Table 2

Key reactions for biochemical differentiation of selected Enterobacter species
Characteristica 1 2 3 4 5 6 7 8
Voges-Proskauer test (37°C)b + + + - - - + +
Methyl red test + + + + + + - -
Cell morphology SR SR R CR CR CR R R
Ornithine decarboxylaseb - + - - - - + +
Malonate decarboxylase (48 h) + + + - + + - +
Arginine dehydrolaseb + + + - - - + +
Esculin hydrolysis + + + - - + - +
Citrateb + + + + - - + +
Gluconate dehydrogenase + + + - + + - ND
Carbon source utilizationc
   Sucrose + + + - - + + +
   D-melibiose - V - + + + + +
   Adonitol + + - - - - - -
   D-sorbitol + + + - - - + +
   L-fucose + V ND - - - - -
   L-aspartic acid + - + + + + ND ND
   m-inositol + + - - - - + +
   D-arabitol + + - - - + - -
   D-raffinose - + - - - + + +

aFor all strains analysed, the following tests were positive: catalase, β-galactosidase (ONPG) and motility and negative for: oxidase, lysine decarboxylase, urease, indole and H2S production.

bTest results of both the API-20E system and conventional test methods.

cThe carbon source utilization tests were determined by using Biolog GN2 microplates.

*Species: 1, Enterobacter oryziphilus sp. nov. (n=3); 2, Enterobacter oryzendophyticus sp. nov. (n=3); 3, Enterobacter radicincitans D5/23T; 4, Enterobacter turicensis 508/05T; 5, Enterobacter helveticus 513/05T; 6, Enterobacter pulveris 601/05T. 7, Enterobacter cloacae subsp. cloacae; data from [23-25]; 8, Enterobacter cloacae subsp. dissolvens, data from [8,26]. The percentage of strains giving a positive result is scored as: -, 0–20%; V, 20–80%; +, 80–100%; ND, no data available; cell morphology: R, rods; CR, coccoid rods; SR, straight rods.

Hardoim et al.

Hardoim et al. BMC Microbiology 2013 13:164   doi:10.1186/1471-2180-13-164

Open Data