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Table 4 Downregulation of the rnaIII gene activity of Staphylococcus aureus by three different culture preparations obtained from bovine non-aureus staphylococci (NAS) isolates from milk and teat apices (TA) [no. (%)]

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

NAS species (no.)1 SP2 [no. (%)] SPK [no. (%)] CS [no. (%)] All culture preparations [no. (%)]
Milk (45) TA (14) Total (59) Milk (45) TA (14) Total (59) Milk (45) TA (14) Total (59) Milk (45) TA (14) Total (59)
All (59)
 Severe effect3 12 (26.7) 6 (42.8) 18 (30.5) 5 (11.1) 2 (14.3) 7 (11.9) 1 (2.2) 1 (7.1) 2 (3.4) 18 (13.4) 9 (21.4) 27 (15.2)
 Moderate effect 24 (53.3) 2 (14.3) 26 (44.1) 26 (57.8) 7 (50.0) 33 (56.0) 2 (4.5) 4 (28.6) 6 (10.2) 52 (38.5) 13 (30.9) 65 (36.8)
 Slight effect 1 (2.2) 2 (14.3) 3 (5.1) 3 (6.7) 1 (7.1) 4 (6.7) 17 (37.8) 4 (28.6) 21 (35.6) 21 (15.5) 7 (16.8) 28 (15.8)
 No effect 8 (17.8) 4 (28.6) 12 (20.3) 11 (24.4) 4 (28.6) 15 (25.4) 25 (42.4) 5 (35.8) 30 (50.8) 44 (32.6) 13 (30.9) 57 (32.2)
S. chromogenes (34)
 Severe effect 2 (7.1) 2 (33.4) 4 (11.7) 2 (7.1) 0 2 (5.9) 1 (3.6) 1 (16.6) 2 (5.9) 5 (6.0) 3 (16.7) 8 (7.8)
 Moderate effect 24 (85.7) 2 (33.4) 26 (76.5) 19 (67.9) 5 (83.4) 24 (70.6) 1 (3.6) 3 (50.0) 4 (11.7) 44 (52.4) 10 (55.5) 54 (53.0)
 Slight effect 1 (3.6) 1 (16.6) 2 (5.9) 3 (10.7) 0 3 (8.8) 13 (46.4) 1 (16.7) 14 (41.2) 17 (20.2) 2 (11.1) 19 (18.6)
 No effect 1 (3.6) 1 (16.6) 2 (5.9) 4 (14.3) 1 (16.6) 5 (14.7) 13 (46.4) 1 (16.7) 14 (41.2) 18 (21.4) 3 (16.7) 21 (20.6)
S. epidermidis (11)
 Severe effect 0 1 (25.0) 1 (9.1) 0 0 0 0 0 0 0 1 (8.3) 1 (3.0)
 Moderate effect 0 0 0 0 1 (25.0) 1 (9.1) 1 (14.3) 1 (25.0) 2 (18.2) 1 (4.7) 2 (16.7) 3 (9.0)
 Slight effect 0 0 0 0 0 0 0 0 0 0 0 0
 No effect 7 (100) 3 (75.0) 10 (90.9) 7 (100) 3 (75.0) 10 (90.9) 6 (85.7) 3 (75.0) 9 (81.8) 20 (95.3) 9 (75.0) 29 (88.0)
S. simulans (14)
 Severe effect 10 (100) 3 (75.0) 13 (92.8) 3 (30.0) 2 (50.0) 5 (35.7) 0 0 0 13 (43.4) 5 (41.6) 18 (42.9)
 Moderate effect 0 0 0 7 (70.0) 2 (50.0) 9 (64.3) 0 0 0 7 (23.3) 2 (16.7) 9 (21.4)
 Slight effect 0 1 (25.0) 1 (7.2) 0 0 0 4 (40.0) 3 (75.0) 7 (50.0) 4 (13.3) 4 (33.4) 8 (19.0)
 No effect 0 0 0 0 0 0 6 (60.0) 1 (25.0) 7 (50.0) 6 (20.0) 1 (8.3) 7 (16.7)
  1. 1 Culture preparations = SP–Supernatant; SPK–Supernatant + Proteinase K; CS–Cell suspension.
  2. 2 Number of isolates.
  3. 3 Regulation effect was rated according to the size of inhibition zone around the well (measured in mm) [12] and was classified as exhibiting no effect (≤ 10 mm), a slight effect (11–15 mm), a moderate effect (16–20 mm), and a severe effect (≥ 25 mm) on gene expression.