ISSN:
1432-2048
Keywords:
Chlorophyll biosynthesis
;
Nicotiana (chlorophyll biosynthesis)
;
Geranylgeranyl phosphate
;
Phytol
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The incorporation of [1-3H] geranylgeranyl diphosphate (GGPP), [1-3H] geranylgeranyl monophosphate (GGMP) and [U-14C] phytyl diphosphate (PhPP) into chlorophylls a and b in growing tobacco cell cultures was investigated. The substrates were effectively incorporated into chlorophylls a and b, 3.2% of the total activity of applied GGPP or GGMP and 12.4% of the total activity of applied PhPP being found in chlorophylls a and b after 24 h incubation. The radioactivity was found in phytyl chlorophyllide through-out which means effective hydrogenation of the alcohol moiety in the case of GGPP and GGMP. With increasing substrate concentration, the specific radioactivity of chlorophyll increased up to a saturation level which was reached either at 20–40 μM PhPP or at 60 μM GGPP and GGMP. The specific radioactivity of the chlorophyll formed during the 24-h incubation period was the same as that of the applied substrate at saturating substrate concentration. The specific radioactivity of chlorophyll a was higher than that of chlorophyll b only in the case of PhPP.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00397442
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