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Proteobacterial histidine-biosynthetic pathways are paraphyletic.
- Source :
-
Journal of molecular evolution [J Mol Evol] 2000 Apr; Vol. 50 (4), pp. 339-47. - Publication Year :
- 2000
-
Abstract
- In Lactococcus lactis there is a protein, HisZ, in the histidine-biosynthetic operon that exhibits significant sequence identity with histidyl-tRNA synthetase (HisRS) but does not aminoacylate tRNA. HisRS homologs that, like HisZ, cannot aminoacylate tRNA are represented in a highly divergent set of bacteria (including an aquificale, cyanobacteria, firmicutes, and proteobacteria), yet are missing from other bacteria, including mycrobacteria and certain proteobacteria. Phylogenetic analysis of the HisRS and HisRS-like family suggests that the HisZ proteins form a monophyletic group that attaches outside the predominant bacterial HisRS clade. These observations are consistent with a model in which the absences of HisZ from bacteria are due to its loss during evolution. It has recently been shown that HisZ from L. lactis binds to the ATP-PRPP transferase (HisG) and that both HisZ and HisG are required for catalyzing the first reaction in histidine biosynthesis. Phylogenetic analysis of HisG sequences shows conclusively that proteobacterial HisG and histidinol dehydrogenase (HisD) sequences are paraphyletic and that the partition of the Proteobacteria associated with the presence/absence of HisZ corresponds to that based on HisG and HisD paraphyly. Our results suggest that horizontal gene transfer played an important role in the evolution of the regulation of histidine biosynthesis.
- Subjects :
- Amino Acid Sequence
Amino Acyl-tRNA Synthetases genetics
Bacterial Proteins genetics
Evolution, Molecular
Gene Transfer, Horizontal
Histidine-tRNA Ligase chemistry
Molecular Sequence Data
Monosaccharide Transport Proteins genetics
Operon
Proteobacteria genetics
Recombination, Genetic
Sequence Alignment
Alcohol Oxidoreductases
Histidine biosynthesis
Histidine-tRNA Ligase genetics
Phylogeny
Proteobacteria classification
Proteobacteria enzymology
Subjects
Details
- Language :
- English
- ISSN :
- 0022-2844
- Volume :
- 50
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Journal of molecular evolution
- Publication Type :
- Academic Journal
- Accession number :
- 10795825
- Full Text :
- https://doi.org/10.1007/s002399910037