Sense and sensibility in bacteria. VIIIth International Conference on Bacterial Locomotion and Sensory Transduction

Abstract

VIIIth International Conference on Bacterial Locomotion and Sensory Transduction

Figure 1

Simplified diagrams of bacterial motility systems. (A) Schematic overview of simplified chemotactic signalling in flagellate Escherichia coli. Clusters of receptor–CheA kinase–CheW complexes signal chemotactic receptor occupancy by changing the phosphorylation state of cytoplasmic CheY signalling proteins, shifting the CheY conformational equilibrium towards the active conformation. The CheY-P proteins tactically modulate flagellar rotational behaviour by interaction with FliM switch proteins, located at the basal C ring of the flagellar motor. (Fig 2 shows a detailed atomic model of the receptor clusters shown in outline in this schematic). (B) Schematic overview of social 'S' gliding motility in Myxococcus xanthus. This type of motility depends on cell–cell contact and involves the interaction of type IV pili (Tfp) with extracellular polysaccharide layers (EPS) on adjacent cells (see part C). Movement is achieved by Tfp retraction after attachment. The FrzS protein moves dynamically between poles concomitant with reversals in Tfp-mediated S motility. (C) Schematic overview of Tfp–EPS contact in M. xanthus cells during social 'S' gliding motility.

Figure 2

Modelling of the density map derived from electron microscopic images of a soluble receptor/CheA/CheW complex (blue mesh) with atomic structures of the individual protein components (presented by P. Wolanin and described in more detail in Francis et al, 2004). The atomic structures are displayed in ribbon format and are CheA (cyan), CheW (magenta), and the cytoplasmic domain of the chemoreceptor (yellow and red).

The VIIIth International Conference on Bacterial Locomotion and Sensory Transduction (BLAST) was organized by R. Kadner, I. Kawagishi, P. O'Neill, J. Falke and J.S. Parkinson and was held in Boca Raton, FL, USA between 16 and 21 January 2005. This was the first BLAST Conference since the untimely death of Professor Robert Macnab of Yale University, one of the founders of the field of bacterial locomotion. We were delighted to inaugurate the first Bob Macnab prizes for poster presentations by young scientists. First prize went to Tatiana Besschetnova (Amherst, MA, USA; second on right), second prize to Collin Dyer (Santa Barbara, CA, USA; second on left), and third prize to Roger Alexander (Atlanta, GA, USA; far left). The winners received their awards from Bob's widow and co-researcher, May Kihara-Macnab (New Haven, CT, USA).