TABLE 3.

Differential phenotypic characteristics of H. bizzozeronii, H. felis, H. salomonis, and “F. rappini”-like strains examined

Characteristica	% of strains of indicated species positive for the characteristic
	H. bizzozeronii (n = 10)	H. felis (n = 16)	H. salomonis (n = 6)	“F. rappini”-like (n = 2)
Cell morphology
Tightly coiled spiral	78	67	0	0
Loosely coiled spiral	33	7	17	100
Vibrioid/coccoid forms	20	40	83	0
Oxidase	90	100	100	100
Urease	80	94	100	50
Alkaline phosphatase	50	62.5	50	100
Indoxyl acetate hydrolysis	20	25	17	0
TTC reduction	0	12.5	0	100
Anaerobic growth on BA	30	56	67	100
Anaerobic growth on TMAO	0	25	33	100
Growth at 37°C	90	100	67	100
Growth at 42°C	60	50	0	0
Growth on:
Potato starch medium	0	6	17	99
Lecithin medium	0	12.5	0	0
Tolerance to:
1, 1.5, and 2% bile	0	0	0	100
1% glycine	10	6	0	0
0.04% TTC	0	12.5	0	100
Nalidixic acid, 32 mg/liter	0	6	0	0
Cephalothin, 32 mg/liter	10	19	50	100
Metronidazole, 4 mg/liter	0	12.5	17	0
Carbenicillin, 32 mg/liter	10	19	33	0
Cefoperazone, 64 mg/liter	0	6	0	0
5-Fluorouracil, 100 mg/liter	80	75	17	100
0.05% sodium fluoride	20	31	33	0

^aBA, blood agar; TMAO, trimethylamine N-oxide medium; TTC, triphenyl tetrazolium chloride.