Identification of a New Serine Alkaline Peptidase from the Moderately Halophilic Virgibacillus natechei sp. nov., Strain FarD^T and its Application as Bioadditive for Peptide Synthesis and Laundry Detergent Formulations

Table 5

Kinetic parameters of purified peptidases: rSAPV, SPVP, Thermolysin type X, Alcalase 2.4 L FG, and Bioprotease N100L for hydrolysis of natural protein (casein) and synthetic peptide (Suc-F-A-P-F-pNA).

Substrate	Enzyme	Km (mM)^a	Vmax (U/mg)^a	kcat (min^−1)	kcat/Km (min^−1 mM^−1)
Casein	rSAPV	0.313 ± 0.01	74,652 ± 570	49,768	159,003
	SPVP	0.455 ± 0.03	41,255 ± 425	27,503	60,446
	Thermolysin type X	0.738 ± 0.05	17.126 ± 150	11,417	15,470
	Alcalase 2.4 L FG	0.765 ± 0.06	22,915 ± 285	15,277	19,970
	Bioprotease N100L	0.800 ± 0.07	19,500 ± 113	13,000	16,250
Suc-F-A-A-F-pNA	rSAPV	0.600 ± 0.04	155,400 ± 990	103,600	172,667
	SPVP	0.700 ± 0.05	95,833 ± 596	63,889	91,270
	Thermolysin type X	1.100 ± 0.09	30,700 ± 392	20,467	18,606
	Alcalase 2.4 L FG	1.410 ± 0.15	52,950 ± 495	35,300	25,035
	Bioprotease N100L	1.560 ± 0.21	43,900 ± 490	29,267	18,761

^aValues represent the means of three replicates, and ± standard errors are reported.