Table of Contents
International Journal of Evolutionary Biology
Volume 2012, Article ID 745931, 6 pages
http://dx.doi.org/10.1155/2012/745931
Research Article

Evolution of Lysine Biosynthesis in the Phylum Deinococcus-Thermus

1Agricultural Bioinformatics Research Unit, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
2Biotechnology Research Center, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan

Received 28 January 2012; Accepted 17 February 2012

Academic Editor: Kenro Oshima

Copyright © 2012 Hiromi Nishida and Makoto Nishiyama. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Thermus thermophilus biosynthesizes lysine through the α-aminoadipate (AAA) pathway: this observation was the first discovery of lysine biosynthesis through the AAA pathway in archaea and bacteria. Genes homologous to the T. thermophilus lysine biosynthetic genes are widely distributed in bacteria of the Deinococcus-Thermus phylum. Our phylogenetic analyses strongly suggest that a common ancestor of the Deinococcus-Thermus phylum had the ancestral genes for bacterial lysine biosynthesis through the AAA pathway. In addition, our findings suggest that the ancestor lacked genes for lysine biosynthesis through the diaminopimelate (DAP) pathway. Interestingly, Deinococcus proteolyticus does not have the genes for lysine biosynthesis through the AAA pathway but does have the genes for lysine biosynthesis through the DAP pathway. Phylogenetic analyses of D. proteolyticus lysine biosynthetic genes showed that the key gene cluster for the DAP pathway was transferred horizontally from a phylogenetically distant organism.