TABLE 5.
Biochemical profiles of presumptive E. fergusonii isolates determined by API 20E
| Type of isolate | No. of isolates | API 20E ID % | Biochemical profilec |
Total no. of E. fergusonii isolates by PCRa,b | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ONPG | ADH | LDC | ODC | VP | SOR | RHA | SAC | MEL | AMY | ||||
| Control | 1 | E. fergusonii (ATCC) | + | − | + | + | − | − | + | − | − | + | 1 |
| Control | 1 | E. coli 1 (ATCC) | + | − | + | + | − | + | + | − | + | − | 0 |
| Control | 1 | Kluyvera spp. (ATCC)d | + | − | − | + | − | − | + | + | + | + | 0 |
| A | 7 | E. fergusonii 99.8% | + | − | + | + | − | − | − | − | − | + | 7 |
| B | 23 | E. fergusonii 99.6% | − | − | + | + | − | − | + | − | − | + | 23 |
| C | 102 | E. fergusonii 98.9% | + | − | + | + | − | − | + | − | − | + | 102 |
| D | 3 | E. fergusonii 97.4% | − | − | + | + | − | − | − | − | − | + | 3 |
| E | 2 | E. fergusonii 89.2%, Kluyvera spp. 5.8% | + | + | + | + | − | − | + | − | + | + | 2 |
| F | 3 | E. fergusonii 70.8%, E. coli 1 22.5% | + | − | + | + | − | − | + | − | − | − | 3 |
| G | 7 | E. fergusonii 68.2%, Kluyvera spp. 26.4% | + | − | + | + | − | − | − | − | + | + | 7 |
| H | 18 | E. fergusonii 56.2%, Kluyvera spp. 40.6% | + | − | + | + | − | − | + | − | + | + | 18 |
| I | 5 | E. fergusonii 55.9%, Kluyvera spp. 40.4% | + | − | + | + | + | − | + | − | + | + | 5 |
| J | 8 | Kluyvera spp. 42.7%, E. fergusonii 29% | − | − | + | + | − | − | + | + | − | + | 8 |
| K | 61 | E. hermannii 59.5%, E. fergusonii 17.3% | + | − | + | + | − | − | + | + | − | + | 61 |
| L | 2 | E. coli 1 99.9% | + | − | + | − | − | + | + | + | + | − | 0 |
| M | 1 | E. coli 1 99.8% | + | + | + | + | − | + | + | + | + | − | 0 |
| N | 5 | E. coli 1 99.8% | + | − | + | − | − | + | + | − | + | − | 0 |
| O | 3 | E. coli 1 98.9% | + | + | + | + | − | − | + | + | + | − | 0 |
| P | 2 | E. coli 1 98.4% | + | − | + | + | − | + | + | + | + | − | 0 |
| Q | 1 | E. coli 1 98.1% | + | + | + | + | − | − | + | − | + | − | 1 |
| R | 9 | E. coli 1 97.7% | + | − | + | + | − | − | + | − | + | − | 3 |
| S | 3 | E. coli 1 97.2% | + | − | + | − | − | − | + | − | + | − | 0 |
| T | 6 | E. coli 1 96.3% | + | − | + | + | − | − | − | − | + | − | 6 |
| U | 1 | E. coli 1 93.3% | − | − | + | + | − | − | + | − | + | − | 1 |
| V | 11 | Leclercia adecarboxylata 64.2%, E. coli 22.7% | + | − | − | − | − | − | + | − | + | − | 0 |
| W | 18 | Kluyvera spp. 99.3% | + | − | + | + | − | − | + | + | + | + | 18 |
| Total | 304e | 269f | |||||||||||
A total of 301 presumptive isolates were tested by both API 20E and PCR; 140 were identified as E. fergusonii by API 20E at an identification accuracy of ≥70%, and 268 were identified as E. fergusonii by PCR.
There was a significant difference in the detection of E. fergusonii by API 20E versus detection by PCR (P < 0.0001), with a risk factor of 56.57 when using PCR as the detection method.
All samples were negative for sodium thiosulfate (H2S), urea (URE), l-tryptophane (TDA), gelatin (GEL), and inositol (INO); all samples were positive for l-tryptophane (IND), d-glucose (GLU), d-mannitol (MAN), and l-arabinose (ARA).
K. ascorbata ATCC 33433 was the only sample positive for trisodium citrate (CIT) fermentation; all other profiles were negative.
301 presumptive + 3 controls.
268 identified + 1 control.