Purification and characterization of a thermophilic and acidophilic chitinase from Microbispora sp. V2.
OBJECTIVE
Purification and characterization of a chitinase from Microbispora sp. V2.


RESULTS
The chitinase from Microbispora sp. V2 was purified to homogeneity by gel filtration chromatography with 4.6% recovery. It had a molecular weight of 35 kDa and showed maximum activity towards p-nitrophenyl-beta-d-N,N'-diacetylchitobiose, indicating a chitobiosidase activity. The enzyme had a pH optimum of 3.0 and temperature optimum of 60 degrees C. It was stable in a wide pH range from 3.0 to 11.0, retaining 61% activity at pH 3.0 and 52% activity at pH 11.0. It retained 71% activity at 30 degrees C and 45% activity at 50 degrees C, up to 24 h. The enzyme activity was not inhibited by any of the metal ions tested except Hg2+, in the presence of which only 10% activity was retained.


CONCLUSIONS
The 35 kDa chitinase from Microbispora sp. V2 has an acidic pH optimum and a high temperature optimum. It is fairly stable and active, and degrades chitin efficiently, although the growth of the culture and enzyme production is slow.


CONCLUSIONS
This report is the first detailed study of a chitinase from Microbispora sp. V2, isolated from hot springs. The chitinase from Microbispora sp. V2 may have potential applications in the recycling of chitinous wastes, particularly due to its thermophilic and acidophilic character. Studies at molecular level may provide further insight on the chitinolytic system of Microbispora spp. with respect to the number and types of chitinases and their regulation.
Nawani
N N
NN
Department of Microbiology, University of Pune, Pune and Molecular Biology and Agriculture Division, Bhabha Atomic Research Centre, Mumbai, India.
Kapadnis
B P
BP
Das
A D
AD
Rao
A S
AS
Mahajan
S K
SK
D039903:Actinobacteria / Q000201:enzymology*; D001426:Bacterial Proteins / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002688:Chitinases / Q000302:isolation & purification*; D002850:Chromatography, Gel; D005618:Fresh Water; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration
D001426:Bacterial Proteins; D002688:Chitinases