Lignin peroxidase: resonance Raman spectral evidence for compound II and for a temperature-dependent coordination-state equilibrium in the ferric enzyme.
Lignin peroxidase: resonance Raman spectral evidence for compound II and for a temperature-dependent coordination-state equilibrium in the ferric enzyme.
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木质素过氧化物酶：化合物 II 和三价铁酶中温度依赖性配位态平衡的共振拉曼光谱证据。
DOI：
10.1021/bi00382a028
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发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
Gold,MH
中科院分区：
文献类型：
--
作者：
Andersson,LA;Renganathan,V;Loehr,TM;Gold,MH
俄勒冈研究生中心化学与生物科学系，俄勒冈州比弗顿97006-1999摘要：担子菌黄孢Phanerochaete chrysosporium的木质素过氧化物酶（木质素酶，二芳基丙烷加氧酶）的共振eraman （RR）光谱分析表明，天然铁酶有两种不同的配位状态。高自旋、精确配位的铁原卟啉IX的证据由Andersson等人提出[Andersson， l.a., Renganathan， V., Chiu， AA, Loehr, t.m., & Gold,]。（1985） J. Biol。而Kuila等人[Kuila， D, Tien， M., Fee， J. A, & Ondrias， M. R.(1985) Biochemistry 24,3394 -3397]提出了一个高自旋，五坐标铁体系。由于两个RR光谱研究是在不同的温度下进行的，我们探索了木质素过氧化物酶可能表现出温度依赖的配位态平衡的可能性。本文给出的共振拉曼结果表明，这一假设是正确的。在25℃或接近25℃时，木质素过氧化物酶的铁主要是高自旋五配位的；然而，在< 2 C时，铁原卟啉IX的自旋和配位状态标记带的频率表明，高自旋和六配位态占主导地位。因此，木质素过氧化物酶的温度依赖性行为与细胞色素c过氧化物酶（CCP）相似。此外，与辣根过氧化物酶（HRP）和CCP一样，木质素过氧化物酶在环境温度下明显与天然第五配体存在空位配位。此外，还给出了木质素过氧化物酶化合物II的高频红外光谱。观察到的氧化状态标记带t/4和自旋和配位状态标记带v0向更高频率的转移与hrp和乳过氧化物酶的化合物II形式以及铁基肌红蛋白的报道相似。这些观察结果与木质素过氧化物酶化合物II的低自旋、六配位Fe (IV)= 0结构相一致。L/木质素是一种复杂的、无光学活性的随机聚合物，占木本植物组织的20-30% （Sarkanen, 1971; Crawford, 1981）。在次生代谢条件下，白腐菌Phanerochaetechrysosporium至少产生两种铁血过氧化物酶（Gold et al., 1984; Kuwahara et al., 1984; Tien & Kirk, 1984; Glenn & Gold, 1985; Paszczynski et al., 1986）并有效地将木质素降解为co2和h2o （Kirk et al., 1978; Gold et al., 1982）。木质素过氧化物酶
Department of Chemical and Biological Sciences, OregonGraduate Center, Beaverton, Oregon 97006-1999 Received October 3, 1986; Revised Manuscript Received December 9, 1986 abstract: ResonanceRaman (RR) spectroscopy of lignin peroxidase (ligninase, diarylpropane oxygenase) from the basidiomycete Phanerochaete chrysosporium suggests two different coordination states for the native ferric enzyme. Evidence for a high-spin, hexacoordinate ferric protoporphyrin IX was presented by Andersson et al.[Andersson, L. A., Renganathan, V., Chiu, AA, Loehr, T. M., & Gold,. H.(1985) J. Biol. Chem. 260, 6080-6087], whereas Kuila et al.[Kuila, D., Tien, M., Fee, J. A., & Ondrias, M. R.(1985) Biochemistry 24, 3394-3397] proposed a high-spin, pentacoordinate ferric system. Because the two RR spectral studies were performed at different temperatures, we explored the possibility that lignin peroxidase might exhibit temperature-dependent coordination-state equilibria. Resonance Raman results presented herein indicatethat thishypothesis is indeed correct. At or near 25 C, the ferric iron of lignin peroxidase is predominantly high spin, pentacoordinate; however, at< 2 C, the high-spin, hexacoordinate state dominates, as indicated by the frequencies of well-documented spin-and coordination-state marker bands for iron protoporphyrin IX. The temperature-dependent behavior of lignin peroxidase is thus similar to that of cytochrome c peroxidase (CCP). Furthermore, lignin peroxidase, like horseradish peroxidase (HRP) and CCP, clearly has a vacant coordination sitetrans to the native fifth ligand at ambient temperature. High-frequency RR spectra of compound II of lignin peroxidase are also presented. The observed shifts to higher frequency for both the oxidation-state marker band t/4 and the spin-and coordination-state marker band vl0 are similar to those reported for the compound II forms ofHRP and lactoperoxidase and for ferryl myoglobin. These observations are consistent with a low-spin, hexacoordinate Fe (IV)= 0 structure for lignin peroxidase compound II.L/ignin is a complex, optically inactive, and random polymer that comprises 20-30% of woody plant tissue (Sarkanen, 1971; Crawford, 1981). Under secondary metabolic conditions the white rot fungus Phanerochaetechrysosporium producesat least two hemeperoxidases (Gold et al., 1984; Kuwahara et al., 1984; Tien & Kirk, 1984; Glenn & Gold, 1985; Paszczynski et al., 1986) and efficiently degrades lignin to C02 and H20 (Kirk et al., 1978; Gold et al., 1982). Lignin peroxidase