Lactobacillus nagelii

Genus/species: Lactobacillus nagelii


Gram Stain: Positive


Morphology:

  • Cell: rod-shaped
  • Colony: opaque with smooth edges, 2 mm in diameter
  • Liquid Growth:


Physiological Traits:

  • Facultative anaerobe, tolerates oxygen but can live anerobically.
  • Grows well in CO2 atmosphere
  • Produces DL-lactic acid from glucose but not gas
  • Utilizes citrate or malate in presence of glucose
  • Produces dextran from sucrose
  • No production of mannitol from sucrose nor ammonia from arginine
  • No reduction of nitrate
  • Gelatin is not liquefied, casein is not digested
  • No Indole and no H2S production
  • Ferments many carbohydrates: galactose, glucose, fructose, mannose, sorbose, rhamnose, mannitol, sorbitol, etc.
  • Wide pH tolerance between 3.7-8.0, but sensitive to basic pH, optimal pH 5.5 – 6.2, Temperature tolerant between 15-45oC
  • Oxidase (-), Catalase (-)


Ecological Traits: Ubiquitous in acid environments. Human and animal hosts.


Distinguishing Features:

  • To identify, confirm Rod shape, (-) gas production from glucose, (-) gas from gluconate, (+) presence of meso-DAP in peptidoglycan. Narrows down to 2 species.
  • Closely related to L. mali, but in contrast to L. mali, can ferment maltose and sorbitol, catalase (-), and grew in 5% NaCl w/v at pH 8.


Role in wine: 
L. nagelii may be responsible for slowing wine fermentations. Like other Lactobacillus spp. may be considered a wine spoilage organism due to the production of acetic acid and other off flavors. Primarily observed as a contributor to malolactic fermentation.


Sensitivities:

  • SO2: Sensitive
  • Sorbate: Unknown
  • DMDC: Unknown
  • pH: Seinsitve to basic pHs
  • Acids: No
  • Ethanol: Senstive
  • Anaerobiosis: No
  • Heat: Sensitive
  • Antiobiotic sensitivity, i.e. penicillin, erythromycin, tetracycline…
  • Aciduric/acidophilic. Maximum for growth pH is approx. 7.2

References:
Edwards C., M. Collins, P. Lawson, A. Rodriguez. 2000. Lactobacillus nagelii sp. nov., an organism isolated from a partially fermented wine. International Journal of Systematic and Evolutionary Microbiology. 50, 699-702.

Tags

Bacteria