You can find more information about Ubc13 using the following links:

PFID PFID Old Formal Annotation PlasmoDB TDR Targets Subcellular Localization Affecting Drugs
Drug Name PubMed Articles (year of publication)
PF3D7_0527100 PFE1350c ubiquitin-conjugating enzyme E2 13 PlasmoDB TDR
dihydroartemisinin
Expasy - NiceZime View
Brenda - The Comprehensive Enzyme Information System