Preliminary X-ray crystallographic analysis of a novel maltogenic amylase from Bacillus stearothermophilus ET1.
A novel maltogenic amylase from Bacillus stearothermophilus ET1, which has a dual activity of alpha-1,4- and alpha-1,6-glycosidic bond cleavages and alpha-1,6-glycosidic bond formation, was crystallized by using the hanging-drop vapor-diffusion method. The best crystals were obtained by employing a high concentration of protein (56 mg ml-1) and a precipitant containing 22% glycerol, 1.6 M ammonium sulfate in 0.1 M Tris-HCl (pH 8.5). Native diffraction data to 2.66 A resolution have been obtained from crystals flash-frozen at 110 K. The crystals belong to the space group P212121 with unit-cell dimensions of a = 77.62, b = 121.23, c = 244. 29 A, and contain three or four protomers per asymmetric unit. Structure determination by multiple isomorphous replacement is in progress.
Cho
M J
MJ
Department of Life Sciences and School of Environmental Engineering, Pohang University of Science and Technology, Hyoja-dong, San 31, Pohang, Kyungbuk 790-784, Korea.
Cha
S S
SS
Park
J H
JH
Cha
H J
HJ
Lee
H S
HS
Park
K H
KH
Oh
B H
BH
D000681:Amylases / Q000737:chemistry*; D018360:Crystallography, X-Ray / Q000379:methods*; D004058:Diffusion; D001411:Geobacillus stearothermophilus / Q000201:enzymology*
D000681:Amylases