Table 3.

Presence of the 16S Tigurinus motif, the 16S CTT-motif, and six virulence-associated genes among endocarditis strains in the collection (SN) and S. tigurinus reference strains.

Strain	Tigurinus-motif	CTT-motif	rib-like	int	cshA-like	pitA-like, hylA-likea	gtfR
S. oralis ATCC 35037- resp. ATCC 49296-like strains according to 16S and housekeeping genes
SN 17127	Negative	Negative	Negative	Negative	Positive	Negative	Positive
SN 31376	Negative	Negative	Negative	Negative	Positive	Negative	Positive
SN 51446	Negative	Negative	Negative	Negative	Positive	Negative	Positive
SN 60579	Negative	Negative	Negative	Negative	Positive	Negative	Positive
SN 58746	Negative	Negative	Negative	Negative	Negative	Negative	Positive
SN 59433	Negative	Negative	Negative	Negative	Negative	Negative	Positive
S. oralis–S. tigurinus linker strains
SN 16495	Negative	positive	Negative	Negative	Positive	Negative	Positive
SN 50746	Positive	Negative	Negative	Negative	Negative	positive	Negative
SN 63707	Negative	Positive	Negative	Negative	Positive	Negative	Negative
S. tigurinus–like strains according to 16S and housekeeping genes
SN 37569	Positive	Positive	Negative	Negative	Negative	Negative	Positive
SN 28194	Positive	Negative	Negative	Negative	Negative	Negative	Negative
SN 37737	Positive	Negative	Negative	Negative	Negative	Negative	Negative
SN 40525	Positive	Negative	Negative	Negative	Negative	Negative	Negative
SN 45448	Positive	Negative	Negative	Negative	Negative	Negative	Negative
SN 62386	Positive	Negative	Positive	Positive	Negative	Negative	Negative
S. tigurinus reference strains
AZ_3aT	Positive	Negative	Positive	Positive	Positive	Positive	Negative
1366	Positive	Positive	Negative	Negative	Positive	Negative	Negative
2425	Positive	Positive	Negative	Negative	Positive	Negative	Negative
2426	Positive	Positive	Negative	Negative	Positive	Negative	Negative
ATCC 6249-like strains according to 16S and housekeeping genes
SN 39325	Negative	Negative	Negative	Negative	Negative	Negative	Negative
SN 48861	Positive	Negative	Negative	Negative	Negative	Negative	Negative
SN 54787	Negative	Negative	Negative	Negative	Negative	Negative	Negative
SN 54788	Negative	Negative	Negative	Negative	Negative	Negative	Negative
SN 58364	Negative	Negative	Negative	Negative	Negative	Negative	Negative
S. infantis–like strains according to 16S and housekeeping genes
SN 17128	Negative	Negative	Negative	Negative	Negative	Negative	Negative
SN 19640	Negative	Negative	Negative	Negative	Negative	Negative	Negative
SN 57625b	Negative	Negative	Negative	Negative	Negative	Negative	Negative

All typical S. oralis strains hold gtfR, and all S. tigurinus–like strains do not hold gftR. Three strains (SN 16495, SN 50746, and SN 63707) are placed between S. oralis and S. tigurinus according to housekeeping gene information and might be hybrids. Five strains are related to ATCC 6249 according to housekeeping genes, which could be evidence for another subclade or ‘(sub-)species’.

^aThese genes always appeared together.

^bIn strain SN 57625, the gdh could not be amplified.