Lysine biosynthesis naturally occurs through two different pathways: the α-aminoadipate (AAA) pathway and the diaminopimelate (DAP) pathway. The first and rate-limiting step of the DAP pathway is catalysed by the dihydrodipicolinate synthase (DHDPS). Although previous literature suggests that DHDPS is present in lower fungi and a structure of a putative DHDPS from the fungus Coiccidioides immitis has recently been deposited in the PDB, no experimental data has been described to date that validates fungal DHDPS exists. Furthermore, no study has clearly identified where the separation between DAP and AAA pathways occurs in lower fungi. This study set out to characterise the activity of DHDPS in the fungus kingdom. Putative DHDPS encoding genes were firstly identified from Genbank and the PDB databases from two species (C. immitis and Fonsecae pedrosoi), and the genes cloned into expression vectors to yield milligram quantities of purified recombinant products. Enzyme kinetic data revealed that the product from C. immitis possesses no DHDPS activity but instead functions as a KDG aldolase, whereas the recombinant enzyme from F. pedrosoi contains both weak DHDPS and KDG aldolase activity suggesting this product may be an evolutionary relic at the divergence point between these class I aldolases. These results suggest that fungi do not commonly contain DHDPS enzymes and the DAP pathway, but instead may rely predominantly on the AAA pathway to synthesize lysine.