Table 1. futA and futB genotypes in an H. pylori population colonizing human gastric mucosa.

	futA			futB
Subisolate	Type1	C-tract2	Heptads3	Type	C-tract	Heptads
67:15	A	13 −	2	B	13 +	8
67:16	A	12 −	2	B	13 +	8
67:17	A*	13 −	2	B	13 +	8
67:18	A*	14 +	5	B	13 +	7
67:19	A*	13 −	2	B	13 +	8
67:20	B	12 −	17	B-A	13 +	5
67:21	A	12 −	2	B	13 +	8
67:22	A	12 −	2	B	13 +	8
67:23	A	13 −	2	B	13 +	8
67:24	A	13 −	2	B	13 +	8
67:25	A	12 −	2	B	13 +	8
67:26	A	12 −	2	B	13 +	8
67:27	B	12 −	15	B-A	13 +	5
67:28	A	12 −	2	B	13 +	8
67:29	A	13 −	2	B	13 +	8
67:30	A	13 −	2	B	13 +	8
67:31	A	12 −	2	B	13 +	8
67:32	A	13 −	2	B	13 +	8
67:33	A	13 −	2	B	13 +	8
67:34	A	12 −	2	B	13 +	7

¹ fut allele at locus, based on sequencing of 200 bp at the 5′ of gene. The types A and B are referred to the genetic sequence present at the corresponding locus in strain 67:21. A^* differs from A at two nucleotide positions, according to Figure 7.

²Number of C-residues in 5′ homopolymeric tract and reading frame of the gene (+ in frame, − out of frame)

³Number of C-terminal heptad-repeats