TY - JOUR
T1 - Drosophila melanogaster aldolase
T2 - Characterization of the isozymes α, β, and γ generated from a single gene
AU - Zhang, Rong
AU - Kai, Tatsuo
AU - Sugimoto, Yasushi
AU - Kusakabe, Takahiro
AU - Takasaki, Yozo
AU - Koga, Katsumi
AU - Hori, Katsuji
PY - 1995/7
Y1 - 1995/7
N2 - Three isozymic forms, α, β, and γ, of Drosophila melanogaster aldolase are produced from a single gene by alternative usage of the triple exons 4 (4α, 4β, and 4γ) (Shaw-Lee et al. (1992) J.Biol. Chem. 267, 3959-3967; Kim et al. (1992) Mol. Cell. Biol. 12, 773-783; Kai et al. (1992) J. Biochem.112, 677-688). The expression plasmids for the respective isozymes were transfected into Escherichia coli cells, and the isozymes α and β were purified to homogeneity by a simple procedure, though isozyme γ was only partially purified. These isozymes are active towards two substrates, fructose-1, 6-bisphosphate (Fru-1, 6-P2) and fructose-1-phosphate (Fru-1-P), with a preference for Fru-1,6-P2 over Fru-1-P, but they have different kcat/Km values towards these two substrates; isozyme α shows the highest kcat/Km value for Fru-1-P among the three isozymes, whereas isozyme β has the highest value for Fru-1,6-P2. These isozymes show similarity in optimal pHs, thermalstability, and Km values for both Fru-1,6-P2 and Fru-1-P. They are composed of four identical subunits of 40 kDa, forming a tetramer with a molecular weight of approximately 160 kDa. The three isozymes are different in primary structure only at the carboxyl-terminal region encoded by the respective exon 4. Therefore, this region should be primarily responsible for the distinct characteristics of these isozymes.
AB - Three isozymic forms, α, β, and γ, of Drosophila melanogaster aldolase are produced from a single gene by alternative usage of the triple exons 4 (4α, 4β, and 4γ) (Shaw-Lee et al. (1992) J.Biol. Chem. 267, 3959-3967; Kim et al. (1992) Mol. Cell. Biol. 12, 773-783; Kai et al. (1992) J. Biochem.112, 677-688). The expression plasmids for the respective isozymes were transfected into Escherichia coli cells, and the isozymes α and β were purified to homogeneity by a simple procedure, though isozyme γ was only partially purified. These isozymes are active towards two substrates, fructose-1, 6-bisphosphate (Fru-1, 6-P2) and fructose-1-phosphate (Fru-1-P), with a preference for Fru-1,6-P2 over Fru-1-P, but they have different kcat/Km values towards these two substrates; isozyme α shows the highest kcat/Km value for Fru-1-P among the three isozymes, whereas isozyme β has the highest value for Fru-1,6-P2. These isozymes show similarity in optimal pHs, thermalstability, and Km values for both Fru-1,6-P2 and Fru-1-P. They are composed of four identical subunits of 40 kDa, forming a tetramer with a molecular weight of approximately 160 kDa. The three isozymes are different in primary structure only at the carboxyl-terminal region encoded by the respective exon 4. Therefore, this region should be primarily responsible for the distinct characteristics of these isozymes.
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U2 - 10.1093/oxfordjournals.jbchem.a124876
DO - 10.1093/oxfordjournals.jbchem.a124876
M3 - Article
C2 - 8537310
AN - SCOPUS:0029082245
VL - 118
SP - 183
EP - 188
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 1
ER -