PBG Synthase

PDB file 1GZG

This file depicts Porphobilinogen Synthase from Pseudomonas aeruginosa in complex with 5-fluorolevulinic acid, an analog for the substrate d-aminolevulinic acid (ALA). This structure was solved by F. Frère, W.-D. Schubert, F. Stauffer, N. Frankenberg, R. Neier, D. Jahn & D. W. Heinz in 2002.

Suggested display options:

Select color chain and display the protein as cartoon. Two copies of the enzyme are present.

Select ligand, display as ball & stick with color CPK, to visualize the 5-fluorolevulinic acid substrate analog.
d-Aminolevulinic acid (ALA) in Schiff base linkage is shown below.

Note that there are 2 copies of the substrate analog at each active site.
Focus on the active site in which the structures are well resolved (chain A, the darker blue protein).
Identify the Na⁺ ion that interacts with the fluorine atoms (replacing amino groups) of both substrate analogs.
(You might want to select atom NA and display spacefill.)

Select lys205, lys260. Display as ball & stick with color CPK.
Identify atoms involved in the Schiff base linkage between each substrate analog and one of the active site lysine residues.

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