Explore Structural Aspects

Protein Data Bank(PDB) is the database for experimentally determined proteins solved with X-ray crystallography or NMR studies.

DHFR structure has been determined with bound NADPH cofactor and a lipophilic
antifolate inhibitor.

Open PDB Homepage http://www.rcsb.org/pdb/

In search box write 1KMV that is the PDB ID for this protein, PDB ID is typically four lettered, if you don't have the ID for any protein then you can check Full Text Search option.

Structure Explorer for 1KMV opens. There is lot of information on this page.

You can see or download the structure if you have one of the molecular visualization tools. Most of the topics are very easy to understand. Here is a little insight into PDB structure explorer:-

The initial summary information page gives the details about the title and the source of the protein.

View Structure-You can visualize the structure through various tools.If you have the Java installed onto your computer click on the QuickPDB option.It gives you red colored alpha carbon chain .Explore the structure instantly by rotating, translating or zooming it.

You can learn about the structural neighbors through the next option

Spot the Ramachandran Plot and various options in the Geometry section.

You can the also know amino acid sequence in the Sequence Details options