Table 3. Amino acid substitutions in PBP3 among 70 invasive H. influenzae strains.

BLNAR/BLPACR Genotype	Noisolates	Amino acid substitutions													MIC (mg/L)		BLa
		Ile 348	Asp350	Ala368	Met377	Met391	Ala437	Gly490	Ala502	Val509	Arg517	Asn526	Ala530	Phe531	AMP	AMC
No changesb	33														≤0.12	≤0.5	–
	3														>4	≤0.5	+
I	3										His				0.5	1	–
	1								Thr		His						–
IIa	1											Lys			1	2	–
	2		Asn					Glu				Lys	Ser		1	1–2	–
IIb	1								Val			Lys			0.5	1	–
	6		Asn		Ile				Val			Lys			0.5–4	1–4	–
	1		Asn		Ile				Val			Lys			>4	4	+
	2		Asn		Ile			Glu	Val			Lys			0.5–1	1–2	–
	1		Asn		Ile			Glu	Val			Lys			>4	4	+
IIc	2								Thr			Lys			1–2	2–4	–
	1								Thr			Lys			>4	4	+
	5		Asn						Thr			Lys			1–2	2–4	–
Miscellaneousc	1	Val													0.5	1	–
	1			Thr											≤0.12	≤0.5	–
	1		Asn												0.12	≤0.5	–
	2									Ile					0.25	≤0.5	–
	1													Leu	0.25	≤0.5	–
	2						Ser								0.25	≤0.5	–

^aBL: Beta-lactamase production: + (positive); – (negative).

^bIsolates without amino acid changes in PBP3 (gBLNAS).

^cIsolates grouped in the miscellaneous group were not gBLNAR.