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Sequence-sorted redox-switchable hetero[3]rotaxanes

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Organic Chemistry Frontiers 2022年第1期9卷 64-74页

作者： Marius Gaedke Henrik Hupatz Felix Witte Susanne M.Rupf Clara Douglas Hendrik V.Schröder Lukas Fischer Moritz Malischewski Beate Paulus Christoph A.Schalley Institut für Chemie und biochemie der Freien Universität Berlin Arnimallee 2014195 BerlinGermany Institut für Chemie und biochemie der Freien Universität Berlin Arnimallee 2214195 BerlinGermany Institut für Chemie und biochemie der Freien Universität Berlin Fabeckstr.34/3614195 BerlinGermany

From a library of five crown ether macrocycles with different ring sizes and redox-active moieties,such as tetrathiafulvalene(TTF)and naphthalene dimiide(NDI),directional heterocircuit[3]rotaxanes were *** an axle with two binding sites with different steric accessibility,the concept of integrative self-sorting was applied to program the sequence of functional units in heteropseudo[3]*** on binding strength and ring size of the smaller macrocycles,different heteropseudo[3]rotaxane selectivities and stabilities were determined by 2D NMR spectroscopy and tandem mass spectrometry.A heteropseudo[3]rotaxane with rotaxane-like behaviour was isolated chromatographically,displaying electrochemically“frustrated”properties.A robust synthetic procedure was developed allowing the synthesis of four new hetero[3]rotaxanes incorporating specific sequences of functional *** pseudoisomeric rotaxanes which have the naphthalene diimide subunit at two different positions show distinct electrochemical *** calculations suggest that this differences could arise from a folding of the structure,in which the redox-active moieties stack with a stopper *** study presents a blueprint for the construction of hetero[3]rotaxanes with sequential control of the functional units along the track of the axle and paves the way to extend the functionality of mechanically interlocked molecules.

关键词： properties redox Sequence

Coordination of Schwann cell myelination and node formation at the transcriptional level

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Neural Regeneration Research 2022年第6期17卷 1269-1270页

作者： Franziska Fröb Michael Wegner Institut für biochemie Emil-Fischer-ZentrumFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

Formation of the node of Ranvier as a highly coordinated event:Saltatory conduction ensures that information in the vertebrate nervous system is rapidly transmitted over large distances and efficiently processed in complex *** requires the insulation of axonal segments by myelin and the formation of highly structured nodes of Ranvier that are interspersed at regular intervals between successive myelin sheaths and regenerate the action potential as it propagates along the nerve(Rasband and Peles,2021).

关键词： successive insulation conduction

Isotopic labelling experiments and enzymatic preparation of iso-casbenes with casbene synthase from Ricinus communis

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Organic Chemistry Frontiers 2022年第3期9卷 795-801页

作者： Heng Li Jeroen S.Dickschat Kekulé-Institut für Organische Chemie und biochemie Rheinische Friedrich-Wilhelms-Universität BonnGerhard-Domagk-Straße 153121 BonnGermany

Isotopic labelling experiments gave insights into the enzyme mechanism of casbene synthase from Ricinus communis,showing a clear stereochemical course for the cyclisation reaction,in agreement with the reported absolute configuration of *** oligoprenyl diphosphate analogs with shifted double bonds were synthesised and enzymatically converted with casbene synthase to yield casbene isomers.

关键词： enzymatic isomers bonds

The Tip60/Ep400 chromatin remodeling complex impacts basic cellular functions in cranial neural crest-derived tissue during early orofacial development

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International Journal of Oral Science 2023年第2期15卷 241-254页

作者： Sebastian Gehlen-Breitbach Theresa Schmid Franziska Frob Gabriele Rodrian Matthias Weider Michael Wegner Lina Gölz Institut für biochemie Friedrich-Alexander-Universit?t Erlangen-NürnbergErlangenGermanyand Zahnklinik 3-Kieferorthopodie Universitotsklinikum Erlangen und Friedrich-Alexander-Universitot Erlangen-NürnbergErlangenGermany

The cranial neural crest plays a fundamental role in orofacial development and ***,mutations with impact on the cranial neural crest and its development lead to orofacial malformations such as cleft lip and *** a pluripotent and dynamic cell population,the cranial neural crest undergoes vast transcriptional and epigenomic alterations throughout the formation of facial structures pointing to an essential role of factors regulating chromatin state or transcription levels.

关键词： neural functions alterations

Ethylene Controls Autophosphorylation of the Histidine Kinase Domain in Ethylene Receptor ETR1

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Molecular Plant 2008年第2期1卷 380-387页

作者： Jan Voet-van-Vormizeele Georg Groth Heinrich-Heine-Universitat Biochemie der Pflanzen Universitatsstr. 1 40225 Duisseldorf Germany

Perception of the phytohormone ethylene is accomplished by a small family of integral membrane receptors. In Arabidopsis, five ethylene receptor proteins are known, including ethylene resistant I （ETR1）. The hydrophobic aminoterminal domain of these receptors contains the ethylene-binding site while the carboxyl-terminal part consists of a histidine kinase domain and a response regulator domain, which are well known elements found in bacterial two-component signaling. The soluble membrane-extrinsic carboxyl-terminal part of the receptor, which is likely to play an important role in signal transduction, showed intrinsic kinase activity when expressed and purified on its own. However, a correlation between signal input and autokinase activity was not established in these studies, as receptors were missing the trans- membrane amino-terminal sensor domain. Thus, it is still unclear whether autophosphorylation occurs in response to perception of the ethylene signal. Here, we report on autophosphorylation studies of purified full-length ETR1. Autoki- nase activity of the purified receptor is controlled by ethylene or by ethylene agonists like the π-acceptor compound cyanide. In fact, both signal molecules were able to completely turn off the intrinsic kinase activity, Furthermore, the observed inhibition of autophosphorylation in ETR1 by both molecules could be prevented when the ethylene antagonist 1-methyl-cyclopropene （MOP） was applied.

关键词： ethylene pathway phytohormone receptor membrane protein two-component system signaltransduction Arabidopsis thaliana,

New Insight in Ethylene Signaling： Autokinase Activity of ETR1 Modulates the Interaction of Receptors and EIN2

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Molecular Plant 2010年第5期3卷 882-889页

作者： Melanie M.A. Bisson Georg Groth Heinrich-Heine Universitat Dusseldorf Biochemie der Pflanzen Universitatsstr. 1 40225 Dosseldorf Germany

Ethylene insensitive 2 （EIN2）, an integral membrane protein of the ER network, has been identified as the central regulator of the ethylene signaling pathway. Still, the mechanism by which the ethylene signal is transferred from the receptors to EIN2 has not been solved yet. Here, we show that protein phosphorylation is a key mechanism to control the interaction of EIN2 and the receptors. In vivo and in vitro fluorescence studies reveal that the kinase domain of the receptors is essential for the interaction. Cyanide, an ethylene agonist, which is known to reduce auto-phosphorylation of the ethylene receptor ethylene resistant 1 （ETR1） or a mutation in the kinase domain of ETR1 that prevents autophosphorylation （H353A）, increases the affinity of the receptors for EIN2. On the other hand, mimicking permanent auto-phosphorylation of ETR1 as in the mutant H353E releases the EiN2-ETR1 interaction from the control by the plant hormone. Based on our data, we propose a novel model on the integration of EIN2 in the ethylene signaling cascade.

关键词： Membrane biochemistry protein phosphorylation/dephosphorylation receptors signal transduction membrane proteins ethylene protein-protein interaction.

Neuronspezifische　Enolase　（NSE）：　ein　Serummarker　der　klinischen　Progression　für　maligne　metastasierte　Melanome

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Journal of Huazhong University of Science and Technology(Medical Sciences) 1995年第1期15卷 19-25页

作者：郭华北 Abteilung für Klinische biochemie Bengbu Medizinische Institut Bengbu Institut für Klinische biochemie der Universität Bonn Deutschland

Die Serumkonzentration der neuronspezifischen Enolase(NSE)wurde bei 126 Patienten mit malignem Melanom(MM,Stadium Ⅰ/Ⅱ:n=80;Stadium Ⅲ:n=23;Stadium Ⅳ:n=23)radioimmunologisch *** NSEKonzentrationen(Schwellenwert:>12,5μg/L)fanden sich bei 12,5% der Patienten mit MM im Stadium Ⅰ/Ⅱ,13,0% im Stadium Ⅲ und bei 39,1% im Stadium Ⅳ.In der Langzeit-Verlaufskontrolle bei 20 Patienten im Stadium Ⅲ/Ⅳ zeigte die NSESerumkonzentration eine Ubereinstimmung mit der *** 6 Patienten zeigte sich unter der Therapie ein Abfall erhohter NSE-Werte als Zeichen einer *** Ausbleiben eines signifikanten Abfalls oder gar ein Asstieg wies in 86,7%(13/15)der Falle auf eine Tumorprogression *** signifikanter Anstieg von NSE wurde bei 6 Patienten prdfinal *** laβt sich folgern,daβ NSE fur die Primardiagnostik des malignen Melanoms aufgrund der niedrigen Sensitivitatat als Tumormarker ungeeignet ist;jedoch erscheint eine NSE-Bestimmung bei Patienten mit malignem Melanom im Rahmen einer Verlaufskontrolle sinnvoll.

关键词： Malignes Melanom NSE Serum-Tumormarker

Condensation of pyrylium salts with mixed anhydrides:aryl ethers,aryl amines and sterically congested aromatics

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Organic Chemistry Frontiers 2022年第2期9卷 294-298页

作者： Daniel Grabowski Susanne Alef Steven Becker Ute Muller Gregor Schnakenburg Sigurd Hoger aKekulé-Institut für Organische Chemie und biochemie Rheinische Friedrich-Wilhelms-Universität BonnGerhard-Domagk-Str.153121 BonnGermany bInstitut für Anorganische Chemie Universität BonnGerhard-Domagk-Str.153121 BonnGermany

The condensation of easily accessible and widely functionalizable 2,4,6-triaryl pyrylium salts with mixed anhydrides,formed in situ fromα-functionalized sodium acetates and an anhydride solvent,leads in good yields to the corresponding 2,4,6-triaryl benzenes functionalized at their 1-position.4-(Trifluoromethyl)benzoic anhydride has been proven as being the solvent of choice and ortho-disubstituted diphenyl ethers,triphenyl amines and phenyl carbazoles with different functionalizations are *** addition,sterically hindered anthracene diacetate is condensed with two bis-bromophenyl pyrylium salts which leads after intramolecular Yamamoto coupling to *** these,the anthracene core is surrounded by phenylenes and protected from photooxidation,leading to a highly stable blue emitting material.

关键词： material. anhydride salts

腹足纲Helix pomatia β_C-血清蛋白的功能单位d,e和f中一个半胱氨酸—组氨酸之间硫醚桥键的鉴定(英文)

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药物生物技术 2007年第2期14卷 104-109页

作者：蔡皓 Gielens Constant Préaux Gisele 南京中医药大学江苏省海洋药物研究开发中心江苏南京210029 laboratoriumvoor biochemie Katholieke Universiteit te Leuven

对腹足纲软体动物罗曼蜗牛Helix pomatia的氧运输蛋白(βC-血清蛋白)的功能单位d,e和f中的一个半胱氨酸—组氨酸之间的硫醚桥键进行了研究。以该βC—血清蛋白为载体,通过限制性胰蛋白酶水解,产生片段a-c,ef,以及功能单位d,g,和h。以片... 详细信息

对腹足纲软体动物罗曼蜗牛Helix pomatia的氧运输蛋白(βC-血清蛋白)的功能单位d,e和f中的一个半胱氨酸—组氨酸之间的硫醚桥键进行了研究。以该βC—血清蛋白为载体,通过限制性胰蛋白酶水解,产生片段a-c,ef,以及功能单位d,g,和h。以片段ef降解后的产物为研究对象,通过亲合色谱的分离纯化,得到功能单位e和f。通过对羧甲基化功能单位d的胰蛋白酶和链霉蛋白酶水解,得到一个含有硫醚桥键的4肽。同样在吡啶乙基化功能单位e和f的胰蛋白酶水解产物中也分离得到一个含有相同硫醚桥键的小肽。因此一个半胱氨酸—组氨酸之间硫醚桥键的存在似乎是腹足纲软体动物罗曼蜗牛Helix pomatia氧运输蛋白(βC-血清蛋白)功能单位的一个共有的特征。

关键词： βc-血清蛋白反相高效液相色谱氨基酸分析 DABITC-PITC双偶合法紫外吸收光谱法电喷雾质谱法