Evolution of the glutamine synthetase gene, one of the oldest existing and functioning genes.

• DOI: 10.1073/pnas.90.7.3009
• Publication Date: 2006-05-31T12:42:11Z
• Authors: Y Kumada; D R Benson; D Hillemann; T J Hosted; D A Rochefort; C J Thompson; W Wohlleben; Y Tateno
• Keywords: Molecular evolution; Nuclear gene

We performed molecular phylogenetic analyses of glutamine synthetase (GS) genes in order to investigate their evolutionary history. The were done on 30 DNA sequences the GS gene which included both prokaryotes and eukaryotes. Two types are known at present: GSI found so far only GSII Our study has shown that two produced by a duplication preceded, perhaps > 1000 million years, divergence eukaryotes prokaryotes. results consistent with facts (i) is key enzyme nitrogen metabolism all extant life forms (ii) oldest biological fossils date back 3800 years. Thus, we suggest one existing functioning history evolution should also exist Furthermore, our may stimulate investigation "preprokaryotes," mean organisms existed during era between origin