Table I.

Comparison of APS reductase activity among different plant species

Algal Species	APS Reductase Activity in Crude Cell Lysates
	× 10−3 units mg−1
Arabidopsis* (young leaves)	≤1.3
Indian mustard* (young leaves)	≤1
E. intestinalis	4–20
Tetraselmis sp.	100–500
D. salina*	50–100
T. weissflogii	200
T. oceanica	80–130
I. galbana	100–250
E. huxleyi	100–400
H. triquetra	0.5–5

Arabidopsis and all phytoplankton species were laboratory-grown materials, whereas E. intestinalis were collected from the field (see “Materials and Methods”). Species with no capacity of DMSP synthesis were indicated with an asterisk. The range of activity was determined from samples collected at different growth stage, therefore reflecting the biological variations of the activity in different species.