Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

Bacterial chemosensory proteins form large hexagonal arrays. Several key features of chemotactic signaling depend on these large arrays, namely, cooperativity between receptors, sensitivity, integration of different signals, and adaptation. The best-studied arrays are the membrane-associated arrays found in most bacteria.Rhodobacter sphaeroideshas two spatially distinct chemosensory arrays, one is transmembrane and the other is cytoplasmic. These two arrays work together to control a single flagellum. Deletion of one of the soluble chemoreceptors, TlpT, results in the loss of the formation of the cytoplasmic array. Here, we show the expression of TlpT in atlpTdeletion background results in the reformation of the cytoplasmic array. The number of arrays formed is dependent on the cell length, indicating spatial limitations on the number of arrays in a cell and stochastic assembly. Deletion of PpfA, a protein required for the positioning and segregation of the cytoplasmic array, results in slower array formation upon TlpT expression and fewer arrays, suggesting it accelerates cluster assembly.IMPORTANCEBacterial chemosensory arrays are usually membrane associated and consist of thousands of copies of receptors, adaptor proteins, kinases, and adaptation enzymes packed into large hexagonal structures.Rhodobacter sphaeroidesalso has cytoplasmic arrays, which divide and segregate using a chromosome-associated ATPase, PpfA. The expression of the soluble chemoreceptor TlpT is shown to drive the formation of the arrays, accelerated by PpfA. The positioning of thesede novoarrays suggests their position is the result of stochastic assembly rather than active positioning.

Original publication




Journal article


J Bacteriol

Publication Date





Rhodobacter sphaeroides, chemoreceptor, chemotaxis, protein positioning, Bacterial Proteins, Chemotaxis, Cytoplasm, Membrane Proteins, Rhodobacter sphaeroides, Signal Transduction