116 



Table 6-1, S-Protein Antibody Effect on N. silvestris 

 and E. coli^ extracts. 



Crude Extracts (nmol min"^) 



Antibody (/il) Antigen iJiT) E~. coli W. silvestris 



25 2.73 0.364 



25 25 2.72 0.031 



50 25 2.73 0.016 



^Antibody (0.16mg ml'^) , crude extracts ( . 019rag ml"^) 

 and buffer were added at a total volume of 100/il, 

 incubated at 3 7°C for 10 min and microfuged before 

 assay at 24°C. 



Discussion 

 The two bifunctional S-proteins of N. silvestris, were 

 each precipitated by antibody made to purified SP-I as seen 

 by precipitant bands on" Ouchterlony" plates, and by loss of 

 activity following incubation of antibody and antigen. 

 There was no loss of activity for SDH and DQT from E. coli 

 crude extracts. These results suggested that the antibody 

 would be a suitable probe for selection of cDNA encoding for 

 the DQT/SDH bifunctional protein of higher plants after 

 treatment with an E. coli lysate to remove background 

 contaminants. Results from a Western blot indicate the 

 possibility of multiple SDH activities in crude extracts of 

 N. silvestris. From six to seven bands may be visible on the 

 Western blot. There are from three to six bands that are 

 visible when an activity stain specific for SDH is applied 

 to PAGE containing crude extract from the same protein 

 sample. The possibility of a pentafunctional arom protein 



