''Moraxella lacunata'' is a rod-shaped,

Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

, nonmotile bacterium, generally present as

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...

pairs. It causes one of the commonest forms of catarrhal

conjunctivitis Conjunctivitis, also known as pink eye, is inflammation of the conjunctiva, outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may ...

History

''Moraxella lacunata'' was first described independently by

Victor Morax Victor Morax, Paris, 1920 Victor Morax (16 March 1866 – 14 May 1935) was an ophthalmologist born in Morges, Switzerland. He studied in Freiburg (Germany) and Paris, and from 1891 to 1903, he worked at the Pasteur Institute in Paris. From 19 ...

(1896) and

Theodor Axenfeld Karl Theodor Paul Polykarpus Axenfeld (24 June 1867 – 29 July 1930) was a German ophthalmologist born in Smyrna (İzmir) in the Ottoman Empire to a German minister, who was a Jewish convert to Christianity and served as missionary in Asia Minor. ...

(1897), hence the alternate name "Morax-Axenfeld diplobacilli" and the name of eye infection in humans is sometimes called Morax-Axenfeld conjunctivitis.

Characters

It has the ability to change its

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

in laboratory. '' M. lacunata'' became shorter and tended to lose its Gram-negative staining characteristic when left out for 5 days. It also tended to retain these new characteristics on subsequent blood-agar transfers.

Clinical significance

Infection occurs mainly in adults, but can occur at any age. It is characterized by: * Chronic, mild angular blepharoconjunctivitis frequently localized on the lid at the outer

canthus The canthus (pl. canthi, palpebral commissures) is either corner of the eye where the upper and lower eyelids meet. More specifically, the inner and outer canthi are, respectively, the medial and lateral ends/angles of the palpebral fissure. Th ...

* Typical

erythema Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not assoc ...

of the edges of the lids * Slight maceration of the skin, most marked at the angles, especially the outer canthus * Superficial infiltration of the cornea is not uncommon. * The discharge is grayish yellow, adherent to the lashes, and accumulates mainly at the angles.

References

External links

Type strain of ''Moraxella lacunata'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
Gram-negative bacteria Moraxellaceae {{Pseudomonadales-stub