Oceanic rafting by a coastal community

Oceanic rafting is thought to play a fundamental role in assembling the biological communities of isolated coastal ecosystems. Direct observations of this key ecological and evolutionary process are, however, critically lacking. The importance of macroalgal rafting as a dispersal mechanism has remained uncertain, largely owing to lack of knowledge about the capacity of fauna to survive long voyages at sea and successfully make landfall and establish. Here, we directly document the rafting of a diverse assemblage of intertidal organisms across several hundred kilometres of open ocean, from the subantarctic to mainland New Zealand. Multispecies analyses using phylogeographic and ecological data indicate that 10 epifaunal invertebrate species rafted on six large bull kelp specimens for several weeks from the subantarctic Auckland and/or Snares Islands to the Otago coast of New Zealand, a minimum distance of some 400–600 km. These genetic data are the first to demonstrate that passive rafting can enable simultaneous trans-oceanic transport and landfall of numerous coastal taxa.     

Synthesis and preliminary pharmacological evaluation of the four stereoisomers of (2S)-2-(2'-phosphono-3'-phenylcyclopropyl)glycine, the first class of 3'-substituted trans C1'-2'-2-(2'-phosphonocyclopropyl)glycines

Four stereoisomers of (2S)-2-(2'-phosphono-3'-phenylcyclopropyl)glycine were synthesized by a stereocontrolled synthetic procedure and evaluated as mGluRs ligands. The (2S,1'R,2'S,3'R)-isomer (PPCG-2) showed to be a group III mGluRs selective ligand endowed with a moderate potency as mGluR4/mGluR6 agonist.     

High-throughput optimization of surfaces for antibody immobilization using metal complexes

Using a high-throughput surface discovery approach, we have generated a 1600-member library of metal-containing surfaces and screened them for antibody binding potential. The surface library assembly involved graft modification of argon plasma-treated polyvinylidenedifluoride (PVDF) membranes with alternating maleic anhydride-styrene copolymer followed by anhydride ring opening with a range of secondary amines and microarray contact printing of transition metal complexes. The microarrays of metal-containing surfaces were then tested for their antibody binding capacity by incubation with a biotinylated mouse antibody in a chemiluminescence assay. A total of 11 leads were identified from the first screen, constituting a "hit" rate of 0.7%. A smaller 135-member surface library was then synthesized and screened to optimize existing hits and generate additional leads. To demonstrate the applicability of these surfaces to other formats, high-binding surface leads were then transferred onto Luminex beads for use in a bead flow cytometric immunoassay. The novel one-step antibody coupling process increased assay sensitivity of a Luminex tumor necrosis factor immunoassay. These high-binding surfaces do not require prior incorporation of polyhistidine tags or posttreatments such as oxidation to achieve essentially irreversible binding of immunoglobulin G.     

Seed Predation by Rodents and Implications for Plant Recruitment in Defaunated Atlantic Forests

Rodents are known to perform post‐dispersal seed predation in tropical rain forest, but there is little information on the identity of these seed predators and how they select their seeds. Using cafeteria experiments, we found that seed mass, rodent body mass, and the ratio of seed/rodent mass were determinants of seed consumption.     

Design and studies of novel polyoxysterol-based porphyrin conjugates

New types of steroid-porphyrin conjugates derived from 20-hydroxyecdysone (20E) and 24-epibrassinolide (EBl) were synthesized. An exceptional regioselectivity in the reaction of both steroids with porphyrin boronic acids was found to give side-chain-conjugated boronic esters as sole products. UV-Vis-, fluorescence and NMR spectroscopy yielded similar data for all the studied compounds confirming the solvent driven supramolecular assembly with formation of J-aggregates. CD measurements of water diluted solutions showed a clear difference between 20E and EBl conjugates. The latter showed a strong supramolecular chirality, whereas 20E J-aggregates did not.     

Properties of the Probiotic Strain Lactobacillus plantarum 8-RA-3 Grown in a Biofilm by Solid Substrate Cultivation Method

The biofilm formation took place in 48?h within the solid substrate cultivation of Lactobacillus plantarum 8-RA-3 strain on the wheat bran saturated with the MRS medium. The drying of the bran fermented by lactobacilli resulted in a decrease in the number of colony-forming units (CFU) from 23.0?×?10⁸ to 6.9?×?10⁵?CFU/g in daily samples and to less than 10⁴?CFU/g in 2- and 3-day samples. However, according to the fluorescence-based live/dead assay data, more than 40?% of the non-cultured bacteria were viable. As a result of mice kept on a diet with the introduction of bran fermented by Lact. plantarum 8-RA-3 for 72?h into the fodder, a recovery of normal level of intestinal lactobacilli, inhibited by administration of antibiotic was noted. The strain genetically identical to the Lact. plantarum 8-RA-3 was isolated from the feces of these mice. The results indicate that solid substrate cultivated Lact. plantarum 8-RA-3 strain formed a biofilm. Once dried and transferred into a non-cultured state, biofilm cells retained its viability and biological activity.     

No carrier added synthesis of O-(2'-[18F]fluoroethyl)-L-tyrosine via a novel type of chiral enantiomerically pure precursor, NiII complex of a (S)-tyrosine Schiff base

O-(2′-[¹⁸F]fluoroethyl)-l-tyrosine ([¹⁸F]FET) has gained much attention as a promising amino acid radiotracer for tumor imaging with positron emission tomography (PET) due to favorable imaging characteristics and relatively long half-life of ¹⁸F (110 min) allowing remote-site application. Here we present a novel type of chiral enantiomerically pure labeling precursor for [¹⁸F]FET, based on NiII complex of a Schiff’s base of (S)-[N-2-(N′-benzylprolyl)amino]benzophenone (BPB) with alkylated (S)-tyrosine, Ni-(S)-BPB-(S)-Tyr-OCH2CH2X (X = OTs (3a), OMs (3b) and OTf (3c)). A series of compounds 3a–c was synthesized in three steps from commercially available reagents. Non-radioactive FET as a reference was prepared from 3a in a form of (S)-isomer and (R,S) racemic mixture. Radiosynthesis comprised two steps: (1) n.c.a. nucleophilic fluorination of 3a–c (4.5–5.0 mg) in the presence of either Kryptofix 2.2.2.or tetrabutylammonium carbonate (TBAC) in MeCN at 80 °C for 5 min, followed by (2) removal of protective groups by treating with 0.5 M HCl (120 °C, 5 min). The major advantages of this procedure are retention of enantiomeric purity during the ¹⁸F-introduction step and easy simultaneous deprotection of amino and carboxy moieties in 3a–c. Radiochemically pure [¹⁸F]FET was isolated by semi-preparative HPLC (C18 μ-Bondapak, Waters) eluent aq 0.01 M CH₃COONH₄, pH 4/C₂H₅OH 90/10 (v/v). Overall synthesis time operated by Anatech RB 86 laboratory robot was 55 min. In a series of compounds 3a–c, tosyl derivative 3a provided highest radiochemical yield (40–45%, corrected for radioactive decay). Enantiomeric purity was 94–95% and 96–97%, correspondingly, for Kryptofix and TBAC assisted fluorinations. The suggested procedure involved minimal number of synthesis steps and suits perfectly for automation in the modern synthesis modules for PET radiopharmaceuticals. Preliminary biodistribution study in experimental model of turpentine-induced aseptic abscess and Glioma35 rat’s tumor (homografts) in Wistar rats has demonstrated the enhanced uptake of radiotracer in the tumor area with minimal accumulation in the inflamed tissues.     

A transformation procedure for recalcitrant tomato by addressing transgenic plant-recovery limiting factors

Agrobacterium tumefaciens technology is the battle horse for tomato genetic transformation. However, tomato varieties with low regeneration capacity are very difficult to transform. In the past, tomato transformation through Agrobacterium infection was focused on varieties capable of high regeneration yield, while successful transformation of low regenerable cultivars has not been reported. The genotype response to tissue culture conditions is believed to drive the frequency of regeneration of transgenic plant, whereas the capacity for cell proliferation could determine the transformation efficiency through this technology. The Campbell-28 cultivar is an example of constraints arising from a high morphogenetic potential with low conversion compared to normal plants. In the present work the roles that contribute to improved transgenic plant recovery from this recalcitrant variety were explored for factors like Agrobacterium concentration and antibiotics for bacterial removal and transformant selection. Analysis of the efficiency from independent transformation experiments revealed a more than twofold increase of transformant regeneration after selection on ammonium glufosinate compared to kanamycin selection, showing a transformation efficiency of 21.5%.