First isolations of Levinea-Citrobacter cultures in Czechoslovakia.

Twenty-two strains corresponding by their biochemical properties to the genus Levinea - Citrobacter were isolated. Six of the strains were referred to the species Citrobacter diversus and 12 to C. freundii, whose properties are identical with those of L. malonatica and L. amalonatica, respectively. Four strains differed from Levinea organisms by some reactions, but were fully compatible with C. freundii (in the scheme of EWING and DAVIS); two of them utilized malonate. The taxonomic position of strains displaying the following biochemical properties: dextrose positive, indole positive, H2S negative, urease on Christensen's citrate medium positive, lysine-decarboxylase negative-is discussed. In routine practice, these strains may be more accurately identified by adding of four tests: adonitol with gas production, KCN, raffinose and malonate.