The Chl a Carboxylic Biosynthetic Routes: (Photo) Conversion of Protochlorophyllides (Pchlides) a to Chlorophyllide (Chlide) a - Chlorophyll Biosynthesis and Technological Applications - page 243

Fig. 9.5 Photoconversion of MV Pchlide a to MV Chlide a in DMV-LDV-LDMV plants via
routes 10, 0 0 and 12 (Adapted from Fig. 6.4 of Chap. 6 )
9.4.5 Formation of MV Chlide a by Vinyl Reduction of DV
Chlide a via Routes 4 and 8 in DDV-LDV-LDDV Plants
In DDV-LDV-LDDV etiolated tissues, or in green DDV-LDV-LDDV tissues
during the initial dark-cycles of the photoperiod, MV Chlide a is formed by
reduction of the vinyl group of DV Chlide a at position 4 of the macrocycle to
ethyl via routes 4 and 8 (Fig. 9.6 ). The reduction of the vinyl group of DV Chlide
a to ethyl is catalyzed in darkness and in the light by a very potent enzyme, 4VCR
(Duggan and Rebeiz 1982b ; Parham and Rebeiz 1992 ). 4VCR is a fast acting