TITLE:
A Kunitz trypsin inhibitor from chickpea (Cicer arietinum L.) that exerts an antimicrobial effect on Fusarium oxysporum f.sp. ciceris
AUTHORS:
Meera Nair, Sardul Singh Sandhu
KEYWORDS:
Cicer arietinum; Fusarium Wilt; Kunitz; Proteinase Inhibitor; Trypsin Inhibitor
JOURNAL NAME:
Agricultural Sciences,
Vol.4 No.11,
November
19,
2013
ABSTRACT: Fusarium oxysporum f.sp. ciceris (Foc) is one of the most important fungal pathogens of chickpea and
is regarded as a constant threat in tropical and subtropical countries. In
order to correlate Fusarium wilt resistance/susceptibility in Cicer
arietinum to the presence or absence of trypsin inhibitor (TI) in the crude
extract, trypsin inhibitory
assay (TIA) and in vitro activity of TI against Foc were studied.
In the present study, a 20 kDa trypsin inhibitor was purified from Fusarium wilt
resistant cultivar (viz. JG 2001-12) by ammonium sulfate precipitation, dialysis
and chromatographies with Sephadex G-100 and Diethyl aminoethyl cellulose (DEAE-cellulose-52) ion-exchange column.
Results of pathogenecity assay were found to be in correlation to the trypsin
inhibitor assay where the Fusarium wilt resistant cultivar showed high trypsin
inhibitory activity (99%) in the presence of trypsin enzyme using both natural and synthetic substrates. Preliminary
studies using crude extracts of JG 2001-12 showed a decrease in radial
growth of Foc. A 45%-82% reduction
in conidium germination at 20 μg·mL-1Cicer arietinum trypsin
inhibitor (CaTI) concentration was observed, thereby, indicating
the use of CaTI in suppression of pathogen and in its deployment through transgenic plants for the management of Fusarium wilt.