Multivariate analyses of cellular fatty acids and carbohydrates of 1:2:1 and 2:4:2 spirochetes

Abstract

Delimitation of small‐sized spirochetes of the oral cavity can be difficult. The endoflagella pattern has long served as the main criterion for taxonomic distinction. For approved species, e.g. Treponema denticola, several endoflagella patterns are observed, which indicates that this criterion is inadequate. The present study with GC and GC‐MS used fatty acids and carbohydrates of whole‐cell methanoly‐sates to distinguish 1:2:1 and 2:4:2 subgingival spirochetes. Thirteen fatty acids: C_12:0, C_13:0, C_14:0, C_iso‐14:0, C_{2‐OH‐14:0}, C_15:0, C_antc‐15:0, C_16:0, C_iso‐16:0, C_16:1, C_18:0, C_18:1, and C_18:2, and three carbohydrates: rhamnose, glucose, and glucosamine, were detected. The carbohydrate contents did not differ between the two groups. While 1:2:1 spirochetes contained C_iso‐14:0 and C_antc‐15:0 acid, 2:4:2 spirochetes did not. Also multivariate analyses of quantitative fatty acid data distinguished between these groups.