E2 conjugating enzyme that associates with the E3 ubiquitin-protein ligase EL5 to mediates ubiquitination of target proteins. S-ubiquitinyl-[E1 ubiquitin-activating enzyme]-L-cysteine + [E2 ubiquitin-conjugating enzyme]-L-cysteine = [E1 ubiquitin-activating enzyme]-L-cysteine + S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine. Protein modification; protein ubiquitination. By N-acetylchitooligosaccharide elicitor. Belongs to the ubiquitin-conjugating enzyme family.