A computer molecular model of a protein nanotube which was visualized using the Protein Data Bank viewer module of growler. Nanotubes are thermosome protein subunits and are made from the bacterium Thermoplasma acidophilum. This is a chaperonin heat shock protein, one that protects the bacterium from damage by high temperatures. The crystal structure from the PDB actually contains information for only a single pair of red and green strands and the viewer imposes symmetry operations to arrange eight pairs around the circumference of the tube (which is also opened up to expose its interior). The green and yellow spheres represent amino acid residues.