TABLE 2.

Descriptive analysis of nucleotide sequence data

Gene	Length (% of full ORFa)	No. of:			G + C content (%)	π/siteb	kc	Tajima's D valued	No. of mutationse:		dN/dSf
		Polymor- phisms	Muta- tions	Alleles					Syn.	Nonsyn.
All isolates (n = 120)
actA	561 (29.2)	93	99	30	38.50	0.0543	30.44	2.10	41	51	0.32
gap	569 (56.3)	9	9	11	39.90	0.0037	2.11	0.62	6	3	0.04
inlA	771 (32.1)	72	73	33	41.10	0.0240	17.38	0.88	42	31	0.11
prs	633 (66.1)	46	46	12	40.80	0.0192	12.16	1.29	46	0
purM	714 (68.0)	146	162	29	42.00	0.0587	41.90	1.27	126	27	0.04
ribC	639 (67.6)	102	106	24	39.50	0.0562	35.90	2.64	97	9	0.02
sigB	666 (85.4)	38	38	14	38.60	0.0219	14.59	3.23	37	1	0.02
Lineage I isolates (n = 69)
actA	561	15	15	14	39.00	0.0061	3.39	0.25	6	9	0.97
gap	569	2	2	3	40.00	0.0010	0.56	0.56	2	0
inlA	771	17	17	12	41.10	0.0046	3.37	−0.14	6	11	0.32
prs	633	8	8	5	40.10	0.0021	1.30	−0.56	8	0
purM	714	8	9	12	42.40	0.0034	2.43	0.79	6	3	0.02
ribC	639	18	18	8	39.10	0.0062	3.99	0.19	15	3	0.06
sigB	666	9	9	8	38.60	0.0036	2.40	0.74	9	0
Lineage II isolates (n = 48)
actA	561	16	16	13	37.90	0.0064	3.56	−0.04	9	7	0.47
gap	569	9	9	8	39.80	0.0046	2.61	0.80	6	3	0.09
inlA	771	52	52	18	41.40	0.0218	16.60	1.45	34	18	0.12
prs	633	18	18	4	41.10	0.0027	1.73	−1.82	18	0
purM	714	122	132	15	41.60	0.0614	43.84	1.48	108	24	0.07
ribC	639	85	87	13	40.30	0.0359	22.94	0.61	80	7	0.01
sigB	666	27	27	4	38.50	0.0036	2.42	−2.00	26	1	0.01

^aORF, open reading frame.

^bAverage pairwise nucleotide difference per site.

^cAverage pairwise nucleotide differences per sequence.

^dTajima's D values significantly different from 0 (indicating deviation from standard neutral model) are marked in bold type.

^eSyn., synonymous; Nonsyn., nonsynonymous.

^fNo d_N/d_S ratio was determined when no nonsynonymous mutations were observed.