Mycoplasma genitalium

Balasubramanian S et al. Proteomics of Mycoplasma genitalium identification and characterization of unannotated and atypical proteins in a small model genome. Nucleic Acids Res 2000 28 3075-3082. 

Some bacteria possess uptake systems of all the ABC types mentioned in this chapter. For example, the pathogenic microbe H. influenzae is able to sequester iron via siderophore-type systems, ferric iron systems, and metal-type systems. Similarly, strains of Yersinia use multiple routes to take up iron bound to siderophores (e.g. yersiniabactin) and haem, as well as unliganded iron by the ferric-iron-type Yfu system and the metal-type Yfe system. No iron-uptake systems of the ABC transporter type were identified in the genomes of Mycoplasma genitalium and Mycoplasma pneumoniae. In contrast, among the 19 ABC transporters of the related species Ureaplasma urealyticum six presumed different Fe3+ and/or haem transporters were identified [228]. 

Fig. 6. Distribution of the most common folds in selected bacterial, archaeal, and eukaryotic proteomes. The vertical axis shows the fraction of all predicted folds in the respective proteome. Fold name abbreviations FAD/NAD, FAD/NAD(P)-binding Rossman-like domains TIM, TIM-barrel domains SAM-MTR, S-adenosylmethionine-dependent methyltransferases PK, serine-threonine protein kinases PP-Loop, ATP pyrophosphatases. mge, Mycoplasma genitalium rpr, Rickettsiaprowazekii hh x, Borrelia burgdorferi ctr, Chlamydia trachomatis hpy, Helicobacter pylori tma, Thermotoga maritima ssp, Synechocystis sp. mtu, Mycobacterium tuberculosis eco, Escherichia coli mja, Methanococcus jannaschii pho, Pyrococcus horikoshii see, Saccharomyces cerevisiae, cel, Caenorhabditis elegans.

Huynen, M., Doerks, T., Eisenhaber, F., Orengo, C., Sunyaev, S., Yuan, Y., and Bork, P. (1998). Homology-based fold predictions for Mycoplasma genitalium proteins. / Mol. Biol. 280, 323-326. 

Rychlewski, L., Zhang, B., and Godzik, A. (1998). Fold and function predictions for Mycoplasma genitalium proteins. Fold. Des. 3, 229—238. 

Teichmann, S. A., Park, J., and Chothia, C. (1998). Structural assignments to the Mycoplasma genitalium proteins show extensive gene duplications and domain rearrangements. Proc. Natl. Acad. Sd. U.S.A. 95, 14658—14663. 

Mycoplasma genitalium and Buchneva are considered the simplest cells, with a genome containing less than 500 coding regions. These are, however, parasites and the next step of complexity concerns microbes with thousands of expressed proteins, which catalyze thousands of reactions more or less simultaneously within the same tiny compartment - a maze of enormous complexity. However, precisely this complexity elicits the question of whether such complexity is really essential for life - or whether instead cellular life might be possible with a much smaller number of components. 

Mycoplasma genitalium 580 Obligate parasite Fraser etal., 1995... 

Classification of endosymbionts as a group by themselves shows that their DNA content can be significantly smaller, reaching a value of 450 kb for Buchnera spp. (Gil et al., 2002) or a value of 580 kb for the obligate parasite Mycoplasma genitalium (Fraser etal, 1995). 

Wasinger VC, Cordwell SJ, Cerpa-Poljak A et al. Progress with gene-product mapping of the Molli-cutes Mycoplasma genitalium. Electrophoresis 1995 16 1090-1094. 

CM Fraser, JD Gocayne, O White, MD Adams, RA Clayton, RD Fleishmann, CJ Bult, AR Kerlavage, G Sutton, JM Kelley, JL Fritchman, JF Weidman, KV Small, M Sandusky, J Fuhrmann, D Nguyen, TR Utterback, DM Saudek, CA Phillips, JM Merrick, J-F Tomb, BA Dougherty, KF Bott, P-C Hu, TS Lucier, SN Peterson, HO Smith, CA Hutchison, JC Venter. The minimal gene complement of Mycoplasma genitalium. Science 270 397-403, 1995. 

Merrick, et al. The minimal gene complement of Mycoplasma genitalium. Science 270 397-403, 1995. 

Gibson DG et al (2008) Complete chemical synthesis, assembly, and cloning of a Mycoplasma genitalium genome. Science 319 1215-1220... 

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