Purification and characterization of novel raw-starch-digesting and cold-adapted alpha-amylases from Eisenia foetida.
Novel raw-starch-digesting and cold-adapted alpha-amylases (Amy I and Amy II) from the earthworm Eisenia foetida were purified to electrophoretically homogeneous states. The molecular weights of both purified enzymes were estimated to be 60,000 by SDS-PAGE. The enzymes were most active at pH 5.5 and 50 degrees C and stable at pH 7.0-9.0 and 50-60 degrees C. Both Amy I and II exhibited activities at 10 degrees C. The enzymes were inhibited by metal ions Cu(2+), Fe(2+), and Hg(2+), and hydrolyzed raw starch into glucose, maltose and maltotriose as end products.
Ueda
Mitsuhiro
M
Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka, 599-8531, Japan. mueda@biochem.osakafu-u.ac.jp
Asano
Tomohiko
T
Nakazawa
Masami
M
Miyatake
Kazutaka
K
Inouye
Kuniyo
K
D000220:Adaptation, Biological / Q000187:drug effects; D000818:Animals; D002855:Chromatography, Thin Layer; D003080:Cold Temperature; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability / Q000187:drug effects; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D006868:Hydrolysis / Q000187:drug effects; D008670:Metals / Q000494:pharmacology; D008970:Molecular Weight; D009835:Oligochaeta / Q000201:enzymology*; D012275:Oryza / Q000378:metabolism; D020539:Sequence Analysis, Protein; D012995:Solubility / Q000187:drug effects; D013213:Starch / Q000378:metabolism*; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry / Q000302:isolation & purification*
D008670:Metals; D013213:Starch; D000516:alpha-Amylases