Crosstalk between DnaA Protein, the Initiator of Escherichia coli Chromosomal Replication, and Acidic Phospholipids Present in Bacterial Membranes

International Journal of Molecular Sciences

Rahul Saxena²  Nicholas Fingland¹  Digvijay Patil²  Anjali K. Sharma² 

[1]Jet Propulsion Laboratory, California Institute of Technology, M/S: 183-426, 4800 Oak Grove Drive, Pasadena, CA 91109, USA

[2] E-Mail:

[3]Department of Biochemistry and Molecular & Cellular Biology Georgetown University Medical Center, Washington, DC 20007, USA

[4] E-Mails:

关键词: acidic phospholipids;    DnaA protein;    chromosomal replication;    Escherichia coli;   

DOI  :  10.3390/ijms14048517

来源: mdpi

【 摘 要 】

Anionic (i.e., acidic) phospholipids such as phosphotidylglycerol (PG) and cardiolipin (CL), participate in several cellular functions. Here we review intriguing in vitro and in vivo evidence that suggest emergent roles for acidic phospholipids in regulating DnaA protein-mediated initiation of Escherichia coli chromosomal replication. In vitro acidic phospholipids in a fluid bilayer promote the conversion of inactive ADP-DnaA to replicatively proficient ATP-DnaA, yet both PG and CL also can inhibit the DNA-binding activity of DnaA protein. We discuss how cellular acidic phospholipids may positively and negatively influence the initiation activity of DnaA protein to help assure chromosomal replication occurs once, but only once, per cell-cycle. Fluorescence microscopy has revealed that PG and CL exist in domains located at the cell poles and mid-cell, and several studies link membrane curvature with sub-cellular localization of various integral and peripheral membrane proteins. E. coli DnaA itself is found at the cell membrane and forms helical structures along the longitudinal axis of the cell. We propose that there is cross-talk between acidic phospholipids in the bacterial membrane and DnaA protein as a means to help control the spatial and temporal regulation of chromosomal replication in bacteria.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland