Macromolecular assembly of Helicobacter pylori urease investigated by mass spectrometry.
The supramolecular assembly of Helicobacter pylori urease was studied by nanoflow electrospray ionization orthogonal time-of-flight mass spectrometry. The measured molecular mass of the urease complex of 1.06 MDa corresponds to a dodecameric (alphabeta)(12) assembly of urease alpha (26 kDa) and beta (61 kDa) subunits. The dodecamer disassembles readily into (alphabeta)(3) subunits in solution and under controlled collisional-induced dissociation in the gas phase. This is in strong support of an ((alphabeta)(3))(4) architecture consistent with the recently published x-ray structure. In vitro, the alpha and beta subunits are capable of re-assembling to (alphabeta)(3), but not further to the dodecameric complex.
Pinkse
Martijn W H
MW
Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands.
Maier
Claudia S
CS
Kim
Jung-In
JI
Oh
Byung-Ha
BH
Heck
Albert J R
AJ
D000595:Amino Acid Sequence; D004926:Escherichia coli; D005838:Genotype; D016480:Helicobacter pylori / Q000201:enzymology*; D046911:Macromolecular Substances; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020836:Protein Structure, Quaternary; D021122:Protein Subunits; D017385:Sequence Homology; D021241:Spectrometry, Mass, Electrospray Ionization; D014510:Urease / Q000096:biosynthesis* / Q000737:chemistry*
D046911:Macromolecular Substances; D021122:Protein Subunits; D014510:Urease