Combining DNP NMR with segmental and specific labeling to study a yeast prion protein strain that is not parallel in-register.
The yeast prion protein Sup35NM is a self-propagating amyloid. Despite intense study, there is no consensus on the organization of monomers within Sup35NM fibrils. Some studies point to a β-helical arrangement, whereas others suggest a parallel in-register organization. Intermolecular contacts are often determined by experiments that probe long-range heteronuclear contacts for fibrils templated from a 1:1 mixture of13C- and15N-labeled monomers. However, for Sup35NM, like many large proteins, chemical shift degeneracy limits the usefulness of this approach. Segmental and specific isotopic labeling reduce degeneracy, but experiments to measure long-range interactions are often too insensitive. To limit degeneracy and increase experimental sensitivity, we combined specific and segmental isotopic labeling schemes with dynamic nuclear polarization (DNP) NMR. Using this combination, we examined an amyloid form of Sup35NM that does not have a parallel in-register structure. The combination of a small number of specific labels with DNP NMR enables determination of architectural information about polymeric protein systems.
Whitehead Institute for Biomedical Research, Cambridge, MA 02142; kendra.frederick@utsouthwestern.edu.
Kendra K
KK
Frederick
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.|Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139.
Vladimir K
VK
Michaelis
Bruker BioSpin, Billerica, MA 01821.
Marc A
MA
Caporini
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.|Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139.
Loren B
0000-0003-3216-9065
LB
Andreas
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.|Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139.
Galia T
GT
Debelouchina
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.|Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139.
Robert G
RG
Griffin
Whitehead Institute for Biomedical Research, Cambridge, MA 02142.|Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02138.|Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02138.
Susan
S
Lindquist
D007553:Isotope Labeling; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010454:Peptide Termination Factors / Q000737:chemistry*; D020836:Protein Structure, Quaternary; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*
D010454:Peptide Termination Factors; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins
Sup35; [PSI+] prion; amyloid; dynamic nuclear polarization; solid-state NMR