Multiple reactions for the asymmetric synthesis of unusual amino acids

Unusual amino acids, such as γ-amino butyric acid (GABA) derivatives and hydroxy amino acids, are known to have worthwhile physiological activities on the mammals or are used as chiral building blocks in the chemical synthesis of other compounds. So far, we have been screening microbial enzymes in order to develop novel biocatalysts useful for various kinds of bioproduction process. In the course of the screening, a variety of enzymes were found to catalyze unique reactions acting to amino acids and the related compounds. Therefore, we suitably combined these biocatalysts and chemical reactions to make multiple reaction systems, by which several unusual amino acids were obtained with high steric purity. Optically active dicarboxylic acid monoamides (chiral half amides) such as (R)-3-(4-chlorophenyl)-glutaric acid monoamide [(R)-CGM] are easily converted into corresponding chiral 3-substituted GABA derivatives by a coupling of Hofmann rearrangement. Some chiral 3-substituted GABA derivatives are used as important medicinal drugs. Chiral half amides are available via desymmetric hydrolysis of prochiral cyclic imides. For the reactions, stereoselective imide-hydrolyzing enzymes (imidases) are necessary to obtain chiral half amides effectively. Then we searched microbial imidases for desymmetric hydrolyze of several cyclic imides. As the result of the microbial screening, Burkholderia phytofirmans DSM17436 was found to have the imidase activity hydrolyzing a cyclic imide, 3-(4-chlorophenyl)glutarimide [CGI], into (R)-CGM with 97.5% ee. An imidase of B. phytofirmans was purified through a classical column chromatographic separation method. The identified enzyme, BpIH, has similarity with an allantoinase of Pseudomonas fluorescens and a 5-benzyl-2,4-thiazolidindione-hydrolyzing enzyme of Brevibacterium linens C-1. Consequently, bioconversion of prochiral CGI into (R)-CGM was achieved with a yield of 99% and 99% ee with the recombinant E. coli cells expressing BpIH. Please click Additional Files below to see the full abstract

サイガイ マネジメント ニ イカス トウショ ノ コミュニティ レジリエンス ノ ソウシュツ : フクオカケン セイホウオキジシン デ ヒサイ シタ ゲンカイジマ ノ ジレイ ヨリ

目的：2005年3月に発生した福岡県西方沖地震で甚大な被害を出した玄界島の復興過程を分析し、災害以前、発災時、避難から帰島、帰島後のコミュニティ・レジリエンスを抽出する。方法：事例研究。結果：災害以前は、様々な災害や危機へのコミュニティとしての対処によってコミュニティ・レジリエンスの潜在能力を高めていた。発災時は日常の防災訓練が生かされ、全員が発災までに形成されていた災害に対処する能力を発揮し避難できた。全戸避難から住宅再建・帰島までは、漁協組合長の強力なリーダーシップや「八軒竃」、もやいで培われた共同性が発揮された。住宅再建・全戸帰島後は、住宅再建・帰島によって「ひと段落」「一休み」という気分があり、「（災害体験）の風化」が生じ、コミュニティレジリエンスは低下している。結論：災害サイクルのすべての時期においてコミュニティ・レジリエンスの基盤となるのは、コミュニティ成員の共同性と共通の関心−コミュニティ・アイデンティティである。This study aims to explore the community resilience in Genkaijima Island examining the four phases such as before the Fukuoka Seiho-oki Earthquake occurred in March 2005, at the time of disaster, during the evacuation and returning, and after returning to the island.It is analyzed multidirectionally the recovery process of the earthquake by the literature on Genkaijima Island, interviews and district surveys.Before the earthquake, community resilience was developed by coping with various disasters and crises.When the earthquake hit the island, people could escape to some safety places and then they were evacuated to Fukuoka city, which was the result of the regular disaster drills.The leadership of the president of the fishermen\u27s cooperative association and the one of both "Hachikenkamado" and "Moyai" cultivated by the community cooperation were shown from the time of all houses refuge to the time of returning to the island.Community resilience in Genkaijima Island has been declining in recent years, because people were relieved from difficulties in shelters, and then they gradually began to forget their disaster experience after returning to the island.It is emphasized that common interest and cooperation in community lead community identity and it forms the basis of community resilience in disaster cycle.報告 = repor

Subcutaneous Single Injection Digital Block with Epinephrine

The aim of this study was to investigate the anesthetic effect and risk of epinephrine for subcutaneous single injection digital block. Either 3.0 mL 1.0% Lidocaine or a 3.0 mL 1.0% Lidocaine with (1 : 100,000) epinephrine was injected into the subcutaneous space at the middle point of the palmar digital crease of the 18 middle fingers of 9 healthy volunteers. The SpO2 of the fingers decreased to a maximum of 97. No subjects showed any symptoms of ischemic injury. The time to anesthesia for the fingers was significantly shorter (P < 0.05), and the duration of anesthesia was significantly longer (P < 0.01) for the fingers in the epinephrine group. In conclusion, a subcutaneous single injection digital blocks with 3.0 mL of 1.0% Lidocaine and (1 : 100,000) epinephrine were safe, reducing the time to the onset of anesthesia, while also markedly prolonging the anesthesia

HSP90α plays an important role in piRNA biogenesis and retrotransposon repression in mouse

HSP90, found in all kingdoms of life, is a major chaperone protein regulating many client proteins. We demonstrated that HSP90α, one of two paralogs duplicated in vertebrates, plays an important role in the biogenesis of fetal PIWI-interacting RNAs (piRNA), which act against the transposon activities, in mouse male germ cells. The knockout mutation of Hsp90α resulted in a large reduction in the expression of primary and secondary piRNAs and mislocalization of MIWI2, a PIWI homolog. Whereas the mutation in Fkbp6 encoding a co-chaperone reduced piRNAs of 28–32 nucleotides in length, the Hsp90α mutation reduced piRNAs of 24–32 nucleotides, suggesting the presence of both FKBP6-dependent and -independent actions of HSP90α. Although DNA methylation and mRNA levels of L1 retrotransposon were largely unchanged in the Hsp90α mutant testes, the L1-encoded protein was increased, suggesting the presence of post-transcriptional regulation. This study revealed the specialized function of the HSP90α isofom in the piRNA biogenesis and repression of retrotransposons during the development of male germ cells in mammals

Comparison of cortical activation during Mahjong game play in a video game setting and a real-life setting

The purpose of this study was to compare the hemodynamic changes that occur during Mahjong game play in virtual and real-life settings. Fourteen healthy right-handed men (average age ± standard deviation; 36.7 ± 14.9 years) played: 1) a Mahjong solitaire game on a video console against virtual rivals; 2) a Mahjong game against human opponents without conversation; and 3) a Mahjong game against human opponents with conversation. We measured oxygenated hemoglobin concentration at 44 locations over both hemispheres during Mahjong game play in each setting using near-infrared spectroscopy. The increase in oxygenated hemoglobin concentration at several locations, including Broca’s area, the somatosensory cortex, the somatosensory association cortex, the supramarginal gyrus part of Wernicke’s area, the primary and auditory association cortex, the angular gyrus part of Wernicke’s area, and the associative visual cortex was greater during game play in the real-life settings than during game play in the video game setting. There were no significant differences during game play in real-life settings without and with conversation. Each cortical area correlated with broad or specific areas. The common correlation areas were found at Angular gyrus part of Wernicke’s area of left hemisphere during real-life settings without and with conversation, but not during game play in a video game setting. These results suggest that the brain responds differently to game play in real world and virtual world settings, and indicate that comparison of games played in the virtual world and the real world may be an effective model to enhance understanding of the effects of video game on the brain.ArticleBiochemistry & Analytical Biochemistry.4(2):164(2015)journal articl

A three-component monooxygenase from Rhodococcus wratislaviensis may expand industrial applications of bacterial enzymes

地球外有機化合物に対する微生物代謝の解明から全く新規な酵素系を発見 --生命分子進化の理解や産業応用に期待--. 京都大学プレスリリース. 2021-01-20.The high-valent iron-oxo species formed in the non-heme diiron enzymes have high oxidative reactivity and catalyze difficult chemical reactions. Although the hydroxylation of inert methyl groups is an industrially promising reaction, utilizing non-heme diiron enzymes as such a biocatalyst has been difficult. Here we show a three-component monooxygenase system for the selective terminal hydroxylation of α-aminoisobutyric acid (Aib) into α-methyl-D-serine. It consists of the hydroxylase component, AibH1H2, and the electron transfer component. Aib hydroxylation is the initial step of Aib catabolism in Rhodococcus wratislaviensis C31-06, which has been fully elucidated through a proteome analysis. The crystal structure analysis revealed that AibH1H2 forms a heterotetramer of two amidohydrolase superfamily proteins, of which AibHm2 is a non-heme diiron protein and functions as a catalytic subunit. The Aib monooxygenase was demonstrated to be a promising biocatalyst that is suitable for bioprocesses in which the inert C–H bond in methyl groups need to be activated

Lasing oscillation in a three-dimensional photonic crystal nanocavity with a complete bandgap

We demonstrate lasing oscillation in a three-dimensional photonic crystal nanocavity. The laser is realized by coupling a cavity mode, which is localized in a complete photonic bandgap and exhibits the highest quality factor of ~38,500, with high-quality semiconductor quantum dots. We show a systematic change in the laser characteristics, including the threshold and the spontaneous emission coupling factor by controlling the crystal size, which consequently changes the strength of photon confinement in the third dimension. This opens up many interesting possibilities for realizing future ultimate light sources and three-dimensional integrated photonic circuits and for more fundamental studies of physics in the field of cavity quantum electrodynamics.Comment: 14 pages, 4 figure

Qualitative investigation of the factors that generate ambivalent feelings in women who give birth after receiving negative results from non-invasive prenatal testing

Background: Women who receive negative results from non-invasive prenatal genetic testing (NIPT) may find that they later have mixed or ambivalent feelings, for example, feelings of accepting NIPT and regretting undergoing the test. This study aimed to investigate the factors generating ambivalent feelings among women who gave birth after having received negative results from NIPT. Methods: A questionnaire was sent to women who received a negative NIPT result, and a contents analysis was conducted focusing on ambivalent expressions for those 1562 women who responded the questionnaire. The qualitative data gathered from the questionnaire were analyzed using the N-Vivo software package. Results: Environmental factors, genetic counseling-related factors, and increased anticipatory anxiety, affected the feeling of ambivalence among pregnant women. Furthermore, pregnant women desired more information regarding the detailed prognosis for individuals with Down syndrome and living with them and/or termination, assuming the possibility that they were positive. Conclusions: Three major interrelated factors affected the feeling of ambivalence in women. Highlighting and discussing such factors during genetic counseling may resolve some of these ambivalences, thereby enhancing the quality of decisions made by pregnant women