The Chlorophyll Biosynthetic Heterogeneity and Chloroplast Bioengineering - Chlorophyll Biosynthesis and Technological Applications - page 346

16.6.4 Epilogue
Future research dealing with the bioengineering of smaller PSU sizes will have to
use as a working hypothesis the MBP-sublocation Chl a -thylakoid protein biosyn-
thesis model. First the researcher will have to deal with the determination of which
Chl biosynthetic routes gives rise to PSI, PSII and LHCII Chl-protein complexes.
The greening process may then be manipulated to bioengineer genetically modified
plants with a smaller PSU, i.e. with more PSU units having fewer antenna Chl per
unit thylakoid area. Nevertheless this type of agriculture using genetically modified
plants with smaller PSU sizes and higher photosynthetic conversion efficiencies
will still be at the mercy of extrinsic factors and weather uncertainties.
In our opinion the ultimate agriculture of the future should consist of bioreactors
populated with bioengineered, highly efficient photosynthetic membranes, with a
small PSU size and operating at efficiencies that approach the 12 % maximal
theoretical efficiency of the PETS that may be observed under white light, or the
27 % maximal theoretical efficiency that may be achieved under red light. Such
conditions may be set up during space travel, in large space stations, or in human
colonies established on the moon or on Mars (Rebeiz et al. 1982 ). The photosyn-
thetic product may well be a short chain carbohydrate such as glycerol that can be
converted into food fiber and energy.
In the meanwhile, let us not forget that a journey of 10,000 miles starts with
the first step.
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