Identifying Mozambique's most critical areas for plant conservation: An evaluation of protected areas and Important Plant Areas

Successful protected area networks must represent biodiversity across taxonomic groups. However, too often plant species are overlooked in conservation planning, and the resulting protected areas may, as a result, fail to encompass the most important sites for plant diversity. The Mozambique Tropical Important Plant Areas project sought to promote the conservation of Mozambique's flora through the identification of Important Plant Areas (IPAs). Here, we use the Weighted Endemism including Global Endangerment (WEGE) index to identify the richest areas for rare and endemic plants in Mozambique and subsequently evaluate how well represented these hotspots are within the current protected area and IPA networks. We also examine the congruence between IPA and protected areas to identify opportunities for strengthening the conservation of plants in Mozambique. We found that high WEGE scores, representing areas rich in endemic/near-endemic and threatened species, predict the presence of IPAs in Mozambique, but do not predict the presence of protected areas. We also find that there is limited overlap between IPAs and protected areas in Mozambique. We demonstrate how IPAs could be an important tool for ensuring priority sites for plant diversity are included within protected area network expansions, particularly following the adoption of the “30 by 30” target agreed within the post-2020 Convention on Biological Diversity framework, with great potential for this method to be replicated elsewhere in the global tropics.     

Stereoselective HPLC bioanalysis of atenolol enantiomers in plasma: Application to a comparative human pharmacokinetic study

An enantioselective HPLC bioassay has been developed relying on extraction of (R)- and (S)-atenolol from alkalinized plasma or serum (pH > 12) into dichloromethane containing 5% (v/v) 1-butanol followed by an achiral derivatization of the drug with phosgene leading to (R)- and (S)-oxazolidine-2-one derivatives. Under these conditions there was quantitative conversion of the acetamido group to the corresponding nitrile. These stable derivatives were separated on a (R,R)-diaminocylohexane-dinitrobenzoyl chiral stationary phase [(R,R)-DACH-DNB] using dichloromethane/methanol 98/2 as mobile phase. Determination limits of 0.5 ng for (R)- and 0.6 ng for (S)-atenolol could be achieved using fluorimetric detection. The assay was applied to a human pharmacokinetic study which was performed in a randomized cross-over, double-blind fashion in 12 healthy volunteers, administering single oral doses of 100 mg (R,S)-, 50 mg (R)-, and 50 mg (S)-atenolol AUC_0–24 and C_max values of (R)-atenolol were slightly but significant higher than those of (S)-atenolol. The R/S ratios were 1.09 for AUC(R)/AUC(S) and 1.03 for C_max (R)/C_max(S) (P < 0.01) respectively after administration of the racemic drug. However, there were no differences between AUC, C_max, and t_½ values of each enantiomer, whether they were administered as single enantiometers or in the form of its racemic mixture. © 1993 Wiley-Liss, Inc.     

Comparison between aquatic and terrestrial locomotions of the leatherback sea turle (Dermochelys coriacea)

Kinematic characteristics of the fore- and hindlimb displacements during terrestrial and aquatic locomotions in juvenile marine turtles Dermochelys coriacea are compared. Modulations of the spatial displacements of the limbs and durations of the stance and swing phases are analysed in relationship with the constraints of the aquatic and terrestrial environments. The stance and swing phases used for describing the aquatic locomotion are re-evaluated in the light of the spatial displacements of the forelimbs during complete beating cycles.     

Diversity and evolution of leaflet anatomical characters in the Pterocarpus clade (Fabaceae: Papilionoideae)

Journal of Plant Research - The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize...     

Preparation of Insect Chromosomes for Immunolabeling

We describe a method for isolating chromosomes from testes of the desert locust, Schistocerca gregaria, and their subsequent incubation with antibodies directed against chromosomal proteins. The procedure involves hypotonic pretreatment of the germ cells, centrifugation onto coverslips in a cytocentrifuge and immunolabeling, while still unfixed, using a chromatin-stabilizing buffer. In the present case, an antibody specific for the acetylated isoforms of his tone H4 was tested. After the antibody treatment, the preparations are fixed using formaldehyde, stained with a DNA-specific fluorescent dye and mounted. Analysis of the preparations revealed good preservation of chromosome structure in prophase spermatogonia and late prophase I spermatocytes. Fully condensed chromosomes were not observed and are probably lost during preparation. The bright fluorescence of the autosomes indicates that the reaction between the antibody against acetylated histone H4 and its chromosomal antigen is not impeded. In contrast, the X univalent remained unstained with the exception of a small terminal band. Thus, cytospin preparations of locust germ cells allow high resolution immunolabeling with antibodies against chromosome-associated proteins.     

A Mild Purification Method for Polysaccharide Binding Membrane Proteins: Phase Separation of Digitonin Extracts to Isolate the Hyaluronate Synthase fromStreptococcussp. in Active Form

A new method was developed to purify the streptococcal hyaluronate synthase in active form to electrophoretic homogeneity. The method is based on the extraction of protoplast membranes with digitonin and a phase separation into an aqueous and a detergent phase induced by addition of polyethylene glycol 6000 at 0°C. Proteins bound to hyaluronate were enriched in the aqueous phase, whereas other membrane proteins resided in the detergent phase. Final purification of the hyaluronate synthase was achieved by ion exchange chromatography.     

Characterization of a cDNA encoding the 55 kDa B regulatory subunit of Arabidopsis protein phosphatase 2A

Type 2A serine/threonine protein phosphatases (PP2A) are key components in the regulation of signal transduction and control of cell metabolism. The activity of these protein phosphatases is modulated by regulatory subunits. While PP2A activity has been characterized in plants, little is known about its regulation. We used the polymerase chain reaction to amplify a segment of a cDNA encoding the B regulatory subunit of PP2A from Arabidopsis. The amplified DNA fragment of 372 nucleotides was used as a probe to screen an Arabidopsis cDNA library and a full-length clone (AtB) of 2.1 kbp was isolated. The predicted protein encoded by AtB is 43 to 46% identical and 53 to 56% similar to its yeast and mammalian counterparts, and contains three unique regions of amino acid insertions not present in the animal B regulatory subunit. Genomic Southern blots indicate the Arabidopsis genome contains at least two genes encoding the B regulatory subunit. In addition, other plant species also contain DNA sequences homologous to the B regulatory subunit, indicating that regulation of PP2A activity by the 55 kDa B regulatory subunit is probably ubiquitous in plants. Northern blots indicate the AtB mRNA accumulates in all Arabidopsis tissues examined, suggesting the protein product of the AtB gene performs a basic housekeeping function in plant cells.     

Repair mechanisms of UV-induced DNA damage in soybean chloroplasts

In order to better understand the biochemical mechanisms of DNA metabolism in chloroplasts, repair of UV induced plastome damage in vivo was determined by exposure of soybean suspension cells to UV light and subsequent quantitation of the damage remaining in nuclear and chloroplast encoded genes with time by quantitative polymerase chain reaction (QPCR). The kinetics of damage rapir in the nuclear rbcS gene suggest that photoreactivation and dark mechanisms are active, while for the plastome encoded psbA gene only a light-dependent repair process was detected which is considerably slower than would be expected for photolyase-mediated photoreactivation.     

Characterization of the peptide-N4-(N-acetylglucosaminyl) asparagine amidase (PNGase Se) fromSilene alba cells

The peptide-N ⁴-(N-acetylglucosaminyl) asparagine amidase (PNGase Se) earlier described [Lhernould S., Karamanos Y., Bourgerie S., Strecker G., Julien R., Morvan H. (1992)Glycoconjugate J 9:191–97] was partially purified from culturedSilene alba cells using affinity chromatography. The enzyme is active between pH 3.0 and 6.5, and is stable in the presence of moderate concentrations of several other protein unfolding chemicals, but is readily inactivated by SDS. Although the enzyme cleaves the carbohydrate from a variety of animal and plant glycopeptides, it does not hydrolyse the carbohydrate from most of the corresponding unfolded glycoproteins in otherwise comparable conditions. The substrate specificity of this plant PNGase supports the hypothesis that this enzyme could be at the origin of the production of unconjugated N-glycans in a suspension medium of culturedSilene alba cells.Abbreviations GlcNAc N-acetylglucosamine - PNGase peptide-N ⁴-(N-acetylglucosaminyl) asparagine amidase - BSA bovine serum albumin - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis - TLC thin layer chromatography - HPAEC-PAD High pH anion exchange chromatography-pulsed amperometric detection