13C-Metabolic Flux Analysis Reveals Effect of Phenol on Central Carbon Metabolism in Escherichia coli

Phenol is an important chemical product that can be used in a wide variety of applications, and it is currently produced from fossil resources. Fermentation production of phenol from renewable biomass resources by microorganisms is highly desirable for sustainable development. However, phenol toxicity hampers phenol production in industrial microorganisms such as Escherichia coli. In the present study, it was revealed that culturing E. coli in the presence of phenol not only decreased growth rate, but also biomass yield. This suggests that phenol affects the carbon flow of the metabolism, but the mechanism is unknown. To investigate the effect of phenol on the flux distribution of central carbon metabolism, 13C-metabolic flux analysis (13C-MFA) was performed on cells grown under different phenol concentrations (0, 0.1, and 0.15%). 13C-MFA revealed that the TCA cycle flux reduced by 25% increased acetate production from acetyl-CoA by 30% in the presence of 0.1% phenol. This trend of flux changes was emphasized at a phenol concentration of 0.15%. Although the expression level of citrate synthase, which catalyzes the first reaction of the TCA cycle, does not change regardless of phenol concentrations, the in vitro enzyme activity assay shows that the reaction was inhibited by phenol. These results suggest that the TCA cycle flux decreased due to phenol inhibition of citrate synthase; therefore, ATP could not be sufficiently produced by respiration, and growth rate decreased. Furthermore, since carbon was lost as acetate due to overflow metabolism, the biomass yield became low in the presence of phenol

テクノロジー ト ソウゾウリョク アンダース ト ヨナス ニオケル ギジュツロン ノ ヒカク

本稿の主題は、ギュンター・アンダース（Günther Anders 1902┉1992）とハンス・ヨナス（Hans Jonas 1903┉1993）の技術論を比較することである。両者は、ともにドイツ出身のユダヤ人であり、第二次世界大戦後に技術を哲学的な考察の対象としたことで知られている。両者の技術論は、テクノロジーの潜在的な危険性を指摘し、その克服の手がかりとして想像力を重視している点で、軌を同じくしている。先行研究において、こうした類似性が強調されるあまり、しばしば両者は同一視される傾向にある。しかし、アンダースによって説明される危機が、人間の諸能力の不調和に存するのに対して、ヨナスによって説明される危機は、科学技術文明における没価値的な存在論に存する。この違いは、想像力に対して期待される機能の相違をももたす。こうした観点から、本稿は、アンダースとヨナスの技術論を比較し、テクノロジーと想像力をめぐる両者の差異を明確化する。それによって、両者の思想をそれぞれ正しく解釈するための前提を準備し、テクノロジーをめぐる諸問題に対する解決策を検討することが、本稿の目的である。The purpose of this paper is to compare the philosophies of technology proposed by Günther Anders and Hans Jonas. According to Anders, technology restricts human imagination by its all too destructive powers, causing imbalances between technology and humanity’s true nature through what he calls a ‘Promethean gap’. He suggests ways to address this gap by intentionally expanding upon the imagination. Jonas finds increasing danger on the process of technological civilization by the accelerative and accumulative growth and development of technology. As a result of this, he opines that technology exerts a serious impact on future generations and the range of its influence/s exceeds the ability of humans to make accurate scientific predictions. Jonas suggests that our foundations should be based on ensuring the freedom of human imagination rather than on scientific demonstrations, and on actively arousing fear in humans to thus avoid catastrophic possibilities in the future. In previous studies, the philosophies of technology by both Anders and Jonas have been equated to each other because of their similar emphasis on the human imagination. However, they are not entirely similar because their interpretations of technology and their meanings of imagination are different from each other; equating the two prevents not only the correct interpretation of each philosophy but also the understanding of human beings’ relationships with technology from various points of view. This paper clearly distinguishes the philosophies of technology put forth by Anders and Jonas and by examining both their works, it prepares a foundation upon which to evaluate their validity As a conclusion, this paper considers solutions to various problems surrounding the technolog

ヨナス ノ セキニン ゲンリ ニ オケル リョウシンロン ニ ツイテ

The concept of this paper is to examine how "conscience" is discussed in Jonas' principle of responsibility. Conscience and responsibility are considered to have a close relationship as philosophical concepts, so it is not surprising that Jonas, who develops an ethics centered on the concept of responsibility, also considers conscience thematically. However, conscience is rarely discussed in Jonas's literature. Therefore, the question of how the concept of conscience is positioned in Jonas's principle of responsibility has hardly been discussed in the previous studies. On the other hand, in Philosophical Investigations and Metaphysical Speculations, a work published late in his life, Jonas sporadically discusses the concept of conscience and attempts to place it in relation to the principle of responsibility. From this point of view, this paper analyzes the structure of Jonas's theory of conscience through a thematic examination of the book, examines a perspective for understanding its inner working, and aims to contribute to a more integrated interpretation of Jonas's principle of responsibility. At first, this paper will first outline the basic structure of Jonas's principle of responsibility, and then examine the concept of conscience as described in Philosophical Investigations and Metaphysical Speculations. Then, this paper will point out that the conscience discussed in the book is a mixture of conscience based on nature and conscience based on reflection and show that Jonas's theory of conscience does not necessarily have a clear logical consistency and is presented in an incomplete theoretical form. Then, in order to clarify Jonas's motivation for his theory of conscience, this paper will refer to Jonas's critique of Heidegger and interpretate Jonas's intentions. Finally, this paper will reconstruct Jonas's theory of conscience in relation to the responsibility principle and discuss its significance and limitations.論文須藤訓任教授　退職記念

Long-Term Effect of Enzyme Replacement Therapy with Fabry Disease

Objective. To determine the effects of enzyme replacement therapy (ERT) on the hearing acuity in patients with Fabry disease. Materials. The study sample comprised 34 ears of 17 affected patients who underwent pure-tone audiometry before and after ERT. Methods. The patients were studied in relation to factors such as changes in hearing, presence of accompanying symptoms, status of renal and cardiac function, age, and gender. Data of pure-tone audiometry obtained before ERT and at the final examination were compared. Results. At the end of the follow-up period, no significant worsening of hearing acuity was noted at the end of the follow-up period. SSNHL was detected in 10 ears of 6 patients. Steroid therapy successfully cured the disease in 9 of the 10 ears. Conclusions. No significant worsening of hearing acuity was noted from the beginning to the end of ERT. The rate of improvement in SSNHL of Fabry disease was excellent in the treated patients. Hearing loss is a factor that causes marked deterioration of the patients’ quality of life, and it is desirable that the hearing acuity of patients be periodically evaluated and prompt treatment of SSNHL be administered, if available