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581.
Poly(uridylic acid) (poly[U]) and poly(adenylic acid) (poly[A]) are efficiently cleaved, via phosphodiester linkage hydrolysis, at pH 8, 50 degrees C by use of poly(vinyladenine-co-vinylamine) as catalyst. The catalytic activity of the copolymer surpasses the value of poly(vinylamine), indicating a significant role of the adenine residue in the copolymer for the effective catalysis.  相似文献   
582.
Despite studies of the mechanism underlying the intracellular localization of membrane proteins, the specific mechanisms by which each membrane protein localizes to the endoplasmic reticulum, Golgi apparatus, and plasma membrane in the secretory pathway are unclear. In this study, a discriminant analysis of endoplasmic reticulum, Golgi apparatus and plasma membrane-localized type II membrane proteins was performed using a position-specific scoring matrix derived from the amino acid propensity of the sequences around signal-anchors. The possibility that the sequence around the signal-anchor is a factor for identifying each localization group was evaluated. The discrimination accuracy between the Golgi apparatus and plasma membrane-localized type II membrane proteins was as high as 90%, indicating that, in addition to other factors, the sequence around signal-anchor is an essential component of the selection mechanism for the Golgi and plasma membrane localization. These results may improve the use of membrane proteins for drug delivery and therapeutic applications.  相似文献   
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A partially purified fraction (Component I) which catalyzed the ATP-PPi exchange reaction dependent only on valine and glycine among the five constituent amino acids of gramicidin A was obtained from crude extracts of Bacillus brevis ATCC 8185, which produces both gramicidin A and tyrocidines. This fraction was found to bind valine and glycine as thioesters. The addition of a formylTHFA synthesizing system to Component I brought about the formation of Component I-bound formylvaline and formylvalylglycine.  相似文献   
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We performed whole-genome Illumina resequencing of 198 accessions to examine the genetic diversity and facilitate the use of soybean genetic resources and identified 10 million single nucleotide polymorphisms and 2.8 million small indels. Furthermore, PacBio resequencing of 10 accessions was performed, and a total of 2,033 structure variants were identified. Genetic diversity and structure analysis congregated the 198 accessions into three subgroups (Primitive, World, and Japan) and showed the possibility of a long and relatively isolated history of cultivated soybean in Japan. Additionally, the skewed regional distribution of variants in the genome, such as higher structural variations on the R gene clusters in the Japan group, suggested the possibility of selective sweeps during domestication or breeding. A genome-wide association study identified both known and novel causal variants on the genes controlling the flowering period. Novel candidate causal variants were also found on genes related to the seed coat colour by aligning together with Illumina and PacBio reads. The genomic sequences and variants obtained in this study have immense potential to provide information for soybean breeding and genetic studies that may uncover novel alleles or genes involved in agronomically important traits.  相似文献   
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Journal of Plant Research - The original article has been updated.  相似文献   
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Polymeric nanoparticles (NPs) comprised of hydrophilic poly(γ-glutamic acid) in the main chain and hydrophobic phenylalanine in the side chain (γ-PGA-Phe) are a promising vaccine carrier for various kinds of diseases. However, little is known about the fate of subcutaneously administered γ-PGA-Phe NPs. Therefore, we newly synthesized γ-PGA graft phenylalanine and tyrosine conjugates (γ-PGA-Phe-Tyr), and then γ-PGA-Phe-Tyr NPs were labeled with 125I for monitoring their biodistribution (γ-PGA-Phe-Tyr(125I) NPs). Dynamic light scattering (DLS) measurements showed that γ-PGA-Phe-Tyr(125I) NPs showed 200 nm in diameter and a negative ζ-potential, which was comparable to those of their precursors. γ-scintigraphic images showed that in mice, subcutaneously injected γ-PGA-Phe-Tyr(125I) NPs were mainly observed at the site of injection (SOI), but not other organs 1 h after administration. However, γ-PGA-PheTyr(125I) NPs were almost undetectable at the SOI and other organs at 11 days postinjection. Similar results were observed when γ-PGA-Phe-Tyr(125I) NPs were subcutaneously injected into rats. Furthermore, at 11 days postinjection, 73 ± 3% of the injected dose of γ-PGA-Phe-Tyr(125I) NPs was detected in the feces (14 ± 1%) and urine (59 ± 1%). These results clearly showed that subcutaneously injected γ-PGA-Phe-Tyr(125I) NPs were cleared from the body, and γ-PGA-Phe NPs were safe and effective vaccine carriers.  相似文献   
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