13 

 Cofactor specificity. Rot he et al . (67) separated two 

 SDH (NADP*) activities from pea seedlings on a Celite 545 

 column with an ammonium sulfate gradient. Whether DQT 

 activity coeluted with one or both of the SDH activities was 

 not examined. Shikimate dehydrogenase was shown to be 

 located in the stroma of spinach chloroplasts and was 

 partially purified (30). Mousdale et al . (61) purified a 

 bifunctional DQT/SDH (NADP* specific) from pea seedling 

 chloroplasts and also showed by chromatofocusing that there 

 were two chloroplast isoenzymes and one unstable isoenzyme, 

 probably located in the cytosol . Two forms of nondissoc- 

 iable DQT/SDH (NADP") activities and one of QDH (NAD^) were 

 found in Phaseolus mungo seedlings by Minamikawa (58) . 

 Koshiba (49) also found two forms of DQT/SDH (NADP*) 

 activities from Phaseolus mungo seedlings. In 1988, Ogawa 

 and Tateoka (64) reported one SDH (NADP*) specific activity 

 and two SDH (NAD*) specific activities (DQT apparently was 

 not assayed in these fractions) from Phaseolus mungo. This 

 is the first description of NAD* specific SDH activities and 

 is surprising since the same methodology for separation was 

 used by the three groups and each checked for specificity of 

 cof actors. A recent study of QDH in Phaseolus mungo by Kang 

 and Scheibe (44) found that the enzyme could use NADP* as 

 well as NAD*. When SHK was added to the reaction mix 

 containing quinic acid and NAD*, some inhibition was found. 

 Apparently SHK was not tried as a substrate for QDH. If QDH 



1^ 

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