Infrared spectroscopic discrimination between the loop and alpha-helices and determination of the loop diffusion kinetics by temperature-jump time-resolved infrared spectroscopy for cytochrome c
文献类型：期刊论文
| 作者 | Ye, MP ; Zhang, QL ; Li, H ; Weng, YX ; Wang, WC ; Qiu, XG |
| 刊名 | BIOPHYSICAL JOURNAL
 |
| 出版日期 | 2007 |
| 卷号 | 93期号:8页码:2756 |
| ISSN号 | 0006-3495 |
| 中文摘要 | The infrared (IR) absorption of the amide I band for the loop structure may overlap with that of the alpha-helices, which can lead to the misassignment of the protein secondary structures. A resolution-enhanced Fourier transform infrared (FTIR) spectroscopic method and temperature-jump (T-jump) time-resolved IR absorbance difference spectra were used to identify one specific loop absorption from the helical IR absorption bands of horse heart cytochrome c in D2O at a pD around 7.0. This small loop consists of residues 70-85 with Met-80 binding to the heme Fe(III). The FTIR spectra in amide I' region indicate that the loop and the helical absorption bands overlap at 1653 cm(-1) at room temperature. Thermal titration of the amide I' intensity at 1653 cm(-1) reveals that a transition in loop structural change occurs at lower temperature (T-m = 45 degrees C), well before the global unfolding of the secondary structure (T-m = 82 degrees C). This loop structural change is assigned as being triggered by the Met-80 deligation from the heme Fe(III). T-jump time-resolved IR absorbance difference spectra reveal that a T-jump from 25 degrees C to 35 degrees C breaks the Fe-S bond between the Met-80 and the iron reversibly, which leads to a loop (1653 cm(-1), overlap with the helical absorption) to random coil (1645 cm(-1)) transition. The observed unfolding rate constant interpreted as the intrachain diffusion rate for this 16 residue loop was similar to 3.6 x 10(6) s(-1). |
| 收录类别 | SCI |
| 公开日期 | 2013-09-18 |
| 源URL | [http://ir.iphy.ac.cn/handle/311004/39964]  |
| 专题 | 物理研究所_物理所公开发表论文_物理所公开发表论文_期刊论文 |
| 推荐引用方式 GB/T 7714 | Ye, MP,Zhang, QL,Li, H,et al. Infrared spectroscopic discrimination between the loop and alpha-helices and determination of the loop diffusion kinetics by temperature-jump time-resolved infrared spectroscopy for cytochrome c[J]. BIOPHYSICAL JOURNAL,2007,93(8):2756. |
| APA | Ye, MP,Zhang, QL,Li, H,Weng, YX,Wang, WC,&Qiu, XG.(2007).Infrared spectroscopic discrimination between the loop and alpha-helices and determination of the loop diffusion kinetics by temperature-jump time-resolved infrared spectroscopy for cytochrome c.BIOPHYSICAL JOURNAL,93(8),2756. |
| MLA | Ye, MP,et al."Infrared spectroscopic discrimination between the loop and alpha-helices and determination of the loop diffusion kinetics by temperature-jump time-resolved infrared spectroscopy for cytochrome c".BIOPHYSICAL JOURNAL 93.8(2007):2756. |
入库方式： OAI收割
来源：物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。