TREPONEMA MALTOPHILUM SP-NOV, A SMALL ORAL SPIROCHETE ISOLATED FROM HUMAN PERIODONTAL LESIONS

A novel culture medium for cultivation of fastidious oral anaerobes is described, This medium, OMIZ-Pat, consists of a rich chemically defin ed basal medium supplemented with asialofetuin, as well as yeast extra ct and Neopeptone fractions, Addition of 1 mg of rifampin per liter an d 100 mg of fosfomycin per liter allowed routine isolation of spiroche tes by a limit dilution method in 96-well plates containing liquid OMI Z-Pat. In addition to members of the four previously recognized specie s of oral treponemes (Treponema denticola, Treponema pectinovorum, Tre ponema socranskii, and Treponema vincentii), 26 previously undescribed spirochete strains belonging to one group were isolated, We propose t he name Treponema maltophilum sp, nov, for these small spirochetes, wh ich have two endoflagella; one endoflagellum is attached at each cell pole, and the endoflagella overlap in the middle of the cell, Growth o f these organisms was dependent on a carbohydrate like D-arabinose, L- fucose, D-maltose, L-rhamnose, D-ribose, D-sucrose, or D-trehalose and was inhibited by fetal bovine serum, T. maltophilum is distinguished from other oral Treponema species by its 16S rRNA sequence, its protei n and antigen patterns as determined by sodium dodecyl sulfate-polyacr ylamide gel electrophoresis and immuno-blotting, and its characteristi c alpha-glucosidase activity, The strains included in the new species on the basis of their 16S rRNA sequences are heterogeneous with respec t to their cw-fucosidase and P-glucuronidase activities, their depende nce on N-acetylglucosamine, and their antigens as detected with patien t antibodies, Strain BR is designated the type strain, and strains H02 A and PNA1 are reference strains of the new species.