Functional variations among LOV domains as revealed by FT-IR difference spectroscopy
Functional variations among LOV domains as revealed by FT-IR difference spectroscopy
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DOI：
10.1039/b400976b
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发表时间：
2004-01-01
影响因子：
3.1
通讯作者：
Heberle, J
中科院分区：
文献类型：
--
作者：
Bednarz, T;Losi, A;Heberle, J
采用光诱导红外差光谱法研究了莱茵衣藻的两个LOV结构域LOV 1和LOV 2，并与枯草芽孢杆菌的LOV结构域（YtvA-LOV）进行了比较。结果表明，反应性LOV 1半胱氨酸C57（1）的两种S-H构象暴露于不同氢键强度的环境中。因此，C57的两种旋转异构体构型可能与三重态双指数衰减成LOV 1 -390光产物的事实有关。LOV 1的另外两个半胱氨酸（C32 S和C83 S）的交换不会改变S-H伸缩带，这提供了该带特征仅来自C57的证据。来自莱茵衣藻的LOV 2（C250）和YtvA-LOV（C62）的反应性半胱氨酸均表现出均匀的S-H伸缩振动带，这表明氨基酸侧链的单一构象异构体。最后，FT-IR差异光谱的YtvA从枯草芽孢杆菌包括光吸收LOV结构域和推定的信号STAS（硫酸盐转运蛋白/antisigma因子拮抗剂）结构域，揭示了后者的构象变化后，蓝光激发。
The two LOV domains, LOV1 and LOV2, from Chlamydomonas reinhardtii were investigated by light-induced FT-IR difference spectroscopy and compared to the LOV domain of Bacillus subtilis (YtvA-LOV). It is shown that the two S-H conformations of the reactive LOV1 cysteine C57(1) are exposed to environments of different hydrogen bonding strength. Thus, the two rotamer configurations of C57 might be related to the fact that the triplet state decays biexponentially into the LOV1-390 photoproduct. Exchange of the two other cysteines of LOV1 (C32S and C83S) does not alter the S-H stretching band providing evidence that this band feature arises solely from C57. The reactive cysteine of LOV2 from Chlamydomonas reinhardtii (C250) and of YtvA-LOV (C62) exhibit both a homogenous S-H stretching vibrational band which suggests a single conformer of the amino acid side chain. Finally, the FT-IR difference spectrum of YtvA from Bacillus subtilis comprising the light absorbing LOV domain and the putative signaling STAS (sulfate transporter/antisigma-factor antagonist) domain, reveals conformational changes in the latter after blue-light excitation.