Characterization of treponemes isolated from human and non‐human primate periodontal pockets

Treponemes were isolated from ligature induced periodontal pockets of non‐human primates, and from humans with periodontitis. Approximately 39% of the microscopic count were spirochetes from humans, while 65% of the microscopic microbiota was accounted for by spirochetes from non‐human primates. Metabolically, the human treponemal isolates grew on trypticase‐yeast extract based media while the non‐human primate isolates grew only on pectin, glucuronic or galacturonic acids. The end‐products of glucose fermentation by the human treponemes were acetate and propionate, while acetate was produced by the non‐human primate treponemes from pectin. All of the human isolates were indole positive, hemolyzed blood, required serum for growth, but did not require thiamine pyrophosphate (TPP). The non‐human primate treponemes were indole negative, were inhibited in their growth by blood, grew in the absence of serum, and required TPP for growth. PAGE analysis of whole cell proteins revealed three categories of treponemal isolates: (i) human isolates similar to Treponema denticola; (ii) human isolates of small size; and (iii) non‐human primate isolates similar to the pectinolytic treponemes. Serologically, the human treponemal isolates were similar to T. denticola, while the non‐human primate isolates were similar to the pectinolytic treponemes. Four human, 4 non‐human primate, and 4 reference treponemes exhibited a Mol% G + C of their DNA of 40.0‐43.1. The metabolic differences between the human and non‐human primate treponemal isolates may be a reflection of ecological differences in the periodontium of the pathological entities which exist in human and non‐human primates.