Table II.

Enzyme activity of cell wall degrading enzymes expressed in E. coli and chloroplast

Enzyme	pH	°C	Substrate	Enzyme activity (units/mg) in crude total soluble protein		Activity of transplastomic over E.coli (fold)
Enzyme	pH	°C	Substrate	E.coli	Transplastomic	Activity of transplastomic over E.coli (fold)
CelD	5.2	60 °C	CMC (2%)	349 ±36	493 (±21)	1.41
EG1	5.2	50 °C	CMC (2%)	28 ±7	339 (±12)	12.10
CelO	5.2	60 °C	β-D-glucan (1%)	18 ±2	442 (±19)	24.55
Bgl1	5.2	50 °C	p-nitrophenyl-β-D-glucopyranoside (4mM)	2 ±0.02	14 (±2)	7.0
Xyn2	5.2	50 °C	Oat spelt xylan (1%)	89 ±3	421 ±9	4.73
PelB	6 & 8	40 °C	Polygactouronic acid (0.25%)	2.17 ±0.2	2.42 ±0.1	1.12
PelD	6 & 8	40 °C	Polygactouronic acid (0.25%)	2.09 ±0.3	2.31 ±0.4	1.10
PelA	6 & 8	40 °C	Polygactouronic acid (0.25%)	2.50 ±0.5	2.81 ±0.9	1.12
Cutinase	8.0	30 °C	p-nitrophenyl butyrate (0.03%)	24 ±4	15 ±4	<0.625
SwoI	Swelling of cotton fiber was observed with E. coli and chloroplast-derived crude extract as described earlier (Saloheimo et al., 2002).
Axe1	Color change with E. coli enzyme extract was observed using 1 mM α-naphthyl acetate as described earlier (Poutanen and Sundberg, 1988)

Enzyme assays were done in triplicates and standard errors were calculated. Untransformed tobacco leaves and E.coli did not show detectable level of hydrolysis of any of the above substrates under conditions described in the materials and method.: