Lactobacillus jensenii

Genus/species: Lactobacillus jensenii

Gram Stain: Positive

Morphology:

  • Cell: rod-shaped, 0.6-0.8 m x 2.0-4.0, Single or short chains, non-spore forming
  • Colony: small, smooth, circular, translucent, non-pigmented      
  • Liquid Growth:

Physiological Traits
Grows on Blood agar, facultatively heterofermentative; prefers no O2 but can tolerate small amounts of oxygen; grows in presence of 1.5% NaCl but not 3% NaCl. Lactic acid produced from glucose without gas. Catalase- and Oxidase- negative, Produces H2O2

Ecological Traits: 
Found mainly in lower female genital tract.  Composes 23% of natural vaginal microflora.  Found on grapes at time of harvest.


Distinguishing Features:

  • Hydrolysis of arginine
  • Production of D-lactate (only)
  • Readily ferments amygdalin, cellobiose, galactose, D-mannose, salicin, sucrose, and trehalose. (11-90% of strains can ferment arabinose, esculin, gluconate,  maltose, mannitol, melibiose, ribose, and sorbitol)
  • Cannot ferment lactose, melexitose, mannitol, sorbitol, arabinose, or xylose
  • Presence of meso-DAP in peptidoglycan.


Role in wine:  
Lactobacillus jensenii can metabolize sorbate in wine and produce off-odors that contribute a “geranium odor.”


Sensitivities:

  • SO2:Yes. pH dependent
  • Sorbate: Can metabolize
  • DMDC: Yes; >50 ppm
  • pH: Present in greater concentrations above pH 3.5
  • Acids: No data
  • Ethanol: In one study different species within Lactobacillus show widely varying tolerances to EtOH
  • Anaerobiosis: Sensitive to O2; in presence of O2 acetate is formed rather than lactate
  • Heat: Can tolerate temperatures up 45º C


References:

  • Edinger, W.D. and D.F. Splittstoesser. Sorbate tolerance by lactic acid bacteria associated with grapes and wine.  J. Food Sci. 51:1077-1078. (1986)
  • Gold, R.S., M.M. Meagher, R. Hutkins, and T. Conway. Ethanol tolerance and carbohydrate metabolism in lactobacilli. J. Ind. Microbiol. 10:45-54. (1992)