Presence of an N-terminal presequence in the PsaI protein of the photosystem I complex in the filamentous cyanobacterium Anabaena variabilis ATCC 29413.
The psaI gene encoding the 5.2 kDa protein component (PsaI) of the photosystem I complex was cloned from the cyanobacterium Anabaena 29413. The gene is present in single copy in this cyanobacterial genome. The nucleotide sequence of a 500 bp region of the cloned DNA revealed the presence of an open reading frame encoding a 46 amino acid long polypeptide. The N-terminal 11 residues are absent in the mature polypeptide and thus represents the first identified cleavable presequence on the PsaI protein. We suggest that this presequence directs the N-terminus of the protein to the thylakoid lumen.
Sonoike
K
K
Department of Biology, Washington University, St. Louis, MO 63130-4899.
Ikeuchi
M
M
Pakrasi
H B
HB
D000595:Amino Acid Sequence; D017033:Anabaena / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics*; D045331:Photosystem I Protein Complex; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; C078702:photosystem I, PsaI subunit