Title: Monellins
Literature References: Intensely sweet principle from the fruit of the tropical plant Dioscoreophyllum cumminsii Diels, Menispermaceae ("Serendipity Berry"). First believed to consist of a single polypeptide chain of approx 91 amino acids, mol wt about 10,700. Preliminary data and extraction: Inglett, May, J. Food Sci. 34, 408 (1969); Van der Wel, FEBS Lett. 21, 88 (1971); Van der Wel, Loeve, ibid. 29, 181 (1973). Purification: Morris, Cagan, Biochim. Biophys. Acta 261, 114 (1972). Characterized by scientists at the Univ. of Pennsylvania's Monell Chemical Senses Center as the first protein to elicit a sweet taste in man, a "chemostimulatory protein". See Morris et al., J. Biol. Chem. 248, 534 (1973); Cagan, Science 181, 32 (1973). Monellin is composed of two nonidentical subunits: Z. Bohak, S. Li, Biochim. Biophys. Acta 427, 153 (1976); the presence of both subunits is necessary for the sweet taste to occur: B. Jirgenson, ibid. 446, 255 (1976). Structure of subunit I: G. Hudson, K. Biemann, Biochem. Biophys. Res. Commun. 71, 212 (1976). Complete amino acid sequence of subunits A and B consisting of 44 and 50 amino acids, resp.: G. Frank, H. Zuber, Z. Physiol. Chem. 357, 585 (1976). Crystallographic studies: A. Wlodawer, K. Hodgson, Proc. Natl. Acad. Sci. USA 72, 398 (1975); G. E. Tomlinson, S. H. Kim, J. Biol. Chem. 256, 12476 (1981).
Properties: Water soluble. Approximately 3000 times sweeter than sucrose on a weight basis. Essentially free from carbohydrate: <5 mg/mg protein. uv max (0.01M sodium phosphate buffer): 277 nm.
Absorption maximum: uv max (0.01M sodium phosphate buffer): 277 nm
Use: Potential low-calorie sweetener. |