Point Mutations in the folP Gene Partly Explain Sulfonamide Resistance of Streptococcus mutans

Table 1

Characteristics of bacterial isolates used in the current study, the respective genes and susceptibility to Cotrimoxazole (STX), sulfamethoxazole (SMX), and trimethoprim (TMP) as determined by 𝐸-test.

Isolate	Accession number of folP gene nucleotide sequence used	Mutations in the folP gene	STX	Sulfonamide susceptibility	Trimethoprim susceptibility	Mutations in the folA gene
S. mutans 8	Not yet submitted to gene banks but previously published [7]	A37V, N172D, and R193Q*	>32 𝜇g/mL	>1024 𝜇g/mL; (>4 mM)	>32 𝜇g/mL	None
S. mutans 797	HE599533.1	A46V, E80K, Q122H, and S146G**	0.5 𝜇g/mL	>1024 𝜇g/mL; (>4 mM)	2 𝜇g/mL	None
S. mutans 135	Not yet submitted but previously published [7]	A63S, W174LK, L175F, and M189I**	8 𝜇g/mL	>1024 𝜇g/mL; (>4 mM)	0.38 𝜇g/mL	None
S. sobrinus 7	HE 599535.1	None	>32 𝜇g/mL	>1024 𝜇g/mL; (>4 mM)	>32 𝜇g/mL	None
S. downei 477	Similar to ZP 07725257.1	None	0.125 𝜇g/mL	Not done	Not done	Not done

∗Mutations as compared to UA159 [10]. **Mutations as compared to NN2025 [11].