イソプレン ソクサ オ ユウスル ショクブツ セイブン ノ ex vivo ユウキ ゴウセイ ト ソノ セイリ カッセイ ノ ヒョウカ

Phytyl quinols, namely acyclic tocopherols, are key intermediates of tocopherol biosynthesis, but their biological activities remain unclear. We therefore investigated the structure-activity relationship of phytyl quinols to apply a chemical biosynthesis design for an antiatherosclerosis drug based on isoprenomics. We have achieved the biosynthesis-oriented synthesis of α- and β-phytyl quinol as an unnatural intermediate, other γ- and δ-phytyl quinol as a natural one. All four phytyl quinols showed almost the same moderate inhibitory activity against low-density lipoprotein oxidation instead of their different degree of C-methylation with character different from tocopherols. In vivo toxicities of phytyl quinols against chick embryo chorioallantoic membrane vasculature were hardly observed. We proposed phytyl quinols were possible antioxidants in plants and animals, like vitamin E

イソプレン ソクサ オ ユウスル ショクブツ セイブン ノ ex vivo ユウキ ゴウセイ ト ソノ セイリ カッセイ ノ ヒョウカ

Phytyl quinols, namely acyclic tocopherols, are key intermediates of tocopherol biosynthesis, but their biological activities remain unclear. We therefore investigated the structure-activity relationship of phytyl quinols to apply a chemical biosynthesis design for an antiatherosclerosis drug based on isoprenomics. We have achieved the biosynthesis-oriented synthesis of α- and β-phytyl quinol as an unnatural intermediate, other γ- and δ-phytyl quinol as a natural one. All four phytyl quinols showed almost the same moderate inhibitory activity against low-density lipoprotein oxidation instead of their different degree of C-methylation with character different from tocopherols. In vivo toxicities of phytyl quinols against chick embryo chorioallantoic membrane vasculature were hardly observed. We proposed phytyl quinols were possible antioxidants in plants and animals, like vitamin E

On-surface synthesis and characterization of nitrogen-substituted undecacenes

Heteroatom substitution in acenes allows tailoring of their remarkable electronic properties, expected to include spin-polarization and magnetism for larger members of the acene family. Here, we present a strategy for the on-surface synthesis of three undecacene analogs substituted with four nitrogen atoms on an Au(111) substrate, by employing specifically designed diethano-bridged precursors. A similarly designed precursor is used to synthesize the pristine undecacene molecule. By comparing experimental features of scanning probe microscopy with ab initio simulations, we demonstrate that the ground state of the synthesized tetraazaundecacene has considerable open-shell character on Au(111). Additionally, we demonstrate that the electronegative nitrogen atoms induce a considerable shift in energy level alignment compared to the pristine undecacene, and that the introduction of hydro-aza groups causes local anti-aromaticity in the synthesized compounds. Our work provides access to the precise fabrication of nitrogen-substituted acenes and their analogs, potential building-blocks of organic electronics and spintronics, and a rich playground to explore π-electron correlation

Gene Organization in Rice Revealed by Full-Length cDNA Mapping and Gene Expression Analysis through Microarray

Rice (Oryza sativa L.) is a model organism for the functional genomics of monocotyledonous plants since the genome size is considerably smaller than those of other monocotyledonous plants. Although highly accurate genome sequences of indica and japonica rice are available, additional resources such as full-length complementary DNA (FL-cDNA) sequences are also indispensable for comprehensive analyses of gene structure and function. We cross-referenced 28.5K individual loci in the rice genome defined by mapping of 578K FL-cDNA clones with the 56K loci predicted in the TIGR genome assembly. Based on the annotation status and the presence of corresponding cDNA clones, genes were classified into 23K annotated expressed (AE) genes, 33K annotated non-expressed (ANE) genes, and 5.5K non-annotated expressed (NAE) genes. We developed a 60mer oligo-array for analysis of gene expression from each locus. Analysis of gene structures and expression levels revealed that the general features of gene structure and expression of NAE and ANE genes were considerably different from those of AE genes. The results also suggested that the cloning efficiency of rice FL-cDNA is associated with the transcription activity of the corresponding genetic locus, although other factors may also have an effect. Comparison of the coverage of FL-cDNA among gene families suggested that FL-cDNA from genes encoding rice- or eukaryote-specific domains, and those involved in regulatory functions were difficult to produce in bacterial cells. Collectively, these results indicate that rice genes can be divided into distinct groups based on transcription activity and gene structure, and that the coverage bias of FL-cDNA clones exists due to the incompatibility of certain eukaryotic genes in bacteria