About ~ Mycoplasma Project
Project: Systems Biology of Mycoplasma pneumoniae
The minimal gene set to sustain life

During the past years, a great effort has been made towards the identification of the minimal gene complement necessary for life. In fact, the recent abundance of sequencing projects, particularly in the prokaryote kingdom, has driven this task. These computational analyses have proven very powerful, however, comparative genomics, aimed at identifying common gene sets among bacteria, can lead to underestimations because different organisms can use different genes to perform the same function. Furthermore, novel genetic approaches have provided us with lists of essential genes believed to represent the basic core of a living cell. Although the rest of the genes are apparently dispensable, they must exist for a reason. Intriguingly, many of the essential genes were revealed to have unknown functions despite being conserved in evolution, i.e. functions that remain obscure after this type of high-throughput analysis. This highlights how much of biology remains to be unveiled, even in the "simplest" unicellular organisms. The philosophy of this project is that, in order to understand the basics of a living device, we must go further and undertake a global analysis at all levels: from genomics to metabolomics, including gene expression profiling, proteome assessment survey of the protein-protein interactions, etc. Such approaches aimed, for the first time, at a whole quantitative understanding of an entire organism, are expected to guide rational engineering and putative genetic modifications. To reach this goal we have chosen Mycoplasma pneumoniae as our model organism. Mycoplasmas are the smallest self-replicating organisms (~500-1000 genes) rendering them suitable model organisms for systems biology and they are thought to fit the minimal genome paradigm. Their metabolism is scarce, reflecting the strong genomic simplification they have endured from their bacillus-like ancestor and due to the inability to synthesize precursors for cellular building blocks, such as nucleobases, amino acids, and fatty acids, they highly depend on their hosts for nutrition. Nevertheless, they can be maintained in vitro when their nutrition necessities are met.
The Mycoplasma consortium

This project could not be possible without the convergence of this lab and others at the European Molecular Biology Laboratory:
  • our team seeks to develop genetic and molecular biology tools, decipher the regulation of gene expression, the metabolic fluxes and accomplish the modelling of mycoplasma physiology
  • Peer Bork and colleagues have contributed to the bioinformatics analysis
  • Rob Russell lab has contributed to the bioinformatics analysis
  • Anne-Claude Gavin group is responsible for the interactome and is working on posttranslational modifications
  • Bettina Boettcher contributed to the the ultra-structure of selected macromolecules
  • Achilleas Frangakis contributed to the cryoelectron tomography
Other collaborators