Abstract
The operon (atp2) encoding the β and ε{lunate} subunits of F-ATPase from Chlorobium limicola was cloned and sequenced. In contrast with purple bacteria these genes are arranged in a separate operon similar to the cyanobacteria. The operon terminates with a pronounced stem-loop structure. About 0.8 kb upstream of the β subunit a gene encoding the enzyme phosphoenolpyruvate carboxykinase was identified. This gene is transcribed in the opposite direction of the atp2 operon and also ends with a stem-loop structure. These genes of green bacteria are among the first to be sequenced, and therefore the genetic distance between these genes and corresponding genes from other bacteria and eukaryotes was studied. Even though the operon structure resembles that of cyanobacteria, the evolutionary tree compiled from these data places the chlorobium gene close to purple bacteria. Chlorobium limicola β and ε{lunate} subunits complemented Escherichia coli mutants defective in the corresponding subunits, indicating that the hybrid enzyme formed from subunits of the two bacteria is active in ATP synthesis.
| Original language | English |
|---|---|
| Pages (from-to) | 267-273 |
| Number of pages | 7 |
| Journal | BBA - Gene Structure and Expression |
| Volume | 1172 |
| Issue number | 3 |
| DOIs | |
| State | Published - 20 Mar 1993 |
| Externally published | Yes |
Keywords
- (E. coli)
- Chlorobium
- F-ATPase
- Hybrid enzyme
- Operon