Major isoforms of starch branching enzymes in premature seeds of kidney bean (Phaseolus vulgaris L.).
Developing seeds of the kidney bean (Phaseolus vulgaris L.) contain several isoforms of starch branching enzymes. Two of them, KBE1 and KBE2, which are the major forms in the premature seeds, were purified as a single band of protein on SDS-PAGE and native PAGE by chromatographies on DEAE-Sepharose, Bio-Gel P-200, and amylose-binding Sepharose 6B. The enzymes had similar pH optimum (7.0), pH stability (7.0-9.5), temperature optimum (25-30 degrees C), and temperature stability (up to 40 degrees C). Additionally, both were inhibited by various divalent metal ions and activated by citrate. Finally, though their N-terminal amino acid sequences were identical, their molecular masses and affinities for amylose differed; 80 kDa and 1.27 mM for KBE1 and 77 kDa and 0.74 mM for KBE2.
Nozaki
K
K
Department of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo, Japan.
Hamada
S
S
Nakamori
T
T
Ito
H
H
Sagisaka
S
S
Yoshida
H
H
Takeda
Y
Y
Honma
M
M
Matsui
H
H
D015061:1,4-alpha-Glucan Branching Enzyme / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000595:Amino Acid Sequence; D002118:Calcium / Q000737:chemistry; D002850:Chromatography, Gel; D019343:Citric Acid / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D007887:Fabaceae / Q000196:embryology / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D012639:Seeds / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid; D013696:Temperature
D019343:Citric Acid; D015061:1,4-alpha-Glucan Branching Enzyme; D002118:Calcium