Genus/species: Gluconacetobacter europaeus since 1998 (Ga. europaeus) (Acetobacter europaeus prior to 1998).
Gram Stain: Negative
Morphology:
Cell: non-motile and non-flagellated rods. Most occur in pairs
Colony: in the presence of CaCO3 a zone of clearing will be obvious around the colonies dues to the neutralization of the acid generated.
Liquid Growth:
Physiological Traits:
- The bacteria are extremely resistant to high acetic acid concentrations, up to 10 % v/v.
- Carbon sources: n-propanol, fructose, maltose, sucrose, glycerol, sorbitol, and mannitol.
Ecological Traits:
Important part of the vinegar production in Europe.
Distinguishing Features:
- Produces acetic acid from ethanol
- Grows in acetic acid at pH 2.5
- Will not utilize glycerol, gluconate or lactate.
Role in wine:
- Oxidases ethanol to acetic acid; causing the spoilage of wine.
Sensitivities:
SO2: >100mg/L
Sorbate: No
DMDC: Unknown
pH: Highly adaptable to changes in pH.
Acids: Highly tolerant
Ethanol: Mixed results (none specific for bacteria)
Anaerobiosis: Obligated aerobes
Heat: intolerant