Joined: Dec. 2002
|Mol Biol Evol 1990 Sep;7(5):399-406|
Evolution of isopenicillin N synthase genes may have involved horizontal gene transfer.
Landan G, Cohen G, Aharonowitz Y, Shuali Y, Graur D, Shiffman D.
Interdisciplinary Program for Fostering Excellence, Tel Aviv University, Ramat Aviv, Israel.
The isopenicillin N synthase genes from three fungal species, three Gram-positive species, and one Gram-negative bacterial species share an unusually high sequence similarity. A phylogenetic analysis was carried out to determine which type of evolutionary scenario best accounts for this similarity. The most plausible scenario is one in which a horizontal gene-transfer event, from the prokaryotes to the eukaryotes, occurred at a time close to the divergence between the Gram-positive and the Gram-negative bacteria.
|Proc R Soc Lond B Biol Sci 1990 Sep 22;241(1302):164-9 |
Sequences of isopenicillin N synthetase genes suggest horizontal gene transfer from prokaryotes to eukaryotes.
Penalva MA, Moya A, Dopazo J, Ramon D.
Centro de Investigaciones Biologicas del C.S.I.C., Madrid, Spain.
Evolutionary distances between bacterial and fungal isopenicillin N synthetase (IPNS) genes have been compared to distances between the corresponding 5S rRNA genes. The presence of sequences homologous to the IPNS gene has been examined in DNAs from representative prokaryotic organisms and Ascomycotina. The results of both analyses strongly support two different events of horizontal transfer of the IPNS gene from bacteria to filamentous fungi. This is the first example of such a type of transfer from prokaryotes to eukaryotes.
|J Mol Evol 1996 May;42(5):537-42|
Phylogenetic analysis of the isopenicillin-N-synthetase horizontal gene transfer.
Buades C, Moya A.
Departamento de Genetica, Facultad de Biologia, Universidad de Valencia, Spain.
A phylogenetic study of the isopenicillin-N-synthetase (IPNS) gene sequence from prokaryotic and lower eukaryotic producers of beta-lactam antibiotics by means of a maximum-likelihood approach has been carried out. After performing an extensive search, rather than invoking a global molecular clock, the results obtained are best explained by a model with three rates of evolution. Grouped in decreasing order, these correspond to A. nidulans and then to the rest of the eukaryotes and prokaryotes, respectively. The estimated branching date between prokaryotic and fungal IPNS sequences (852 +/- 106 MY) strongly supports the hypothesis that the IPNS gene was horizontally transferred from bacterial beta-lactam producers to filamentous fungi.
For more bibliography on IPNS, see: http://metallo.scripps.edu/PROMISE/IPNS.html among others.