PHYLOGENY OF SPECIES IN THE FAMILY NEISSERIACEAE ISOLATED FROM HUMAN DENTAL PLAQUE AND DESCRIPTION OF KINGELLA-ORALE SP-NOV

Fourteen human periodontal isolates recovered from a purported Eikenel la corrodens-selective medium containing 1 mug of clindamycin per ml d isplayed biochemical traits which differed from those described for E. corrodens. These organisms were gram-negative rods which corroded aga r. The isolates were oxidase positive and urease, indole, and esculin negative. They differed from E. corrodens in catalase, nitrate reducti on, lysine decarboxylase, and ornithine decarboxylase activities. One isolate, strain UB-294, was presumptively identified as Kingella denit rificans. A second isolate, strain UB-204, differed from E. corrodens by being catalase positive and nitrate reduction negative. Twelve isol ates, including strain UB-38 T (T = type strain), were phenotypically similar to Kingella kingae except that they did not produce acid from maltose and were not beta-hemolytic. Essentially complete (1,480-base) 16S rRNA sequences were determined for strains UB-38T, UB-204, and UB -294 and the type strains of Neisseria animalis, Neisseria canis, Neis seria denitrificans, Neisseria elongata, Neisseria flavescens, Neisser ia macaca, and Neisseria polysaccharea. These sequences were compared with the previously published sequences of six other species belonging to the family Neisseriaceae. On the basis of the results of the compa rative sequence analysis, UB-294 was confirmed as a K. denitrificans s train, UB-204 was identified as a member of a new species which may be long in the genus Eikenella, and UB-38T was identified as a member of a new species of the genus Kingella, for which we propose the name Kin gella orale. Since strain UB-204 was the only representative of a new species, it was not named. DNA probes for identification of E. corrode ns, K. denitrificans, and K. orale based on 16S rRNA sequence informat ion are described.