Glutathione S-transferase 1 from Necator americanus (Na-GST-1) is a vaccine
candidate for hookworm infection that has a high affinity for heme and metal
porphyrins. As part of attempts to clarify the mechanism of heme detoxification
by hookworm GSTs, co-crystallization and soaking studies of Na-GST-1 with the
heme-like molecules protoporphyrin IX disodium salt, hematin and zinc
protoporphyrin were undertaken. While these studies did not yield the structure
of the complex of Na-GST-1 with any of these molecules, co-crystallization
experiments resulted in the first structures of the complex of Na-GST-1 with the
substrate glutathione. The structures of the complex of Na-GST-1 with
glutathione were solved from pathological crystalline aggregates comprising more
than one crystal form. These first structures of the complex of Na-GST-1 with
the substrate glutathione were solved by molecular replacement from data
collected with a sealed-tube home source using the previously reported apo
structure as the search model.
