To gain further insight into how the presence of a 2'-OH substituent on the ribonucleoside donor influences substrate recognition and subsequent catalytic steps, structural studies were conducted on the wildtype LlNDT-2 and a double mutant Y7F/D72N. These two mutations were chosen based on the enhanced acceptance of a ribonucleoside donor in an enzymatic transglycosylation reaction by an analogous double mutant of a Type I NDT derived from Trypanosoma brucei (TbNDT). The corresponding Y7F/D72N mutant of LlNDT-2 showed inferior catalytic transglycosylation compared to the wildtype enzyme using a range of nucleoside donor and nucleobases (Figure ).