TY - JOUR
T1 - The 109 residue nerve tissue minihemoglobin from Cerebratulus lacteus highlights striking structural plasticity of the α-helical globin fold
AU - Pesce, Alessandra
AU - Nardini, Marco
AU - Dewilde, Sylvia
AU - Geuens, Eva
AU - Yamauchi, Kiyoshi
AU - Ascenzi, Paolo
AU - Riggs, Austen F.
AU - Moens, Luc
AU - Bolognesi, Martino
PY - 2002
Y1 - 2002
N2 - A very short hemoglobin (CerHb; 109 amino acids) binds O2 cooperatively in the nerve tissue of the nemertean worm Cerebratulus lacteus to sustain neural activity during anoxia. Sequence analysis suggests that CerHb tertiary structure may be unique among the known globin fold evolutionary variants. The X-ray structure of oxygenated CerHb (R factor 15.3%, at 1.5 Å resolution) displays deletion of the globin N-terminal A helix, an extended GH region, a very short H helix, and heme solvent shielding based on specific aromatic residues. The heme-bound O2 is stabilized by hydrogen bonds to the distal TyrB10-GlnE7 pair. Ligand access to heme may take place through a wide protein matrix tunnel connecting the distal site to a surface cleft located between the E and H helices.
AB - A very short hemoglobin (CerHb; 109 amino acids) binds O2 cooperatively in the nerve tissue of the nemertean worm Cerebratulus lacteus to sustain neural activity during anoxia. Sequence analysis suggests that CerHb tertiary structure may be unique among the known globin fold evolutionary variants. The X-ray structure of oxygenated CerHb (R factor 15.3%, at 1.5 Å resolution) displays deletion of the globin N-terminal A helix, an extended GH region, a very short H helix, and heme solvent shielding based on specific aromatic residues. The heme-bound O2 is stabilized by hydrogen bonds to the distal TyrB10-GlnE7 pair. Ligand access to heme may take place through a wide protein matrix tunnel connecting the distal site to a surface cleft located between the E and H helices.
KW - Globin fold plasticity
KW - Nerve tissue minihemoglobin
KW - Oxygen binding
KW - Oxygenated hemoglobin
KW - Protein cavities
KW - X-ray crystallography
UR - http://www.scopus.com/inward/record.url?scp=0036098845&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036098845&partnerID=8YFLogxK
U2 - 10.1016/S0969-2126(02)00763-3
DO - 10.1016/S0969-2126(02)00763-3
M3 - Article
C2 - 12015154
AN - SCOPUS:0036098845
VL - 10
SP - 725
EP - 735
JO - Structure with Folding & design
JF - Structure with Folding & design
SN - 0969-2126
IS - 5
ER -