Diane E. Zimmerman

A novel RNA-binding motif in influenza A virus non-structural protein 1.

The solution NMR structure of the RNA-binding domain from influenza virus non-structural protein 1 exhibits a novel dimeric six-helical protein fold. Distributions of basic residues and conserved salt bridges of dimeric NS1(1-73) suggest that the face containing antiparallel helices 2 and 2′ forms a novel arginine-rich nucleic acid binding motif.

Automated sequencing of amino acid spin systems in proteins using multidimensional HCC(CO)NH-TOCSY spectroscopy and constraint propagation methods from artificial intelligence

SummaryWe have developed an automated approach for determining the sequential order of amino acid spin systems in small proteins. A key step in this procedure is the analysis of multidimensional HCC(CO)NH-TOCSY spectra that provide connections from the aliphatic resonances of residue i to the amide resonances of residue i+1. These data, combined with information about the amino acid spin systems, provide sufficient constraints to assign most proton and nitrogen resonances of small proteins. Constraint propagation methods progressively narrow the set of possible assignments of amino acid spin systems to sequence-specific positions in the process of NMR data analysis. The constraint satisfaction paradigm provides a framework in which the necessary constraint-based reasoning can be expressed, while an object-oriented representation structures and facilitates the extensive list processing and indexing involved in matching. A prototype expert system, AUTOASSIGN, provides correct and nearly complete resonance assignments with one real and 31 simulated 3D NMR data sets for a 72-amino acid domain, derived from the Protein A of Staphylococcus aureus, and with 31 simulated NMR data sets for the 50-amino acid human type-α transforming growth factor.

Automated analysis of nuclear magnetic resonance assignments for proteins

Recent developments in protein NMR technology provide spectral data that are highly amendable to analysis by computer software systems. Automated methods of analysis use constraint satisfaction, pseudoenergy minimization, directed search, neural net, simulated annealing, and/or genetic algorithms to establish sequential links and sequence-specific assignments. The most advanced systems provide automated analysis of complete backbone and extensive side-chain resonance assignments for proteins of 50-150 amino acids.

High Resolution Solution NMR Structure of the Z Domain of Staphylococcal Protein A. Analysis of Secondary Structure for Free Z Domain and Bounded to IgG Antibody

Staphylococcal protein A (SpA) is a cell-wall-bound pathogenicity factor from the bacterium Staphylcoccus aureus. It exhibits tight binding to many IgG, IgA and IgM molecules at site(s) different from antigen-combining site. Because of their small size and immunoglobulin (IgG)-binding activities, domains of protein A are important targets for protein engineering efforts and for the development of computational approaches for de novo protein folding.