Campus Units

Biochemistry, Biophysics and Molecular Biology, Chemical and Biological Engineering, Physics and Astronomy, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

2012

Journal or Book Title

Langmuir

Volume

28

Issue

9

First Page

4274

Last Page

4282

DOI

10.1021/la205074n

Abstract

Surface sensitive X-ray scattering and spectroscopic studies have been conducted to determine structural properties of Mms6, the protein in Magnetospirillum magneticum AMB-1 that is implicated as promoter of magnetite nanocrystals growth. Surface pressure versus molecular area isotherms indicate Mms6 forms stable monolayers at the aqueous/vapor interface that are strongly affected by ionic conditions of the subphase. Analysis of X-ray reflectivity from the monolayers shows that the protein conformation at the interface depends on surface pressure and on the presence of ions in the solutions, in particular of iron ions and its complexes. X-ray fluorescence at grazing angles of incidence from the same monolayers allows quantitative determination of surface bound ions to the protein showing that ferric iron binds to Mms6 at higher densities compared to other ions such as Fe2+ or La3+ under similar buffer conditions.

Comments

Reprinted (adapted) with permission from Langmuir 28 (2012) 4274, doi:10.1021/la205074n. Copyright 2012 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

2012_Nilsen_InterfacialProperties_Data.pdf (509 kB)
Supporting Information: Analysis of X-ray reflectivity