Article

Impact of genome reduction on bacterial metabolism and its regulation.

Centre for Genomic Regulation (CRG) and Universitat Pompeu Fabra, Avenida Dr. Aiguader 88, 08003 Barcelona, Spain.
Science (Impact Factor: 31.48). 11/2009; 326(5957):1263-8. DOI: 10.1126/science.1177263
Source: PubMed

ABSTRACT To understand basic principles of bacterial metabolism organization and regulation, but also the impact of genome size, we systematically studied one of the smallest bacteria, Mycoplasma pneumoniae. A manually curated metabolic network of 189 reactions catalyzed by 129 enzymes allowed the design of a defined, minimal medium with 19 essential nutrients. More than 1300 growth curves were recorded in the presence of various nutrient concentrations. Measurements of biomass indicators, metabolites, and 13C-glucose experiments provided information on directionality, fluxes, and energetics; integration with transcription profiling enabled the global analysis of metabolic regulation. Compared with more complex bacteria, the M. pneumoniae metabolic network has a more linear topology and contains a higher fraction of multifunctional enzymes; general features such as metabolite concentrations, cellular energetics, adaptability, and global gene expression responses are similar, however.

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