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 1

Flow sheet purification of the SAPV enzyme from Virgibacillus natechei strain FarD^T.

Purification step^a	Total activity (units)^b ×10^3	Total protein (mg)^b,c	Specific activity (U/mg of protein)^b	Purification yields (%)	Purification factor (fold)
Crude extract	8,000 ± 120	3,624 ± 71.3	2,207	100	1
(NH4)2SO4 fractionation (20–80%)-dialysis	6,640 ± 54	1,382 ± 41.2	4,804	83	2.17
HPLC (ZORBAX PSM 300 HPSEC)	4,864 ± 22	65.15 ± 0.83	74,652	60.8	33.82

^aExperiments were conducted three times, and ± standard errors are reported. ^bOne unit of peptidase activity was defined as the amount of enzyme required to release 1 µg tyrosine per minute under the experimental conditions used. ^cAmounts of protein were estimated by the method of Bradford [27].