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 resistan...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-1?Cicer 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.展开更多
It was widely thought that 3 variants of Kunitz type trypsin inhibitor(SBTi A 2) existed in soybean seed storage protein.Three of codominant alleles Ti a,Ti b and Ti c were identified to decode these SBTi A 2 inhibito...It was widely thought that 3 variants of Kunitz type trypsin inhibitor(SBTi A 2) existed in soybean seed storage protein.Three of codominant alleles Ti a,Ti b and Ti c were identified to decode these SBTi A 2 inhibitors and the amino acid sequences of them were determined,of which one or more different amino acid were found.Ti d was a new variant allele of SBTi A 2 discovered after analyzing more than 15 000 samples of soybean seed in China.In order to study the structure features of Ti d protein,the amino acid sequence of this protein was deduced from its coding region which was amplified by PCR from soybean genomic DNA and sequenced.By comparison with Ti a protein,two different amino acid residue were found between Ti a and Ti d proteins.One was an extra Ala inserted in the signal peptide of Ti d,with 8 residues from N terminal,and the other existed in the mature protein,with Glu 69 in Ti a protein turned into Lys 69 in Ti d protein.The amino acid sequence of Ti d mature protein was also different from those of Ti a and Ti b.展开更多
文摘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-1?Cicer 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.
文摘It was widely thought that 3 variants of Kunitz type trypsin inhibitor(SBTi A 2) existed in soybean seed storage protein.Three of codominant alleles Ti a,Ti b and Ti c were identified to decode these SBTi A 2 inhibitors and the amino acid sequences of them were determined,of which one or more different amino acid were found.Ti d was a new variant allele of SBTi A 2 discovered after analyzing more than 15 000 samples of soybean seed in China.In order to study the structure features of Ti d protein,the amino acid sequence of this protein was deduced from its coding region which was amplified by PCR from soybean genomic DNA and sequenced.By comparison with Ti a protein,two different amino acid residue were found between Ti a and Ti d proteins.One was an extra Ala inserted in the signal peptide of Ti d,with 8 residues from N terminal,and the other existed in the mature protein,with Glu 69 in Ti a protein turned into Lys 69 in Ti d protein.The amino acid sequence of Ti d mature protein was also different from those of Ti a and Ti b.
