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1.
3 beta,16 beta,19-Trihydroxyandrost-5-en-17-one (12) was synthesized from 5 alpha-bromo-3 beta-acetoxy-6 beta,19-epoxyandrostan-17-one (2) through acetoxylation at C-16 beta of the enol acetate 4 with lead tetraacetate and reductive cleavage of the epoxide ring with zinc dust yielding the 3 beta,16 beta-diacetoxy-19-hydroxy steroid 11, followed by hydrolysis of the acetoxy groups with sulfuric acid. Jones oxidation of compound 11 followed by the acid hydrolysis gave the 19-oxo steroid 15. 5 alpha-Bromo-3 beta-hydroxy-16 beta-acetoxy-6 beta,19-epoxyandrostan-17-one (8), obtained by selective hydrolysis of the 3-formate 5 with ammonium hydroxide, was oxidized with Jones reagent to afford the 3-oxo steroid 16, which was converted into the 19-hydroxy derivative 17 by treatment with zinc dust. 16 beta,19-Dihydroxyandrost-4-ene-3,17-dione (18) and its 19-oxo derivative 21 were obtained from compound 17 through a similar reaction sequence. 相似文献
2.
Stabilization of the phosphorylated form of Bacillus subtilis DegU caused by degU9 mutation 总被引:1,自引:0,他引:1
Abstract A Bacillus subtilis response regulator, DegU9, carrying an amino acid alteration caused by the degU9 (Hy) mutation was partially purified, and phosphorylation and dephosphorylation of the protein was studied. The extent of phosphorylation was not as high as the level attained with wild-type DegU, but the DegU9-phosphate once formed was more stable than the wild-type DegU-phosphate. An in vivo study with a degU9 mutant showed that degS was necessary for the overproduction of exoproteases. These results suggest that phosphorylation is necessary for the mutant DegU9 to exert its effect and that the higher stability of phosphorylated DegU9 is responsible for the overproulation phenotype. 相似文献
3.
Sébastien Lavoué Kouji Nakayama Dean R. Jerry Yusuke Yamanoue Naoki Yagishita Nobuaki Suzuki Mutsumi Nishida Masaki Miya 《Gene》2014
Delineation of the fish family Percichthyidae (Percomorphaceae) has a long and convoluted history, with recent morphological-based studies restricting species members to South American and Australian freshwater and catadromous temperate perches. Four recent nuclear gene-based phylogenetic studies, however, found that the Percichthyidae was not monophyletic and was nested within a newly discovered inter-familial clade of Percomorphaceae, the Centrarchiformes, which comprises the Centrarchidae and 12 other families. Here, we reexamined the systematics of the Percichthyidae and Centrarchiformes based on new mitogenomic information. Our mitogenomic results are globally congruent with the recent nuclear gene-based studies although the overall amount of phylogenetic signal of the mitogenome is lower. They do not support the monophyly of the Percichthyidae, because the catadromous genus Percalates is not exclusively related to the freshwater percichthyids. The Percichthyidae (minus Percalates) and Percalates belong to a larger clade, equivalent to the Centrarchiformes, but their respective sister groups are unresolved. Because all recent analyses recover a monophyletic Centrarchiformes but with substantially different intra-relationships, we performed a simultaneous analysis for a character set combining the mitogenome and 19 nuclear genes previously published, for 22 centrarchiform taxa. This analysis furthermore indicates that the Centrarchiformes are divided into three lineages and the superfamily Cirrhitoidea is monophyletic as well as the temperate and freshwater centrarchiform perch-like fishes. It also clarifies some of the relationships within the freshwater Percichthyidae. 相似文献
4.
Yoshiyuki Sakano Mutsumi Sano Tsuneo Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(12):3391-3398
Maltosyl-α-cyclodextrin (6-α-maltosylcyclomaltohexaose, M-CD) was prepared from maltose and α-cyclodextrin by the reverse action of Bacillus pullulanase, and the action of α-amylases on this dextrin was examined. Among α-amylases tested, Thermoactinomyces vulgaris α-amylase (TVA) and Taka-amylase A (TAA) were found to attack the M-CD. Their action pattern on M-CD was studied. These α-amylases cleaved, first the cyclodextrin ring of M-CD, and the branched octasaccharides formed were immediately degraded to form glucose, branched tetraose, or pentaose, though the action pattern was different for TVA and TAA. In addition, TAA also split M-CD into glucose and glucosyl-α-cyclodextrin. Fission products at various stages of the reaction were separated and analyzed by paper chromatography and high performance liquid chromatography, their structures were analyzed, and the degradation pattern of M-CD was found. 相似文献
5.
6.
Tomoyuki Kosaka Mutsumi Goda Manami Inoue Toshiharu Yakushi Mamoru Yamada 《Bioscience, biotechnology, and biochemistry》2019,83(7):1362-1371
The basic functions of a propionate-oxidizing bacterium Pelotomaculum thermopropionicum flagellum, such as motility and chemotaxis, have not been studied. To investigate its motility, we compared with that of Syntrophobacter fumaroxidans, an aflagellar propionate-oxidizing bacterium, in soft agar medium. P. thermopropionicum cells spread, while S. fumaroxidans cells moved downward slightly, indicating flagellum-dependent motility in P. thermopropionicum SI. The motility of P. thermopropionicum was inhibited by the addition of carbonyl cyanide m-chlorophenyl hydrazone, a proton uncoupler, which is consistent with the fact that stator protein, MotB of P. thermopropionicum, shared sequence homology with proton-type stators. In addition, 5-N-ethyl-N-isopropyl amiloride, an Na+ channel blocker, showed no inhibitory effect on the motility. Furthermore, motAB of P. thermopropionicum complemented the defective swimming ability of Escherichia coli ?motAB. These results suggest that the motility of P. thermopropionicum SI depends on the proton-type flagellar motor. 相似文献
7.
Mutsumi Nakamura Takafumi Nagamine Chisato Harada Kiyoshi Tajima Hiroki Matsui Yoshimi Benno 《Current microbiology》2003,47(1):0071-0074
The objective of this study was to ligate the xylanase gene A (xynA) isolated from Ruminococcus albus 7 into the promoter and signal-peptide region of the lichenase [β-(1,3-1,4)-glucanase] gene of Streptococcus bovis JB1. This fusion gene was inserted into the pSBE11 vector, and the resulting recombinant, plasmid pXA, was used to transform
S. bovis 12-U-1 cells. The transformant, S. bovis 12UXA, secreted the xylanase, which was stable against freeze-thaw treatment and long-time incubation at 37°C. The introduction
of pXA and production of xylanase did not affect cell growth, and the xylanase produced degraded xylan from oat-spelt and
birchwood.
Received: 24 June 2002 / Accepted: 7 October 2002 相似文献
8.
The nasomaxillary epithelial inlay skin graft described by H. D. Gillies in 1923 is one of the historical procedures of the twentieth century. Nowadays, this method has been thoroughly abandoned, and no long-term follow-up has been reported. In the Tokyo Metropolitan Police Hospital, between 1962 and 1983, 51 patients with saddle nose were treated using this procedure and a specially devised outer prosthesis. A follow-up study of these cases was attempted and that of nine cases was carried out. Six of nine patients have been using the outer prosthesis without any serious complications and are satisfied to varying extent. Three patients underwent further surgical treatment using autografts because of serious complications, which included full-thickness skin necrosis, refractory ulcer of the dorsum of nose, and anxiety about the unphysiological communication between the nasal and oral cavities. 相似文献
9.
We determined the complete nucleotide sequence of the mitochondrial genome (except for a portion of the putative control
region) for a deep-sea fish, Gonostoma gracile. The entire mitochondrial genome was purified by gene amplification using long polymerase chain reaction (long PCR), and the
products were subsequently used as templates for PCR with 30 sets of newly designed, fish-universal primers that amplify contiguous,
overlapping segments of the entire genome. Direct sequencing of the PCR products showed that the genome contained the same
37 mitochondrial structural genes as found in other vertebrates (two ribosomal RNA, 22 transfer RNA, and 13 protein-coding
genes), with the order of all rRNA and protein-coding genes, and 19 tRNA genes being identical to that in typical vertebrates.
The gene order of the three tRNAs (tRNAGlu, tRNAThr, and tRNAPro) relative to cytochrome b, however, differed from that determined in other vertebrates. Two steps of tandem duplication of gene regions, each followed
by deletions of genes, can be invoked as mechanisms generating such rearrangements of tRNAs. This is the first example of
tRNA gene rearrangements in a bony fish mitochondrial genome.
Received August 5, 1998; accepted February 19, 1999. 相似文献