The Genera Chromobacterium and Janthinobacterium

Table 1. Characteristics differentiating the groups of violacein-producing organisms.

Character	Chromobacterium	Janthinobacterium	Iodobacter [Chromobacterium] fluviatilis
Growth at 4°C	−	+ (96%)^a	+
Growth at 37°C	+	−	−
Fermentation of glucose (O/F test)	F^b	0^c (90%)	F
Anaerobic growth	+	− (96%)	+
Cyanide produced	+	−	−
Turbid zone on egg yolk agar (lecithinase)	+	−	(+)^d
Acid from
Trehalose	+	− (82%)	+
L-arabinose	−	+	−
D-cellobiose	−	+ (99%)	−
D-galactose	−	+ (96%)	−
Gluconate	+	− (99%)	+ (96%)
D-maltose	−	+ (96%)	+
N-acetylglucosamine	+	− (99%)	+
Lactate utilization	+	+ (99%)	−
Casein hydrolysis	+	− or (+)	+
Esculin hydrolysis	−	+ (80%)	−
Arginine decarboxylase	+	−	−
GC content (mol%)	65–68	65–66	50–52

^aNumbers in parentheses indicate the % of strains giving the indicated reaction.
^bF, fermented.
^cO, oxidized.
^d(+) weakly positive.
The phenotypic data are from Sneath (1984), Moss et al. (1978) and Logan (1989). The GC values are from De Ley et al. (1978) and from Moss et al. (1978) for Iodobacter [Chromobacterium] fluviatilis.