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131.
132.
Expression of the B subunit of<Emphasis Type="Italic"> Escherichia coli</Emphasis> heat-labile enterotoxin as a fusion protein in transgenic tomato 总被引:10,自引:0,他引:10
Walmsley AM Alvarez ML Jin Y Kirk DD Lee SM Pinkhasov J Rigano MM Arntzen CJ Mason HS 《Plant cell reports》2003,21(10):1020-1026
Epitopes often require co-delivery with an adjuvant or targeting protein to enable recognition by the immune system. This paper reports the ability of transgenic tomato plants to express a fusion protein consisting of the B subunit of the Escherichia coli heat-labile enterotoxin (LTB) and an immunocontraceptive epitope. The fusion protein was found to assemble into pentamers, as evidenced by its ability to bind to gangliosides, and had an average expression level of 37.8 microg g(-1) in freeze-dried transgenic tissues. Processing of selected transgenic fruit resulted in a 16-fold increase in concentration of the antigen with minimal loss in detectable antigen. The species-specific nature of this epitope was shown by the inability of antibodies raised against non-target species to detect the LTB fusion protein. The immunocontraceptive ability of this vaccine will be tested in future pilot mice studies. 相似文献
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134.
Multiple isoforms of UDP-GalNAc:polypeptide N-acetylgalactosaminyl-
transferase (ppGaNTase) have been cloned and expressed from a variety of
organisms. In general, these isoforms display different patterns of
tissue-specific expression, but exhibit overlapping substrate
specificities, in vitro . A peptide substrate, derived from the sequence of
the V3 loop of the HIV gp120 protein (HIV peptide), has previously been
shown to be glycosylated in vitro exclusively by the ppGaNTase-T3 (Bennett
et al. , 1996). To determine if this isoform- specificity is maintained in
vivo , we have examined the glycosylation of this substrate when it is
expressed as a reporter peptide (rHIV) in a cell background (COS7 cells)
which lacks detectable levels of the ppGaNTase-T3. Glycosylation of rHIV
was greatly increased by coexpression of a recombinant ppGaNTase-T3.
Overexpression of ppGaNTase- T1 yielded only partial glycosylation of the
reporter. We have also determined that the introduction of a proline
residue at the +3 position flanking the potential glycosylation site
eliminated ppGaNTase- T3 selectivity toward rHIV observed both in vivo and
in vitro .
相似文献
135.
MANUEL B. CRESPO ANTONIO DE LA TORRE JOSE L. SOLANAS 《Botanical journal of the Linnean Society. Linnean Society of London》1994,116(2):135-144
Linaria arabiniana sp. nov. is described from coastal sand dunes of a very reduced area in Alicante Province (south-eastern part of the Iberian Peninsula). It is a perennial herb characterized by its 3–4-verticillate leaves, glabrous stems, large violet or rarely yellow flowers, and bicoloured usually flat seeds. Morphological characteristics and taxonomic affinities of this taxon are discussed, as are data on its ecology, phytosociology, and eventual conservation features. 相似文献
136.
Bulbs were obtained on onion plants cultured in vitro. No bulbinghappened under long days with fluorescent light and 3040g l1 sucrose. Bulb formation was mainly dependent eitheron sucrose concentration in the culture medium, or on lightspectral composition. Raising the sucrose concentration from40 to 120 g l1 increased plant basal swelling and stoppedfurther vegetative development. These plants were not dormant.When fluorescent light was enriched in incandescence duringa long day period, bulbs were obtained in two months and underwenta consecutive dormancy. Bulb, dormancy, light spectral quality, photoperiod, R: FR ratio, sugar, tissue culture 相似文献
137.
The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids. 相似文献
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