Five structural genes coding for the reaction center (RC) L, M, and H subunits and the two light-harvesting (LH) I polypeptides, B870α and B870β, have been mapped on two restriction fragments from the R-prime plasmid pRPS404. It has been recently shown that enhanced near-infrared fluorescence mutants of Rhodopseudomonas capsulata typically lack RC or LH I polypeptides and that these lesions are marker-rescued by two restriction fragments from the R-prime plasmid: the 7.5-kilobase-pair Eco RI F fragment and the 4.75-kilobase-pair Bam HI C- Eco RI fragment. We have now determined the nucleotide sequence of two restriction fragments and have found that the Bam HI C- Eco RI B fragment carries the structural genes for the RC L and M subunits and both LH I polypeptides. Forty kilobase pairs away from this locus, the Bam HI F fragment (within the Eco RI F fragment) carries the RC H subunit. The structural genes on the Bam HI C- Eco RI B fragment are probably transcribed as part of a polycistronic mRNA. All of the structural genes begin with a consensus Shine-Dalgarno sequence and separate AUG start codons, indicating that the structural polypeptides are not cleaved from larger precursor polypeptides.

Youvan, D. C., Alberti, M., Begusch, H., Bylina, E. J., & Hearst, J. E. (1984). Reaction center and light-harvesting I genes from Rhodopseudomonas capsulata. Proceedings of the National Academy of Sciences, 81(1), 189–192.