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Article
Self-assembly and biphasic iron-binding characteristics of Mms6, a bacterial protein that promotes the formation of superparamagnetic magnetite nanoparticles of uniform size and shape
Biomacromolecules
  • Lijun Wang, Iowa State University
  • Tanya Prozorov, Iowa State University
  • Pierre E. Palo, Iowa State University
  • Xunpei Liu, Iowa State University
  • David Vaknin, Iowa State University
  • Ruslan Prozorov, Iowa State University
  • Surya K. Mallapragada, Iowa State University
  • Marit Nilsen-Hamilton, Iowa State University
Document Type
Article
Publication Date
1-1-2012
DOI
10.1021/bm201278u
Abstract

Highly ordered mineralized structures created by living organisms are often hierarchical in structure with fundamental structural elements at nanometer scales. Proteins have been found responsible for forming many of these structures, but the mechanisms by which these biomineralization proteins function are generally poorly understood. To better understand its role in biomineralization, the magnetotactic bacterial protein, Mms6, which promotes the formation in vitro of superparamagnetic magnetite nanoparticles of uniform size and shape, was studied for its structure and function. Mms6 is shown to have two phases of iron binding: one high affinity and stoichiometric and the other low affinity, high capacity, and cooperative with respect to iron. The protein is amphipathic with a hydrophobic N-terminal domain and hydrophilic C-terminal domain. It self-assembles to form a micelle, with most particles consisting of 20-40 monomers, with the hydrophilic C-termini exposed on the outside. Studies of proteins with mutated C-terminal domains show that the C-terminal domain contributes to the stability of this multisubunit particle and binds iron by a mechanism that is sensitive to the arrangement of carboxyl/hydroxyl groups in this domain.

Comments

Reprinted with permission from Biomacromolecules 13 (2012): pp. 98 - 105, doi: 10.1021/bm201278u. Copyright 2011 American Chemical Society.

Copyright Owner
American Chemical Society
Language
en
Date Available
2014-12-09
File Format
application/pdf
Citation Information
Lijun Wang, Tanya Prozorov, Pierre E. Palo, Xunpei Liu, et al.. "Self-assembly and biphasic iron-binding characteristics of Mms6, a bacterial protein that promotes the formation of superparamagnetic magnetite nanoparticles of uniform size and shape" Biomacromolecules Vol. 13 Iss. 1 (2012) p. 98 - 105
Available at: http://works.bepress.com/marit-nilsen-hamilton/20/