FIGURE 4.

Shown is the ulvan-containing agarose plate stained by 0.05% ruthenium red aqueous solution revealing the enzymatic degradation of ulvan by the purified 30- (A) and 46-kDa (B) proteins and the recombinant catalytic module (C). As a control, an extract of E. coli carrying the expression plasmid without the insert was also tested on the agar plate (D).