Vibrational Assignments of Six-Coordinate Ferrous Heme Nitrosyls: New Insight from Nuclear Resonance Vibrational Spectroscopy

被引：42

作者：

Paulat, Florian ^{[1
]}

Berto, Timothy C. ^{[1
]}

George, Serena DeBeer ^{[2
]}

Goodrich, Lauren ^{[1
]}

Praneeth, V. K. K. ^{[1
]}

Sulok, Corinne D. ^{[1
]}

Lehnert, Nicolai ^{[1
]}

机构：

[1] Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA

[2] Stanford Synchrotron Radiat Lab, SLAC, Stanford, CA 94309 USA

来源：

INORGANIC CHEMISTRY | 2008年 / 47卷 / 24期

关键词：

D O I：

10.1021/ic801626w

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

This Communication addresses a long-standing problem: the exact vibrational assignments of the low-energy modes of the Fe-N-O subunit in six-coordinate ferrous heme nitrosyl model complexes. This problem is addressed using nuclear resonance vibrational spectroscopy (NRVS) coupled to (NO)-N-15-O-18 isotope labeling and detailed simulations of the obtained data. Two isotope-sensitive features are identified at 437 and 563 cm(-1). Normal coordinate analysis shows that the 437 cm(-1) mode corresponds to the Fe-NO stretch, whereas the 563 cm(-1) band is identified with the Fe-N-O bend. The relative NRVS intensities of these features determine the degree of vibrational mixing between the stretch and the bend. The implications of these results are discussed with respect to the trans effect of imidazole on the bound NO. In addition, a comparison to myoglobin-NO (Mb-NO) is made to determine the effect of the Mb active site pocket on the bound NO.

引用

页码：11449 / 11451

页数：3

共 10 条

[1]

Ghosh A, 2008, SMALLEST BIOMOLECULES: DIATOMICS AND THEIR INTERACTIONS WITH HEME PROTEINS, P1

[2] Differential sensing of protein influences by NO and CO vibrations in heme adducts [J].