support for working with 'large 3D structures'

Jalview 2 supports traditional PDB format data import, which has some limitations when working with large 3D structures - such as those generated by electron microscopy and other modern techniques.

The main limitation of PDB files in this context is that only 62 chains can be represented. There may be others. Consequently, the wwwPDB recommend mmCIF, xPDB or another modern 3D structure format be used for download of large structures.