Safety Evaluation of the Coagulase-Negative Staphylococci Microbiota of Salami: Superantigenic Toxin Production and Antimicrobial Resistance

Table 2

Genotypic and phenotypic characterization of CNS strains from salami.

Strains identification and characterization
Salami origin	Staphylococcus species	Genotypic		Phenotypic
	GenBank accession number and similarity (%)	Presence of enterotoxin genes	mRNA detection	Enterotoxin production (ng mL^−1)
Commercial	Staphylococcus spp. KF135445.1 (96)	sea, seb	—	—
	S. carnosus KJ862002.1 (96)	sea, seb, sed, seh, sei,and selj	—	1.2 ± 0.1
	S. carnosus NR116434.1 (98)	seb, sec, sed, and see	see	0.3
	S. saprophyticus AB697717.1 (98)	seh, sei, and selm	sei, selm	0.3
	S. saprophyticus EU430992.1 (99)	sea, seb, selm, seln, selo,and tstH1	seb, selm, and selo	1.3 ± 0.1
	S. saprophyticus HQ699510.1 (97)	—	—	—
	S. saprophyticus JX490122.1 (99)	sea, seh	seh	0.5 ± 0.1
	S. saprophyticus KJ004623.1 (96)	sec	—	0.4
	S. saprophyticus KJ949606.1 (98)	sea, seb, sec,and seh	sea, seb, and seh	—
	S. sciuri JX966436.1 (98)	sed, sei	sei	1.0 ± 0.1
	S. xylosus AM882700.1 (97)	—	—	—
	S. xylosus CP007208.1 (99)	—	—	—
	S. xylosus CP008724.1 (98)	sea, tstH1	sea	1.4
	S. xylosus KC456590.1 (98)	—	—	—
Artisanal	S. epidermidis KF600589.1 (97)	sec, sed, see, seg, seh,and sei	see, sei	0.7 ± 0.1
	S. hominis JX519988.1 (97)	sea, seb, sec, sed, selj, selm, seln, and selo	seln, selo	0.9 ± 0.1
	S. saprophyticus HF937252.1 (97)	seb	seb	0.5
	S. saprophyticus subsp. bovis KJ699151.1 (98)	sec, selm, seln,and tstH1	seln	0.9 ± 0.1
	S. succinus KC329824.1 (99)	sea, seb, sec, selj,and seln	seb, sec	1.3
	S. xylosus KF198080.1 (97)	sec, selm,and tstH1	—	0.5 ± 0.1

The presence of enterotoxin genes sea, seb, sec, sed, see, seg, seh, sei, selj, selk, selm, seln, selo, selq, selr, selu, and tstH1 was tested by PCR using the specific set of primers.
sea-see enterotoxin production was evaluated by immune-sorbent assays (ELISA) using the detection kit RIDASCREEN SET A, B, C, D, E. Values are displayed as the means ± SD of assays performed in duplicate.
mRNA transcripts for all enterotoxin genes were evaluated by real time RT-PCR tests.
CT values are displayed as means ± SD of RT-PCR tests performed in duplicate: sea—S. xylosus CP008724.1 30 ± 0.4; seb—S. xylosus CP008724.1 ; S. saprophyticus JX 490122.1 30.2 ± 0.4; S. saprophyticus subsp. bovis KJ699151.1 32 ± 0.1; S. xylosus KF198080.1 36 ± 1.0; and S. hominis JX519988.1 ; sec—S. saprophyticus subsp. bovis KJ699151.1 31 ± 1.1; see—S. saprophyticus subsp. bovis KJ699151.1 ; S. succinus KC329824.1 28.5 ± 0.1; and S. saprophyticus HF937252.1 32 ± 0.4; seh—S. xylosus CP008724.1 ; S. saprophyticus JX966436.1 33.2 ± 0.6; sei—S. saprophyticus AB697717.1 30 ± 1.0; S. saprophyticus JX966436.1 30.6 ± 1.0; seln—S. hominis JX519988.1 30.3 ± 1.0; S. saprophyticus EU430992.1 31 ± 0.3; and selo—S. hominis JX519988.1 .