Neisseria 219831 220810309 2008-06-21T18:15:59Z 79.10.116.232 {{Taxobox | color = lightgrey | name = ''Neisseria'' | image = Neisseria_gonorrhoeae_02.png | image_width = 240px | image_caption = Fluorescent antibody stain of ''Neisseria gonorrhoeae''. | regnum = [[Bacterium|Bacteria]] | phylum = [[Proteobacteria]] | classis = Beta Proteobacteria | ordo = [[Neisseriaceae|Neisseriales]] | familia = [[Neisseriaceae]] | genus = '''''Neisseria''''' | genus_authority = Trevisan, 1885 }} '''''Neisseria''''' is a genus of Gram (-) [[bacterium|bacteria]] included among the [[proteobacteria]], a large group of [[Gram-negative]] forms. ''Neisseria'' are [[Diplococcus|diplococci]] that resemble coffee beans when viewed microscopically.<ref name=Sherris>{{cite book | author = Ryan KJ; Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 | id = ISBN 0-8385-8529-9 }}</ref> The genus includes the species ''[[Neisseria gonorrhoeae|N. gonorrhoeae]]'' (also called the ''gonococcus''), which causes [[gonorrhoea]], and ''[[Neisseria meningitidis|N. meningitidis]]'' (also called the ''meningococcus''), one of the most common causes of bacterial [[meningitis]] and the causative agent of meningococcal [[septicaemia]]. This genus also contains several, believed to be nonpathogenic species, like: *''[[Neisseria cinerea]]'' *''[[Neisseria elongata]]'' *''[[Neisseria flavescens]]'' *''[[Neisseria lactamica]]'' *''[[Neisseria mucosa]]'' *''[[Neisseria polysaccharea]]'' *''[[Neisseria sicca]]'' *''[[Neisseria subflava]]'' ==History== The [[genus]] ''Neisseria'' is named after the German bacteriologist [[Albert Neisser]], who discovered its first example, ''Neisseria gonorrheae'', the pathogen which causes the human disease [[gonorrhea]]. Neisser also co-discovered the pathogen that causes [[leprosy]], ''[[Mycobacterium leprae]]''. These discoveries were made possible by the development of new staining techniques which he helped to develop. ==Biochemical Indentification== All the medically significant species of ''Neisseria'' are positive for both [[catalase]] and [[oxidase]]. Different ''Neisseria'' species can be identified by the sets of sugars from which they will produce acid. For example, ''N. gonorrheae'' makes acid from only glucose, however ''N. meningitidis'' produces acid from both glucose and maltose. '''Polysaccharide capsule''' ''N. meningitidis'' has a polysaccharide capsule that surrounds the outer membrane of the bacterium and protects against soluble immune effector mechanisms within the serum. It is considered to be an essential virulence factor for the bacteria. ==References== {{Reflist|2}} [[Category:Proteobacteria]] {{Proteobacteria-stub}} [[ca:Neissèria]] [[de:Neisseria]] [[es:Neisseria]] [[eu:Neisseria]] [[fr:Neisseria]] [[he:Neisseria]] [[it:Neisseria]] [[sr:Најсерије]] [[sv:Neisseria]] [[tr:Neisseria]] [[zh:奈瑟菌屬]]