PLANT PHYSIOLOGY , Vol 104, Issue 1 119-125, Copyright © 1994 by American Society of Plant Biologists
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MOLECULAR BIOLOGY AND GENE REGULATION |
Expression of Erwinia uredovora Phytoene Desaturase in Synechococcus PCC7942 Leading to Resistance against a Bleaching Herbicide
U. Windhovel, B. Geiges, G. Sandmann and P. Boger
Lehrstuhl fur Physiologie und Biochemie der Pflanzen, Universitat Konstanz, D-78434 Konstanz, Germany
The gene coding for phytoene desaturase of the bacterium Erwinia uredovora
(crtI) was inserted into the chromosome of the cyanobacterium Synechococcus
PCC7942 strain R2-PIM8. For expression of crtI in the heterologous host,
two constructs with different promoters were introduced into Synechococcus.
In the first, crtI was fused to the 5[prime] region of the psbA gene of the
xanthophycean microalga Bumilleriopsis filiformis. The second construct
carried crtI inserted downstream of the neomycin phosphotransferase II gene
(nptII) from the transposon Tn5. Expression of crtI under the control of
the respective promoter was shown by immunodetection of the gene product.
The functionality of the heterologously expressed phytoene desaturase CRTI
in the transformants was demonstrated by enzymic assays. The transformants
acquired very strong resistance toward the bleaching herbicide norflurazon.
