ISSN:
1573-5028
Keywords:
algae
;
endosymbiosis
;
evolution
;
plastidial DNA
;
Rubisco operon
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The rbcS gene coding for the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) of the brown alga Pylaiella littoralis is located within the plastid genome and is transcribed as a single polycistronic mRNA with the gene for the large subunit of Rubisco, rbcL. The structure of the Rubisco operon from P. littoralis was determined. Molecular phylogenies for rbcS and rbcL with a wide range of prokaryotes and eukaryotes were constructed which are congruent with recent evidence for polyphyletic plastid origins. Both rbcL and rbcS of the β-purple bacterium Alcaligenes eutrophus clearly cluster with the rhodophyte and chromophyte proteins. The data suggest that the Rubisco operons of red algal and chromophytic plastids derive from β-purple eubacterial antecedents, rather than the cyanobacterial lineage of eubacteria from which other of their genes derive. This implies a lateral transfer of Rubisco genes from β-purple eubacterial ancestors to the cyanobacterial ancestor of rhodophyte and chromophyte plastids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00037066