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21.
A cDNA probe for the low density lipoprotein (LDL) receptor gene was used to screen DNA samples from 52 unrelated Finnish patients with the heterozygous form of familial hypercholesterolemia (FH) and 51 healthy controls. Southern blot analysis using the restriction enzyme PvuII revealed an abnormal 11 kb (kilo base-pair) restriction fragment in 16 (31%) of the patients but none of the controls. A more detailed restriction enzyme analysis of the DNA from patients revealed a mutation which apparently is due to an 8 kb deletion extending from intron 15 to exon 18 of the LDL receptor gene. Co-segregation of FH with the mutated gene was demonstrated in three families. These data are consistent with a ‘founder gene effect’ and support the assumption that recombinant DNA methods may have great impact on the diagnostics of FH in genetically homogeneous populations. 相似文献
22.
Sterol composition of a δ5,7-sterol-rich strain ofSaccharomyces cerevisiae during batch growth 总被引:1,自引:0,他引:1
Sterol composition was examined during batch growth on complex media containing ethanol, molasses or glucose as the carbon source. The molasses-grown cells exhibited a balanced sterol composition throughout growth, maintaining the proportion of ergosterol to 24:28-dehydroergosterol equal to 1.4. The negative effect of glucose on sterol synthesis manifested itself by decreasing the accumulation of 24:28-dehydroergosterol and total sterols but not of ergosterol. Using ethanol as the sole carbon source, a large amount of 24:28-dehydroergosterol accumulated, partly at the expense of other sterols. The gradual addition of nitrogen source during growth significantly decreased the accumulation of ergosterol, 24:28-dehydroergosterol and of total sterols. A general scheme of regulation of sterol synthesis in baker's yeast is presented. 相似文献
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In submerged Claviceps cultures the activity of hydroxymethylglutaryl-CoA reductase preceded the increase of alkaloid production and of sterol content. During the first alkaloid phase, cell mevalonate was involved in the biosynthesis of both alkaloids and steroids. In the second production phase, it was predominantly used for alkaloid synthesis. Hydroxymethylglutaryl-CoA reductase appears to be a suitable target for physiological manipulation to increase clavine alkaloid yields. 相似文献
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Data are presented on the aboveground and underground biomass of the speciesMarsilea quadrifolia and on the water regime and soil conditions in a habitat of this species in Central Europe (Czechoslovakia). 相似文献
27.
Heikki O. Laurila Helena Nevalainen Veijo Mäkinen 《Applied microbiology and biotechnology》1985,21(3-4):210-212
Summary Protoplast formation in Curvularia inaequalis was achieved using non-commercial and commercial snail gut enzymes or Trichoderma harzianum enzymes. The cells were grown for enzyme treatment on cellophane sheets or in liquid cultures for varying periods of time. The production of T. harzianum enzymes is discussed. The highest protoplast yields were 2.6x107 protoplasts/ml enzyme solution. Protoplasts were shown to have zero to four nuclei. Protoplast regeneration was succesfully carried out in semisolid agar. 相似文献
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Meria E. Penttilä K. M. Helena Nevalainen Alain Raynal Jonathan K. C. Knowles 《Molecular & general genetics : MGG》1984,194(3):494-499
Summary The possibility of cloning filamentous fungal genes by expression in the yeast Saccharomyces cerevisiae has been studied. A genome bank of Aspergillus niger was made in E. coli using a yeast cosmid shuttle vector and over 10,000 different cosmid clones were individually isolated. Yeast transformants carrying Aspergillus DNA were screened for the expression of the genes for fungal secreted glycoproteins, -galactosidase, -glucosidase, and amyloglucosidase, and for the expression of fungal genes complementing yeast ura3 and leu2 mutations.Of the five Aspergillus genes studied, only one, -glucosidase, was found to be expressed in yeast, and this at a low level. This suggests that there are essential differences between the genes of yeast and filamentous fungi. 相似文献
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