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51.
Paul Messner Max Wellan Wolfgang Kubelka Uwe B. Sleytr 《Applied microbiology and biotechnology》1993,40(1):7-11
After periodate oxidation and incubation with dithiodipropionic acid dihydrazide cross-linking of the crystalline surface layer (S-layer) glycoproteins of Clostridium thermohydrosulfuricum L111-69 and Bacillus alvei CCM 2051 was achieved specifically through the glycan chains. The cross-linked S-layers were used for the immobilization of chemically synthesized, spacer-linked, tumour-associated T-disaccharide [Gal(13)GalNAc]. Electron microscopical evaluation of the resulting conjugates showed densely packed, multilayered S-layer structures loaded with the immobilized ligand. After reductive cleavage of the disulphide bond of dithiodipropionic acid by dithiothreitol, monomeric haptenated S-layer conjugates could be obtained. Both the cross-linked and the monomeric type of conjugate might be useful for assessment of specific immune responses, which, in general, can be elicited by those artificial antigens.
Correspondence to: P. Messner 相似文献
52.
Wolfgang Kaul Uwe Rossow Carl-Christian Emeis 《Applied microbiology and biotechnology》1993,39(4-5):574-576
Several different bacteria and fungi capable of degrading yeast cell walls were isolated in the course of a screening programme. One Streptomyces and one Acremonium strain were found to degrade yeast cell walls extremely well. Both isolates produced enzymes in liquid culture that could be used for protoplasting of Sporobolomyces salmonicolor (DSM 70851) and Rhodotorula rubra (DSM 70403). This fact is quite remarkable as, so far, S. salmonicolor could not be protoplasted by commercially available enzymes.
Correspondence to: W. Kaul 相似文献
53.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L11045 (human LMP7) and L11145 (mouse Lmp-7). 相似文献
54.
55.
The human gene encoding cytokeratin 20 and its expression during fetal development and in gastrointestinal carcinomas 总被引:24,自引:0,他引:24
56.
Uwe Karsten Gisela Papsdorf Annedore Pauly Borivoj Vojtesek Roland Moll E. Birgitte Lane Henrik Clausen Peter Stosiek Michael Kasper 《Differentiation; research in biological diversity》1993,54(1):55-66
Abstract. Normal (non-transformed) human mammary epithelial cell lines derived from reduction mammoplasties were analyzed by immunocytochemistry with more than 80 monoclonal antibodies (mAbs) and other specific reagents to tissue-specific and developmentally regulated antigens at different passage levels. A subpopulation of poorly differentiated, proliferating epithelial cells, corresponding to the 'selected' cell type of late passages, is shown to be characterized by a new marker, the histo-blood group antigen H type 2, probably carried on a membrane-bound glycolipid. These cells also express a number of other onco-developmental carbohydrate antigens [Ley , Lex , sialosyl-Lea , precursor of Thomsen Friedenreich antigen (Tn ), but not Thomsen-Friedenreich antigen and sialosyl-Tn ]. Their cytokeratin (CK) phenotype, as assessed by reactivity with monospecific mAbs and two-dimensional gel electrophoresis, is CK 5, 6, 14 and 17, with CK 19 being consistently absent, and varying minor amounts of CK 7, 8 and 18, as well as 15 and 16. The reactivity of these cells with a panel of 11 mAbs specific for CK 18 varies considerably even after cloning, indicating heterogeneity of epitope expression or accessibility. Our data strongly suggest that the H type 2+ cells develop from the basal cell layer of the mammary gland. 相似文献
57.
58.
Summary The spatial distribution and species composition of high-Antarctic ichthyonekton was investigated during the EPOS 3 cruise by RV Polarstern in the eastern Weddell Sea during January–February 1989. A multiple rectangular midwater trawl was used to collect samples from the surface to near the sea floor at 11 stations along a 245 kra transect off Halley Bay. Early larval stages of 18 species, representing about 24% of the known Weddell Sea ichthyofauna, were present in the water column. The Antarctic silver-fish, Pleuragramma antarcticum, over-whelmingly dominated the catches comprising 84.5% of the 5022 specimens caught. The abundance of this species markedly increased towards the offshore end of the transect with the highest numbers occurring near the shelf-break front associated with the westerly current of the southern limb of the Weddell Gyre. The increased abundance of P. antarcticum in continental slope waters was attributed to deflection of the East Weddell Coastal Current beyond the shelf/slope break by fringing ice shelves. Most larval and juvenile fish were found in the seasonally warmed upper 0–70 m layer of the Antarctic Surface Water where conditions occurred that appeared to be favourable to both feeding and growth. Cluster analysis indicated that inner-, central-and outer-shelf assemblages were represented and that the species composition was most effectively described by reference to water mass and depth. 相似文献
59.
Crystalline bacterial cell surface layers 总被引:17,自引:2,他引:15
Crystalline arrays of proteinaceous subunits forming surface layers (S-layers) are one of the most commonly observed prokaryotic cell envelope structures. They are ubiquitous amongst Gram-positive and Gram-negative archaeobacteria and eubacteria and, if present, account for the major protein species produced by the cells. S-layers can provide organisms with a selection advantage by providing various functions including protective coats, molecular sieves, ion traps and structures involved in cell surface interactions. S-layers were identified as contributing to virulence when present as a structural component of pathogens. In Gram-negative archaeobacteria they are involved in determining cell shape and cell division. The crystalline arrays reveal a broad-application potential in biotechnology, vaccine development and molecular nanotechnology. 相似文献
60.
Anita Shepherd Danny Awty-Carroll Jason Kam Chris Ashman Elena Magenau Enrico Martani Mislav Kontek Andrea Ferrarini Stefano Amaducci Chris Davey Vanja Jurišić Gert-Jan Petrie Mohamad Al Hassan Isabelle Lamy Iris Lewandowski Emmanuel de Maupeou Jon McCalmont Luisa Trindade Kasper van der Cruijsen Philip van der Pluijm Rebecca Rowe Andrew Lovett Iain Donnison Andreas Kiesel John Clifton-Brown Astley Hastings 《Global Change Biology Bioenergy》2023,15(4):444-461
New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020–2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020–2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7–89.7 Mt year−1 biomass, with potential for 1.2–1.3 EJ year−1 energy and 36.3–40.3 Mt year−1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety. 相似文献