Time-resolved and static resonance Raman spectroscopy of horseradish peroxidase intermediates.
Time-resolved and static resonance Raman spectroscopy of horseradish peroxidase intermediates.
复制标题
辣根过氧化物酶中间体的时间分辨和静态共振拉曼光谱。
DOI：
10.1021/bi00409a032
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发表时间：
1988
期刊：
影响因子：
2.9
通讯作者：
Babcock,GT
中科院分区：
文献类型：
--
作者：
Oertling,WA;Babcock,GT
Department of Chemistry，Michigan州立大学，EastLansing，Michigan 48824-1322接收日期：1987年11月5日;修订日期：1987年12月28日摘要：通过使用350-450-nm区域中的脉冲和连续波激光照射，我们表征了辣根过氧化物酶（HRP）化合物I和II以及铁卟啉-阳离子自由基模型化合物的拉曼散射。对于化合物II，我们支持以下建议[Temer，J.，Sitter，A. J.，和雷切克角，加-地M.（1985）Biochim. Biophys. Acta 828，73-80; Proniewicz，LM，Bajdor，K.，& Nakamoto，K.（1986）J.Phys.Chem.90，1760-1766]，Fe IV = 0振动的共振增强通过电荷转移态进行。我们的激发轮廓数据将该状态定位在~ 400 nm处。化合物I在中性pH下通过将静息酶与过氧化氢快速混合来制备。每个样品等分试样由单个10 ns激光脉冲激发，以产生拉曼光谱;拉曼测量后的光谱学证实HRP-I是测量时间范围内的主要产物。然而，这种物质的拉曼光谱不是我们从金属卟啉-阳离子自由基观察到的特征[Oertling，WA，Salehi，A.，Chung，Y.，Leroi，GE，Chang，C. K.，& Babcock，G. T.（1987）J.Phys.Chem.91，5887-5898]，包括本文报道的铁卟啉阳离子自由基。相反，HRP-I在中性pH下记录的光谱表明氧代铁基血红素与HRP-II在高pH下具有相同的几何和电子结构。两种物质之间的相似性延伸到Fe= 0伸缩振动，我们在瞬态物质中观察到该振动的频率（791 cm-1）和强度为高pH非氢键形式的典型强度
Department of Chemistry, Michigan State University, EastLansing, Michigan 48824-1322 Received November 5, 1987; Revised Manuscript Received December 28, 1987 abstract: By using pulsed and continuous wave laser irradiation in the 350-450-nm region, we have characterized Raman scattering from horseradish peroxidase (HRP) compounds I and II and from iron porphyrin-cation radical model compounds. For compound II we support the suggestion [Temer, J., Sitter, A. J., & Reczek, C. M.(1985) Biochim. Biophys. Acta 828, 73-80; Proniewicz, LM, Bajdor, K., & Nakamoto, K.(1986) J. Phys. Chem. 90, 1760-1766] that resonance enhancement of the FeIV= 0 vibration proceeds by way of a charge-transfer state. Our excitation profile datalocate this state at~ 400 nm. Compound I was prepared at neutralpH by rapidmixing of the resting enzyme with hydrogen peroxide. Each sample aliquot was excited by a single, 10-ns laser pulse to generate the Raman spectrum; optical spectroscopy following the Raman measurement confirmedthat HRP-I was the principal product during the time scale of the measurement. The Raman spectrum of this species, however, is not characteristic of that which we observe from metalloporphyrin-cation radicals [Oertling, WA, Salehi, A., Chung, Y., Leroi, GE, Chang, C. K., & Babcock, G. T.(1987) J. Phys. Chem. 91, 5887-5898], including the iron porphyrin cation radicals reported here. Instead, the spectrum recorded for HRP-I at neutral pH is suggestive of an oxoferryl heme with the same geometric and electronic structure as that of HRP-II at high pH. The similarity between the two species extends to the Fe= 0 stretching vibration, which we observe in the transient species at a frequency (791 cm-1) and with an intensity typical of the highpH, non-hydrogen-bonded form