CLONING AND SEQUENCING OF A CDNA-ENCODING A HEAT-STABLE SWEET PROTEIN, MABINLIN-II

A cDNA clone encoding a heat-stable sweet protein, mabinlin II (MAB), was isolated and sequenced. The encoded precursor to MAB was composed of 155 amino acid (aa) residues, including a signal sequence of 20 aa, an N-terminal extension peptide of 15 aa, a linker peptide of 14 aa a nd one residue of C-terminal extension. Comparison of the proteolytic cleavage sites during posttranslational processing of MAB precursor wi th those of like 2S seed-storage proteins of Arabidopsis thaliana, Bra ssica napus and Bertholletia excelsa shows that the three individual c leavage sites between respective species are conserved.