The name derives from вЂњmyxoвЂќ (Greek for slime) and вЂњfaciensвЂќ (Latin for producing). It produces slime and is not known to have been isolated from a human. In 1966, Cosenza and Podgwaite described another new species, Proteus myxofaciens, that they isolated from the larvae of the gypsy moth ( 19). mirabilis, an alternative classification that was not long-lived ( 56). It should be noted that in 1952 Kauffmann and Edwards published a taxonomic table listing вЂњ Proteus hauseriвЂќ var. mirabilis fermented glucose readily and sucrose slowly and did not ferment maltose. vulgaris fermented glucose, sucrose, and maltose readily, while P. The ability to ferment glucose, sucrose, and maltose served as a means to further subdivide the strains into two groups, as Hauser had done. All of these strains also produced hydrogen sulfide and were lactose nonfermenters. Consistent with Hauser's work of 1885, their strains also swarmed and liquefied gelatin. In 1919, Wenner and Rettger in Connecticut were studying the biochemical characteristics of a larger group of Proteus strains ( 108). vulgaris compared to other then-known enteric organisms. The previous year, he had demonstrated the unusually small amount of gas produced from glucose by P. In 1894, Theobald Smith reported the fermentative characteristics of the two species using glucose, sucrose, and lactose and their greatly diminished or complete loss of the ability to liquefy gelatin as the culture aged ( 93). Hauser also described вЂњ Proteus zenkeri,вЂќ which neither swarmed nor liquefied gelatin, but he rescinded this particular finding 7 years later ( 43). vulgaris liquefies gelatin вЂњrapidly,вЂќ and P. He noted the swarming nature of the organisms and divided the strains into the two species based on the speed of their ability to liquify gelatin: P. vulgaris, both first described by Hauser in 1885 ( 42). The term Proteus means вЂњchangeability of form, as personified in the Homeric poems in ProteusвЂ‰вЂ¦вЂ‰and has the gift of endless transformationвЂќ ( 108). The literature abounds with studies on the taxonomy of the genus Proteus since the original publication by Hauser, who first described the genus (Table вЂ‹ (Table1) 1) ( 42). hauseri) and three unnamed genomospecies ( Proteus genomospecies 4, 5, and 6). The genus Proteus currently consists of five named species ( P. Proteus rettgeri becomes Providencia rettgeri alcalifaciens redescribed as Providencia alcalifaciens with second subgroup named P. Providence group renamed Proteus stuartiiД«acillus inconstans renamed Proteus inconstansД®. Providence group named Providencia providenciae rettgeri as Proteus rettgeriДЄnaerogenic paracolon 29911 designated Providence group

Many of these organisms are easily controlled, but some problems have arisen with the advent of newer and more powerful antimicrobial agents. Lastly, anticipated antimicrobial susceptibility patterns will be considered. While all of these organisms are ubiquitous in the environment, individual case reports and nosocomial-outbreak reports indicate that they are capable of causing major infectious disease problems. Their clinical significance will also be discussed. In this review, the evolution of the вЂњfamily treeвЂќ of Proteus, Providencia, and Morganella will be discussed within each genus, along with the current methods for the identification of each species of the genus, incorporating both conventional biochemical and commercial methods. It is clear that while the more pathogenic members of the Enterobacteriaceae, such as Salmonella, Shigella, and Escherichia coli, may exact more urgent attention, the presence of any one of these less pathogenic genera in body fluids and in some deep or superficial lesions would lead one to suspect their potential etiologic nature. As with other opportunistic pathogens, they may also cause morbidity and mortality. Species within these genera are not considered frank pathogens, unlike some of the other members of the Enterobacteriaceae, and are commonly isolated in clinical laboratories. The taxonomy of Proteus, Providencia, and Morganella is a fascinating story that is enmeshed throughout the early history of the evolving science of microbiology.

Proteus 2000