In sequence-function investigations, approaches are needed for rapidly screening protein variants for possible changes in conformation. Recent NMR methods permit direct detection of hydrogen bonds through measurements of scalar couplings that traverse hydrogen bonds (trans-hydrogen bond couplings). We have applied this approach to screen a series of five single site mutants of the sweet protein brazzein with altered sweetness for possible changes in backbone hydrogen bonding with respect to wild-type. Long range, three-dimensional data correlating connectivities among backbone 1HN, 15N, and 13C' atoms were collected from the six brazzein proteins labeled uniformly with carbon-13 and nitrogen-15. In wild-type brazzein, this approach identified 17 backbone hydrogen bonds. In the mutants, altered magnitudes of the couplings identified hydrogen bonds that were strengthened or weakened; missing couplings identified hydrogen bonds that were broken, and new couplings indicated the presence of new hydrogen bonds. Within the series of brazzein mutants investigated, a pattern was observed between sweetness and the integrity of particular hydrogen bonds. All three "sweet" variants exhibited the same pattern of hydrogen bonds, whereas all three "non-sweet" variants lacked one hydrogen bond at the middle of the alpha-helix, where it is kinked, and one hydrogen bond in the middle of beta-strands II and III, where they are twisted. Two of the non-sweet variants lack the hydrogen bond connecting the N and C termini. These variants showed greater mobility in the N- and C-terminal regions than wild-type brazzein.
Application of SAIL phenylalanine and tyrosine with alternative isotope-labeling patterns for protein structure determination
Application of SAIL phenylalanine and tyrosine with alternative isotope-labeling patterns for protein structure determination
Abstract The extensive collection of NOE constraint data involving the aromatic ring signals is essential for accurate protein structure determination, although it is often hampered in practice by the pervasive signal overlapping and tight spin couplings for aromatic rings. We have prepared various types of stereo-array isotope labeled phenylalanines (ε- and ζ-SAIL Phe) and tyrosine (ε-SAIL Tyr) to overcome these problems (Torizawa et al. 2005), and proven...
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[NMR paper] Probing the sweet determinants of brazzein: wild-type brazzein and a tasteless variant, brazzein-ins(R18a-I18b), exhibit different pH-dependent NMR chemical shifts.
Probing the sweet determinants of brazzein: wild-type brazzein and a tasteless variant, brazzein-ins(R18a-I18b), exhibit different pH-dependent NMR chemical shifts.
Related Articles Probing the sweet determinants of brazzein: wild-type brazzein and a tasteless variant, brazzein-ins(R18a-I18b), exhibit different pH-dependent NMR chemical shifts.
Biochem Biophys Res Commun. 2005 Sep 16;335(1):256-63
Authors: Zhao Q, Song J, Jin Z, Danilova V, Hellekant G, Markley JL
Brazzein is a small, intensely sweet protein. As a probe of the functional...
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[NMR paper] Characterization of the structure and dynamics of amyloidogenic variants of human lys
Characterization of the structure and dynamics of amyloidogenic variants of human lysozyme by NMR spectroscopy.
Related Articles Characterization of the structure and dynamics of amyloidogenic variants of human lysozyme by NMR spectroscopy.
Protein Sci. 2001 Dec;10(12):2525-30
Authors: Chamberlain AK, Receveur V, Spencer A, Redfield C, Dobson CM
The structures and dynamics of the native states of two mutational variants of human lysozyme, I56T and D67H, both associated with non-neuropathic systemic amyloidosis, have been investigated by NMR...
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11-19-2010 08:44 PM
[NMR paper] NMR structures of three single-residue variants of the human prion protein.
NMR structures of three single-residue variants of the human prion protein.
Related Articles NMR structures of three single-residue variants of the human prion protein.
Proc Natl Acad Sci U S A. 2000 Jul 18;97(15):8340-5
Authors: Calzolai L, Lysek DA, Guntert P, von Schroetter C, Riek R, Zahn R, Wüthrich K
The NMR structures of three single-amino acid variants of the C-terminal domain of the human prion protein, hPrP(121-230), are presented. In hPrP(M166V) and hPrP(R220K) the substitution is with the corresponding residue in murine PrP, and in...
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[NMR paper] Studies on solution NMR structure of brazzein : Secondary structure and molecular sca
Studies on solution NMR structure of brazzein : Secondary structure and molecular scaffold.
Related Articles Studies on solution NMR structure of brazzein : Secondary structure and molecular scaffold.
Sci China C Life Sci. 1999 Aug;42(4):409-19
Authors: Gao G, Dai J, Ding M, Hellekant G, Wang J, Wang D
Brazzein is a sweet-tasting protein isolated from the fruit of West African plantPentadiplandra brazzeana Baillon. It is the smallest and the most water-soluble sweet protein discovered so far and is highly thermostable. The proton NMR study of...
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[NMR paper] Full 1H NMR assignment and detailed O-acetylation patterns of capsular polysaccharide
Full 1H NMR assignment and detailed O-acetylation patterns of capsular polysaccharides from Neisseria meningitidis used in vaccine production.
Related Articles Full 1H NMR assignment and detailed O-acetylation patterns of capsular polysaccharides from Neisseria meningitidis used in vaccine production.
Carbohydr Res. 1996 Dec 24;296:83-96
Authors: Lemercinier X, Jones C
We report essentially complete 1H NMR assignments for the capsular polysaccharides from Neisseria meningitidis serotypes A, C, W-135, and Y. These polysaccharides are components...
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08-22-2010 02:20 PM
[NMR paper] NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c i
NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c in which unvaried aromatic residues have been substituted.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif Related Articles NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c in which unvaried aromatic residues have been substituted.
Eur J Biochem. 1991 Dec 5;202(2):339-47
Authors: Thurgood AG, Davies AM, Greenwood C, Mauk AG, Smith M,...
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[NMR paper] NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c i
NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c in which unvaried aromatic residues have been substituted.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif Related Articles NMR study of the structural characteristics of variants of yeast iso-1-cytochrome c in which unvaried aromatic residues have been substituted.
Eur J Biochem. 1991 Dec 5;202(2):339-47
Authors: Thurgood AG, Davies AM, Greenwood C, Mauk AG, Smith M,...