Novel Support (novel + support)

Distribution by Scientific Domains


Selected Abstracts


Rapid evolution in crop-weed hybrids under artificial selection for divergent life histories

EVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2009
Lesley G. Campbell
Abstract When species hybridize, offspring typically exhibit reduced fitness and maladapted phenotypes. This situation has biosafety implications regarding the unintended spread of novel transgenes, and risk assessments of crop-wild hybrids often assume that poorly adapted hybrid progeny will not evolve adaptive phenotypes. We explored the evolutionary potential of early generation hybrids using nontransgenic wild and cultivated radish (Raphanus raphanistrum, Raphanus sativus) as a model system. We imposed four generations of selection for two weedy traits , early flowering or large size , and measured responses in a common garden in Michigan, USA. Under selection for early flowering, hybrids evolved to flower as early as wild lineages, which changed little. These early-flowering hybrids also recovered wild-type pollen fertility, suggesting a genetic correlation that could accelerate the loss of crop traits when a short life cycle is advantageous. Under selection for large size at reproduction, hybrids evolved longer leaves faster than wild lineages, a potentially advantageous phenotype under longer growing seasons. Although early generation hybrid offspring have reduced fitness, our findings provide novel support for rapid adaptation in crop-wild hybrid populations. Biosafety risk assessment programs should consider the possibility of rapid evolution of weedy traits from early generations of seemingly unfit crop-wild hybrids. [source]


Tri(propylene glycol) glycerolate diacrylate cross-linked polystyrene: a new resin support for solid-phase peptide synthesis

CHEMICAL BIOLOGY & DRUG DESIGN, Issue 1 2003
P.G. Sasikumar
Abstract: A highly flexible, mechanically and chemically stable copolymer, tri(propylene glycol) glycerolate diacrylate cross-linked polystyrene (PS-TRPGGDA), was synthesized by the suspension polymerization and employed as a solid support for peptide synthesis. The beaded polymer support containing secondary hydroxyl functional groups in the cross-linker was used as the growth site for peptide synthesis. The procedure is unique and cost-effective in that it avoids the initial functionalization steps required for most of the styrene-based polymer supports. The resin was characterized by 13C-CP-MAS NMR spectroscopy and the morphologic features of the resin were investigated using scanning electron microscopy. Swelling studies conducted on the new support revealed that the PS-TRPGGDA resin undergoes more effective swelling and solvation than PS-DVB resin in all solvents used in peptide synthesis. The efficiency of the new support was demonstrated by synthesizing a ,difficult' sequence Ala-Arg-(Ala)6 -Lys and comparing it with commercially available Merrifield and Sheppard resins. The synthetic efficiency was further demonstrated by the synthesis of a 24-residue NR 2A peptide substrate of calcium/calmodulin-binding peptide. The high yield and purity of the peptide synthesized on the novel support indicates the positive role of the flexible and hydrophilic cross-linking agent in the solid support. [source]


In this issue: Biotechnology Journal 8/2010

BIOTECHNOLOGY JOURNAL, Issue 8 2010
Article first published online: 12 AUG 2010
Biocatalyst microemulsions Pavlidis et al., Biotechnol. J. 2010, 5, 805,812 Enzymes maintain their catalytic activity when hosted in aqueous nanodroplets like reverse micelles. Researchers from Ioannina, Greece, propose the use of water-in-ionic liquid microemulsionbased organogels (w/IL MBGs) as novel supports for the immobilization of lipase B from Candida antarctica and lipase from Chromobacterium viscosum. These novel lipase-containing w/IL MBGs can be effectively used as solid phase biocatalysts in various polar and non-polar organic solvents or ILs, exhibiting up to 4.4-fold higher esterification activity compared to water-in-oil microemulsion-based organogels. The immobilized lipases retain their activity for several hours at 70C, while their half life time is up to 25-fold higher compared to that observed in w/IL microemulsions Biocatalyst cryogelation Bieler et al., Biotechnol. J. 2010, 5, 881,885 Entrapment of biocatalysts in hydrogel beads allows stable operation in otherwise deteriorating solvents. Doing this by cryogelation is a gentle method to extend the scope of biocatalysis. To foster the use of this versatile method, researchers from Aachen, Germany, devised an automated injector for the production of PVA/PEG-enzyme immobilisates. The device consists of a thermostated reservoir connected to a programmable injector nozzle and an agitated receiving bath for the droplets. This lab-scale production unit yields up to 1500 beads with immobilized enzyme per minute with a narrow size distribution and good roundness. Biocatalyst membrane reactor Lyagin et al., Biotechnol. J. 2010, 5, 813,821 Screening of biocatalysts, substrates or conditions in the early stages of bioprocess development requires an enormous number of experiments and is a tedious, expensive and time-consuming task. Currently available screening systems can only be operated in batch or fed-batch mode, which can lead to severe misinterpretations of screening results. Researchers from Berlin, Germany, now developed a novel screening system that enables continuous feeding of substrates and continuous removal of products. A prototype based on the membrane reactor concept was designed and operated for a model reaction, the hydrolysis of cellulose. [source]


Water-in-ionic liquid microemulsion-based organogels as novel matrices for enzyme immobilization

BIOTECHNOLOGY JOURNAL, Issue 8 2010
Ioannis V. Pavlidis
Abstract The use of water-in-ionic liquid microemulsion-based organogels (w/IL MBGs) as novel supports for the immobilization of lipase B from Candida antarctica and lipase from Chromobacterium viscosum was investigated. These novel lipase-containing w/IL MBGs can be effectively used as solid phase biocatalysts in various polar and non-polar organic solvents or ILs, exhibiting up to 4.4-fold higher esterification activity compared to water-in-oil microemulsion-based organogels. The immobilized lipases retain their activity for several hours at 70C, while their half life time is up to 25-fold higher compared to that observed in w/IL microemulsions. Fourier-transform infrared spectroscopy data indicate that immobilized lipases adopt a more rigid structure, referring to the structure in aqueous solution, which is in correlation with their enhanced catalytic behavior observed. [source]