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81.
82.
Karin Schubert Dieter Reiml Jean-Pierre Accolas Franz Fiedler 《Archives of microbiology》1993,160(3):222-228
The primary structure of the peptidoglycan and the teichoic acids of two coryneform isolates from the surface flora of French cooked cheeses, CNRZ 925 and CNRZ 926, have been determined. In the peptidoglycan, meso-diaminopimelic acid was localized in position three of the peptide subunit. It contained an d-glutamyl-d-aspartyl interpeptide bridge, connecting meso-diaminopimelic acid and d-alanine residues of adjacent peptide subunits. The -carboxyl group of d-glutamic acid in position two of peptide subunits was substituted with glycine amide. The teichoic acid pattern and composition differed between the strains: both contained an erythritol teichoic acid and strain CNRZ 925 also contained an N-acetylglucosaminylphosphate polymer. The erythritol teichoic acids differed in terms of the quality and quantity of substituents, but they both had N,N-diacetyl-2,3-diamino-2,3-dideoxyglucuronic acid in common.Abbreviations DNP
dinitrophenyl
- Ery
erythritol
- Gal
galactose
- GlcN
glucosamine
- GlcNAc
N-acetylglucosamine
- GlcUANAc2
N,N-diacetyl-2,3-diamino-2,3-dideoxyglucuronic acid
- Hex UANAc2
N,N-diacetyl-2,3-diamino-2,3-dideoxyhexuronic
- acid
m-Dpm, meso-diaminopimelic acid
- Mur
muramic acid
- MurNAc
N-acetylmuramic acid 相似文献
83.
Adrian Bogdan Tigu Catalin Sorin Constantinescu Patric Teodorescu David Kegyes Raluca Munteanu Richard Feder Mareike Peters Ioana Pralea Cristina Iuga Diana Cenariu Andra Marcu Alina Tanase Anca Colita Rares Drula Jon Thor Bergthorsson Victor Greiff Delia Dima Cristina Selicean Ioana Rus Mihnea Zdrenghea Diana Gulei Gabriel Ghiaur Ciprian Tomuleasa 《Journal of cellular and molecular medicine》2023,27(19):2864-2875
Acute megakaryoblastic leukaemia (AMkL) is a rare subtype of acute myeloid leukaemia (AML) representing 5% of all reported cases, and frequently diagnosed in children with Down syndrome. Patients diagnosed with AMkL have low overall survival and have poor outcome to treatment, thus novel therapies such as CAR T cell therapy could represent an alternative in treating AMkL. We investigated the effect of a new CAR T cell which targets CD41, a specific surface antigen for M7-AMkL, against an in vitro model for AMkL, DAMI Luc2 cell line. The performed flow cytometry evaluation highlighted a percentage of 93.8% CAR T cells eGFP-positive and a limited acute effect on lowering the target cell population. However, the interaction between effector and target (E:T) cells, at a low ratio, lowered the cell membrane integrity, and reduced the M7-AMkL cell population after 24 h of co-culture, while the cytotoxic effect was not significant in groups with higher E:T ratio. Our findings suggest that the anti-CD41 CAR T cells are efficient for a limited time spawn and the cytotoxic effect is visible in all experimental groups with low E:T ratio. 相似文献
84.
Chromosoma - Topoisomerase IIα (Topo IIα) and the centromere-specific histone H3 variant CENH3 are key proteins involved in chromatin condensation and centromere determination,... 相似文献
85.
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
86.
Invasion of tissue culture cells by diarrhoeagenic strains of Escherichia coli which lack the enteroinvasive inv gene 总被引:2,自引:0,他引:2
Aberra Geyid Jon Fletcher Brehanu A. Gashe Åsa Ljungh 《FEMS immunology and medical microbiology》1996,14(1):15-24
Abstract Invasive Escherichia coli strains of certain serotypes invade by the same mechanism as the Shigella sp. It has been proposed that invasion of epithelial cells by EPEC strains may also occur; this is a previously overlooked property. In the present study E. coli strains isolated from patients with diarrhoea or ulcerative colitis, lacking the inv plasmid mediating classical invasion, but hybridizing with probes for different adhesins, were analyzed for their ability to invade HeLa and Caco-2 cells. The majority of strains invaded Caco-2 cells to a higher extent than HeLa cells. Adhesion to Caco-2 cells was a prerequisite for subsequent invasion of the cells but EAF, eae , EAgg and other known virulence factors were not sufficient to mediate invasion. In 8/9 E. coli strains invasion was enhanced after growth under iron restriction. Growth during anaerobic conditions did not influence subsequent invasion by E. coli strains whereas 6/9 strains had their invasive ability significantly decreased after growth in the presence of 1% glucose. The invasive process was inhibited by mannose but not by lactose, fucose or galactose. Our data indicate that strains of E. coli may invade Caco-2 cells by novel mechanisms which require adhesion to the cells but which differ from those of Salmonella sp., Yersinia sp., Shigella sp. and classical enteroinvasive E. coli . 相似文献
87.
Kathleen P. Anderson Christine B. Kern Scott C. Crable Jon C. Neumann Jerry B. Lingrel 《Transgenic research》1996,5(4):245-255
Our interest in thecis-acting elements that promote the up-regulation of the globin gene has led to a systematic deletion analysis of portions of the globin gene in the context of the HS2 and globin gene using transgenic mice. In constructs that delete the 5 region to only 265 bp, high-level erythroid-specific expression was observed. Further deletion to 122 bp, however, results in significantly reduced expression levels A substitution of a minilocus control region for the single HS2 site was also produced, resulting in increased globin expression over that seen with the HS2 alone. These results are consistent with the presence of an enhancer-like element between –122 and –265. In addition, a construct in which the entire globin gene promoter was replaced by a thymidine kinase promoter was tested. Interestingly, no expression was detected in these transgenic mice. This may indicate the requirement for an erythroid-specific promoter to drive this gene. Finally, the 3 region of the globin gene was deleted in order to examine the effect of a previously defined 3 enhancer region. With deletion of this region, the expression of the human globin gene in transgenic mice is unchanged relative to the parental constructs. 相似文献
88.
Sequential isolation of proteoglycan synthesis mutants by using herpes simplex virus as a selective agent: evidence for a proteoglycan-independent virus entry pathway. 总被引:14,自引:9,他引:5
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A novel mouse L-cell mutant cell line defective in the biosynthesis of glycosaminoglycans was isolated by selection for cells resistant to herpes simplex virus (HSV) infection. These cells, termed sog9, were derived from mutant parental gro2C cells, which are themselves defective in heparan sulfate biosynthesis and 90% resistant to HSV type 1 (HSV-1) infection compared with control L cells (S. Gruenheid, L. Gatzke, H. Meadows, and F. Tufaro, J. Virol. 67:93-100, 1993). In this report, we show that sog9 cells exhibit a 3-order-of-magnitude reduction in susceptibility to HSV-1 compared with control L cells. In steady-state labeling experiments, sog9 cells accumulated almost no [35S]sulfate-labeled or [6-3H]glucosamine-labeled glycosaminoglycans, suggesting that the initiation of glycosaminoglycan assembly was specifically reduced in these cells. Despite these defects, sog9 cells were fully susceptible to vesicular stomatitis virus (VSV) and permissive for both VSV and HSV replication, assembly, and egress. HSV plaques formed in the sog9 monolayers in proportion to the amount of input virus, suggesting the block to infection was in the virus entry pathway. More importantly, HSV-1 infection of sog9 cells was not significantly reduced by soluble heparan sulfate, indicating that infection was glycosaminoglycan independent. Infection was inhibited by soluble gD-1, however, which suggests that glycoprotein gD plays a role in the infection of this cell line. The block to sog9 cell infection by HSV-1 could be eliminated by adding soluble dextran sulfate to the inoculum, which may act by stabilizing the virus at the sog9 cell surface. Thus, sog9 cells provide direct genetic evidence for a proteoglycan-independent entry pathway for HSV-1, and results with these cells suggest that HSV-1 is a useful reagent for the direct selection of novel animal cell mutants defective in the synthesis of cell surface proteoglycans. 相似文献
89.
Ivana Gribaudo M. Asuncion Morte Andrea Schubert 《Plant Cell, Tissue and Organ Culture》1995,42(3):303-303
Corrigendum
Use of gentian violet to differentiate in vitro and ex vitro- formed roots during acclimatization of grapevine 相似文献90.
Homopolymer mutational hot spots mediate herpes simplex virus resistance to acyclovir. 总被引:10,自引:3,他引:7
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J J Sasadeusz F Tufaro S Safrin K Schubert M M Hubinette P K Cheung S L Sacks 《Journal of virology》1997,71(5):3872-3878
In the majority of cases, the mechanism underlying the resistance to acyclovir (ACV) of herpes simplex viruses (HSVs) is thymidine kinase (TK) deficiency. Plaque isolates from eight ACV-resistant (ACVr) clinical isolates from AIDS patients, of which five reactivated, were sequenced to determine the genetic lesion within the tk gene conferring resistance and whether this may have correlated with reactivation potential. Mutations were clustered within two homopolymer nucleotide stretches. Three plaque isolates (1737-14, 90-150-3, and 89-650-5) had insertion mutations within a stretch of 7 guanosines, while two isolates (89-063-1 and 89-353-1) had frameshift mutations within a stretch of 6 cytosines (a deletion and an insertion, respectively). Mutations resulted in premature termination codons, and the predicted 28- and 32-kDa truncated TK products were detected by Western blot analysis of virus-infected cell extracts. The repair of one homopolymer frameshift mutation (in isolate 1737-14) restored TK activity, demonstrating that this mutation is the basis of TK deficiency. Of the five reactivated isolates, four were TK deficient and contained frameshift mutations while the fifth retained TK activity because of its altered-TK or Pol- phenotype. These data demonstrate that the majority of ACVr clinical isolates contain frameshift mutations within two long homopolymer nucleotide stretches which function as hot spots within the HSV tk gene and produce nonfunctional, truncated TK proteins. 相似文献