On-resin assembly of a linkerless lanthanide(III)-based luminescence label and its application to the total synthesis of site-specifically labeled mechanosensitive channels.
On-resin assembly of a linkerless lanthanide(III)-based luminescence label and its application to the total synthesis of site-specifically labeled mechanosensitive channels.
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基于无连接镧系元素 (III) 的发光标记的树脂组装及其在位点特异性标记的机械敏感通道的全合成中的应用。
DOI：
10.1021/bc0498828
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Kochendoerfer,GerdG
中科院分区：
文献类型：
--
作者：
Becker,ChristianFW;Clayton,Daniel;Shapovalov,George;Lester,HenryA;Kochendoerfer,GerdG
A synthesis strategy for the on-resin assembly of luminescent lanthanide chelates from commercially available compounds was developed. Advantages of the approach include the absence of spacers between the metal ion and the attachment site, and the compatibility with typical chemical protein synthesis protection schemes. Methoxycoumarin-labeled lysine and tris(tert-butyl)-DOTA were consecutively coupled with high efficiency to a free amino group in otherwise fully protected peptide segments using standard peptide synthesis methods. Addition of stoichiometric amounts of Tb3+to the modified, cleaved, and purified peptides yielded the desired lanthanide chelate. Incorporation of this label into a chemically synthesized, full-length mechanosensitive channel of large conductance (MscL) ofE. coliand subsequent reconstitution into vesicles resulted in a functional mechanosensitive channel of comparable conductance to the wild-type channel. However, this channel required increased suction to gate. Excitation of the antenna molecule methoxycoumarin at 336 nm resulted in an emission spectrum typical for Tb3+and a luminescence lifetime of 0.67 ms. The location of the probe close to the backbone of this protein may provide precise information about conformational changes during channel opening from LRET studies.
