Journal Article

Insight into the Spatial Arrangement of the Lysine Tyrosylquinone and Cu 2+ in the Active Site of Lysyl Oxidase-like 2

Moon, Hee-Jung, Mure, Minae, Singh, Priya, Ronnebaum, Trey A, Meier, Alex A, Sabuncu, Sinan, Jackson, Timothy A, Ou, Siyu, Douglas, Justin T, Moënne-Loccoz, Pierre

2022

Overview

Lysyl oxidase-2 (LOXL2) is a Cu and lysine tyrosylquinone (LTQ)-dependent amine oxidase that catalyzes the oxidative deamination of peptidyl lysine and hydroxylysine residues to promote crosslinking of extracellular matrix proteins. LTQ is post-translationally derived from Lys653 and Tyr689, but its biogenesis mechanism remains still elusive. A 2.4 Å Zn -bound precursor structure lacking LTQ (PDB:5ZE3) has become available, where Lys653 and Tyr689 are 16.6 Å apart, thus a substantial conformational rearrangement is expected to take place for LTQ biogenesis. However, we have recently shown that the overall structures of the precursor (no LTQ) and the mature (LTQ-containing) LOXL2s are very similar and disulfide bonds are conserved. In this study, we aim to gain insights into the spatial arrangement of LTQ and the active site Cu in the mature LOXL2 using a recombinant LOXL2 that is inhibited by 2-hydrazinopyridine (2HP). Comparative UV-vis and resonance Raman spectroscopic studies of the 2HP-inhibited LOXL2 and the corresponding model compounds and an EPR study of the latter support that 2HP-modified LTQ serves as a tridentate ligand to the active site Cu . We propose that LTQ resides within 2.9 Å of the active site of Cu in the mature LOXL2, and both LTQ and Cu are solvent-exposed.

• Subject: Catalytic Domain / Lysine - metabolism / Protein-Lysine 6-Oxidase - metabolism / Quinones - chemistry