The carboxy-terminal extension of the D1-precursor protein is dispensable for a functional photosystem II complex in Chlamydomonas reinhardtii.
The D1-precursor protein of the photosystem II reaction centre contains a carboxy-terminal extension whose proteolytic removal is necessary for oxygen-evolving activity. To address the question of the role of the carboxy-terminal extension in the green alga Chlamydomonas reinhardtii, we truncated D1 by converting codon Ser345 of the psbA gene into a stop codon. Particle gun transformation of an in vitro modified psbA gene fragment also carrying mutations conferring herbicide resistance yielded a homoplasmic transformant containing the stop codon. Since oxygen evolution capacity is not affected in this mutant as compared with herbicide-resistant control cells, the carboxy-terminal extension is dispensable for a functional photosystem II complex under normal growth conditions.
Schrader
S
S
Lehrstuhl für Biochemie der Pflanzen, Ruhr-Universität Bochum, Germany.
Johanningmeier
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U
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism*; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D003062:Codon / Q000235:genetics; D005091:Exons; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009838:Oligodeoxyribonucleotides; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics* / Q000378:metabolism*; D045332:Photosystem II Protein Complex; D015183:Restriction Mapping
D003062:Codon; D009838:Oligodeoxyribonucleotides; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex