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Dimerization of the type IV pilin from Pseudomonas aeruginosa strain K122-4 results in increased helix stability as measured by time-resolved hydrogen-deuterium exchange.

ABSTRACT: Truncated pilin monomers from Pseudomonas aeruginosa strain K122-4 (?K122) have been shown to enter a monomer-dimer equilibrium in solution prior to oligomerization into protein nanotubes. Here, we examine the structural changes occurring between the monomeric and dimeric states of ?K122 using time-resolved hydrogen-deuterium exchange mass spectrometry. Based on levels of deuterium uptake, the N-terminal ?-helix and the loop connecting the second and third strands of the anti-parallel ?-sheet contribute significantly to pilin dimerization. Conversely, the antiparallel ?-sheet and ?? loop region exhibit increased flexibility, while the receptor binding domain retains a rigid conformation in the equilibrium state.

SUBMITTER: Lento C

PROVIDER: S-EPMC4711513 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Dimerization of the type IV pilin from Pseudomonas aeruginosa strain K122-4 results in increased helix stability as measured by time-resolved hydrogen-deuterium exchange.

Lento Cristina C Wilson Derek J DJ Audette Gerald F GF

Structural dynamics (Melville, N.Y.) 20150828 1

Truncated pilin monomers from Pseudomonas aeruginosa strain K122-4 (ΔK122) have been shown to enter a monomer-dimer equilibrium in solution prior to oligomerization into protein nanotubes. Here, we examine the structural changes occurring between the monomeric and dimeric states of ΔK122 using time-resolved hydrogen-deuterium exchange mass spectrometry. Based on levels of deuterium uptake, the N-terminal α-helix and the loop connecting the second and third strands of the anti-parallel β-sheet co ...[more]

PMID: 26798830

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