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1.
D A Nickson M W McBride S Zeinali C S Hawes A Petropoulos U W Mueller R G Sutcliffe 《Journal of reproduction and fertility》1991,93(1):149-156
The monoclonal antibody FDO161G reacts with a 43-kDa protein found in human extravillous trophoblast, syncytiotrophoblast, adrenal cortex, interstitial cells of the testis and ovarian follicle cumulus cells. cDNAs for this protein have been isolated from the lambda gt11 library, sequenced, and expressed in COS-7 cells. The protein was identified as 3 beta-hydroxy-5-ene steroid dehydrogenase (HSD). The sequence of the HSD protein raises questions about its association with cell membrane systems. The lack of reactivity of FDO161G with other tissues suggests that HSD has a limited tissue distribution and that other enzymes may exist in peripheral tissues, which can convert delta 5 3-hydroxysteroids to delta 4 3-ketosteroids. 相似文献
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Structural relatedness of lysis proteins from colicinogenic plasmids and icosahedral coliphages 总被引:4,自引:0,他引:4
The host-lysis-inducing functions of phi X174 protein E and MS2 protein L
were recently shown to reside on the N-terminal and C-terminal halves of
the two respective lysis proteins. In the present study it is shown that
the small lysis proteins encoded in various colicinogenic plasmids share
local sequence similarities and certain structural characteristics with the
essential peptides of their coliphage-coded counterparts. Despite their
dissimilar sizes and origins, it is suggested that the colicinogenic lysis
proteins are functionally analogous and evolutionarily related to those of
icosahedral single- stranded DNA and RNA phages.
相似文献
4.
Cecilia PC Soh Alastair SR Donald James Feeney Walter TJ Morgan Winifred M Watkins 《Glycoconjugate journal》1989,6(3):319-332
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity. 相似文献
5.
We screened a total of 1365 pea (Pisum sativum) lines for response to inoculation with Agrobacterium tumefaciens, strain B6, and characterized resistance in one cultivar, Sweet Snap. Sweet Snap seedlings were highly resistant to tumorigenesis under most conditions. Resistance was overcome at inoculum concentrations of greater than 109 bacteria per milliliter. At such high concentrations, very small tumors developed on Sweet Snap in response to four wide-host-range Agrobacterium strains, but tumors on other cultivars were two-to sevenfold larger than those that formed on Sweet Snap. The hypervirulent strain A281 induced larger tumors on Sweet Snap than did other Agrobacterium strains, but tumors on other genotypes were more than 100% larger than those on Sweet Snap. Physiological experiments suggested that tumorigenesis in Sweet Snap is not blocked in early stages of infection, and genetic analysis indicated that inheritance of resistance to crown gall is a quantitative trait. In addition to the observed resistance in Sweet Snap, three `supersusceptible' genotypes, which developed very large tumors, also were identified. 相似文献
6.
The effects of light and temperature on photosynthate partitioning in Antarctic freshwater phytoplankton 总被引:1,自引:0,他引:1
The effects of temperature and radiation flux on the partitioningof photosynthetically fixed carbon into four intracellulai metabolicpools was investigated for natural phytoplankton assemblagesfrom an Antarctic freshwater lake. At ambient temperature, proteinsynthesis was saturated at low photon flux densities (3040µmol m2 s1) and above this flux fixed carbonwas increasingly stored as lipid and polysaccharide. Increasingtemperature raised both the saturated rate of protein synthesisand the photon flux at which saturation occurred. There wasa corresponding decline in the accumulation of reserve products,particularly at low radiation fluxes. The consequences of thispattern of uptake for the phytoplankton is discussed. 相似文献
7.
Batrice Satiat-Jeunemaitre Chris Hawes 《Biology of the cell / under the auspices of the European Cell Biology Organization》1993,79(1):7-15
Summary— The vectorial transport of membrane and macromolecules within the cytoplasm of eukaryotic cells has been the subject of intense investigation over the last decade. In this paper we review some of the recent advances made in our understanding of vesicle transport and the secretory pathway in plant cells. 相似文献
8.
Beatrice Satiat-Jeunemaitre Chris Hawes 《Biology of the cell / under the auspices of the European Cell Biology Organization》1992,74(3):325-328
Summary— The effects of the drug Brefeldin A, shown to block the translocation of proteins between the endoplasmic reticulum and the Golgi apparatus in animal cells, were studied on different plant cell systems. In suspension culture cells and root tissues, the Golgi aparatus was affected by Brefeldin A treatments resulting in distortion and dissociation of the Golgi stacks, coupled with appearance of numerous vesicles in the cytoplasm. This process was reversible. Therefore, Brefeldin A provides a powerful tool with which to study Golgi dynamics and function in plant as well as in animal cells. 相似文献
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