Substrates accepted by SxtG including α-amino ketones, α-amino methyl esters, and other primary amines. Percent conversions were determined by LC-MS quantification of products. Reactions consisted of 1 μM SxtG, 1 mM substrate, 10 mM L-Arg (2), 500 μM Fe(NH4)2(So4)2, and 50 mM HEPES pH 8.5 and were incubated at 30 °C for 16 h.