Isolation, characterization and heterologous expression of a novel chitosanase from Janthinobacterium sp. strain 4239

Table 1 Cellular distribution of chitosanase activity

	Chitosanase specific activity^a units·OD₆₀₀^-1·ml^-1			G6PD activity^b %
Strains	CYT	PER	MED	PER/CYT
Janthinobacterium 4239	0.016	0.007	0.035	-
E. coli BMS172	17.8	20.3	1.25	62
E. coli MGJ1042 (control)	0.002	0	0	23

^a Specific chitosanase activity is presented as units (μmol/min) of reducing ends released per milliliter of cells with OD₆₀₀ = 1 (U·OD₆₀₀^-1·ml^-1). CYT, cytoplasmic extract. PER, periplasmic extract. MED, culture medium obtained after centrifugation. ^b Glucose-6-phosphate dehydrogenase (G6PD) is a cytoplasmic marker indicating the degree of cell lysis. Periplasmic extract of Janthinobacterium sp. strain 4239 showed no G6PD activity.

ISSN: 1475-2859