Neisseria

Group of bacteria that includes the cause of gonorrhea.

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A genus of aerobic bacteria (family Neisseriaceae) containing Gram-negative cocci which occur in pairs with the adjacent sides flattened. These organisms are parasites of animals. The type species is N. gonorrhoeae. [A. Neisser]

- N. catarrhalis former name for Moraxella catarrhalis.

- N. caviae a bacterial species found in the pharyngeal region of guinea pig s; may also be found in other animals.

- N. flava a bacterial species found in the mucous membranes of the human respiratory tract; easily confused with N. meningitidis. SYN: N. subflava.

- N. flavescens a bacterial species found in cerebrospinal fluid in cases of meningitis; probably occurs in the mucous membranes of the human respiratory tract.

- N. gonorrhoeae a bacterial species that causes gonorrhea and other infections in humans; the type species of the genus N.. SYN: gonococcus, Neisser coccus.

- N. haemolysans former name for Gemella haemolysans. See Gemella.

- N. meningitidis a bacterial species found in the nasopharynx of humans but not in other animals; the causative agent of meningococcal meningitis and meningicoccemia; virulent organisms are strongly Gram negative and occur singly or in pairs; in the latter case the cocci are elongated and are arranged with long axes parallel and facing sides kidney shaped; groups characterized by serologically specific capsular polysaccharides are designated by capital letters (the main serogroups being A, B, C, and D). SYN: meningococcus, Weichselbaum coccus.

- N. sicca a bacterial species found in the mucous membranes of the human respiratory tract.

- N. subflava SYN: N. flava.

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Neis·se·ria nī-'sir-ē-ə n a genus (the type of the family Neisseriaceae) of parasitic bacteria that grow in pairs and occas. tetrads, thrive best at 98.6°F (37°C) in the animal body or serum media, and include the gonococcus (N. gonorrhoeae) and meningococcus (N. meningitidis)

Neis·ser 'nī-sər Albert Ludwig Sigesmund (1855-1916)

German dermatologist. Neisser discovered the bacillus that causes gonorrhea in 1879. In 1885 the genus Neisseria, named in his honor, was described, and this microorganism and related bacteria were placed in it.

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n.

a genus of spherical Gram-negative aerobic nonmotile bacteria characteristically grouped in pairs. They are parasites of animals, and some species are normal inhabitants of the human respiratory tract. The species N. gonorrhoeae (the gonococcus) causes gonorrhoea. Gonococci are found within pus cells of urethral and vaginal discharge; they can be cultured only on serum or blood agar. N. meningitidis (the meningococcus) causes meningococcal meningitis. Meningococci are found within pus cells of infected cerebrospinal fluid and blood or in the nasal passages of carriers. They too can only be cultured on serum or blood agar.

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Neis·se·ria (ni-seґre-ə) [A.L.S. Neisser] a genus of bacteria of the family Neisseriaceae, consisting of gram-negative, oxidase-positive cocci characteristically coffee bean–shaped and paired. The organisms are aerobic or facultatively anaerobic and are part of the normal flora of the oropharynx, nasopharynx, and genitourinary tract. The genus includes the gonococcus, the several meningococcus types, pigmented forms occasionally associated with meningitis, and a number of saprophytic or parasitic but nonpathogenic species. The type species is N. gonorrhoeґae.