TABLE 2.

Quantitative analysis of H. pylori pili^a

Strain name or description	Mean (± SE) no. of pili per bacterial cellb	% (± SE) of bacteria with visible pilic
26695	4.1 ± 0.6	81.9 ± 5.9
Δcag PAI	Not detected*	Not detected*
ΔrdxA	3.1 ± 0.4	82.3 ± 3.2
ΔrpsL	3.8 ± 0.8	72.5 ± 8.6
cag3 marked mutant	0.02 ± 0.02*	0.0 ± 0.0*
cag3 unmarked mutant	Not detected*	Not detected*
cag3 complemented mutant	5.0 ± 1.1	75.0 ± 5.8
cagC marked mutant	3.8 ± 1.2	79.0 ± 6.1
cagC unmarked mutant	2.4 ± 0.7	70.8 ± 7.5
cagM marked mutant	0.1 ± 0.1*	0.0 ± 0.0*
cagM unmarked mutant	Not detected*	Not detected*
cagM complemented mutant	3.7 ± 0.9	85.8 ± 4.6
cagT marked mutant	Not detected*	Not detected*
cagT complemented mutant	5.7 ± 0.8*	74.4 ± 5.4
cagV marked mutant	Not detected*	Not detected*
cagV unmarked mutant	Not detected*	Not detected*
cagV complemented mutant	4.8 ± 1.2	79.2 ± 8.6
cagX marked mutant	Not detected*	Not detected*
cagX unmarked mutant	Not detected*	Not detected*
cagX complemented mutant	4.4 ± 1.1	77.3 ± 8.4
cagY marked mutant	5.4 ± 1.1	81.7 ± 6.2

^aSE, standard error of the mean. *, P < 0.005 compared to results for the parental strain, based on two-tailed t test analysis.

^bImages of at least 20 adherent bacterial cells, derived from three separate experiments, were analyzed. Among the strains capable of pilus production, nonpiliated bacteria were included in the analysis.

^cPercent piliated bacteria were quantified based on images of at least 10 fields, derived from three separate experiments.