title: Structural plasticity in the eight-helix fold of a trematode haemoglobin.
abstract: The three-dimensional structure of recombinant haemoglobin from the trematode Paramphistomum epiclitum, displaying the highest oxygen affinity so far observed for (non)vertebrate haemoglobins, has previously been determined at 1.17 A resolution (orthorhombic space group P2(1)2(1)2(1)). In the present communication, the three-dimensional structure of wild-type P. epiclitum haemoglobin is reported at 1.85 A resolution in a monoclinic crystal form (R factor = 16.1%, R(free) = 22.0%). Comparison of P. epiclitum (recombinant versus wild-type ferric Hb) structures in the two crystal forms shows structural differences in the haem proximal and distal sites which have not been reported for other known haemoglobin structures previously.
authors.affiliation: Department of Physics-INFM, Advanced Biotechnology Centre, University of Genova, Largo Rosanna Benzi 10, I-16146 Genova, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Milani
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pesce
authors.forename: Sylvia
authors.initials: S
authors.lastname: Dewilde
authors.forename: Paolo
authors.initials: P
authors.lastname: Ascenzi
authors.forename: Luc
authors.initials: L
authors.lastname: Moens
authors.forename: Martino
authors.initials: M
authors.lastname: Bolognesi
mesh_terms: D000818:Animals; D018360:Crystallography, X-Ray; D006454:Hemoglobins / Q000737:chemistry*; D008958:Models, Molecular; D010250:Paramphistomatidae / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding
chemical_list: D006454:Hemoglobins