Extracellular production of the engineered thermostable protease pernisine from Aeropyrum pernix K1 in Streptomyces rimosus

Table 2 Residual protease activities of recombinant pernisine in the presence of the protease inhibitors

Addition	Concentration	Residual proteinase activity at 1 mM CaCl₂ (%)
Addition	Concentration	Present study	Recombinant pernisine in E. coli^a	Native pernisine^b
None	–	100.0 ± 5.3	100.0 ± 1.7	100.0
EDTA	1	78.6 ± 6.7	92.8 ± 0.6	93.5
	5	0.5 ± 4.7	2.1 ± 0.1	0.5
EGTA	1	85.7 ± 5.4	90.5 ± 5.5	91.2
	5	6.0 ± 1.0	8.2 ± 1.0	1.4
PMSF	1	39.5 ± 4.4	6.1 ± 0.8	6.9
	10	21.0 ± 3.4	0.9 ± 0.5	2.8
IAA	1	111.1 ± 8.2	69.1 ± 6.5	ND
	10	99.6 ± 5.4	89.6 ± 2.0	91.7

ND no data, EDTA ethylenediaminetetraacetic acid, EGTA ethylene glycol-bis(b-aminoethyl ether)-N,N,N,N-tetraacetic acid, PMSF phenylmethylsulphonyl fluoride, IAA iodoacetamide
^aŠnajder et al. [7]
^bŠnajder et al. [6]

ISSN: 1475-2859