A thermostable chitinase with chitin-binding activity from Phaseolus limensis.
A 28.6-kDa chitinase with chitin-binding activity was isolated from the large lima bean (Phaseolus limensis) seeds. The procedure entailed extraction, ammonium sulfate precipitation, affinity chromatography on Affi-gel blue gel, and high-performance liquid chromatography (HPLC) on SP-Toyopearl. There was an almost 108-fold increase in specific activity of the purified chitinase compared with that of the crude extract. The enzyme exhibited a pI of 7.8 by isoelectric focusing electrophoresis. The optimum pH and the optimum temperature for activity toward N-acetyld-glucosamine were 5.4 and 40 to 50 degrees C, respectively. The enzyme was stable up to 55 degrees C. It exerted a potent inhibitory action toward fungal species, including Fusarium solani, Pythium aphanidermnatum, and Sclerotium rolfsii.
Wang
S Y
SY
Inst. of Biotechnology, Fuzhou Univ., Fuzhou, Fujian, PR China. shywang@fzu.edu.cn
Zhou
J J
JJ
Shao
B
B
Lu
Y J
YJ
Rao
P F
PF
D000935:Antifungal Agents / Q000302:isolation & purification* / Q000494:pharmacology*; D005591:Chemical Fractionation; D002688:Chitinases / Q000302:isolation & purification* / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005670:Fusarium / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D003904:Mitosporic Fungi / Q000187:drug effects*; D008970:Molecular Weight; D027805:Phaseolus / Q000201:enzymology* / Q000502:physiology; D011775:Pythium / Q000187:drug effects; D012639:Seeds / Q000201:enzymology; D013696:Temperature
D000935:Antifungal Agents; D002688:Chitinases