Residues photolabeled in a tryptic fragment of Japanese Firefly Luciferase (340-QGYGLTETTSAIIITPEGDDKPGASGK-366)an identified by LTQ–FT mass spectrometry and MSMS.

a–d

Same as Table 1.

e

Photoincorporation was either in Ser-249 or Ala-250. The latter residue is rarely labeled by aromatic diazirines.