Will the real FeCO please stand up?

被引:42
作者
Spiro, TG
Kozlowski, PM
机构
[1] Department of Chemistry, Princeton University, Princeton
来源
JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY | 1997年 / 2卷 / 04期
关键词
myoglobin-CO; bond distortion; bond energy; CO poisoning; hydrogen bond; infrared; Raman;
D O I
10.1007/s007750050164
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The paradigm that nature protects us from CO poisoning by forcing the bound CO to bend over in heme proteins, thereby reducing its binding affinity, is now in textbooks, but is nevertheless problematic. Results from vibrational spectroscopy give no evidence for bent CO, although X-ray crystallography continues to indicate appreciable distortions in myoglobin. However, the energetic significance of the discrepancy is doubtful, since new Density Functional Theory calculations indicate that much less energy is required to distort the CO than had been thought, perhaps 2 kcal/mol or less. Binding studies on site-directed mutants of myoglobin suggest that steric hindrance by the distal histidine is worth ca. 1 kcal/mol. While the distal histidine does account for the discrimination by Mb against CO and in favor of O-2, most of the effect is due to its H-bond with bound O-2.
引用
收藏
页码:516 / 520
页数:5
相关论文
共 41 条
[11]   DETERMINATION OF CO ORIENTATION IN MYOGLOBIN BY SINGLE-CRYSTAL INFRARED LINEAR DICHROISM [J].
IVANOV, D ;
SAGE, JT ;
KEIM, M ;
POWELL, JR ;
ASHER, SA ;
CHAMPION, PM .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1994, 116 (09) :4139-4140
[12]   THE PROXIMAL RESIDUE LARGELY DETERMINES THE CO DISTORTION IN CARBON MONOXY GLOBIN PROTEINS - AN AB INITO STUDY OF A HEME PROSTHETIC UNIT [J].
JEWSBURY, P ;
YAMAMOTO, S ;
MINATO, T ;
SAITO, M ;
KITAGAWA, T .
JOURNAL OF PHYSICAL CHEMISTRY, 1995, 99 (33) :12677-12685
[13]  
JEWSBURY P, 1994, J AM CHEM SOC, V116, P11587
[14]   SYNTHESIS, CHARACTERIZATION, CRYSTAL-STRUCTURES, AND CO AND O2 BINDING-PROPERTIES OF NOVEL 4-ATOM-LINKED CAPPED PORPHYRINS [J].
JOHNSON, MR ;
SEOK, WK ;
IBERS, JA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1991, 113 (10) :3998-4000
[15]   STRUCTURAL CHARACTERIZATION OF A STERICALLY ENCUMBERED IRON(II) PORPHYRIN CO COMPLEX [J].
KIM, K ;
FETTINGER, J ;
SESSLER, JL ;
CYR, M ;
HUGDAHL, J ;
COLLMAN, JP ;
IBERS, JA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (01) :403-405
[16]   STRUCTURE OF A CARBON-MONOXIDE ADDUCT OF A CAPPED PORPHYRIN - FE(C2-CAP)(CO)(1-METHYLIMIDAZOLE) [J].
KIM, K ;
IBERS, JA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1991, 113 (16) :6077-6081
[17]   EVIDENCE FOR HYDROGEN-BONDING OF BOUND DIOXYGEN TO THE DISTAL HISTIDINE OF OXYCOBALT MYOGLOBIN AND HEMOGLOBIN [J].
KITAGAWA, T ;
ONDRIAS, MR ;
ROUSSEAU, DL ;
IKEDASAITO, M ;
YONETANI, T .
NATURE, 1982, 298 (5877) :869-871
[18]   X-RAY STRUCTURE AND REFINEMENT OF CARBON-MONOXY (FE-II)-MYOGLOBIN AT 1.5-A RESOLUTION [J].
KURIYAN, J ;
WILZ, S ;
KARPLUS, M ;
PETSKO, GA .
JOURNAL OF MOLECULAR BIOLOGY, 1986, 192 (01) :133-154
[19]   STRUCTURAL DETERMINANTS OF THE STRETCHING FREQUENCY OF CO BOUND TO MYOGLOBIN [J].
LI, TS ;
QUILLIN, ML ;
PHILLIPS, GN ;
OLSON, JS .
BIOCHEMISTRY, 1994, 33 (06) :1433-1446
[20]   IS BOUND CO LINEAR OR BENT IN HEME-PROTEINS - EVIDENCE FROM RESONANCE RAMAN AND INFRARED SPECTROSCOPIC DATA [J].
LI, XY ;
SPIRO, TG .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1988, 110 (18) :6024-6033