Comparative Analyses of Exoproteinases Produced by Three Phytopathogenic Microorganisms

Table 4

Effect of synthetic inhibitors on the activity of exoproteinases secreted by P. infestans, F. culmorum, and R. solani (concentration of DIFP was 0.2 mM, EDTA was 4.0 mM, and the other inhibitors were 1.0 mM). Activity without inhibitors was taken as 100%.

Inhibitor	Substrate
	P. infestans, % of residual activity			R. solani, % of residual activity			F. culmorum, % of residual activity
	Azocasein	BAPNA	Z-AALPNA	Azocasein	BAPNA	Z-AALPNA	Azocasein	BAPNA	Z-AALPNA
DIFP	na*	42.0 ± 1.4	na	na	na	na	na	na	na
PMSF	100 ± 0.1	100 ± 0.2	0 ± 0.0	61.0 ± 2.4	96.0 ± 3.1	0 ± 0.0	35.0 ± 0.8	17.4 ± 0.6	78.0 ± 2.1
CMKTL	na	4.0 ± 0.2	95.0 ± 3.5	95.0 ± 3.8	70.0 ± 1.9	72.0 ± 2.5	84.0 ± 3.1	50.0 ± 1.8	52.0 ± 2.4
CMKTP	na	52.0 ± 2.1	91.0 ± 2.9	82.0 ± 3.1	84.0 ± 2.8	85.0 ± 4.1	80.0 ± 3.8	46.0 ± 2.0	100 ± 0.1
EDTA	20.3 ± 0.5	41.0 ± 1.6	0 ± 0.0	89.0 ± 3.6	93.0 ± 3.5	90.0 ± 3.6	112.0 ± 3.9	99.0 ± 0.6	99.0 ± 0.4
PCMB	95.1 ± 3.2	69.0 ± 2.7	100 ± 0.1	76.0 ± 2.7	95.0 ± 3.2	80.0 ± 2.6	61.0 ± 1.7	100 ± 0.1	100 ± 0.2
IAA	100 ± 0.1	90.1 ± 3.8	100 ± 0.2	100 ± 0.1	93.0 ± 2.9	100 ± 0.1	97.0 ± 2.1	101.6 ± 0.8	101.2 ± 0.9
DTT	100 ± 0.1	93.4 ± 4.2	84.2 ± 2.8	66.0 ± 2.3	129.1 ± 4.4	91.0 ± 4.0	82.0 ± 2.5	98.4 ± 1.0	99.2 ± 0.5
Mercuric chloride	65.4 ± 2.4	57.2 ± 2.2	27.4 ± 1.3	79.0 ± 3.0	95.0 ± 2.5	89.0 ± 2.9	53.0 ± 2.0	34.0 ± 1.3	55.2 ± 2.2

*na—not assayed.