Gallery Molecular Models Gallery OxyhaemoglobinBreathe in! Human oxyhaemoglobin. This glossy model shows the four subunits of haemoglobin.OxyhaemoglobinFour subunits of haemoglobin. The two alpha subunits are in white and black; the two beta subunits are in light and medium grey.OxyhaemoglobinThe haem group in each monomer subunit is in red and shows where an O2 molecule binds – four dioxygens per haemoglobin tetramer.OxyhaemoglobinCut-away model through the middle of haemoglobin to reveal the complex polypeptide chain folding inside the molecule.COX-2 with aspirin moleculesHow aspirin works: structure of the enzyme cyclooxygenase 2 (COX-2). COX-2, is a homodimer and in this model the subunits are coloured white and blue; the haem group in each subunit required for prostaglandin synthesis is shown in red.COX-2 with aspirin moleculesCOX-2, also known as prostaglandin H2 synthase, is inhibited by the anti-inflammatory drug aspirin. Aspirin molecules are shown to scale alongside. Model made for the Biochemical Society outreach team.C.Csp231IThis 2 part magnetic model shows how the complex assembles.C.Csp231IStructure of the Restriction-Modification controller protein C.Csp231I.C.Csp231IThis protein consists of two dimers (orange/yellow and light/dark blue) that interact to hold the DNA in a loop.Nucleosome FibreSix models of the 50 nm nucleosome fibre. Each model represents a different theoretical inter-nucleosomal spacing; nucleosomes are shown as yellow and orange spheres.Nucleosome FibreThese images shows how useful physical models can be for inspecting and evaluating molecular structures.Nucleosome FibreThese images shows how useful physical models can be for inspecting and evaluating molecular structures.