Revision as of 14:26, 22 October 2010 by Jarax (Talk | contribs)

Example Tabs


Sed purus neque, suscipit vitae, cursus vitae, porttitor non, dui. Mauris volutpat dui vitae sapien. Duis laoreet nibh vitae sem.

Natural role: MinC is the component of MinCDE system. Together with nucleoid occlusion it ensures that cell division will occur in the middle of a cell. Three proteins – MinC, MinD and MinE play different role[s] in preventing formation of division complex too close to cell poles [1]. MinC is directly responsible for stopping the early stage of division by inhibiting the polymerysation [polymerization] of FtsZ protein monomers into [a] structure known as [the] Z-ring [8]. FtsZ is [a] tubuline homologue capable of creating chains, lariats and rings independent[ly] from [of] other cellular factors [3]. The stability and decay of these structures is dependent on GTPase activity of FtsZ proteins [7]. In [at] the beginning of cell division FtsZ monomers form the Z-ring to which other proteins responsible for the division are recruited. The presence of N-terminal domain of MinC prevents establishing additional Z-rings [9] [additional Z-rings from forming/being established]. In bacterial cells MinC is recruited to membrane by the second protein of the system – MinD. This process involves C-terminal domain of MinC, which is also responsible for oligomerisation of MinC [its oligomerisation]. Recrutation [recruitment] to membrane is necessary for the inhibiting effect to occur at the physiological concentration of protein [4]. Finally the third protein – MinE [-] is responsible for keeping the MinCD complex from acting in the midcell region[,] thus enabling the formation of Z-ring in the proper location [5]. It was shown that mutants in either minC or minD divide at cell pole much more often than wild type, resulting in creation of nucleoid-free minicells. This mutations, however are not lethal because enough of the cells in population divide properly to sustain growth [6]. Natural occurrence: Although MinCDE is mostly analysed in E.coli, it’s elements were found in many different bacteria groups including Proteobacteria, Deinococcus-Thermus and Firmicutes phyla [1]. In B. subtilis the MinE protein is replaced by DivIVa which locates itself at the cell poles and with help of MinJ binds MinCD complex, decreasing it’s concentration at midcell [2]. Application in synthetic biology: When expressed at high level MinC is capable of preventing bacteria[l] cell from dividing. As a result, of this [the] cell become[s] filamentus. These [this] effect requires only high level of MinC, not MinD. It was [has been] proven that overexpression of C-terminal domain of MinC alone is sufficient to inhibit cell division [9]. References: 1. “Themes and variations in prokaryotic cell division”, William Margolin, FEMS Microbiology Reviews 24 (2000) 531-548 2. “The MinCDJ System in Bacillus subtilis Prevents Minicell Formation by Promoting Divisome Disassembly”, Suey van Baarle and Marc Bramkami, PLoS One. 5 (2010) 3. “The bacterial cell division protein FtsZ assembles into cytoplasmic ring in fission yeast”, Ramanujam Srinivasan et al. Genes Dev. 22 (2008) 1741-1746 4. “The Switch I and II Regions of MinD Are Required for Binding and Activating MinC”, Huaijin Zhou and Joe Lutkenhaus, J Bacteriol. 186 (2004) 1546–1555. 5. “The MinE ring required for proper placement of the division site is a mobile structure that changes its cellular location during the Escherichia coli division cycle.”, Fu X et al. Proc. Natl. Acad. Sci. U S A 98. (2001) 6. “FtsZ ring cluster in min and partition mutants: Role of both the Min system and the nucleoid in regulation FtsZ ring location”, Yu et al. Mol. Microbiol. 32 (1999) 315-326 7. “FtsZ from Divergent Foreign Bacteria Can Function for Cell Division in Escherichia coli”, Masaki Osawa and Harold P. Erickson, J. Bacteriol. 188 (2006) 7132-7140 8. “FtsZ, a tubulin homologue in prokaryote division”, Trends. Cell Biol. 7 (1997) 362-367 9. “Analysis of MinC Reveals Two Independent Domains Involved in Interaction with MinD and FtsZ”, J. Bacteriol. 182 (2000) 3965-3971