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.
Department of Life Sciences and School of Environmental Engineering, Pohang University of Science and Technology, Hyoja-dong, San 31, Pohang, Kyungbuk 790-784, Korea.
M J
MJ
Cho
S S
SS
Cha
J H
JH
Park
H J
HJ
Cha
H S
HS
Lee
K H
KH
Park
B H
BH
Oh
D000681:Amylases / Q000737:chemistry*; D018360:Crystallography, X-Ray / Q000379:methods*; D004058:Diffusion; D001411:Geobacillus stearothermophilus / Q000201:enzymology*
D000681:Amylases