9ISM

Cryo-EM structure of MxaF/MxaJ complex

Summary for 9ISM

• Entry DOI: 10.2210/pdb9ism/pdb
• EMDB information: 60838
• Descriptor: Methanol dehydrogenase, alpha subunit, Methanol oxidation protein MxaJ (2 entities in total)
• Functional Keywords: mxaf/mxaj, protein binding
• Biological source: Methylorubrum extorquens (Methylobacterium dichloromethanicum, Methylobacterium extorquens); More
• Total number of polymer chains: 4
• Total formula weight: 203607.98

Authors

Sun, J.Q.,Gao, F. (deposition date: 2024-07-18, release date: 2025-07-23, Last modification date: 2025-07-30)

Primary citation

Zhou, H.,Sun, J.,Cheng, J.,Wu, M.,Bai, J.,Li, Q.,Shen, J.,Han, M.,Yang, C.,Li, L.,Liu, Y.,Cao, Q.,Liu, W.,Xiao, H.,Dong, H.,Gao, F.,Jiang, H.
Deciphering the assembly process of PQQ dependent methanol dehydrogenase.
Nat Commun, 16:6672-6672, 2025

PubMed Abstract: Pyrroloquinoline quinone (PQQ)-dependent methanol dehydrogenases (MDHs), the periplasmic metalloenzymes in Gram-negative methylotrophic bacteria, play a pivotal role in methane and methanol bio-utilization. Although the structures of many PQQ-dependent MDHs have been resolved, including the canonical heterotetrameric enzymes composed of two MxaF and two MxaI subunits with a molecule of PQQ and a calcium ion in the active site in MxaF, the biogenesis of these enzymes remains elusive. Here, we characterize a chaperone, MxaJ, responsible for PQQ incorporation by reconstructing a PQQ-dependent MDH assembly system in Escherichia coli. Using cryo-electron microscopy, we capture the structures of the intermediate complexes formed by the chaperone MxaJ and catalytic subunit MxaF during PQQ-dependent MDH maturation, revealing a chaperone-mediated molecular mechanism of cofactor incorporation. These findings not only advance our understanding on the biogenesis of PQQ-dependent MDH, but also provide an alternative engineering way for methane and methanol bioconversion.

PubMed: 40683858
DOI: 10.1038/s41467-025-61958-w

Experimental method

ELECTRON MICROSCOPY (2.78 Å)