Two Distinct L-Lactate Dehydrogenases Play a Role in the Survival of Neisseria gonorrhoeae in Cervical Epithelial Cells.

L-lactate is an abundant metabolite in a number of niches in host organisms and represents an important carbon source for bacterial pathogens such as Neisseria gonorrhoeae. In this study, we describe an alternative, iron-sulfur cluster-containing L-lactate dehydrogenase (LutACB), that is distinct from the flavoprotein L-lactate dehydrogenase (LldD). Expression of lutACB was found to be positively regulated by iron, whereas lldD was more highly expressed under conditions of iron-limitation. The functional role of LutACB and LldD was reflected in in vitro studies of growth and in the survival of N gonorrhoeae in primary cervical epithelial cells.