i^AMiLY NEISSERIACEAE 295 



FAMILY VI. NEISSERIACEAE PREVOT.* 



(Ann. Sci. Nat., Ser. Bot., 15, 1933, 119.) 



Cells spherical, in pairs or in masses. Non-motile. Gram-negative. Pigment 

 formation rare. The family contains aerobic and anaerobic species. Some grow poorly 

 or not at all without mammalian body fluids. Optimum temperature 37°C. All 

 known species are parasitic. 



Key to the genera of family Neisseriaceae. 



I. Occurring in pairs, with adjacent sides usually flattened. Aerobes, faculta- 

 tive anaerobes and anaerobes. Approximately 1 micron in diameter. 



Genus I. Neisseria, p. 295. 

 II. Occurring in masses, rarely in pairs. Anaerobes. Less than .5 micron in 

 diameter. 



Genus II. Veillonella, p. 302. 



Genus I. Neisseria Trevisan. 



(Trevisan, Atti della Accademia Fisio-Medico-Statistica in Milano, Ser. 4, 3, 1885, 

 105; Gonococcus Lindau (?), Just's Bot. Jahresber., I Abt., Orig., 26, 1898, 100.) 

 Named for Dr. Albert Neisser who discovered the organism causing gonorrhoea in 1879. 



Paired, Gram-negative cocci with adjacent sides flattened. Four of the eleven 

 species produce yellow pigment. Aerobic and anaerobic species occur. Growth on 

 standard media may be poor. Biochemical activities are limited. Few carbohy- 

 drates are utilized. Indole is not produced. Nitrates are not reduced. Catalase is 

 produced abundantly. Parasites of mammals so far as known. 



The type species is Neisseria gonorrhoeae Trevisan. 



Key to the species of genus Neisseria. 



I. Aerobes, facultative anaerobes. 



A. Grow best on special culture media or on plain agar containing blood, blood 



serum or similar enrichment fluids, especially with added glucose. 

 Grow best at 35° to 37°C; no growth below 25° or above 40°C. Not 

 chromogenic. 



1. Acid from glucose, not from malto.se. Growth anaerobically. 



1. Neisseria gonorrhoeae. 



2. Acid from glucose and maltose. No growth anaerobically. 



2. Neisseria meningitidis. 



B. Grow well on ordinarj^ culture media. Grow well at 22°C. 

 1. Non-chromogenic. 



a. Moist colonies on agar. No action on glucose, sucrose or mannitol. 



3. Neisseria catarrhalis. 



aa. Dry crumbly colonies on agar. Acid from glucose and sucrose; 

 but not from mannitol. 



4. Neisseria sicca. 



* Revised by Prof. E. G. D. Murray, McGill University, Montreal, P.Q., Canada 

 in consultation with Dr. Sara E. Branham, United States Public Health Service, 

 Washington, D. C, June, 1938; further revision, August, 1943. Descriptions of 

 anaerobic species reviewed by Dr. Ivan C. Hall, New York City, January, 1944. 



