Crystallization and preliminary analysis of crystals of the 24-meric hemocyanin of the emperor scorpion (Pandinus imperator).

Hemocyanins are giant oxygen transport proteins found in the hemolymph of several invertebrate phyla. They constitute giant multimeric molecules whose size range up to that of cell organelles such as ribosomes or even small viruses. Oxygen is reversibly bound by hemocyanins at binuclear copper centers.

Structure of the altitude adapted hemoglobin of guinea pig in the R2-state.

Background: Guinea pigs are considered to be genetically adapted to a high altitude environment based on the consistent finding of a high oxygen affinity of their blood.

Methodology/principal Findings: The crystal structure of guinea pig hemoglobin at 1.8 A resolution suggests that the increased oxygen affinity of guinea pig hemoglobin can be explained by two factors, namely a decreased stability of the T-state and an increased stability of the R2-state.

Monte Carlo-based rigid body modelling of large protein complexes against small angle scattering data.

We present a modular, collaborative, open-source architecture for rigid body modelling based upon small angle scattering data, named sas_rigid. It is designed to provide a fast and extensible scripting interface using the easy-to-learn Python programming language. Features include rigid body modelling to result in static structures and three-dimensional probability densities using two different algorithms.

Crystallization of the altitude adapted hemoglobin of guinea pig.

Hemoglobin is the versatile oxygen carrier in the blood of vertebrates and a key factor for adaptation to live in high altitudes. Several structural changes are known to account for increased oxygen affinity in hemoglobin of altitude adapted animals such as llama and barheaded goose. Guinea pigs are adapted to live in high altitudes in the Andes and consequently their hemoglobin has an increased oxygen affinity.