Localization of acidic phospholipid cardiolipin and DnaA in mycobacteria

Abstract

Acidic phospholipids such as cardiolipin (CL) have been shown to modulate Mycobacterium tuberculosis (Mtb) DnaA interactions with ATP. In the present study, using nonyl acridine orange fluorescent dye we localized CL-enriched regions to midcell septa and poles of actively dividing cells. We also found that CL-enriched regions were not visualized in cells defective for septa formation as a consequence of altered FtsZ levels. Using Mtb cultures synchronized for DNA replication we show that CL localization could be used as a marker for cell division and cell cycle progression. Finally, we show that the localization pattern of the DnaA-green fluorescent fusion protein is similar to CL. Our results suggest that DnaA colocalizes with CL during cell cycle progression.

Content of cardiolipin of the membrane and sensitivity to cationic surfactants inPseudomonas putida

“…This is explained by the multiple functions exerted by CL in for example, cell division and DNA replication (Mileykovskaya and Dowhan ; Maloney et al . ; Renner and Weibel ), functionality and stability of certain membrane proteins (Romantsov et al . ; Schlame ), performance of efflux pump (Bernal et al .…”

“…Different studies show that bacteria with deficiency in the content of CL are more susceptible to different stress situations. This is explained by the multiple functions exerted by CL in for example, cell division and DNA replication (Mileykovskaya and Dowhan 2009;Maloney et al 2011;Renner and Weibel 2011), functionality and stability of certain membrane proteins (Romantsov et al 2007;Schlame 2008), performance of efflux pump (Bernal et al 2007b) and membrane bioenergetic processes (Arias-Cartin et al 2012 and citations therein). In the present study, we analysed the role of the CL levels in response to the presence of TTAB in Ps.…”

Cardiolipin and mitochondrial cristae organization

“…rods, cocci, spiral) and overall lipid composition, more work is required to understand the precise role(s) of cardiolipin in different bacterial species. A common feature relating E. coli to bacteria in general, however, is the proposed role of cardiolipin in binary fission as a component of membrane septa formation during cell division [36-38]. …”

Metabolism of Plasma Membrane Lipids in Mycobacteria and Corynebacteria

“…Nonyl acridine orange (NAO) is a fluorescent dye which is proposed to bind the hydrophobic surface created by the CL cluster [14], allowing microscopic visualization of CL domains. Indeed, using NAO, CLs were found to be enriched in septa and poles of actively dividing M. tuberculosis and M. smegmatis cells [15,16]. CL has a non-bilayer structure [17,18], and carries a small partially immobilized head group that is more exposed to the aqueous environment than those of other glycerophospholipids [19].…”