The primary structure of the subunit in Bacillus thermoamyloliquefaciens KP1071 molecular weight 540,000 homohexameric alpha-glucosidase II belonging to the glycosyl hydrolase family 31.
The gene that coded for the subunit of an molecular weight (Mr) 540,000 homohexameric alpha-glucosidase II (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) produced by Bacillus thermoamyloliquefaciens KP1071 (FERM-P8477) growing at 30 to 66 degrees C was expressed in Escherichia coli HB101. The resulting homohexameric enzyme had a half-life of 10 min at 80 degrees C. Its purification and characterization showed that the enzyme was identical with the native one except for the latter deleting 7 N-terminal residues found in the former. The primary sequence of the subunit with 787 residues and an Mr of 91,070 deduced from the gene was 24-34% identical to the corresponding sequences of 15 alpha-glucosidases in the glycosyl hydrolase family 31 from 14 eukaryotic origins and the archaeon Sulfolobus solfataricus 98/2. From the sequence analysis by the neural network method of Rost and Sander [Rost, B. and Sander, C., Proteins: Struct. Funct. Genet., 19, 55-72 (1994)], we inferred that alpha-glucosidase II might make each subunit of 3 secondary structural regions, i.e., one N-terminal beta region, one central alpha/beta region with two catalytic residues Asp407 and Asp484, and one C-terminal beta region.
Kashiwabara
S
S
Department of Applied Biochemistry, Kyoto Prefectural University, Japan.
Azuma
S
S
Tsuduki
M
M
Suzuki
Y
Y
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001407:Bacillus / Q000201:enzymology*; D001483:Base Sequence; D004269:DNA, Bacterial; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011817:Rabbits; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D000520:alpha-Glucosidases / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000302:isolation & purification
D000596:Amino Acids; D004269:DNA, Bacterial; D000520:alpha-Glucosidases