[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 ArticlesProbing 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 properties of its solvent-exposed loop, two residues (Arg-Ile) were inserted between Leu18 and Ala19 of brazzein. Psychophysical testing demonstrated that this mutant is totally tasteless. NMR chemical shift mapping of differences between this mutant and brazzein indicated that residues affected by the insertion are localized to the mutated loop, the region of the single alpha-helix, and around the Cys16-Cys37 disulfide bond. Residues unaffected by this mutation included those near the C-terminus and in the loop connecting the alpha-helix and the second beta-strand. In particular, several residues of brazzein previously shown to be essential for its sweetness (His31, Arg33, Glu41, Arg43, Asp50, and Tyr54) exhibited negligible chemical shift changes. Moreover, the pH dependence of the chemical shifts of His31, Glu41, Asp50, and Tyr54 were unaltered by the insertion. The insertion led to large chemical shift and pKa perturbation of Glu36, a residue shown previously to be important for brazzein's sweetness. These results serve to refine the known sweetness determinants of brazzein and lend further support to the idea that the protein interacts with a sweet-taste receptor through a multi-site interaction mechanism, as has been postulated for brazzein and other sweet proteins (monellin and thaumatin).
[NMR paper] NMR analysis shows that a b-type variant of Hydrogenobacter thermophilus cytochrome c
NMR analysis shows that a b-type variant of Hydrogenobacter thermophilus cytochrome c552 retains its native structure.
Related Articles NMR analysis shows that a b-type variant of Hydrogenobacter thermophilus cytochrome c552 retains its native structure.
J Biol Chem. 2004 Apr 9;279(15):15177-82
Authors: Wain R, Redfield C, Ferguson SJ, Smith LJ
Conversion of Hydrogenobacter thermophilus cytochrome c(552) into a b-type cytochrome by mutagenesis of both heme-binding cysteines to alanines significantly reduces the stability of the protein...
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11-24-2010 09:25 PM
[NMR paper] Correlation of the sweetness of variants of the protein brazzein with patterns of hyd
Correlation of the sweetness of variants of the protein brazzein with patterns of hydrogen bonds detected by NMR spectroscopy.
Related Articles Correlation of the sweetness of variants of the protein brazzein with patterns of hydrogen bonds detected by NMR spectroscopy.
J Biol Chem. 2003 Aug 15;278(33):31331-9
Authors: Assadi-Porter FM, Abildgaard F, Blad H, Markley JL
In sequence-function investigations, approaches are needed for rapidly screening protein variants for possible changes in conformation. Recent NMR methods permit direct...
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11-24-2010 09:01 PM
[NMR paper] Probing the surface of a sweet protein: NMR study of MNEI with a paramagnetic probe.
Probing the surface of a sweet protein: NMR study of MNEI with a paramagnetic probe.
Related Articles Probing the surface of a sweet protein: NMR study of MNEI with a paramagnetic probe.
Protein Sci. 2001 Aug;10(8):1498-507
Authors: Niccolai N, Spadaccini R, Scarselli M, Bernini A, Crescenzi O, Spiga O, Ciutti A, Di Maro D, Bracci L, Dalvit C, Temussi PA
The design of safe sweeteners is very important for people who are affected by diabetes, hyperlipemia, and caries and other diseases that are linked to the consumption of sugars. Sweet...
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11-19-2010 08:44 PM
[NMR paper] Sequence-dependent correction of random coil NMR chemical shifts.
Sequence-dependent correction of random coil NMR chemical shifts.
Related Articles Sequence-dependent correction of random coil NMR chemical shifts.
J Am Chem Soc. 2001 Apr 4;123(13):2970-8
Authors: Schwarzinger S, Kroon GJ, Foss TR, Chung J, Wright PE, Dyson HJ
Random coil chemical shifts are commonly used to detect secondary structure elements in proteins in chemical shift index calculations. While this technique is very reliable for folded proteins, application to unfolded proteins reveals significant deviations from measured random coil...
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11-19-2010 08:32 PM
[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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11-18-2010 08:31 PM
[NMR paper] The NMR solution structure and characterization of pH dependent chemical shifts of th
The NMR solution structure and characterization of pH dependent chemical shifts of the beta-elicitin, cryptogein.
Related Articles The NMR solution structure and characterization of pH dependent chemical shifts of the beta-elicitin, cryptogein.
J Biomol NMR. 1998 Nov;12(4):523-34
Authors: Gooley PR, Keniry MA, Dimitrov RA, Marsh DE, Keizer DW, Gayler KR, Grant BR
The NMR structure of the 98 residue beta-elicitin, cryptogein, which induces a defence response in tobacco, was determined using 15N and 13C/15N labelled protein samples. In aqueous...
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11-17-2010 11:15 PM
[NMR paper] 13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-
13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-Trp variants of Escherichia coli thioredoxin.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-cellhub.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles 13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-Trp variants of Escherichia coli thioredoxin.
Biophys J. 1994 Jun;66(6):2111-26
Authors: Kemple MD, Yuan...
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[NMR paper] 13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-
13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-Trp variants of Escherichia coli thioredoxin.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-cellhub.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles 13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-Trp variants of Escherichia coli thioredoxin.
Biophys J. 1994 Jun;66(6):2111-26
Authors: Kemple MD, Yuan...
Probing the sweet determinants of brazzein: wild-type brazzein and a tasteless variant, brazzein-ins(R18a-I18b), exhibit different pH-dependent NMR chemical shifts.
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