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101.
Many plant proteins, particularly those found in foods and pollen,are known to act as sensitizing agents in humans upon repeatedexposure. Among the cereal flour proteins involved in asthmaticreactions, those members of the  相似文献   
102.
The period (per) locus has received much attention in molecular evolution studies because it is one of the best studied "behavioral genes" and because it offers insight into the evolution of repetitive sequences. We studied most of the coding region of per in Drosophila willistoni and confirmed previously observed patterns of conservation and divergence among distantly related species. Five regions are so highly diverged that they cannot be aligned, whereas a region encompassing the PAS domain is very conserved. Structural and nucleotide polymorphism patterns in the willistoni group are not the same as those observed in previously studied species. We sequenced the region homologous to the highly polymorphic threonine-glycine repeat of D. melanogaster in multiple strains of D. willistoni, as well as in other members of willistoni group, and found an unusual amount of conservation in this region. However, the next nonconserved region downstream in the sequence is quite variable and polymorphic for the number of repeated glycines. The glycine codon usage is significantly different in this glycine repeat as compared to other parts of the gene. We were able to plot the directionality of change in the glycine repeat region onto a phylogeny and find that the addition of glycines is the general trend with the diversification of the willistoni group.   相似文献   
103.
Summary Three -amylase inhibitors, designated Inh. I, II and III have been purified from the 70% ethanol extract of hexaploid wheat (Triticum aestivum L.) and characterized by amino acid analysis, N-terminal amino acid sequencing and enzyme inhibition tests. Inhibitors I and III have identical N-terminal sequences and inhibitory properties to those of the previously described 0.19/0.53 group of dimeric inhibitors. Inhibitor II has an N-terminal sequence which is identical to that of the previously described 0.28 monomeric inhibitor, but differs from it in that in addition to being active against -amylase from Tenebrio molitor, it is also active against mammalian salivary and pancreatic -amylases. Compensating nulli-tetrasomic and ditelosomic lines of wheat cv. Chinese Spring have been analysed by two-dimensional electrophoresis, under conditions in which there is no overlap of the inhibitors with other proteins, and the chromosomal locations of the genes encoding these inhibitors have been established: genes for Inh. I and Inh. III are in the short arms of chromosomes 3B and 3D, respectively, and that for Inh. II in the short arm of chromosome 6D.  相似文献   
104.
A cDNA clone, designated pUP-44, whose longest open reading frame codes for a protein that is homologous to the wheat alpha-amylase inhibitors, has been isolated from a library obtained from developing barley endosperm. The deduced sequence for the mature protein, which is 122 residues long, is preceded by a sequence of 30 residues which has the typical features of a signal peptide. A closely corresponding protein, designated BDAI-1, has been isolated from mature endosperm. BDAI-1 behaves as a dimer and inhibits the alpha-amylase from the insect Tenebrio molitor at concentrations that have no effect on salivary or pancreatic alpha-amylases.  相似文献   
105.
The effectiveness of Agrobacterium radiobacter K84, 0341, and a K84 non-agrocin-producing mutant (K84 Agr-) in biological control of crown gall on rootstocks of stone fruit trees was determined in three experiments. In experiment 1, K84 and 0341 controlled crown gall on plum plants in soil inoculated with two strains of Agrobacterium tumefaciens resistant to agrocin 84. In experiment 2, K84 controlled crown gall on peach plants in soils inoculated with strains of A. tumefaciens sensitive or resistant to agrocin 84 or with a mixture of both. However, the effectiveness of K84 was higher against the sensitive strain than against the resistant strain. There was a residual effect of K84 from one year to another in soil inoculated with the sensitive strains. In experiment 3, K84 and K84 Agr- controlled crown gall on plum and peach plants in soils inoculated with strains of A. tumefaciens sensitive or resistant to agrocin 84. The control afforded by K84 was higher than that provided by K84 Agr- against the sensitive strain but was similar against the resistant strain.  相似文献   
106.
The identification of the conventionally accepted species of Clavulina (Cantharellales, Basidiomycota) in Europe (Clavulina amethystina, Clavulina cinerea, Clavulina cristata, and Clavulina rugosa) is often difficult and many specimens are not straightforwardly assignable to any of those four species, which is why some authors have questioned their identity. In order to assess the status of those species, a morphological examination was combined with the molecular analysis of the ITS region. The same six major clades were obtained in the Bayesian and parsimony phylogenetic analyses, and all six clades were well-supported at least by one of the analyses. Morphological characters, such as the overall branching pattern, the presence and intensity of grey colour, the cristation of the apices, and basidiospore size and shape were to various extents correlated with the phylogenetic signal obtained from the ITS region. The congruence between the molecular analyses and morphology, rather than geographical origin, suggests the existence of several species that can be delimited using a combined phylogenetic and morphological species recognition. The analyses revealed that C. cristata and C. rugosa are well-delimited species. In contrast, more than one taxa could be subsumed under the names C. amethystina and C. cinerea, the taxonomical complexity of which is discussed. The ITS region is proved to be adequate to separate phylogenetic species of Clavulina.  相似文献   
107.
108.
The N-terminal amino acid sequences of two chloroform/methanol soluble globulins from barley and one form wheat are reported. They are homologous with N-terminal sequences previously reported for α-amylase and trypsin inhibitors from cereals and 2 S storage proteins from castor bean and rape. Three albumins were also purified from Aegilops squarrosa and Triticum monococcum. These had N-terminal amino acid sequences most closely related to the α-amylase and trypsin inhibitors. The relationships of this superfamily of seed proteins are discussed.  相似文献   
109.
Physiological functions of mineral macronutrients   总被引:6,自引:0,他引:6  
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110.
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