Genus/species: Acetobacter peroxydans
Gram Stain: Negative
Morphology:
- Cell: Rod-shaped, 2-3 μm long and about 0.5 μm in width. Many diplobacters, which are very motile during the first few minutes on the slide.
- Colony: Slants on beer-gelatine at 20 °C. Grows well on standard medium (MYP). Slightly echinulate, sometimes beaded, luster glistening and the consistency butyrous. Color varies by strain from predominantly pale brown to white. None of the strains liquefied gelatin.
- Liquid Growth: Unknown
Physiological Traits:
Strictly aerobic. Temperature optimum is 20-25 °C. Grows readily on ethanol, lactate, or on yeast extract alone, but not on carbohydrates and derivatives. Unable to metabolize any sugars. Resting cells readily oxidize DL-lactate, pyruvate, ethanol, acetate, some Krebs cycle intermediates, and several alcohols. Cell-free extracts oxidize glucose-6-phosphate, 6-phophogluconate and ribose-5-phosphate in suitable conditions.
Ecological Traits:
Has been isolated in ditch water, sewage, sugar beet pulp, and one strain has been isolated in wine.
Distinguishing Features:
Catalase negative but hydrogen peroxide can be reduced using hydrogen and strains are therefore peroxidase positive. Unable to metabolize any carbohydrate or derivative. All strains are acid resistant. All strains produce acetic acid in a medium containing 1% Difco yeast extract, 2% ethanol. After one week to ten days all the acid is consumed again. None of the strains are able to grow as hydrogen bacteria.
Role in wine:
Very little is known from literature reviews. Only one strain has been isolated as a spoilage organism in wine (1925).
Sensitivities:
- SO2: unknown
- Sorbate: unknown
- DMDC: unknown
- pH: > 6.0
- Acids: no
- Ethanol: no
- Anaerobiosis: no
- Heat: > 40 °C
References:
- Bergey’s Manual of Systematic Bacteriology: Volume Two The Proteobacteria Part C The Alpha-, Beta-, Delta-, and Epsilonproteobacteria. 2005. Springer, New York.
- De Ley, J. 1958. Studies on the metabolism of Acetobacter peroxydans. Part I. – General properties and taxonomic position of the species. Antoine van Leeuwenhoek. 24:281-297.