Nucleotide sequence of cDNA clones encoding the complete ‘23 kDa’ and ‘16 kDa’ precursor proteins associated with the photosynthetic oxygen‐evolving complex from spinach

Abstract

We present the nucleotide sequences and derived amino acid sequences of cDNAs that encode the complete precursors of the extrinsic ‘23 kDa’ and ‘16 kDa’ polypeptides associated with the photosynthetic oxygen‐evolving complex from spinach. The luminal proteins consist of 267/186 (precursor/mature 23 kDa protein) and 232/149 (16 kDa polypeptide) amino acid residues corresponding to molecular masses of 28.5/20.2 and 24.9/16.5 kDa, respectively. Secondary structure predictions disclose epitopes that are potential candidates for two‐step processing of the precursors during import and intraorganelle routing as well as for calcium sequestering, chloride binding and subunit/subunit interaction.