Kinetic, structural, and spectroscopic identification of geminate states of myoglobin: a ligand binding site on the reaction pathway.
Kinetic, structural, and spectroscopic identification of geminate states of myoglobin: a ligand binding site on the reaction pathway.
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肌红蛋白成对状态的动力学、结构和光谱鉴定：反应途径上的配体结合位点。
DOI：
10.1021/bi00389a028
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发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
Zhou,Y
中科院分区：
文献类型：
--
作者：
Powers,L;Chance,B;Chance,M;Campbell,B;Friedman,J;Khalid,S;Kumar,C;Naqui,A;Reddy,KS;Zhou,Y
AT&T贝尔实验室，Murray Hill，新泽西07974，宾夕法尼亚大学生物化学和生物物理系，宾夕法尼亚州费城19104结构和功能研究所，东北希尔大学生命科学学院，Shillong 793 014，印度，1986年8月5日接收; 1987年2月11日接收修订版摘要：气态配体与转运蛋白反应的基本步骤或成对状态描绘了配体的轨迹及其与血红素的再结合。通过对765 nm光学“构象”谱带的动力学研究，在低于~ 100 K的温度下确定了三个孪晶态。在1.2和~ 10 K之间通过光解积累的MB* CO通过我们先前的光学和X射线吸收研究表征[Chance，B.，菲谢蒂河，& Powers，L.（1983）Biochemistry 22，3820-3829]。在10和~ 100 K之间，还鉴定了具有~ 103* s-1和~ 10 - 5 s-1（40 K）的复合率的孪晶态。因此，有可能通过调节的连续照明（光泵浦）来维持最慢重组双生状态Mb** 的稳态几乎均匀的群体。X射线吸收和共振拉曼研究表明，在类似的光泵浦条件下，在Mb** 中的铁周围的血红素结构是类似的Mb* CO。在这两种孪合态，铁的近端组氨酸距离保持不变（±0.02 A）的Mb CO，而铁吡咯氮的平均距离没有完全放松的脱氧状态。在Mb* CO中，CO保持接近铁但不结合，并且在Mb CO（127±4 ° C）中弯曲的Fe-CO角减小约15 [Powers，L.，Sessler，J. L.，Woolery，G. L.，& Chance，B.（1984）Biochemistry 23，5519-5523]。然而，Mb** 中的CO分子已经从miron进一步移动了大约0.7 A。MbCO晶体结构的计算机图形模拟将CO置于血红素口袋中的缝隙中，该缝隙刚好足够大以使CO分子端接。高于约100 K的共振拉曼研究表明，该结构弛豫到脱氧态。由于配体与蛋白质结合之前和之后的静态结构已经被很好地表征，因此，寻找和表征配体与蛋白质结合过程中的中间状态现在是各种研究的主要焦点。动力学研究是适当的，以确定的时间和温度域中的中间状态可以被隔离。血红素蛋白的羰基、亚硝酰基和氧化合物已经为此类研究提供了模型系统（Austin等人，1973; Iizuka等人，1974 a）。Yonetani小组表明，在低温下血红蛋白和肌红蛋白（Mb）的CO光产物具有从脱氧物质移位的近红外吸收光谱（Iizuka等人，1974 b; Yonetani等人，1973年）。随后，Frauenfelder及其同事在10 - 5至1.0秒的时间尺度上观察到复合反应的幂律动力学（Ansari等人，1985; Austin等人，1975; Frauenfelder，1985）。这些结果证明了单闪光肌红蛋白动力学的复杂性，并提供了许多可能的中间状态的证据。光泵浦，采用在恒定温度下调节的连续照明，允许许多光解转换产生稳态f的可能性。这项工作部分得到NIH赠款HL-18708，GM-
AT&T Bell Laboratories, Murray Hill, New Jersey 07974, Department of Biochemistry and Biophysics, University of Pennsylvania, and Institute for Structural and Functional Studies, Philadelphia, Pennsylvania 19104, and School of Life Sciences, Northeastern Hill University, Shillong 793 014, India Received August 5, 1986; Revised Manuscript Received February 11, 1987 abstract: Elementary steps or geminate states in the reaction of gaseous ligands with transport proteins delineate the trajectory of the ligand and its rebinding to the heme. By use of kinetic studies of the 765-nm optical “conformation” band, three geminate states were identified for temperatures less than~ 100 K. Mb* CO, which is accumulated by photolysis between 1.2 and~ 10 K, was characterized by our previous optical and X-ray absorption studies [Chance, B., Fischetti, R., & Powers, L.(1983) Biochemistry 22, 3820-3829]. Between 10 and~ 100 K, geminate states are also identified that have recombination rates of~ 103* s" 1 and~ 10~ 5 s_1 (40 K). Thus, it is possible to maintain a steady-state nearly homogeneous population of the slowest recombining geminate state, Mb**, by regulated continuous illumination (optical pumping). Both X-ray absorption and resonance Raman studies under similar conditions of optical pumping show that the heme structure around the iron in Mb** is similar to that of Mb* CO. In both geminate states, the iron-proximal histidine distance remains unchanged (±0.02 A) from that of MbCO while the iron to pyrrole nitrogen average distance has not fully relaxed to that of the deoxy state. In Mb* CO the CO remains close to iron but not bound, and the Fe—CO angle, which is bent in MbCO (127±4 C), is decreased by~ 15 [Powers, L., Sessler, J. L., Woolery, G. L., & Chance, B.(1984) Biochemistry 23, 5519-5523], The CO molecule in Mb**, however, has moved approximately 0.7 A further fromiron. Computer graphics modeling of the crystal structure of MbCO places the CO in a crevice in the heme pocket that is just large enough for the CO molecule end-on. Above approximately 100 K resonance Raman studies show that this structure relaxes to the deoxy state. e search for and the characterization of intermediate states in the process of ligand binding to proteins are now the principal focus of a variety of studies since the static structures, prior and subsequent to ligand binding, have been well characterized. Kinetic studies are appropriate for identifying the time and temperature domains in which intermediate states can be isolated. The carbonyl, nitrosyl, and oxygen compounds of heme proteins have provided model systems for such studies (Austin et al., 1973; Iizuka et al, 1974a). The Yonetani group showed that the CO photoproducts of hemoglobin and myoglobin (Mb) at low temperatures have near-infrared absorption spectra shifted from the deoxy species (Iizuka et al., 1974b; Yonetani et al., 1973). Subsequently, Frauenfelder and colleagues observed power law kineticsfor the recombination reaction on time scales from 10'5 to 1.0 s (Ansari et al., 1985; Austin et al., 1975; Frauenfelder, 1985). These results demonstrate the complexity of single-flash myoglobin kinetics and provide evidence for many possible intermediate states. Optical pumping, which employs regulated continuous il-lumination at a constant temperature, allows for the possibility of numerous photolysis turnovers producing steady-state f This work was supported in part by NIH Grants HL-18708, GM-
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低温下碳氧肌红蛋白光产物的结构和动力学：X 射线吸收研究。
影响因子：
2.9
作者：
B. Chance;R. Fischetti;L. Powers
通讯作者：
L. Powers
低温下光解肌红蛋白-CO 的穆斯堡尔光谱研究。
DOI：
10.1111/j.1432-1033.1979.tb13020.x
发表时间：
1979
期刊：
European journal of biochemistry
影响因子：
--
作者：
H. E. Marcolin;R. Reschke;A. Trautwein
通讯作者：
A. Trautwein
一氧化碳与分离的血红蛋白链的结合。
影响因子：
2.9
作者：
N. Alberding;S. S. Chan;L. Eisenstein;H. Frauenfelder;D. Good;I. C. Gunsalus;T. Nordlund;M. Perutz;A. H. Reynolds;L. Sorensen
通讯作者：
L. Sorensen
原子和分子轨道的等高线曲面
影响因子：
3
作者：
E. A. Ogryzlo;G. Porter
通讯作者：
G. Porter
影响因子：
56.9
作者：
AUSTIN, RH;BEESON, K;MARSHALL, VP
通讯作者：
MARSHALL, VP