Brazzein is the smallest, most stable, member of a family of sweet-tasting proteins. As such Brazzein presents intriguing possibilities for both scientific research and commercial applications. Its unusual thermostability (activity is retained after 2 hours at 90xC) and high potency (500 times sweeter than sucrose on a weight basis) render it a potential candidate for commercial use as a versatile low calorie sweetener. Its other physical properties, wide range of pH stability (from pH 3 to 8) and small size render it an excellent candidate for NMR studies. Complete proton resonance assignments have been obtained from homonuclear 2D NMR data for all 54 residues in the amino acid sequence. The three-dimensional structure of brazzein has been calculated by distance geometry, using constraints derived from 1H-1H NOE crosspeak intensities, 3JHNH? coupling constants, and 3JH?H? coupling constants. The structure contains a helix-turn-helix motif cradled by a three-stranded beta sheet, and has revealed some previously unknown similarities between brazzein and other small cysteine-rich proteins, including scorpion toxins, plant defense proteins, and trypsin inhibitors. The topology of the structure is supported by chemical shift calculations, hydrogen exchange data, and coupling constant information. Studies are now underway to examine possible structural differences between brazzein variants exhibiting different taste properties.

National Institute of Health (NIH)
National Center for Research Resources (NCRR)
Biotechnology Resource Grants (P41)
Project #
Application #
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Wisconsin Madison
United States
Zip Code
Travers, Timothy; López, Cesar A; Van, Que N et al. (2018) Molecular recognition of RAS/RAF complex at the membrane: Role of RAF cysteine-rich domain. Sci Rep 8:8461
Thomas, Nathan E; Wu, Chao; Morrison, Emma A et al. (2018) The C terminus of the bacterial multidrug transporter EmrE couples drug binding to proton release. J Biol Chem 293:19137-19147
Assadi-Porter, Fariba M; Radek, James; Rao, Hongyu et al. (2018) Multimodal Ligand Binding Studies of Human and Mouse G-Coupled Taste Receptors to Correlate Their Species-Specific Sweetness Tasting Properties. Molecules 23:
Wijayatunga, Nadeeja N; Sams, Valerie G; Dawson, John A et al. (2018) Roux-en-Y gastric bypass surgery alters serum metabolites and fatty acids in patients with morbid obesity. Diabetes Metab Res Rev 34:e3045
Assadi-Porter, Fariba M; Reiland, Hannah; Sabatini, Martina et al. (2018) Metabolic Reprogramming by 3-Iodothyronamine (T1AM): A New Perspective to Reverse Obesity through Co-Regulation of Sirtuin 4 and 6 Expression. Int J Mol Sci 19:
Dominguez, Eddie; Zarnowski, Robert; Sanchez, Hiram et al. (2018) Conservation and Divergence in the Candida Species Biofilm Matrix Mannan-Glucan Complex Structure, Function, and Genetic Control. MBio 9:
Franco, Aldo; Dovell, Sanaz; Möller, Carolina et al. (2018) Structural plasticity of mini-M conotoxins - expression of all mini-M subtypes by Conus regius. FEBS J 285:887-902
Wales, Jessica A; Chen, Cheng-Yu; Breci, Linda et al. (2018) Discovery of stimulator binding to a conserved pocket in the heme domain of soluble guanylyl cyclase. J Biol Chem 293:1850-1864
Ting, See-Yeun; Yan, Nicholas L; Schilke, Brenda A et al. (2017) Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23. Elife 6:
Handley, Lindsey D; Fuglestad, Brian; Stearns, Kyle et al. (2017) NMR reveals a dynamic allosteric pathway in thrombin. Sci Rep 7:39575

Showing the most recent 10 out of 613 publications