Table 2.

Spatial distribution of chemoreceptorsa

StrainPlasmid-encoded CheATotal no. of particlesNo. of particles in cytoplasmMembrane particlesbNo. of membrane particles/sectionNo. of polar clustersSize of polar clustersdNo. of lateral clustersSize of lateral clustersd
Polar particlescLateral particles
%% in clusters%% in clusters
AJW689CheAL and CheAS 2,158104958552410.313112.7 ± 0.954.8 ± 0.4
AJW688CheAS 1,483143856815216.77610.2 ± 0.675.7 ± 0.6
AJW1071None1,95713774452639.1867.0 ± 0.334.3 ± 0.3
  • a The numbers and positions of gold particles detected by immunomicroscopy from 200 thin sections of cells are shown. The numbers and sizes of gold particle clusters located in either the polar or lateral membrane were determined. The relative size of the clusters ± 1 standard error of the mean is presented. CheA expression was uninduced in strains AJW689 and AJW1071 and induced with 50 μM IPTG in strain AJW688.

  • b The percentages of gold particles at the poles or along the lateral edges and the percentage of polar or lateral gold particles that are clustered are shown.

  • c All pairwise combinations are significantly different (P ≤ 0.05).

  • d Numbers of particles per cluster.