The prevalence and mechanism of fluoroquinolone resistance in Escherichia coli isolated from swine farms in China

Table 2 The Sorting Intolerant From Tolerant (SIFT) scores of different mutations

	Topoisomerases and gyrase mutations									Efflux-related mutations
Genes	gyrA					parC		parE		marR		acrR
Sites	83	87	87	87	87	80	84	355	416^b	67^a	103	29^b
Amino acid alterations	S	D	D	D	D	S	E	I	L	D	G	V
Amino acid alterations	L	N	Y	G	H	I	K	T	F	N	S	G
Proven Scores	−4.2	−4.6	−8.3	−6.5	−6.3	−5.8	−3.9	2.9	−3.9	−4.4	1.4	−6.3
Prediction	DT	DT	DT	DT	DT	DT	DT	NT	DT	DT	NT	DT

Note: Score thresholds for prediction: Default threshold is −2.5, variant with a score equal to or below −2.5 are considered “deleterious”, variant with a score above −2.5 are considered “neutral”; QRDR fluoroquinolone resistance determining region, DT Deleterious, NT Neutral; ^a The novel mutation was found to be associated with fluoroquinolone resistance; ^bThe mutation has never been reported in China

ISSN: 1746-6148