LOW TEMPERATURE CHEMISTRY/KINETICS/PHOTOAFFINITY LABELS

低温化学/动力学/光亲和标签

• 批准号: 2177594
• 负责人: MATTHEW S PLATZ
• 金额: $ 10.39万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-07-01 至 1995-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2177594
• 关键词: affinity labeling; azides; chemical reaction; chymotrypsin; electron spin resonance spectroscopy; free radicals; freezing; nitrene; photochemistry

During the current grant period have discovered that the photochemistry of simple aromatic aides are remarkably sensitive to temperature. Photolysis of phenyl azide at room temperature produces dehydroazepine which is relatively unreactive and prone to polymerization to form tar. However, photolysis of phenyl azide in a rigid matrix (RH) at 77K produces triplet phenyl nitrene which at this temperature is indefinitely stable in the dark. However, photolysis of triplet nitrenes results in hydrogen atom abstraction from the matrix (RH) to form radical pair, which when warmed to 100K followed by radical pair collapses to form coupling product. The sequences of photochemical steps at 77K efficiently leads to coupling products such as in high yields. We have exploited this by studying the photochemistry and low temperature EPR spectroscopy of modified chymotrypsins at 77K. In this proposal experiments are outlined which extend the low temperature method to other enzymes and which introduce new non covalently bound photoprobe reagents which are expected to be particularly eficient at 77K.

在目前的赠款期间，发现， 简单芳香族助剂的光化学反应非常敏感， 温度。 叠氮苯的室温光解 产生脱氢吖庚因，其相对不反应， 聚合形成焦油。 然而，苯基叠氮的光解 在刚性基体（RH）中，在77K下产生三重苯基氮宾， 在这个温度下在黑暗中是无限稳定的。 但是，在这方面， 三重态氮烯的光解导致氢原子的夺取 从基质（RH）中形成自由基对，当加热时， 100K，随后自由基对塌缩形成偶联产物。 在77K下的光化学步骤的顺序有效地导致 例如以高产率偶联产物。 我们利用了这一点 通过研究光化学和低温EPR光谱， 修饰的胰凝乳蛋白酶在77K。 在这个实验中， 将低温法推广到其它方法， 引入新的非共价结合的光探针 预计在77K下特别有效的试剂。

项目成果

A laser flash photolysis study of di-, tri- and tetrafluorinated phenylnitrenes; implications for photoaffinity labeling.

二氟化苯氮烯、三氟化苯氮烯和四氟化苯氮烯的激光闪光光解研究；

• DOI: 10.1021/bc00020a011
• 发表时间: 1993
• 期刊: Bioconjugate chemistry
• 影响因子: 4.7
• 作者: Schnapp,KA;Platz,MS
• 通讯作者: Platz,MS

The photochemistry of iodo, methyl and thiomethyl substituted aryl azides in toluene solution and frozen polycrystals.

甲苯溶液和冷冻多晶中碘、甲基和硫甲基取代的芳基叠氮化物的光化学。

• DOI: 10.1111/j.1751-1097.1991.tb02024.x
• 发表时间: 1991
• 期刊: Photochemistry and photobiology
• 影响因子: 3.3
• 作者: Leyva,E;Chang,DH;Platz,MS;Watt,DS;Crocker,PJ;Kawada,K
• 通讯作者: Kawada,K

Exploratory photochemistry of 5-azido-8-alkoxy-substituted psoralens free and bound to DNA.

游离和与 DNA 结合的 5-叠氮基-8-烷氧基取代的补骨脂素的探索性光化学。

• DOI: 10.1111/j.1751-1097.1995.tb09875.x
• 发表时间: 1995
• 期刊: Photochemistry and photobiology
• 影响因子: 3.3
• 作者: Chen,T;Michalak,J;Platz,MS
• 通讯作者: Platz,MS

Synthesis and binding of new polyfluorinated aryl azides to alpha-chymotrypsin. New reagents for photoaffinity labeling.

新型多氟芳基叠氮化物的合成及其与α-胰凝乳蛋白酶的结合。

• DOI: 10.1021/bc00022a002
• 发表时间: 1993
• 期刊: Bioconjugate chemistry
• 影响因子: 4.7
• 作者: Soundararajan,N;Liu,SH;Soundararajan,S;Platz,MS
• 通讯作者: Platz,MS