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1.
A consensus linkage map of barley   总被引:5,自引:0,他引:5  
A consensus linkage map of the barley genome was constructed. The map is based on six doubled haploid and one F2 population. The mapping data for three of the doubled haploid populations was obtained via the GrainGenes database. To allow merger of the maps, only RFLP markers that produce a single scorable band were included. Although this reduced the available markers by about half, the resultant map contains a total of 587 markers including 87 of known function. As expected, gene order was highly conserved between maps and all but two discrepancies were found in closely linked markers and are likely to result from the small population sizes used for some maps. The consensus map allows the rapid localisation of markers between published maps and should facilitate the selection of markers for high-density mapping in defined regions.  相似文献   
2.
Aplanospores ofHaematococcus pluvialis MUR 145 contained 0.7% carotenoids (dry wt. basis) consisting of β,β-carotene (5% of total carotenoid), echinenone (4%), canthaxanthin (4%), (3S,3′S)-astaxanthin diester (34%), (3S,3′S)-astaxanthin monoester (46%), (3S,3′S)-astaxanthin (1%) and (3R,3′R,6′R)-lutein (6%). The astaxanthin esters were examined by TLC and HPLC and VIS,1H NMR and mass spectra recorded. Their chirality was determined by the camphanate method (Vecchi & Müller, 1979) after anaerobic hydrolysis. The tough cell wall of the aplanospores required enzymatic treatment prior to pigment extraction. The potential use of this microalga as a feed ingredient in aquaculture is discussed briefly.  相似文献   
3.
Sani MA  Gehman JD  Separovic F 《FEBS letters》2011,585(5):749-754
While neuronal membranes are proposed to be the primary target of amyloid plaques, the effect of phospholipids on fibril formation kinetics and morphology has not yet been resolved. We report that interaction of various compositions with neuronal mimics promoted different processes of fibril formation: negatively charged surfaces increased the lag time and elongation rate in thioflavin T assays, while brain total lipid extract had an opposite effect compared to that in the absence of lipid. Electron microscopy showed thin and elongated fibrils when the peptide was incubated with anionic lipids, while neutral surfaces promoted coarse and small fibrils. Circular dichroism and thioflavin T assays confirmed an initially unstructured peptide, and measured its transition to an aggregated beta-sheet conformation.  相似文献   
4.
5.
  总被引:4,自引:0,他引:4  
We have determined the nucleotide sequence of a 6.3-kb BamHI fragment of the chromosome of Vibrio cholerae 569B that includes the sequence of the mannose-fucose-resistant hemagglutinin reported previously (V.L. Franzon, A. Barker, and P. A. Manning, Infect. Immun. 61:3032-3037, 1993). This region contains nine copies of a 124-bp direct repeat, here named VCR, of imperfect dyad symmetry, that are shown by Southern hybridization to occur at least 60 to 100 times in the V. cholerae O1 chromosome. Large-scale chromosomal mapping suggests that the repeats are confined to about 10% of the chromosome. Related sequences are also found in non-O1 V. cholerae but not in other members of the family Vibrionaceae. However, VCR is unrelated to other previously described repetitive sequences.  相似文献   
6.
Applied Psychophysiology and Biofeedback - Biofeedback (BF) training has been utilized with performers for years. Previous literature highlights the effectiveness of multi-week intervention...  相似文献   
7.
Twenty juvenile northern elephant seals (Mirounga angustirostris) that died between 1998 and 2004 had ulcers on the tongue, palatine mucosa, and/or tonsils. Histologic examination of the lesions revealed cytoplasmic swelling, nuclear pyknosis, and eosinophilic to amphophilic intranuclear inclusions bodies suggestive of herpesviral infection. Electron microscopic examination and polymerase chain reaction analysis confirmed the presence of a herpesvirus. Subsequent DNA sequencing identified this to be a new gammaherpesvirus that was similar to Porcine lymphotropic virus 2, Alcephaline herpesvirus 1 (malignant catarrhal fever virus from wildebeest), and Chlorocebus rhadinovirus 1 from African green monkeys. Identical herpesviral DNA was also detected in blood and mucosal swabs collected from five healthy elephant seal pups.  相似文献   
8.
The Escherichia coli MsbA protein is a 65-kDa member of the ATP-binding cassette superfamily. It is thought to function as an ATP-dependent lipid translocase that transports lipid A from the inner to the outer leaflet of the cytoplasmic membrane. MsbA with high ATPase activity was isolated and found to be homodimeric in detergent solution. The protein ATPase activity was inhibited by vanadate and showed variable patterns of stimulation and inhibition by lipid A and other compounds. The intrinsic tryptophan fluorescence of the protein was characterized, and dynamic quenching using acrylamide showed that a conformational change took place on binding of lipid A. Fluorescence quenching was used to characterize the interactions of MsbA with nucleotides and various putative substrates, including lipids, lipid-like compounds, and drugs. MsbA had an apparent binding affinity for ATP of approximately 2 mm and also bound nonhydrolyzable ATP analogs and fluorescent ATP derivatives. The putative substrate lipid A interacted with the protein with an affinity of 6.4 microm. Drugs that are known to be substrates for ABC multidrug transporters also interacted with MsbA with affinities in the range 0.25-50 microm. This study represents the first use of fluorescence approaches to estimate MsbA binding affinities for nucleotides and putative transport substrates.  相似文献   
9.
A comprehensive understanding of ROS (reactive oxygen species)-dependent cellular interaction requires the previously unmet ability to simultaneously monitor the intra- and extra-cellular environments. The present review assesses the potential of novel electrochemical and fluorescent-based nanosensor approaches to address the limitations of existing techniques for ROS analysis. Data generated by these new approaches have already contributed significantly to current understanding of the roles that these species play in various in vitro scenarios. However, integration of these novel approaches has the potential to offer, for the first time, the unparalleled ability to measure simultaneously and in real-time ROS flux in both the intra- and extra-cellular environments.  相似文献   
10.
Dual polarisation interferometry is an analytical technique that allows the simultaneous determination of thickness, density and mass of a biological layer on a sensing waveguide surface in real time. We evaluated, for the first time, the ability of this technique to characterise the covalent immobilisation of single stranded probe DNA and the selective detection of target DNA hybridisation on a silanised support. Two immobilisation strategies have been evaluated: direct attachment of the probe molecule and a more complex chemistry employing a 1,2 homobifunctional crosslinker molecule. With this technique we demonstrate it was possible to determine probe orientation and measure probe coverage at different stages of the immobilisation process in real time and in a single experiment. In addition, by measuring simultaneously changes in thickness and density of the probe layer upon hybridisation of target DNA, it was possible to directly elucidate the impact that probe mobility had on hybridisation efficiency. Direct covalent attachment of an amine modified 19 mer resulted in a thickness change of 0.68 nm that was consistent with multipoint attachment of the probe molecule to the surface. Blocking with BSA formed a dense layer of protein molecules that absorbed between the probe molecules on the surface. The observed hybridisation efficiency to target DNA was approximately 35%. No further significant reorientation of the probe molecule occurred upon hybridisation. The initial thickness of the probe layer upon attachment to the crosslinker molecule was 0.5 nm. Significant reorientation of the probe molecule surface normal occurred upon hybridisation to target DNA. This indicated that the probe molecule had greater mobility to hybridise to target DNA. The observed hybridisation efficiency for target DNA was approximately 85%. The results show that a probe molecule attached to the surface via a crosslinker group is better able to hybridise to target DNA due to its greater mobility.  相似文献   
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