Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from symptomatic men attending the Nanjing sexually transmitted diseases clinic (2011–2012): genetic characteristics of isolates with reduced sensitivity to ceftriaxone

Table 3 Genetic characteristics of Neisseria gonorrhoeae with increased MICs (n = 15) to ceftriaxone (≥0.125 mg/L)

Isolate no.	Ceftriaxone MICs (mg/L)	Antimicrobial characteristics	NG-MAST			PBP2 allele	Polymorphisms in:
Isolate no.	Ceftriaxone MICs (mg/L)	Antimicrobial characteristics	porB	tbpB	STs	PBP2 allele	MtrR	PorB1b	PBP1	PilQ
NJ-1	0.25	CMRNG, CipR^#	5658	111	9530*	XVIII	−57A del, A39T	G120K, A121D	L421P	wt
NJ-2	0.25	CMRNG, CipR	5175	328	8737	XVIII	−57A del, A39T	G120K, A121D	L421P	wt
NJ-3	0.125	PPNG, CipR	5659	107	9531*	XVIII	−57A del	G120K, A121G	L421P	wt
NJ-4	0.125	PP/TRNG, CipR	1053	186	3289	XVIII	−57A del	G120K, A121D	L421P	wt
NJ-5	0.125	PPNG, CipR	1854	33	9532*	XLI**	−57A del	G120N, A121D	L421P	wt
NJ-6	0.125	PP/TRNG, CipR	543	294	9533*	XVIII	A39T	G120K, A121G	L421P	wt
NJ-7	0.125	CMRNG, CipR	5660	186	9534*	XVIII	−57A del	G120K, A121G	L421P	wt
NJ-8	0.125	CMRNG, CipR	505	135	2186	XVIII	−57A del	G120K, A121D	L421P	wt
NJ-9	0.125	CMRNG, CipR	1285	4	9535*	XIII	−57A del, G45D	G120K, A121D	L421P	wt
NJ-10	0.125	TRNG, CipR	4	831	3746	XIII	−57A del	G120K, A121D	L421P	wt
NJ-11	0.125	CMRNG, CipR	3530	4	9536*	XVIII	−57A del	G120K, A121G	L421P	wt
NJ-12	0.125	CMRNG, CipR	1198	156	2461	XVIII	−57A del, A39T	G120K, A121G	L421P	wt
NJ-13	0.125	CMRNG, CipR	5661	4	5061	XVIII	−57A del, G45D	G120K, A121N	L421P	wt
NJ-14	0.125	CMRNG, CipR	2978	1058	9537*	XII	−57A del	G120K, A121D	L421P	wt
NJ-15	0.125	TRNG, CipR	543	438	9538*	XVIII	−57A del	G120K, A121G	L421P	wt

wt, wild type.
*New NG-MAST STs detected in this study.
**A new PBP2 allele previously not identified was named XLI according to previously used Nomenclature.
^#isolates exhibiting resistance to ciprofloxacin (MIC ≥ 1 mg/L).