Molecular mechanism for ligand stabilization in the mollusc myoglobin possessing the distal Val residue

Yamamoto, Yasuhiko; Iwafune, Koji; Chûjô, Riichirǒ; Inoue, Yoshio; Imai, Katsunori; Suzuki, Tomohiko

doi:10.1016/0022-2836(92)90823-3

Cited by 27 publications

(6 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In several derivatives of Aplysia ferrimyoglobin, the side chain of arginine-ElO, which appears to be disordered in the unliganded structure, is folded back into the heme pocket so that the guanidinium group makes favorable interactions with the ligand (Conti et al, 1993). This is consistent with results from NMR studies of the cyanomet derivatives of myoglobins from Aplysia and Dolabella auricularia which also has a valine at the E7 position (Qin et al, 1992;Yamamoto et al, 1992). If arginine-ElO adopts a similar conformation in the ferrous oxy complex of these mollusc myoglobins, it could compensate for the absence of the distal histidine by forming a hydrogen bond with bound oxygen.…”

supporting

confidence: 79%

Interactions among residues CD3, E7, E10, and E11 in myoglobins: Attempts to simulate the ligand-binding properties of Aplysia myoglobin

Smerdon¹,

Krzywda²,

Brzozowski³

et al. 1995

Biochemistry

View full text Add to dashboard Cite

Site-directed mutations have been introduced singly and in combination at residues lysine/arginine45 (CD3), histidine64 (E7), threonine67 (E10), and valine68 (E11) in pig and sperm whale myoglobins. The mutations probe the roles of these key distal pocket residues and represent attempts to mimic the heme environment of Aplysia limacina myoglobin which achieves moderately high O2 affinity in the absence of a distal histidine. In the mollusc myoglobin, arginine-E10 is believed to swing into the heme pocket and provide a hydrogen bond to the bound O2. The association and dissociation rate constants for oxygen and carbon monoxide binding to H64V, T67A, T67V, T67E, T67R, V68I, V68T, H64V-T67R, H64V-V68T, H64V-V68I, and H64V-T67R-V68I pig myoglobin mutants and T67R, H64V-T67R, and R45D-H64V-T67R mutants of sperm whale myoglobin have been measured using stopped-flow rapid mixing and flash photolysis techniques. Replacement of histidine-E7 with valine in either pig or sperm whale myoglobin drastically lowers O2 affinity while increasing CO affinity. Two second-site mutations, T67R and V68T, increase O2 affinity in the H64V mutant, even though when introduced singly these mutations have no effect or lower KO2, respectively. However, the oxygen affinities of the H64V-T67R mutants are 5-10-fold lower than that of A. limacina myoglobin. The crystal structure of the pig H64V-T67R double mutant reveals that the valine-E7 side chain is approximately 1 A closer to the heme plane than in the mollusc protein which may restrict access of the arginine-E10 side chain into the heme pocket. The O2 affinity of the H64V-T67R double mutant is not altered by the R45D replacement but is reduced 10-fold by the V68I mutation. The interactive effects of the T67R, V68I, and V68T mutations with the H64V substitution are discussed in terms of O2, CO, and N3-binding and the crystal structures of the H64V-T67R, H64V-V68I, and H64V-V68T double-mutant proteins. In many instances, the effects of second-site mutations in the valine64 background are the opposite of those observed for the corresponding single mutations in the wild type background. These results can be understood in terms of the changes in the rate-determining steps for ligand association and dissociation and the loss of distal pocket water molecules which follow replacement of histidine64 by valine.

show abstract

supporting

confidence: 79%

Interactions among residues CD3, E7, E10, and E11 in myoglobins: Attempts to simulate the ligand-binding properties of Aplysia myoglobin

Smerdon¹,

Krzywda²,

Brzozowski³

et al. 1995

Biochemistry

View full text Add to dashboard Cite

show abstract

“…This creates together with B10-Phe a very hydrophobic distal side with no residue able to form a hydrogen bond with the bound oxygen. Stabilisation of the oxygen might therefore occur, as in Aplysia Mb, by the E10-Arg (25)(26)(27) (Fig. 3).…”

Section: Primary Structure Of Globin A1mentioning

confidence: 96%

Protein and Gene Structure of a Chlorocruorin Chain of Eudistylia vancouverii

Dewilde

Hauwaert

Vinogradov

et al. 2001

Biochemical and Biophysical Research Communications

View full text Add to dashboard Cite

“…The most important distal interaction for stabilizing bound O 2 is hydrogen bonding to the ligand, for which the donor is generally His E7 (1,7,9,10) and is Gln E7 in a few cases (2). In several invertebrates, such as Aplysia and Dolbella Mbs that possess a Val E7, the distal H bond to the ligand is provided by an Arg at position E10 (11)(12)(13).…”

mentioning

confidence: 99%

1H NMR Investigation of the Distal Hydrogen Bonding Network and Ligand Tilt in the Cyanomet Complex of Oxygen-avidAscaris suum Hemoglobin

Xia

Zhang

Nguyen

et al. 1999

Journal of Biological Chemistry

View full text Add to dashboard Cite

The O 2 -avid hemoglobin from the parasitic nematode Ascaris suum exhibits one of the slowest known O 2 off rates. Solution 1 H NMR has been used to investigate the electronic and molecular structural properties of the active site for the cyano-met derivative of the recombinant first domain of this protein. Assignment of the heme, axial His, and majority of the residues in contact with the heme reveals a molecular structure that is the same as reported in the A. suum HbO 2 crystal structure (Yang, J., Kloek, A., Goldberg, D. E., and Mathews, F. S. (1995) Proc. Natl. Acad. Sci. U. S. A. 92, 4224 -4228) with the exception that the heme in solution is rotated by 180°about the ␣,␥-meso axis relative to that in the crystal. The observed dipolar shifts, together with the crystal coordinates of HbO 2 , provide the orientation of the magnetic axes in the molecular framework. The major magnetic axis, which correlates with the Fe-CN vector, is found oriented ϳ30°away from the heme normal and indicates significant steric tilt because of interaction with Tyr 30 (B10). The three side chain labile protons for the distal residues Tyr 30 (B10) and Gln 64 (E7) were identified, and their relaxation, dipolar shifts, and nuclear Overhauser effects to adjacent residues used to place them in the distal pocket. It is shown that these two distal residues exhibit the same orientations ideal for H bonding to the ligand and to each other, as found in the A. suum HbO 2 crystal. It is concluded that the ligated cyanide participates in the same distal H bonding network as ligated O 2 . The combination of the strong steric tilt of the bound cyanide and slow ring reorientation of the Tyr 30 (B10) side chain supports a crowded and constrained distal pocket.The O 2 binding globins, myoglobin (Mb) 1 and hemoglobin (Hb), despite highly varied sequences throughout phylogeny, possess a highly conserved folding topology of 7-8 helices (A-H), with the heme wedged in between the E and F helices and ligated by one, His F8 (proximal), of only two (the other is Phe CD1) completely conserved residues (1-3). Despite this strong structural homology, the O 2 ligation rates and O 2 affinities vary over a remarkably wide range (by ϳ10 5 ), depending on the exact nature of several distal residues at the key positions B10, E7, and E10 (4 -8). The most important distal interaction for stabilizing bound O 2 is hydrogen bonding to the ligand, for which the donor is generally His E7 (1, 7, 9, 10) and is Gln E7 in a few cases (2). In several invertebrates, such as Aplysia and Dolbella Mbs that possess a Val E7, the distal H bond to the ligand is provided by an Arg at position E10 (11-13).A particularly noteworthy class of globins is that of parasitic nematodes that possess, in addition to a H bond donor at position E7, a Tyr at position B10 that is also capable of H bonding to the ligand (4, 5, 8, 14 -17 (5,15). The positions of these two key residues are clearly defined in the crystal structure of A. suum HbO 2 , in which the two residues are appropriately poised ...

show abstract

Molecular mechanism for ligand stabilization in the mollusc myoglobin possessing the distal Val residue

Cited by 27 publications

References 28 publications

Interactions among residues CD3, E7, E10, and E11 in myoglobins: Attempts to simulate the ligand-binding properties of Aplysia myoglobin

Interactions among residues CD3, E7, E10, and E11 in myoglobins: Attempts to simulate the ligand-binding properties of Aplysia myoglobin

Protein and Gene Structure of a Chlorocruorin Chain of Eudistylia vancouverii

1H NMR Investigation of the Distal Hydrogen Bonding Network and Ligand Tilt in the Cyanomet Complex of Oxygen-avidAscaris suum Hemoglobin

Contact Info

Product

Resources

About