The Biochemical and Serological Relationships of the Organisms of the GenusProteus

Abstract

454 Proteus cultures were studied in detail and > 2000 additional cultures were observed routinely. Strong urease production in 8-48 hrs. in highly buffered medium and failure to ferment lactose are the best generic criteria. P. vulgaris, P. mirabilis and P. morganii produced small gas volumes in fermentable carbohydrates and an occasional anaerogenic strain was encountered, particularly among old stock cultures. P. rettgeri is usually anaerogenic. P. vulgaris ferments glucose, sucrose and maltose rapidly, is mannitol negative, produces indole and H2S and liquefies gelatin. P. mirabilis ferments glucose rapidly and sucrose slowly, is maltose and mannitol negative, produces indole but not H2S and does not liquefy gelatin. P. rettgeri ferments glucose and mannitol rapidly and sucrose slowly, is maltose negative, produces indole but not H2S and fails to liquefy gelatin. Antigenic analyses revealed a marked continuity of antigens among the strains within each species with some overlapping antigens between the different spp. Despite this antigenic continuity, anti-genically identical Proteus cultures were seldom found. Antigenic typing as with Salmonella and Shigella appears to be impracticable with Proteus.