The positioning of cytoplasmic protein clusters in bacteria.
Cell division is a carefully orchestrated procedure. Bacterial cells have intricate mechanisms to ensure that genetic material is copied, proofread, and accurately partitioned into daughter cells. Partitioning now appears to also occur for some cytoplasmic proteins. Previously, using chromosomal fluorescent protein fusions, we demonstrated that a subset of Rhodobacter sphaeroides chemotaxis proteins colocalize to a discrete region within the bacterial cytoplasm. Using TlpT-yellow fluorescent protein as a marker for the position of the cytoplasmic protein clusters, we show most cells contain either one cluster localized at mid-cell or two clusters at the one-fourth and three-fourths positions of cell length. The number and positioning of these protein clusters depend on a previously unrecognized bacterial protein positioning factor, PpfA, which has homology to bacterial type I DNA partitioning factors. These data suggest that there is a mechanism involved in partitioning some cytoplasmic proteins upon cell division that is analogous to a mechanism seen for plasmid and chromosomal DNA.
Thompson
Stephen R
SR
Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
Wadhams
George H
GH
Armitage
Judith P
JP
D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000737:chemistry*; D002455:Cell Division; D002633:Chemotaxis; D003593:Cytoplasm / Q000378:metabolism*; D004247:DNA / Q000737:chemistry; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000737:chemistry; D008856:Microscopy, Fluorescence; D011485:Protein Binding; D012242:Rhodobacter sphaeroides / Q000378:metabolism*; D013997:Time Factors
D001426:Bacterial Proteins; D008565:Membrane Proteins; D004247:DNA