Table V.

Maximum activity of CGS in lupin seeds throughout storage protein accumulation

Lupin Genotype	CGS Activity at Mid-Maturation	Total Maximum CGS Activity during Seed Maturation	Total Met in Mature Seed
	nmol product min−1 mg−1 protein	μmol product g dry wt−1	μmol g dry wt
Control	0.15	119	14.4
Tg	0.25	198	26.8

Storage proteins accumulated between 20 and 40 DAF in narrow leaf lupin seeds grown in sand/ perlite and watered with high sulfur nutrient (Tabe and Droux, 2001). It was assumed that the CGS activity measured in whole developing seeds at mid-maturation (30 DAF) represented a mean activity over this period. A theoretical maximum amount of product that could be generated by the enzyme over the entire period was calculated by multiplying the maximum enzyme activity by time. It was assumed that the enzyme operated at maximum activity for 12 h a day, and seed flours contained an average of 55 mg low salt extractable protein g⁻¹ dry wt. One mol of cystathionine gives rise to 1 mol of Met; therefore mol of product calculated in column 2 can be compared directly with mol of Met in column 3.