One‐Step Chemical Synthesis of Native Met1‐Linked Poly‐Ubiquitin Chains

다국어 초록 (Multilingual Abstract)

The enzyme‐mediated construction of poly‐ubiquitin (Ub) chains on target proteins leads to a variety of cellular responses and is involved in processes ranging from protein degradation to cell cycle control and immune responses. This complex post‐translational modification system is under intense investigation, but generation of specific Ub chains and tools made thereof is not always trivial. We discovered that native methionine‐1‐linked polymeric ubiquitin chains can be constructed in a single chemical reaction. We validate correct folding and regioselective attachment of such chains using linkage specific proteases and further demonstrate that these poly‐Ub chains can be converted into thioesters by the activating E1‐enzyme. Subsequent ligation reactions using these in situ prepared thioesters leads to poly‐ubiquitinated peptides.
Chain reaction: Native methionine‐1‐linked polymeric ubiquitin chains can be constructed in a single chemical reaction based on solid‐phase peptide synthesis (SPPS) on routinely used trityl‐resin. Correct folding and regioselective attachment of such chains is shown using linkage specific proteases. These poly‐Ub chains can be converted into thioesters by the activating E1‐enzyme and used in subsequent native chemical ligation reactions.