Preliminary X-ray crystallographic analysis of a nitric oxide-inducible lactate dehydrogenase from Staphylococcus aureus

Recent studies have indicated that Staphylococcus aureus can survive the nitrosative stress (caused by the radical nitric oxide; NO·) mounted by the immune system of the infected host. It does this by expressing a nitric oxide-inducible l-lactate dehydrogenase (Sa-LDH-1). Therefore, if efficient inhibitors of Sa-LDH-1 can be designed then Sa-LDH-1 could be a potential drug target against the pathogen S. aureus. For this purpose, the nitric acid-inducible LDH-1 from S. aureus COL strain has been cloned into the expression vector pET-28a(+) and the protein has been expressed, purified and crystallized. The Sa-LDH-1 crystal diffracted to 2.4 Å resolution at a home X-ray source and belonged to space group C2, with unit-cell parameters a = 131.4, b = 74.4, c = 103.2 Å, β = 133.4°.