Species differentiation and identification in the genus of Helicobacter

Table 1 Locations, key morphological features and growth characteristics of Helicobacter species colonizing either humans and/or animals

Charastistic	H. pylori	H. canis	H. cinaedi	H.felis	H. fennelliae	H. pullorum	H. westmeadii
Host	Human	Dog, human	Human	Cat,dog, human	Human	Poultry, human	Human
Location	Stomach	Intestine	Blood, rectum	Stomach	Intestine	Intestine	Blood
Cell size (µm)	0.5 × 3.0-5.0	4.0	0.3-0.5 × 1.5-5.0	0.4 × 5-7.5	0.3-0.5 × 1.5-5.0	3 × 4	0.5 × 1.5-2.0
Flagella
Number	4-8	2	1-2	14-20	1-2	1	1
Distribution	Polar	Biopolar	Polar	Biopolar	Polar	Monopolar	Monopolar
Sheath	+	+	+	+	+	-	+
Periplasmic fibers	-	-	-	+	-	-
Growth at:
25 °C	-	-	-	-	-	-	-
37 °C	+	+	+	+	+	+	+
42 °C	-	+	-	+	-	+	-
Growth on:
10 g/Lglycine	-		+	-	+
15 g/L NaCl	-		-	-	-
Tolerance to:
10 g/L bile	-	+	Vary	-	-	+
Safrain ‘O’	-	-	-	-	+	-
Methyl orange	-	-	+	-	Vary	+
Growth under:
Aerobic conditions	-	-	-	-	-	-	-
Microaerobic conditions	+	+	+	+	+	+	Weak+
Anaerobic	Weak+	-	-	+	-	-	+
Susceptibility to:
Nalidixic acid	R	S	S	R	S	S	S
Cephalothin	S	S	I	S	S	R	R
Cefoperazone	S	S	S	S	S	R
Metronidazole	S	S		S