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Amit Rai Michimi Nakamura Hiroki Takahashi Hideyuki Suzuki Kazuki Saito Mami Yamazaki 《Plant cell reports》2016,35(10):2091-2111
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Carbon and nitrogen stable isotope ratios (δ13C and δ15N) have been widely employed in food web analysis. In lotic environments, periphyton is a major primary producer that makes a large contribution to food web production as well as carbon and nitrogen cycling. While the δ13C and δ15N values have many advantages as a natural tracer, the controls over their high spatial and temporal variability in stream periphyton are not well known. Here, we present the global dataset of δ13C and δ15N values of lotic periphyton from 54 published and two unpublished sources, including 978 observations from 148 streams/rivers in 38 regions around the world, from arctic to tropical sites. The 54 published sources were articles recorded during the period of 1994–2016 in 25 academic journals. The two unpublished sources were from the authors’ own data. The dataset showed that δ13C and δ15N values of periphyton ranged from ?47.3 to ?9.3‰ and from ?5.6 to + 22.6‰, respectively. The dataset also includes physicochemical factors (altitude, coordinates, catchment area, width, depth, geology, vegetation, canopy coverage, biome, season, presence of anadromous salmon, temperature, pH, current velocity, and discharge), nutrient data (nitrate and ammonium concentrations), and algal attributes (chlorophyll a concentration, algal species compositions, and carbonates removal) in streams/rivers studied, all of which may help interpret the δ13C and δ15N values of periphyton. The metadata file outlines structure of all the data and with references for data sources, providing a resource for future food web studies in stream and river ecosystems. 相似文献
956.
Akira Uchiyama Takaomi Yaguchi Hiroyuki Nakagawa Kento Sasaki Naoshige Kuwata Hideyuki Matsuura Kosaku Takahashi 《Bioorganic & medicinal chemistry letters》2018,28(6):1020-1023
The isoleucine conjugate of 12-oxo-phytodienoic acid (OPDA-Ile), a new member of the jasmonate family, was recently identified in Arabidopsis thaliana and might be a signaling molecule in plants. However, the biosynthesis and function of OPDA-Ile remains elusive. This study reports an in vitro enzymatic method for synthesizing OPDA-Ile, which is catalyzed by reactions of lipoxygenase (LOX), allene oxide synthase (AOS), and allene oxide cyclase (AOC) using isoleucine conjugates of α -linolenic acid (LA-Ile) as the substrate. A. thaliana fed LA-Ile exhibited a marked increase in the OPDA-Ile concentration. LA-Ile was also detected in A. thaliana. Furthermore, stable isotope labelled LA-Ile was incorporated into OPDA-Ile. Thus, OPDA-Ile is biosynthesized via the cyclization of LA-Ile in A. thaliana. 相似文献
957.
Kaoru Nakamura Takashi Matsumoto Makoto Hirano Hiroshi Kagoshima Toshihide Kuroki Hiroshi Yao Hideyuki Uchimura Tatsuo Nakahara† 《Journal of neurochemistry》1987,48(6):1842-1844
A mass fragmentographic method for the simultaneous quantification of gamma-aminobutyric acid (GABA) and glutamic acid is described. In a convenient one-step reaction, the two amino acids were derivatized with pentafluoropropionic anhydride and pentafluoropropanol. The derivatization products were stable for several days. The technique has been applied to the assay of GABA and Glu in five amygdaloid nuclei of the rat brain. The GABA level was high in the central and medial nuclei, whereas the Glu level was high in the lateral and basal nuclei. The regional distribution of GABA was different from that of Glu within the amygdaloid nuclei. 相似文献
958.
The primary structures of the immunity (Imm) and lysis (Lys) proteins, and the C-terminal 205 amino acid residues of colicin E8 were deduced from nucleotide sequencing of the 1,265 bp ClaI-PvuI DNA fragment of plasmid ColE8-J. The gene order is col-imm-lys confirming previous genetic data. A comparison of the colicin E8 peptide sequence with the available colicin E2-P9 sequence shows an identical receptor-binding domain but 20 amino acid replacements and a clustering of synonymous codon usage in the nuclease-active region. Sequence homology of the two colicins indicates that they are descended from a common ancestral gene and that colicin E8, like colicin E2, may also function as a DNA endonuclease. The native ColE8 imm (resident copy) is 258 bp long and is predicted to encode an acidic protein of 9,604 mol. wt. The six amino acid replacements between the resident imm and the previously reported non-resident copy of the ColE8 imm ([E8 imm]) found in the ribonuclease-producing ColE3-CA38 plasmid offer an explanation for the incomplete protection conferred by [E8 Imm] to exogenously added colicin E8. Except for one nucleotide and amino acid change in the putative signal peptide sequence, the ColE8 lys structure is identical to that present in ColE2-P9 and ColE3-CA38. 相似文献
959.
Yamaguchi Isomaro; Nakazawa Hideyuki; Nakagawa Ryusuke; Suzuki Yoshihito; Kurogochi Shin; Murofushi Noboru; Takahashi Nobutaka; Weiler Elmar W. 《Plant & cell physiology》1990,31(8):1063-1069
Radioimmunoassays and enzyme-linked immunosorbent assays formethyl esters of gibberellins A1, A3, A4, and A7 were establishedusing an antiserum specific for GA1-Me. The antiserum was characterizedby high titer and specificity for such C19-GAs with 3ß-hydroxylgroup as GA1, GA3, GA4 and GA7. Combination of this antiserumand HPLC enabled us to identify and quantify GA, and GA4 fromthe pollen of Zea mays with a high degree of reliability. Similarly,identification and quantification of GA9 and GA20 were alsomade possible by use of an antiserum specific for GA20-Me. Combineduse of immunoassays and GC/MS enabled us to identify nine GAsfrom the pollen and four from the anthers of Zea mays. The identificationof non-13-hydroxylated GAs, such as GA4 and GA9, in additionto 13-hydroxylated GAs from the pollen and the anthers suggeststhat the early-non-hydroxylation pathway, as well as the early-13-hydrox-ylationpathway, operates in the male reproductive organs of Zea mays,and that the organ-specific biosynthesis and/or localizationof GAs in Zea mays is similar to that in Oryza saliva. (Received May 7, 1990; Accepted August 20, 1990) 相似文献
960.
Enzymatic synthesis of γ-glutamyl-l-histidine by γ-glutamyltranspeptidase from Escherichia coli K-12
Hidehiko Kumagai Takashi Echigo Hideyuki Suzuki Tatsurokuro Tochikura 《Letters in applied microbiology》1989,8(4):143-146
γ-Glutamyl- l -histidine was synthesized from l -glutamine and l -histidine by γ-glutamyltranspeptidase (EC 2.3.2.2) from Escherichia coli K-12. The optimum conditions for the production of γ-glutamyl- l -histidine are determined. The yield of γ-glutamyl- l -histidine synthesized under the optimum conditions was 48% with both substrates (41.2 g/l). The product was isolated and then identified by an amino acid analyser, PMR spectrum and secondary ion mass spectrum analyses. 相似文献