Gene re-arrangement and fusion in Mycoplasma gallisepticum thyA-nrdFEI locus.
Sequencing of Mycoplasma gallisepticum genome fragment containing thymidylate synthase and ribonucleotide reductase gene clusters reveals both its unusual organization and gene content. Sequence analysis indicates the presence of a gene whose product can be considered as a fusion of two full size proteins: the N-terminal part shows significant similarity to mycoplasmal dihydrofolate reductases, while the C-terminal part of the polypeptide chain shows significant similarity to eukaryotic deoxycytidylate deaminase. Phylogenetic analysis has suggested that the C-terminal part of the M. gallisepticum fusion gene and eukaryotic deoxycytidylate deaminase genes are xenologous. No chromosomal regions encoding peptides similar to the C-terminal part of this fusion protein were found in completely sequenced genomes of Mycoplasma genitalium and Mycoplasma pneumoniae. Genes for ribonucleoside diphosphate reductase alpha chain (nrdE), NrdI protein (nrdI), and ribonucleoside diphosphate reductase beta chain (nrdF) have an opposite direction of transcription with respect to genes for thymidylate synthase (thyA), and dihydrofolate reductase-deoxycytidylate deaminase fusion protein.
Skamrov
A
A
National Cardiology Research Center, Ministry of Health of the Russian Federation, 3rd Cherepkovskaya Str. 15A, 121552 Moscow, Russia. skamrov@cardio.ru
Feoktistova
E
E
Goldman
M
M
Beabealashvilli
R
R
D000595:Amino Acid Sequence; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins; D002876:Chromosomes, Bacterial; D019143:Evolution, Molecular; D015321:Gene Rearrangement; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D012262:Ribonucleoside Diphosphate Reductase / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013940:Thymidylate Synthase / Q000235:genetics*
D001426:Bacterial Proteins; C431606:NrdI protein, Mycoplasma gallisepticum; D012262:Ribonucleoside Diphosphate Reductase; D013940:Thymidylate Synthase