TABLE 2.

Spatial distribution of chemoreceptors^a

Strain	Plasmid-encoded CheA	Total no. of particles	No. of particles in cytoplasm	Membrane particlesb				No. of membrane particles/section	No. of polar clusters	Size of polar clustersd	No. of lateral clusters	Size of lateral clustersd
				Polar particlesc		Lateral particles
				%	% in clusters	%	% in clusters
AJW689	CheAL and CheAS	2,158	104	95	85	5	24	10.3	131	12.7 ± 0.9	5	4.8 ± 0.4
AJW688	CheAS	1,483	143	85	68	15	21	6.7	76	10.2 ± 0.6	7	5.7 ± 0.6
AJW1071	None	1,957	137	74	45	26	3	9.1	86	7.0 ± 0.3	3	4.3 ± 0.3

^aThe 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. 

^bThe 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. 

^cAll pairwise combinations are significantly different (P ≤ 0.05). 

^dNumbers of particles per cluster.