Metabolites of bovine-associated non-aureus staphylococci influence expression of Staphylococcus aureus agr-related genes in vitro

Table 2 Final linear mixed effect model for the β-galactosidase liquid assay for rnaIII gene expression including the positive and negative controls

Predictor variables	β¹	SE²	LSM³	P value⁴
Intercept	2.24	0.20	–
Time of measurement				0.0453
1 h	Referent	–	40.95
2 h	−0.08	0.13	46.83
3 h	0.09	0.16	53.35
4 h	0.20	0.19	58.95
Staphylococcal species⁵				< 0.0001
S. aureus (negative control)	Referent	–	196.52
S. aureus + S. schleiferi (positive control)	−0.78	0.28	23.72
S. aureus + S. chromogenes	−0.76	0.20	36.20
S. aureus + S. epidermidis	−0.78	0.21	60.63
S. aureus + S. simulans	−0.82	0.21	29.22
Staphylococcal species x Time of measurement⁶				< 0.0001

¹ Estimate.
² Standard error.
³ Least square means after back transformation.
⁴ Overall P value for fixed effects.
⁵ Staphylococcus aureus rnaIII::lacZ reporter strain SH101F7 was used as negative control when growing alone and as positive control when in co-culture with Staphylococcus schleiferi strain 2898.
⁶ The interaction term is visualized in Figure 2A.

ISSN: 1297-9716