Neisseria elongata
Acid from glucose
Nitrate reduction
N. elongata subsp. elongata
- / weak +
N. elongata subsp. glycolytica
weak +
N. elongata subsp. nitroreducens
weak +
Differential characters of Neisseria elongata subspecies:
Colonies are semi-opaque to grayish white with a yellowish tinge due to pigment
production. Older colonies may attain a diameter of 4-5 mm and often show granular
spreading zones around the periphery, or the colonies become irregular in outline
with spreading projections. The colony texture is usually clay-like and coherent, and
the growth mass when collected is lumpy and diffcult or impossible to disperse.
Colonies on blood agar are non-hemolytic, shiny and low convex with an entire edge,
2-3 mm in diameter after 48 h of incubation. Agar corrosion with a peripheral groove
and a central pit may be observed.
N. elongata subsp. glycolytica produce soft, homogenous, and easily emulsifiable
Optimal growth temperature 33–37 ºC. Aerobic; weak growth under anaerobic
conditions. Grows on simple peptone media.
Cultural characteristics
Biochemical characters
Phylum Proteobacteria, Class Betaproteobacteria, Order Neisseriales, Family Neisseriaceae, Genus Neisseria, Neisseria elongata
Bovre and Holten 1970.
- Neisseria elongata subsp. elongata (Bovre and Holten 1970) Henriksen and Holten 1976;
- Neisseria elongata subsp. glycolytica Henriksen and Holten 1976;
- Neisseria elongata subsp. nitroreducens Grant et al. 1991.
Gram-negative short rods 0.5 µm wide, often arranged as diplobacilli or in chains. Some organisms may be coccoid, which change
uniformly into long threadlike filaments by culture in the presence of low concentrations of penicillin. Often fimbriated. Non-motile.
Capsule is not produced.
Isolated from the pharynx of healthy individuals and from cases of pharyngitis. Also isolated from bronchial aspirates, pus from
perimandibular abscesses, blood cultures during endocarditis, and urinary tract. Not animal isolates reported.
- N. elongata subsp. elongata was first isolated from the nasopharynx of a presumably healthy person in northern Norway.
- N. elongata subsp. glycolytica was isolated from the throat of a patient with pharyngitis. Susceptible to  penicillin, streptomycin,
chloramphenicol, tetracyclines, and erythromycin.
- N. elongata subsp. nitroreducens was found in throat or sputum and from blood, with many of the systemic isolates being
associated with endocarditis.
Undetermined. May be involved in endocarditis or pharyngitis.
  1. Tone Tonjum, 2005. Order IV. Neisseriales ord. nov. In:  Bergey’s Manual of Systematic Bacteriology, Second edition, Vol two, part C
    The Alpha-, Beta-, Delta-, and Epsilonproteobacteria, George M. Garrity (Editor-in-Chief), pp 774-863.
  2. K. Bovre, E. Holten: Neisseria elongata sp.nov., a Rod-shaped Member of the Genus Neisseria. Re-evaluation of Cell Shape as a
    Criterion in Classification. Microbiology, January 1970 60: 67-75.
  3. S. D. Henriksen, E. Holten: Neisseria elongata subsp. glycolytica subsp. nov. Int J Syst Evol Microbiol, October 1976 26: 478-481.
  4. Paul A. Lawson, Henry Malnick, Matthew D. Collins, Jayesh J. Shah, Marie A. Chattaway, Richard Bendall, and John W. Hartley:
    Description of Kingella potus sp. nov., an Organism Isolated from a Wound Caused by an Animal Bite. J. Clin. Microbiol. July 2005
    43:7 3526-3529; doi:10.1128/JCM.43.7.3526-3529.2005.
Positive results for carbonic anhydrase, nitrite reduction, gas production from nitrite & oxidase.

Negative results for DN-ase, beta-galactosidase, gelatin hydrolysis, indole production, H
2S production, liquefaction of coagulated
serum, phenylalanine production, tributyrin hydrolysis, iodine test (polysaccharide synthesis from sucrose), urease, acid production
from: fructose, lactose, maltose, mannose & sucrose.
(c) Costin Stoica
Culture media
Biochemical tests
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