Global patterns of fern species diversity: An evaluation of fern data in GBIF

Despite that several studies have shown that data derived from species lists generated from distribution occurrence records in the Global Biodiversity Information Facility (GBIF) are not appropriate for those ecological and biogeographic studies that require high sampling completeness, because species lists derived from GBIF are generally very incomplete, Suissa et al. (2021) generated fern species lists based on data with GBIF for 100 km × 100 km grid cells across the world, and used the data to determine fern diversity hotspots and species richness–climate relationships. We conduct an evaluation on the completeness of fern species lists derived from GBIF at the grid–cell scale and at a larger spatial scale, and determine whether fern data derived from GBIF are appropriate for studies on the relations of species composition and richness with climatic variables. We show that species sampling completeness of GBIF is low (<40%) for most of the grid cells examined, and such low sampling completeness can substantially bias the investigation of geographic and ecological patterns of species diversity and the identification of diversity hotspots. We conclude that fern species lists derived from GBIF are generally very incomplete across a wide range of spatial scales, and are not appropriate for studies that require data derived from species lists in high completeness. We present a map showing global patterns of fern species diversity based on complete or nearly complete regional fern species lists.     

Characterization of a new tyrosinase from Pycnoporus species with high potential for food technological applications

AIMS: Tyrosinase production by Pycnoporus cinnabarinus and Pycnoporus sanguineus was screened among 20 strains originating from various geographical areas, particularly from tropical environments. The tyrosinase from the most efficient strain was purified and characterized and tested for food additive applications. METHODS AND RESULTS: Monophenolase and diphenolase activities of tyrosinase were measured from cell lysate from the 20 Pycnoporus strains, for 8-10 days of cultivation. The strain P. sanguineus CBS 614.73 showed the highest productivity (45.4 and 163.6 U g(-1) protein per day for monophenolase and diphenolase respectively). P. sanguineus CBS 614.73 tyrosinase was purified from concentrated cell lysate, anion-exchange, size-exclusion and hydroxyapatite chromatography, with a final yield of 2% and a purification factor of 35-38. The pure enzyme was a monomere with a molecular mass of 45 kDa and it showed four isoforms or isoenzymes with pI between 4.5-5. No N-glycosylation was found. The N-terminal amino acid sequence was IVTGPVGGQTEGAPAPNR. The enzyme was shown to be almost fully active in a pH range of 6-7, in a large temperature range (30-70 degrees C), and was stable below 60 degrees C. The main kinetic constants were determined. The tyrosinase was able to convert p-tyrosol and p-coumaric acid into hydroxytyrosol and caffeic acid, respectively, and it could also catalyse the cross-linking formation of a model protein. CONCLUSIONS: Among the genus Pycnoporus, known for the production of laccase, the strain P. sanguineus CBS 614.73 was shown to produce one other phenoloxidase, a new monomeric tyrosinase with a specific activity of 30 and 84 U mg(-1) protein for monophenolase and diphenolase respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: This study identified P. sanguineus CBS 614.73 as a potential producer of a tyrosinase which demonstrated effectiveness in the synthesis of antioxidant molecules and in protein cross-linking.     

Lectins of Dryopteris Adans fern species

Lectin activity of three ferns species (Dryopteris bushiana Fom., D. laeta (Kom.) C. Chr, D. pseudomas (Wollaston) Holub et Pouzar) has been studied. We used hemagglutination reaction albumin and globulin fractions of fronds and rhizomes extracts with rat erythrocytes. The frond extract of D. pseudomas have shown higher activity as compared with other extracts. The lectin activity of D. laeta leaves was absent. The rhizomes of all three fern species could be characterized as high activity. Based on lectin activity the species were placed as follows order: D. buschiana > D. pseudomas > D. laeta. The dependence with lectin activity and elements (Mn, Fe, Cu, Ni, Zn, Pb, Rb, Sr) content were not found.     

Photosynthesis limitations in three fern species

Maximum photosynthesis rates in ferns are generally lower than those of seed plants, but little is known about the limiting factors, which are crucial to understand the evolution of photosynthesis in land plants. To address this issue, a gas exchange/chlorophyll fluorescence analysis was performed in three fern species spanning high phylogenetic range within Polypodiopsida (Osmunda regalis, Blechnum gibbum and Nephrolepis exaltata) to determine their maximum net photosynthesis (A_N), stomatal (g_s) and mesophyll (g_m) conductances to CO₂, and the maximum velocity of carboxylation (V_c,max). The in vitro Rubisco specificity factor (S_C/O) was also determined. All three species had values for S_C/O similar to those typical of seed plants, but values of A_N, g_s, g_m and V_c,max were within the lowest range of those observed in seed plants. In addition, g_s was unresponsive to light and CO₂, as already described in other fern species. On the contrary, g_m varied with changes CO₂. A quantitative photosynthesis limitation analysis suggested that early land plants (ferns) presented not only stomatal limitations—which were less adjustable to the environment—but also restricted g_m and V_c,max, resulting in limited maximum photosynthesis rates.     

A new marsilealean fern species from the Early Cretaceous of Jordan

Leaflets of Marsileaceae are described from the Albian (Early Cretaceous) strata of Jordan. The fossils are from the Jarash Formation (Kurnub Group) and are found in fluvial sediments along with water lily leaves. The small wedge-shaped leaves have dichotomous veins that anastomose and form a marginal vein. Based on comparisons to living genera, Marsileaceaephyllum mahisensis Hu, Taylor, Brenner et Basha, n. sp., is most similar to Marsilea, in particular, with terrestrial leaflet forms; yet, it is distinct from living and fossil species by its small size and the few dichotomously branched middle veins that have a monopodial course. In addition, a single similar-veined smaller leaf with a retuse apex is thought to be a juvenile leaf of the same species. This is the first megafossil evidence of the family from Africa/Arabian Peninsula.     

Assessing New Zealand fern diversity from spatial predictions of species assemblages

The utility of explicit spatial predictions for biodiversity assessment is investigated with New Zealand fern flora. Distributions of 43 species were modelled from climatic and landform variables and predicted across New Zealand using generalised additive models (GAM). An original package of functions called generalised regression analysis and spatial prediction (GRASP) was developed to perform the analyses. On average, for the 43 models, the contributions of environmental variables indicate that mean annual temperature is the most important factor at this broad regional scale. Both annual solar radiation and its seasonality had higher correlations than temperature seasonality. Measures of water availability such as ratio of rainfall to potential evapotranspiration, air saturation deficit and soil water deficit presented significant contributions. Lithology was a better predictor than slope and drainage. These results are similar to those obtained from analyses of the distributions of New Zealand tree species and are consistent with the hypothesis that both tree and fern diversity are highest on sites conducive to high productivity. In order to identify hotspots of fern diversity, spatial predictions of individual species were summed up. The resulting map gave a very similar result to the direct prediction of their corresponding richness (number of species by plot out of 43 spp.). As a consequence, and where individual species models were not all available, the number of species within different species assemblages was directly modelled. Predicted richness hotspots of total species (out of 122 spp.), selected species (out of 43 and 21 spp.) and common species (out of 23 spp.) present very similar spatial patterns and are highly correlated. Richness of uncommon species (out of 39 spp.) was also accurately predicted, but presented a different spatial pattern. The number of rare species (out of 60 spp.) was not correctly modelled. Even though the lack of data for rare species clearly limits the application of this approach, fern community composition of more common species can be partially reconstructed from individual species predictions. This case study offers therefore a consistent approach not only for biodiversity hotspots identification, but also for setting targets to biodiversity assessment and restoration programs.     

Heavy metal and arsenic accumulating fern species as potential ecological indicators in As-contaminated abandoned mines

Ferns are good ecological indicators of arsenic accumulation in contaminated abandoned mines. The rhizomes of ferns were analyzed for arsenic and other heavy metals using inductively coupled plasma-mass spectrometry. In addition, we examined the ribulose-bisphosphate carboxylase (rbcL) gene isolated from the indigenous species of ferns at the pithead, tailings and soil sites in the vicinity of the Myoungbong abandoned mine, Republic of Korea. A search of the GenBank database revealed that the predicted amino acid sequence of this gene was homologous with 99% of Pteridium aquilinum As-2 (EU476184), 99% of Deparia petersenii As-6 (EU476188), 97% of Deparia lobatocrenata As-8 (EU476190), and 98% of Deparia conilii As-7 (EU476189). High concentrations of heavy metals (arsenic, 17.6 mg/kg in rhizomes and 2690 mg/kg in soil; copper, 17.1 mg/kg in rhizomes and 40.7 mg/kg in soil; cadmium, 2.9 mg/kg in rhizomes and 12.2 mg/kg in soil; lead, 41.9 mg/kg in rhizomes and 135 mg/kg in soil; zinc, 27.0 mg/kg in rhizomes and 172 mg/kg in soil) were found in P. aquilinum As-2 (EU476184) from the Myoungbong mine area, which may play an important role as ecological indicators of the contaminated areas.     

Mixed mating system in the fern Asplenium scolopendrium: implications for colonization potential

Background and Aims

Human-mediated environmental change is increasing selection pressure for the capacity in plants to colonize new areas. Habitat fragmentation combined with climate change, in general, forces species to colonize areas over longer distances. Mating systems and genetic load are important determinants of the establishment and long-term survival of new populations. Here, the mating system of Asplenium scolopendrium, a diploid homosporous fern species, is examined in relation to colonization processes.

Methods

A common environment experiment was conducted with 13 pairs of sporophytes, each from a different site. Together they constitute at least nine distinct genotypes, representing an estimated approx. 95 % of the non-private intraspecific genetic variation in Europe. Sporophyte production was recorded for gametophytes derived from each parent sporophyte. Gametophytes were grown in vitro in three different ways: (I) in isolation, (II) with a gametophyte from a different sporophyte within the same site or (III) with a partner from a different site.

Key Results

Sporophyte production was highest in among-site crosses (III), intermediate in within-site crosses (II) and was lowest in isolated gametophytes (I), strongly indicating inbreeding depression. However, intragametophytic selfing was observed in most of the genotypes tested (eight out of nine).

Conclusions

The results imply a mixed mating system in A. scolopendrium, with outcrossing when possible and occasional selfing when needed. Occasional intragametophytic selfing facilitates the successful colonization of new sites from a single spore. The resulting sporophyte, which will be completely homozygous, will shed large amounts of spores over time. Each year this creates a bed of gametophytes in the vicinity of the parent. Any unrelated spore which arrives is then selectively favoured to reproduce and contribute its genes to the new population. Thus, while selfing facilitates initial colonization success, inbreeding depression promotes genetically diverse populations through outcrossing. The results provide further evidence against the overly simple dichotomous distinction of fern species as either selfing or outcrossing.     

Precision wildlife medicine: applications of the human‐centred precision medicine revolution to species conservation

The current species extinction crisis is being exacerbated by an increased rate of emergence of epizootic disease. Human‐induced factors including habitat degradation, loss of biodiversity and wildlife population reductions resulting in reduced genetic variation are accelerating disease emergence. Novel, efficient and effective approaches are required to combat these epizootic events. Here, we present the case for the application of human precision medicine approaches to wildlife medicine in order to enhance species conservation efforts. We consider how the precision medicine revolution, coupled with the advances made in genomics, may provide a powerful and feasible approach to identifying and treating wildlife diseases in a targeted, effective and streamlined manner. A number of case studies of threatened species are presented which demonstrate the applicability of precision medicine to wildlife conservation, including sea turtles, amphibians and Tasmanian devils. These examples show how species conservation could be improved by using precision medicine techniques to determine novel treatments and management strategies for the specific medical conditions hampering efforts to restore population levels. Additionally, a precision medicine approach to wildlife health has in turn the potential to provide deeper insights into human health and the possibility of stemming and alleviating the impacts of zoonotic diseases. The integration of the currently emerging Precision Medicine Initiative with the concepts of EcoHealth (aiming for sustainable health of people, animals and ecosystems through transdisciplinary action research) and One Health (recognizing the intimate connection of humans, animal and ecosystem health and addressing a wide range of risks at the animal–human–ecosystem interface through a coordinated, collaborative, interdisciplinary approach) has great potential to deliver a deeper and broader interdisciplinary‐based understanding of both wildlife and human diseases.     

Phytochemicals from the genus Lavandula: a review

Phytochemistry Reviews - The genus Lavandula occurs naturally in the Mediterranean basin and its species are a rich source of phytochemicals. Species of this genus have attracted great interest,...     

Alkaline serine proteases from Helicoverpa armigera: potential candidates for industrial applications

We characterized trypsin‐ and chymotrypsin‐like serine alkaline proteases from cotton bollworm, Helicoverpa armigera, for their probable potential application as additives in various bio‐formulations. Purification was achieved by using hydroxylapatite, DEAE sephadex and CM sephadex columns, which resulted in increased enzyme activity by 13.76‐ and 14.05‐fold for trypsin and chymotrypsin, respectively. Michaelis–Menten constants (K_m) for substrates of trypsin and chymotrypsin, BApNA and SAAPFpNA, were found to be 1.25 and 0.085 mM, correspondingly. Fluorescent zymogram analysis indicated the presence of five trypsin bands with molecular masses of ～21, 25, 38, 40, and 66 kDa and two chymotrypsin bands with molecular masses of ～29 and 34 kDa in SDS‐PAGE. The optimum pH was 10.0 and optimum temperature was 50°C for proteolytic activity for the purified proteases. The proteases were inhibited by synthetic inhibitors such as PMSF, aprotonin, leupeptin, pefabloc, and antipain. TLCK and TPCK inhibited about 94 and 90% of trypsin and chymotrypsin activity, respectively, while EDTA, EGTA, E64, pepstatin, idoacetamide, and bestatin did not affect the enzymes. The purified enzymes exhibited high stability and compatibility with metal ions; oxidizing, reducing, and bleaching agents; organic solvents; and commercial detergents. Short life cycles, voracious feeding behavior, and production of multiple forms of proteases in the midgut with rapid catalytic activity and chemostability can serve H. armigera as an excellent alternative source of industrially important proteases for use as additives in stain removers, detergents, and other bio‐formulations. Identification of enzymes with essential industrial properties from insect species could be a bioresource.     

South Africa: from species cradle to genomic applications

The South African government is committed to science and technology innovation, to establishing a knowledge-based economy and to harnessing life-sciences research for health and economic development. Given the constraints and the early stage of development of the field as a whole in South Africa, we found an impressive amount of research on human genomic variation in this country. Encouragingly, South Africa is beginning to apply genomics to address local health needs, including HIV and tuberculosis (TB) infections. We document a number of initiatives in South Africa that are beginning to study genetic variation within the various local indigenous populations. Other early initiatives focus on pharmacogenetic studies, mutation characterization in individual disease genes and genome-wide association studies. Public engagement in genomic issues is spear-headed by The Africa Genome Education Institute.     

Ribozyme gene therapy: applications for molecular medicine

RNA enzymes--ribozymes--are being developed as treatments for a variety of diseases ranging from inborn metabolic disorders to viral infections and acquired diseases such as cancer. Ribozymes can be used both to downregulate and to repair pathogenic genes. In some instances, short-term exogenous delivery of stabilized RNA is desirable, but many treatments will require viral-mediated delivery to provide long-term expression of the therapeutic catalyst. Current gene therapy applications employ variations on naturally occurring ribozymes, but in vitro selection has provided new RNA and DNA catalysts, and research on trans-splicing and RNase P has suggested ways to harness the endogenous ribozymes of the cell for therapeutic purposes.     

Developments in transgenic technology: applications for medicine

Recent advances in the efficiency of transgenic technology have important implications for medicine. The production of therapeutic proteins from animal bioreactors is well established and the first products are close to market. The genetic modification of pigs to improve their suitability as organ donors for xenotransplantation has been initiated, but many challenges remain. The use of transgenesis, in combination with the method of RNA interference to knock down gene expression, has been proposed as a method for making animals resistant to viral diseases, which could reduce the likelihood of transmission to humans. Here, the latest developments in transgenic technology and their applications relevant to medicine and human health will be discussed.     

Microwave radiometry and its potential applications in biology and medicine: experimental studies.

This paper presents experimental data on : (1) the natural emission of microwave radiation by biological systems, and (2) the effect of drugs as well as microwave radiation on specimen microwave emission. Experiments were conducted on guinea pigs, mice, rabbits, and human subjects. The results were obtained with two different radiometers, one of the correlation type and one of the Dicke type, operating in the X-band at about 9 GHz with a sensitivity of approximately 0.1 degrees K. The results demonstrate the feasibility of this technique and suggestions are made for its use in bilogy, medicine, and in the field of biocommunications.     

Towards the conservation of the Mesozoic relict fern Christensenia: a fern species with extremely small populations in China

The Chinese occurrences of the marattioid fern genus Christensenia have been considered as requiring protection because of its extreme rarity and very small population size. Here, we explored different biological aspects to enable protection of these rare ferns, well known as Mesozoic living fossils. Firstly, we documented the cytology of the Chinese occurrences for the first time. This is the second tetraploid record of Christensenia worth for further studies to confirm its taxonomic status. Secondly, we obtained the first complete plastid genome of this genus, which confirmed the proposed conservatism of the plastid genome structure in marattioid ferns. By comparing the chloroplast genome with other marattioids, we identified several candidate regions to develop highly variable markers to investigate the intra-species diversity of marattioid ferns. Thirdly, phylogenetic analyses of rbcL sequences implied that there are at least two distinct species of Christensenia. Finally, we re-assessed the conservation status of Christensenia in the context of its local and global distribution by assessing specimen information extracted from publications and digitized voucher information. This assessment confirmed the need to obtain more accurate information about the distribution of this genus to assess the status incorporating the disjunct distribution from southern China and India in the North towards the Solomon Islands in the South.