Small ubiquitin-related modifier 2 (SUMO-2) is a member of the SUMO protein family and functions in a manner similar to ubiquitin. However, unlike ubiquitin which targets proteins for degradation, SUMO-2 protein is involved in diverse cellular processes such as nuclear transport, DNA replication and repair, mitosis and signal transduction. This protein is not active until the last two amino acids of the carboxy-terminus have been cleaved off. Recombinant human SUMO2 protein was expressed in E. coli and purified by using conventional chromatography.