Cazando el genoma de un cazador: la genómica al rescate del lince ibérico

Peer reviewe

Joint effects of population size and isolation on genetic erosion in fragmented populations: finding fragmentation thresholds for management

Size and isolation of local populations are main parameters of interest when assessing the genetic consequences of habitat fragmentation. However, their relative influence on the genetic erosion of local populations remains unclear. In this study, we first analysed how size and isolation of habitat patches influence the genetic variation of local populations of the Dupont's lark (Chersophilus duponti), an endangered songbird. An information-theoretic approach to model selection allowed us to address the importance of interactions between habitat variables, an aspect seldom considered in fragmentation studies, but which explained up to 65% of the variance in genetic parameters. Genetic diversity and inbreeding were influenced by the size of local populations depending on their degree of isolation, and genetic differentiation was positively related to isolation. We then identified a minimum local population of 19 male territories and a maximum distance of 30km to the nearest population as thresholds from which genetic erosion becomes apparent. Our results alert on possibly misleading conclusions and suboptimal management recommendations when only additive effects are taken into account and encourage the use of most explanatory but easy-to-measure variables for the evaluation of genetic risks in conservation programmes.Peer Reviewe

Restricted gene flow and genetic drift in recently fragmented populations of an endangered steppe bird

Identifying the genetic processes derived from habitat fragmentation is critical for the conservation of endangered species. We conducted an integrated analysis of genetic patterns in the endangered Dupont’s lark (Chersophilus duponti), a circum-Mediterranean songbird threatened by the loss and fragmentation of natural steppes in recent decades. After sampling all the remaining Spanish populations and the two clos¬est North African ones, we found that the Mediterranean Sea acts as a major barrier against gene flow and that recent habitat fragmentation is isolating Spanish populations at different spatial scales. While we found a historical signal of gene flow among Spanish regions, a coalescent model supported that the ancestral panmictic population is evolving into several different units in the absence of current gene flow, genetic drift being more intense in the smaller and more isolated populations. Moreover, small-scale spa¬tial autocorrelation analyses showed that genetic differentiation is also acting within populations. The spatial genetic structure, significant levels of inbreeding and high relatedness within patches raise con¬cerns on the viability of most of the extant populations. We highlight the urgency for steppe patches to be protected, expanded and reconnected, considering the genetic clusters identified here rather than the previously considered eco-geographic regions occupied by the species. Meanwhile, translocations could be considered as a complementary, faster management action to attenuate the crowding and genetic effects of population fragmentation and the extinction risk of small populations without compromising the current local adaptations, culture diversity and genetic clusters already known for the species.Peer Reviewe

Isolation and characterization of microsatellite loci for the endangered Midwife Betic toad Alytes dickhilleni (Discoglossidae)

We have developed eleven polymorphic micro- satellite loci for the amphibian Alytes dickhilleni using an enriched-library approach. We detected 98 alleles in 50 individuals genotyped (mean number of alleles per locus was 8.91) in two different populations in South East Spain. Expected heterozygosities ranged from 0.324 to 0.891 in one population (Arroyo Guadahornillos) and 0.424–0.909 in the other population (Cueva Paria). The levels of poly- morphism of the developed markers render them readily applicable for population genetic studies of diversity, structure, and migration.Peer Reviewe

Religious habits of patients submitted to amputation

Background. Religious habits constitute an important component in many people's lives, and this importance seems to increase with the onset of middle age. The aim of this study was to identify the existence of religious habits, before and after surgery, of patients who underwent amputation of lower limbs. Material and methods. Twelve patients, eleven men and one woman, were included in the study, with ages ranging from 24 to 73 years (mean age 61.5 years). The method of evaluation was by means of an individual questionnaire, especially elaborated for this research, regarding some religious customs classified as either institutional or non-institutional. The patients were requested to complete the questionnaire before the surgery, immediately after the surgery before being released from hospital, and when they returned for a check-up. Normal ethical considerations were complied with including approval of the local Ethics Research Committee. For statistical analysis, percentages were utilized. Results. A total of 83.33% said they were Catholics, 8.33% said they were spiritualists, and 8.33% reported to be protestants. The majority (91.66%) reported that religion was an important factor in the process of accepting the illness. Before the amputation, their religious habits included praying (91.66%), frequenting church (83.33%), watching or listening to religious services (25%), contact with friends from the church (83.33%), and participating in religious events (41.66%). Conclusions. Religious habits help patients deal with the stress caused by amputation. Even if some of the habits are reduced due to with the purpose of providing some acceptance of the act of surgery and to reduce the symptoms of stress caused

Shaking earth: Non-linear seismic processes and the second law of thermodynamics: A case study from Canterbury (New Zealand) earthquakes

We would like to express our gratitude to GeoNet for making available the data used in this work. This work was partially sup-ported by the RNM104 and RNM194 (Research Groups belonging to Junta de Andalucia, Spain) , the Spanish National Projects [grant project PID2019-109608GB-I00] , and the Junta de Andalucia Project [grant project A-RNM-421-UGR18] . English language editing was performed by Tornillo Scientific.Earthquakes are non-linear phenomena that are often treated as a chaotic natural processes. We propose the use of the Second Law of Thermodynamics and entropy, H, as an indicator of the equilibrium state of a seismically active region (a seismic system). In this sense, in this paper we demonstrate the exportability of first principles (e.g., thermodynamics laws) to others scientific fields (e.g., seismology). We suggest that the relationship between increasing H and the occurrence of large earthquakes reflects the irreversible transition of a system. From this point of view, a seismic system evolves from an unstable initial state (due to external stresses) to a state of reduced stress after an earthquake. This is an irreversible transition that entails an increase in entropy. In other words, a seismic system is in a metastable situation that can be characterised by the Second Law of Thermodynamics. We investigated two seismic episodes in the Canterbury area of New Zealand: the 2010 Christchurch earthquake (M = 7.2) and the 2016 Kaikoura earthquake (M = 7.8). The results are remarkably in line with our theoretical forecasts. In other words, an earthquake, understood as an irreversible transition, must results in an increase in entropy.Research Groups belonging to Junta de Andalucia, Spain RNM104- RNM194Spanish National Projects PID2019-109608GB-I00Junta de Andalucia A-RNM-421-UGR1

Analysis of relatedness and determination of the source of founders in the captive bearded vulture, Gypaetus barbatus, population

Genetic relatedness among founders is a vital parameter in the management of captive populations as kin structure can have a significant effect on subsequent population structure. Methods for inferring relatedness from microsatellite markers have all been developed for natural populations; their applicability to captive populations with unknown founder origins needs therefore testing. We used information derived from 14 microsatellites in 177 individuals and Queller and Goodnight’s approach, to estimate relatedness in the captive bearded vulture population and to test the assumption of unrelated founders. Mean relatedness of known parent–offspring, fullsib and half-sib pairs within the captive population were in agreement with theoretical distributions. Pairwise relatedness values among the founders had a mean of −0.051 (SE ± 0.007) and their distribution did only differ marginally from the one found in the natural Pyrenean population. A maximum likelihood approach was used to determine the likelihood of founder pairs to be as closely related as full-sibs or parent–offspring. These results were combinedwith data from 268 bp mitochondrialDNA control region sequences and studbook information.We could exclude a close relationship among the majority of the 36 successfully reproducing founders. Our study therefore removes management concerns about hidden problems of inbreeding and inbreeding depression. It demonstrates the applicability of relatedness estimates based on microsatellite allele frequency data even in captive populations. Furthermore, we verified studbook information on the origin of two founders from the Pyrenees, and show the value of assignment tests based on microsatellites for deducing founder origins and their important role in future monitoring projects.Peer reviewe

Heterozygosity-fitness correlations and inbreeding depression in two critically endangered mammals

The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding-fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity-fitness correlations). However, it has been suggested recently that heterozygosity-fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity-fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding-fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding.Peer Reviewe

Disulfide Engineered Lipase to Enhance the Catalytic Activity: A Structure-Based Approach on BTL2

Enhancement, control, and tuning of hydrolytic activity and specificity of lipases are major goals for the industry. Thermoalkaliphilic lipases from the I.5 family, with their native advantages such as high thermostability and tolerance to alkaline pHs, are a target for biotechnological applications. Although several strategies have been applied to increase lipases activity, the enhancement through protein engineering without compromising other capabilities is still elusive. Lipases from the I.5 family suffer a unique and delicate double lid restructuration to transition from a closed and inactive state to their open and enzymatically active conformation. In order to increase the activity of the wild type Geobacillus thermocatenulatus lipase 2 (BTL2) we rationally designed, based on its tridimensional structure, a mutant (ccBTL2) capable of forming a disulfide bond to lock the open state. ccBTL2 was generated replacing A191 and F206 to cysteine residues while both wild type C64 and C295 were mutated to serine. A covalently immobilized ccBTL2 showed a 3.5-fold increment in esterase activity with 0.1% Triton X-100 (2336 IU mg-1) and up to 6.0-fold higher with 0.01% CTAB (778 IU mg-1), both in the presence of oxidizing sulfhydryl agents, when compared to BTL2. The remarkable and industrially desired features of BTL2 such as optimal alkaliphilic pH and high thermal stability were not affected. The designed disulfide bond also conferred reversibility to the enhancement, as the increment on activity observed for ccBTL2 was controlled by redox pretreatments. MD simulations suggested that the most stable conformation for ccBTL2 (with the disulfide bond formed) was, as we predicted, similar to the open and active conformation of this lipase.Financial and logistic support from Colombian Universidad del Valle and COLCIENCIAS (CI 71083-Grant 745-2016-Project 110671250425), Spanish CICYT project BIO-2005-6018576, BFU2017-90030-P, and BFU2011-25326, B. Di G. In addition, thanks to the Spanish MINECO for a FPU fellowship.S

New biotechnological perspectives of a NADH oxidase variant from Thermus thermophilus HB27 as NAD+-recycling enzyme

<p>Abstract</p> <p>Background</p> <p>The number of biotransformations that use nicotinamide recycling systems is exponentially growing. For this reason one of the current challenges in biocatalysis is to develop and optimize more simple and efficient cofactor recycling systems. One promising approach to regenerate NAD⁺pools is the use of NADH-oxidases that reduce oxygen to hydrogen peroxide while oxidizing NADH to NAD⁺. This class of enzymes may be applied to asymmetric reduction of prochiral substrates in order to obtain enantiopure compounds.</p> <p>Results</p> <p>The NADH-oxidase (NOX) presented here is a flavoenzyme which needs exogenous FAD or FMN to reach its maximum velocity. Interestingly, this enzyme is 6-fold hyperactivated by incubation at high temperatures (80°C) under limiting concentrations of flavin cofactor, a change that remains stable even at low temperatures (37°C). The hyperactivated form presented a high specific activity (37.5 U/mg) at low temperatures despite isolation from a thermophile source. Immobilization of NOX onto agarose activated with glyoxyl groups yielded the most stable enzyme preparation (6-fold more stable than the hyperactivated soluble enzyme). The immobilized derivative was able to be reactivated under physiological conditions after inactivation by high solvent concentrations. The inactivation/reactivation cycle could be repeated at least three times, recovering full NOX activity in all cases after the reactivation step. This immobilized catalyst is presented as a recycling partner for a thermophile alcohol dehydrogenase in order to perform the kinetic resolution secondary alcohols.</p> <p>Conclusion</p> <p>We have designed, developed and characterized a heterogeneous and robust biocatalyst which has been used as recycling partner in the kinetic resolution of <it>rac</it>-1-phenylethanol. The high stability along with its capability to be reactivated makes this biocatalyst highly re-useable for cofactor recycling in redox biotransformations.</p