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131.
Shigeru Kitayama Takashi Karasawa Akira Matsuyama 《Bioscience, biotechnology, and biochemistry》2013,77(4):628-630
The conversion of prochaetoglobosins as plausible precursors into mycotoxin chaetoglobosin A (1) in a cell-free system of Chaetomium subaffine was unsuccessful. However, reductase activity of the 20-keto-analogues (1), and prochaetoglobosins II (5) and III (6) were found in a microsomal fraction of this fungi. Two new metabolites of chaetoglobosins, named chaetoglobosin Fex (2) and 20-dihydro-chaetoglobosin A (3), were also isolated from the same micro-organisms. Their structures were elucidated by spectroscopic data and chemical transformation. 相似文献
132.
Hideoki Tanaka Hidekatsu Maeda Hideo Suzuki Akira Kamibayashi Kenzo Tonomura 《Bioscience, biotechnology, and biochemistry》2013,77(6):1429-1438
A photosynthetic bacterium, which can grow photosynthetically on benzoate, was isolated from sewage mud. Various kinds of aromatic compounds including heterocyclic aromatic compounds were photometabolized by the washed cells grown photosynthetically on benzoate with no lag period. Among these, thiophene-2-carboxylate was metabolized most rapidly to its (+)-tetrahydro derivative. The same strain could also grow on succinate under photosynthetic conditions. However, thiophene-2-carboxylate was only photometabolized after a long lag period by the washed cells grown photosynthetically on succinate, and the metabolite was not its (+)-tetrahydro derivative but (+)-3-hydroxytetrahydrothiophene-2-carboxylate. In the presence of chloramphenicol, an inhibitor of protein synthesis, the photometabolism of thiophene-2-carboxylate by the washed cells grown photosynthetically on benzoate was not affected at all, but the photometabolism of the same substrate by the washed cells grown photosynthetically on succinate was completely inhibited. These results indicate that a reduction system of broad substrate specificity for aromatic rings is already present in the benzoate-grown cells but absent in the succinate-grown cells. It seems that such a reduction system for aromatic rings is induced by an aromatic substrate. 相似文献
133.
134.
Calcification process dynamics in coral primary polyps as observed using a calcein incubation method
Yoshikazu Ohno Akira Iguchi Chuya Shinzato Mikako Gushi Mayuri Inoue Atsushi Suzuki Kazuhiko Sakai Takashi Nakamura 《Biochemistry and Biophysics Reports》2017
Calcification processes are largely unknown in scleractinian corals. In this study, live confocal imaging was used to elucidate the spatiotemporal dynamics of the calcification process in aposymbiotic primary polyps of the coral species Acropora digitifera. The fluorophore calcein was used as a calcium deposition marker and a visible indicator of extracellular fluid distribution at the tissue-skeleton interface (subcalicoblastic medium, SCM) in primary polyp tissues. Under continuous incubation in calcein-containing seawater, initial crystallization and skeletal growth were visualized among the calicoblastic cells in live primary polyp tissues. Additionally, the distribution of calcein-stained SCM and contraction movements of the pockets of SCM were captured at intervals of a few minutes. Our experimental system provided several new insights into coral calcification, particularly as a first step in monitoring the relationship between cellular dynamics and calcification in vivo. Our study suggests that coral calcification initiates at intercellular spaces, a finding that may contribute to the general understanding of coral calcification processes. 相似文献
135.
Liu T Yu H Zhang C Lu M Piao Y Ohba M Tang M Yuan X Wei S Wang K Ma A Feng X Qin S Mukai C Tsuji A Jin F 《Applied and environmental microbiology》2012,78(13):4752-4754
A novel rutin-α-L-rhamnosidase hydrolyzing α-L-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the α-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13. 相似文献
136.
137.
138.
Nakazawa Y Sagane Y Kikuchi T Uchino M Nagai T Sato H Toeda K Takano K 《The protein journal》2010,29(8):598-608
We previously isolated Streptomyces racemochromogenes strain 10-3, which produces a phospholipase D (PLD) with high transphosphatidylation activity. Here, we purified and cloned
the PLD (PLD103) from the strain. PLD103 exerted the highest hydrolytic activity at a slightly alkaline pH, which is in contrast
to the majority of known Streptomyces PLDs that have a slightly acidic optimum pH. PLD103 shares only 71–76% amino acid sequence identity with other Streptomyces PLDs that have a slightly acidic optimum pH; thus, the diversity in the primary structure might explain the discrepancy observed
in the optimum pH. The purified PLD displayed high transphosphatidylation activity in the presence of glycerol, l-serine, and 2-aminoethanol hydrochloride with a conversion rate of 82–97% in a simple one-phase system, which was comparable
to the rate of other Streptomyces PLDs in a complicated biphasic system. 相似文献
139.
Mitsue Shibata Satoshi Kikuchi Hiroshi Tanaka Masahiro Sueyoshi Hiroshi Yoshimaru Kaoru Niiyama 《Ecological Research》2009,24(1):1-9
The effects of local population density, sex morph [protogynous (PG) or protandrous (PA)], and individual tree size on the
demographic processes of seed production were investigated in a heterodichogamous maple, Acer mono Maxim. var. Marmoratum (Nichols.) Hara f. dissectum, in a temperate forest of Japan. As the distance from conspecific reproductive adults increased, the percentage of immature
seed fall and empty seeds increased significantly, indicating higher pollination success along with local population density.
Although the difference was not distinct, pollination success was affected by the local population density of the reciprocal
sex morph rather than that of both sex morphs. The trees at higher local population density sites suffered higher seed mortality
due to predation and decay, and tended to produce smaller seeds. Thus, the impacts of local population density operated both
positively and negatively on reproduction. As a factor of individual traits, tree size scarcely affected any demographic processes.
On the other hand, sex morph did affect pollination success. Trees of PG type had lower immature seed fall than those of PA
type, suggesting that the former has higher efficiency of pollen acceptance than the latter. The results on seed demography
presented here partly support previous suggestions that heterodichogamous plants exhibit reciprocal cross-pollination and
gender specialization as reproductive traits. 相似文献
140.
Akira Kubota Fang He Manabu Kawase Gaku Harata Masaru Hiramatsu Hisakazu Iino 《Current microbiology》2011,62(1):71-77
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis
(JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis
patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with
16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented
milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and
quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with
more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that
lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target
for using probiotics in the management of IgE-mediated allergic disorders including JCPsis. 相似文献