Mechanism and Energetics of Protein Transport Across the Thylakoid Membrane
The assembly of the photosynthetic machinery in the higher plant chloroplasts is a complex process, in part because the component proteins are synthesised by two distinct genetic systems. Approximately half of the known thylakoidal proteins are synthesised within the organelle, whereas the remainder are imported after synthesis in the cytosol. The biogenesis of the latter group of proteins has attracted considerable interest in recent years, since these proteins must cross both of the envelope membranes and the soluble stromal phase to reach the thylakoid membrane. Of particular complexity is the import of hydrophilic thylakoid lumen proteins, which must in addition traverse the thylakoid membrane to reach their site of function.
KeywordsChlorophyll Codon Polypeptide Methionine Cytosol
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