The frozen zoo concept

Biologic material from exotic species is difficult to obtain for scientists. Yet much depends on the availability of such materials for a better understanding of evolutionary relationships and genetics of animals. Zoos have an obligation to participate in the safeguarding of some of these tissues by preserving cells, serum, and organs under optimal conditions. This paper describes the state of the frozen tissue-cell bank at San Diego Zoo and examines possible future directions for the collection of essential materials.     

Characterization of dermatan sulfate in mucopolysaccharidosis VI Evidence for the absence of hyaluronidase-like enzymes in human skin fibroblasts

Dermatan sulfate-chondroitin sulfate copolymers with a high content of dermatan sulfate are stored in cultured human skin fibroblasts from patients affected with mucopolysaccharidosis VI (Maroteaux-Lamy disease). Characterization of the storage material provided evidence that hyaluronidase-like enzymes are not present in these fibroblasts. This is based on the following observations: (i) dermatan sulfate chains stored intracellularly show no reduction of molecular size as compared with intact chains isolated from the extracellular space; (ii) the stored dermatan sulfate chains lack reducible end groups generated by endoglycosidases; (iii) homogenates of human skin fibroblasts do not degrade hyaluronate and (iv) the stored dermatan sulfate chains are degraded by testes hyaluronidase.     

Arion transsylvanus (Mollusca,Pulmonata, Arionidae): rediscovery of a cryptic species

Jordaens, K., Pinceel, J., Van Houtte, N., Breugelmans, K. & Backeljau, T. (2010). Arion transsylvanus (Mollusca, Pulmonata, Arionidae): rediscovery of a cryptic species. —Zoologica Scripta, 39, 343–362. Cryptic species are abundant among invertebrates and are often hard to recognise. Molecular markers are an extremely useful tool to delineate cryptic taxa, although they should be applied with caution because different genes and techniques may yield different outcomes. We illustrate how cross‐validation by molecular and morphological data can be applied to optimise taxonomic interpretations when cryptic species are involved. This is performed for the terrestrial slug Arion subfuscus species complex which represents a historical ‘taxonomic garbage can’. Gonad morphology, allozymes and mtDNA data consistently showed that slugs from Romania and a location in E Poland represent a strongly differentiated taxon within this complex. These slugs are therefore formally redescribed and assigned to A. transsylvanus Simroth 1885 ; a forgotten nominal taxon from Transylvania. Diagnostic characters, including DNA sequences for the mitochondrial 16S rDNA are presented. Animals with the morphology of A. brunneus Lehmann 1862 , a nominal taxon which has also been reported from Romania, have the gonad type, allozyme alleles and 16S rDNA haplotypes of either A. fuscus, A. subfuscus or A. transsylvanus. Therefore, A. brunneus is regarded as a colour morph shared by several species and hence, A. transsylvanus is probably the only A. subfuscus‐like species in the Romanian Carpathians.     

Chemoenzymatic large-scale preparation of homochiral bicyclo[3.2.0]hept-2-en-6-one

Summary Both enantiomers of bicyclo[3.2.0]hept-2-en-6-one —precursors of Corey's lactone — were obtained in >98% e.e. by means of an enzymatic resolution of (±)-endo-bicyclo[3.2.0]hept-2-en-6-yl acetate usingPseudomonas fluorescens lipase.     

The use of on‐animal acoustical recording devices for studying animal behavior

Audio recordings made from free‐ranging animals can be used to investigate aspects of physiology, behavior, and ecology through acoustic signal processing. On‐animal acoustical monitoring applications allow continuous remote data collection, and can serve to address questions across temporal and spatial scales. We report on the design of an inexpensive collar‐mounted recording device and present data on the activity budget of wild mule deer (Odocoileus hemionus) derived from these devices applied for a 2‐week period. Over 3300 h of acoustical recordings were collected from 10 deer on their winter range in a natural gas extraction field in northwestern Colorado. Analysis of a subset of the data indicated deer spent approximately 33.5% of their time browsing, 20.8% of their time processing food through mastication, and nearly 38.3% of their time digesting through rumination, with marked differences in diel patterning of these activities. Systematic auditory vigilance was a salient activity when masticating, and these data offer options for quantifying wildlife responses to varying listening conditions and predation risk. These results (validated using direct observation) demonstrate that acoustical monitoring is a viable and accurate method for characterizing individual time budgets and behaviors of ungulates, and may provide new insight into the ways external forces affect wildlife behavior.     

Photothermal Catalytic Gel Featuring Spectral and Thermal Management for Parallel Freshwater and Hydrogen Production

Desalination processes often require large amounts of energy to create clean water, and vice versa for the generation of energy. This interdependence creates a tension between the two essential resources. Current research focuses on one or the other, which exacerbates water‐energy stress, while few tackle both issues jointly. Herein, a low‐carbon technology, H₂O–H₂ co‐generation system that enables concurrent steady freshwater and clean energy output is reported. The water‐energy coupled technology features a spectrally and thermally managed solar harvesting gel for photoredox and photoheating effects. This photothermal catalytic gel exploits interfacial solar heating for heat confinement, and localized plasmonic heating at the catalyst active sites to remarkably improve water and hydrogen production, thus maximizing energy value per area. To this end, a stand‐alone renewable solar desalination system is successfully demonstrated for parallel production of freshwater and hydrogen under natural sunlight. By doing so, the water–energy nexus is transformed into a synergistic bond that offers opportunities to better meet expected demand rather than acting in competition.     

Cell membrane permeabilization via connexin hemichannels in living and dying cells

Vertebrate cells that express connexins likely express connexin hemichannels (Cx HCs) at their surface. In diverse cell types, surface Cx HCs can open to serve as a diffusional exchange pathway for ions and small molecules across the cell membrane. Most cells, if not all, also express pannexins that form hemichannels and increase the cell membrane permeability but are not addressed in this review. To date, most characterizations of Cx HCs have utilized cultured cells under resting conditions have and revealed low open probability and unitary conductance close to double that of the corresponding gap junction channels. In addition, the cell membrane permeability through Cx HCs can be markedly affected within seconds to minutes by various changes in the intra and/or extracellular microenvironment (i.e., pH, pCa, redox state, transmembrane voltage and intracellular regulatory proteins) that affect levels, open probability and/or (single channel) permeability of Cx HC. Net increase or decrease in membrane permeability could result from the simultaneous interaction of different mechanisms that affect hemichannels. The permeability of Cx HCs is controlled by complex signaling cascades showing connexin, cell and cell stage dependency. Changes in membrane permeability via hemichannels can have positive consequences in some cells (mainly in healthy cells), whereas in others (mainly in cells affected by acquired and/or genetic diseases) hemichannel activation can be detrimental.     

Purification of TAXI-like Endoxylanase Inhibitors from Wheat (Triticum Aestivum L.) Whole Meal Reveals a Family of Iso-forms

An affinity chromatography method has been developed for purification of endoxylanase inhibitors concentrated by cation exchange chromatography from wheat whole meal and is based on immobilisation of a Bacillus subtilis family 11 endoxylanase on N -hydroxysuccinimide activated Sepharose 4 Fast Flow. When followed by high-resolution cation exchange chromatography, the purification of seven TAXIs, Triticum aestivum L. endoxylanase inhibitors was achieved so extending the number of such proteins known to date (TAXI I and II). Based on their inhibition activities against a B. subtilis family 11 and an Aspergillus niger family 11 endoxylanase, six TAXI I- and only one TAXI II-like inhibitor could be distinguished. The first type of endoxylanase inhibitor is active against both endoxylanases and the second type only has significant activity against the B. subtilis endoxylanase.     

Plant community and phylogenetic shifts in acid seep springs over 49 years following Microstegium vimineum invasion

Plant Ecology - Community composition and diversity can change following exotic invasion. We tested the extent to which acid seep spring communities in southern Illinois had changed in composition...