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Mabinlins are sweet-tasting proteins extracted from the seed of Mabinlang (''Capparis masaikai Levl.''), a Chinese plant growing in Yunnan province. There are four homologues. Mabinlin-2 was first isolated in 1983 and characterised in 1993, and is the most extensively studied of the four. The other variants of mabinlin-1, -3 and -4 were discovered and characterised in 1994. == Protein structures == The 4 mabinlins are very similar in their amino acids sequences (see below).
The molecular weights of Mabinlin-1, Mabinlin-3 and Mabinlin-4 are 12.3 kDa, 12.3 kDa and 11.9 kDa, respectively.〔 With a molecular weight of 10.4kDa, mabinlin-2 is lighter than mabinlin-1. It is a heterodimer consisting of two different chains A and B. The A chain is composed of 33 amino acid residues and the B chain is composed of 72 amino acid residues. The B chain contains two intramolecular disulfide bonds and is connected to the A chain through two intermolecular disulfide bridges.〔 Mabinlin-2 is the sweet-tasting protein with the highest known thermostability, which is due to the presence of the four disulfide bridges. It has been suggested also that the difference in the heat stability of the different mabinlin homologues is due to the presence of an arginine residue (heat-stable homologue) or a glutamine (heat-unstable homologue) at position 47 in the B-chain.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Mabinlin」の詳細全文を読む スポンサード リンク
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