Figure 5.

Multibinding interface on ubiquitin domain. (a) Interaction between ubiquitin domain, UBQ (cd01803, 1ZGUB, cyan) and ubiquitin-conjugating enzyme E2 (smart00212, 1ZGUA, red). (b) Interactions between ubiquitin domain (cd01803, 2G3QB, cyan) and ubiquitin-associated domain, UBA (pfam00627, 2G3QA, green). An overlap of 55% is observed on UBQ domain interface and is shown in magenta. Key interface residue I44 on promiscuous interface is shown with the side chain. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]