FIGURE 2.

Cyanide metabolizing enzymes (except rhodanese) in cassava have higher activities in roots compared to leaves. (A) Activities of rhodanese (in μmol thiocyanate/mg protein/minute) in tuberous roots and leaves of 8 months old cassava plants grown under glasshouse conditions. (B) CAS activity (in μmol hydrogen sulfide (H₂S) per mg protein per minute) in 8 months old cassava (C). Nitrilase (cyanoalanine hydratase) enzyme activities (in μmol ammonia/mg protein/min) in roots and leaves of in vitro cassava plants at 5 weeks. (D) Analysis of nitrate reductase activity (μmol nitrite/mg protein/min) in wild-type (WT) and transgenic low cyanogen (Cab1-1, Cab1-2, and Cab1-3; Siritunga and Sayre, 2003) lines. The assay was conducted on 5 weeks old in vitro plants. The results of all experiments are the averages from biological four trials. Statistical analysis was done by one-way ANOVA with Dunnett’s Multiple Comparison Test. Asterisks indicate significant difference at P ≤ 0.05.