel 2007 y el programa estadístico QSR NVivo 10 para Win- dows. El análisis descriptivo de las 8 categorías muestra un ciclista 2.0 predispuesto a un ciclismo limpio. A pesar de esta aseveración, se sigue detectando un importan- te desequilibrio entre las medidas disuasorias aplicadas ante el dopaje. Este desequilibrio, ya detectado en las generaciones precedentes a la Generación Y, hace que el problema del dopaje y sus escándalos sean temas de actualidad sin encontrarse aún una solución definitiva.