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81.
Sleep and Biological Rhythms - 相似文献
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The occurrence of a new brassinosteroid of (22S,24R)-3β,22-dihydroxy-5α-ergostan-6-one, named cathasterone, was demonstrated by a GC-MS analysis in cultured cells of Catharanthus roseus. Its endogenous level was in the range of 2–4 ng/g fw, similar to those of brassinolide and castasterone. A feeding experiment with a deuterium-labeled substrate revealed that cathasterone was converted to teasterone and typhasterol. This is the first report of the natural occurrence of cathasterone as a brassinosteroid being the biosynthetic precursor of teasterone. 相似文献
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Hiroshi Oshima Umeko Kawaharada Tokuhiko Kasuga Susumu Mitsuhashi 《Microbiology and immunology》1967,11(2):129-132
The phage typing patterns of phage type 52/52A/80/81 staphylococcal strains were changed to type 80/81 and the non-typable group by lysogenization with phages 27 and 146. When a particular strain of Staphylococcus aureus, MS1590 phage type 52/52A/80/81, was lysogenized with phage 146, type 80/81 and the non-typable group strains were produced. According to the comparison of host range of the prophages, it has been concluded that the two strains with different phage typing patterns have different kinds of prophages. 相似文献
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Kenji Yamamoto Hiroshi Yoshikura Noriko Takahashi Ichizo Kobayashi 《Molecular & general genetics : MGG》1988,212(3):393-404
Summary Gene conversion, the non-reciprocal transfer of sequence information between homologous DNA sequences, has been reported in lower eukaryotes, mammals and in Escherichia coli. In an E. coli rec
+ strain, we established a plasmid carrying two different deleted neo genes (neoDL and neoDR) in an inverted orientation and then selected for homologous recombination events that had reconstructed an intact neo
+ gene. We found some plasmids that had apparently experienced intramolecular gene conversion. Further evidence, however, suggests that they are products of multiple rounds of reciprocal crossing-over,apparently involving two plasmid molecules. First, most of the Neo+ clones contained multiple types of Neo+ plasmids, although the frequency of producing the neo
+ clones was low. Second, all the neo
+ clones also contained, as a minority, one particular form of dimer, which can be formed by reciprocal crossing-over between neoDL of one plasmid molecule and neoDR of another plasmid molecule. Third, in reconstruction experiments, we cloned and purified this dimer and transferred it back into the rec
+ cells. The dimer gave rise to clones containing multiple types of neo
+ recombinant monomers, including those apparent gene conversion types, and containing only few molecules of this dimer plasmid. 相似文献
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