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Ivy Grace Umadhay Pait Shigeru Kitani Farah Wahidah Roslan Dana Ulanova Masayoshi Arai Haruo Ikeda Takuya Nihira 《Journal of industrial microbiology & biotechnology》2018,45(2):77-87
The genome of streptomycetes has the ability to produce many novel and potentially useful bioactive compounds, but most of which are not produced under standard laboratory cultivation conditions and are referred to as silent/cryptic secondary metabolites. Streptomyces lavendulae FRI-5 produces several types of bioactive compounds. However, this strain may also have the potential to biosynthesize more useful secondary metabolites. Here, we activated a silent biosynthetic gene cluster of an uncharacterized compound from S. lavendulae FRI-5 using heterologous expression. The engineered strain carrying the silent gene cluster produced compound 5, which was undetectable in the culture broth of S. lavendulae FRI-5. Using various spectroscopic analyses, we elucidated the chemical structure of compound 5 (named lavendiol) as a new diol-containing polyketide. The proposed assembly line of lavendiol shows a unique biosynthetic mechanism for polyketide compounds. The results of this study suggest the possibility of discovering more silent useful compounds from streptomycetes by genome mining and heterologous expression. 相似文献
165.
Tazro Ohta Takeshi Kawashima Natsuko O. Shinozaki Akito Dobashi Satoshi Hiraoka Tatsuhiko Hoshino Keiichi Kanno Takafumi Kataoka Shuichi Kawashima Motomu Matsui Wataru Nemoto Suguru Nishijima Natsuki Suganuma Haruo Suzuki Y-h. Taguchi Yoichi Takenaka Yosuke Tanigawa Momoka Tsuneyoshi Kazutoshi Yoshitake Yukuto Sato Riu Yamashita Kazuharu Arakawa Wataru Iwasaki 《Journal of plant research》2018,131(4):709-717
Recent studies have shown that environmental DNA is found almost everywhere. Flower petal surfaces are an attractive tissue to use for investigation of the dispersal of environmental DNA in nature as they are isolated from the external environment until the bud opens and only then can the petal surface accumulate environmental DNA. Here, we performed a crowdsourced experiment, the “Ohanami Project”, to obtain environmental DNA samples from petal surfaces of Cerasus?×?yedoensis ‘Somei-yoshino’ across the Japanese archipelago during spring 2015. C. × yedoensis is the most popular garden cherry species in Japan and clones of this cultivar bloom simultaneously every spring. Data collection spanned almost every prefecture and totaled 577 DNA samples from 149 collaborators. Preliminary amplicon-sequencing analysis showed the rapid attachment of environmental DNA onto the petal surfaces. Notably, we found DNA of other common plant species in samples obtained from a wide distribution; this DNA likely originated from the pollen of the Japanese cedar. Our analysis supports our belief that petal surfaces after blossoming are a promising target to reveal the dynamics of environmental DNA in nature. The success of our experiment also shows that crowdsourced environmental DNA analyses have considerable value in ecological studies. 相似文献
166.
Eisuke Sato Maho Morita Haruo Ogawa Masato Iwatsuki Rei Hokari Aki Ishiyama Satoshi Ōmura Arihiro Iwasaki Kiyotake Suenaga 《Bioorganic & medicinal chemistry letters》2018,28(3):298-301
Biselyngbyaside, an 18-membered macrolide glycoside from marine cyanobacteria, and its derivatives are known to be sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) inhibitors. Recently, a SERCA orthologue of the malaria parasite, PfATP6, has attracted attention as a malarial drug target. To provide a novel drug lead, we designed new synthetic analogs of biselyngbyolide B, the aglycone of biselyngbyaside, based on the co-crystal structure of SERCA with biselyngbyolide B, and synthesized them using the established synthetic route for biselyngbyolide B. Their biological activities against malarial parasites were evaluated. 相似文献
167.
Shogo Nakamura Haruo Ogihara Kinue Jinbo Midori Tateishi Tetsuo Takahashi Kenjiro Yoshimura Mamoru Kubota Masakatsu Watanabe Soichi Nakamura 《Phycological Research》2001,49(2):115-121
We have isolated a new Chlamydomonas reinhardtii Dangeard (Chlamydomonadales, Chlorophyceae) mutant with from one up to more than four eyespots cell?1. It was designated mes (multiple eyespots)‐10 A wild‐type cell has a single eyespot, located under the chloroplast envelope, at a certain position near the cell's equator where the chloroplast envelope is in contact with the cell membrane. The eyespot(s) in mes‐10, however, are located at various positions on its chloroplast. The mes‐10 cells displayed negative phototaxis to 480–500 nm light. This behavior differed from that of a similar mutant, ptx4, which has been shown to have multiple eyespots and display no phototaxis (Pazour et al., J. Cell Biol. 1995; 131 : 427–40). Mes‐10 may retain a functional photoreceptor and a photosignal transduction system independently of its multiple eyespots. This mutant should be useful for studying how C. reinhardtii responds to light signals, as well as how eyespots are formed in the cell. 相似文献
168.
Shunsuke Sato Kazuhide Koike Haruo Inoue Osamu Ishitani 《Photochemical & photobiological sciences》2007,6(4):454-461
We report the most efficient homogeneous photocatalyst yet for CO(2) reduction using a wide range of visible-light wavelength. We synthesized new Ru(II)-Re(I) binuclear complexes with 1,3-bis(4'-methyl-[2,2']bipyridinyl-4-yl)-propan-2-ol (bpyC3bpy) as a bridge ligand, specifically [Ru-ReP(OEt)(3)](3+) and [Ru-Repy](3+) where a P(OEt)(3) or pyridine ligand coordinates on the Re site. Their photocatalytic activities were compared with [Ru-ReCl](2+), which has a Cl(-) ligand on the Re site and has recently been reported as a much better photocatalyst (Phi = 0.12, TN(CO) = 160) than a 1:1 mixed system of the corresponding Ru(II) and Re(I) mononuclear complexes. The best photocatalyst was [Ru-ReP(OEt)(3)](3+), for which Phi = 0.21 and TN(CO) = 232. A mechanistic study clearly showed that [Ru-ReP(OEt)(3)](3+) is rapidly converted into the solvento complex [Ru-ReSol](3+), (Sol = DMF or TEOA) which is the actual photocatalyst. Although similar rapid ligand substitution occurs with other supramolecules, the pyridine and Cl(-) anions accelerate the decomposition of the supramolecular photocatalysts. 相似文献
169.
Thirteen species in four genera of mites of the family Macrochelidae phoretic on dung beetles were collected in the eastern part of the Lesser Sunda Islands, Indonesia, providing the first record of the family for that area. Of these, two species, Macrocheles entetiensis Hartini and Takaku, sp. nov. and Macrocheles sumbaensis Hartini and Takaku, sp. nov., are new to science. The remaining 11 species are Glyptholaspis fimicola, Holostaspella bifoliata, Macrocheles baliensis, Macrocheles sp. aff. glaber, M. hallidayi, M. kraepelini, M. krantzi, M. limue, M. merdarius, M. oigru and Neopodocinum sinicum. 相似文献
170.
Haruo Ito Shin-ichi Mitsuhashi Goichi Momose 《Prostaglandins & other lipid mediators》1973,3(3):359-365
P.S.P. excretion in 15 minutes was increased by PGA2 given intravenously in as small a dose as 0.4 μg/min., and the effect was more prominent in case of lower P.S.P. excretion. This finding is not only of significance as to the physiology of the kidney but highly suggestive with regard to the clinical use of prostaglandin. 相似文献