READING-FRAME SHIFT IN SACCHAROMYCES GLUCOAMYLASES RESTORES CATALYTICBASE, EXTENDS SEQUENCE AND IMPROVES ALIGNMENT WITH OTHER GLUCOAMYLASES

A recent article [Coutinho and Reilly (1994) Protein Engng, 7, 749-760 ] presented the alignment of 14 glucoamylases by hydrophobic cluster a nalysis. The catalytic bases of two of these glucoamylases, from Sacch aromyces cerevisiae and Saccharomyces diastaticus, were not conserved, opening the possibility of a reading-frame shift error in a segment c oding for amino acids near the apparent C-termini of the mature protei ns. Indeed, an addition of one nucleotide restores the catalytic base, extends the sequence by 39 residues and greatly improves the amino ac id alignment in this region.