Molecular Biology of the Bacterium Mycoplasma pneumoniae

• Global transcription analysis
• Expression signals and regulation of transcription
• Proteome (total proteins expressed by a genome) analysis 
• Structural proteins involved in formation of a "bacterial cytoskeleton" 
• Comparative studies of closely related species (M. genitalium) and isolates of the same species

Global transcription analysis

C.-U. Zimmermann, J. Weiner

To establish a transcription profile of a complete cell, 687 DNA fragments were synthesized by polymerase chain reaction which are specific for the 687 proposed open reading frames coded for the M. pneumoniae genome. Transcription is measured by hybridizaiton with labelled cDNA reverse transcribed from total RNA of M. pneumoniae.
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Expression signals and regulation of transcription

J. Weiner in cooperation with G. Browning, University of Melbourne and A. Wieslander, University of Stockholm and M. Sjöström, University of Umea

Based on the results from the global transcription analysis, gene expression signals from differently expressed genes were experimentally defined and the regulation of expression of these selected genes are being studied. In addition, numerical analyses of regulatory signals in the region upstream of the proposed start of transcription are being done applying multivariate statistical methods.
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Proteome (total proteins expressed by a genome)

B. Überle in cooperation with T. Ruppert,  ZMBH, Heidelberg

The proteome of M. pneumoniae can be visualized as a highly reproducible pattern of separated protein spots in a two-dimensional acrylamide gel (protein map). Individual proteins are being identified by determining the molecular weight and the amino acid sequence of their tryptic peptids by mass spectrometry. If these data agree with the peptide predictions based on the genomic DNA sequence, than, a protein is appointed to its gene.
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Structural proteins involved in formation of a "bacterial cytoskeleton"

J. Hegermann, A. Boonmee, W. Schaller, E. Pirkl in cooperation with F. Mayer, University Göttingen

M. pneumoniae has a specific cytoskeleton-like structure, not found so far in other bacterial genus except Mycoplasma. This structure is compensating probably for the lack of a cell wall and protects M. pneumoniae against osmotic and mechanic stress. Composition of this structure, characterization of individual components and their interaction are under investigation.
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Comparative studies of M. pneumoniae isolates from patients and closely related species (Mycoplasma genitalium) 

I. Catrein, E. Pirkl

Comparative studies between Mycoplasma genitalium (Fraser et al., 1995) and independent isolates of M. pneumoniae from patients are being exploited to identify and analyse genes involved in interaction between M. pneumoniae and its host (cell).
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