Linkage-specific ubiquitin binding interfaces modulate the activity of the chlamydial deubiquitinase Cdu1 towards poly-ubiquitin substrates.

The chlamydial deubiquitinase Cdu1 of the obligate intracellular human pathogenic bacterium Chlamydia trachomatis plays important roles in the maintenance of chlamydial infection. Despite the structural similarities shared with its homologue Cdu2, both DUBs display remarkable differences in their enzymatic activity towards poly-UB chain substrates. Whereas Cdu1 is highly active towards K48- and K63- poly-UB chains, Cdu2 activity is restricted mostly to mono-UB substrates.

Enzymatic Nitrogen Incorporation Using Hydroxylamine.

Hydroxylamine-derived reagents have enabled versatile nitrene transfer reactions for introducing nitrogen-containing functionalities in small-molecule catalysis, as well as biocatalysis. These reagents, however, result in a poor atom economy and stoichiometric organic waste. Activating hydroxylamine (NHOH) for nitrene transfer offers a low-cost and sustainable route to amine synthesis, since water is the sole byproduct.