Identification of Streptobacillus moniliformis isolated from the knee joint pus by 16S rRNA gene sequencing and biochemical reactions / 实用医学杂志

ABSTRACT

Objective To indentify Streptobacillus moniliformis isolated from the knee joint pus by 16S rRNA gene sequencing and biochemical reactions and explore the clinical value of the method. Methods The bacterial 16S rRNA gene sequence-based identification, bacterial morphology, VITEK 2 automate systems, API 20NE strips, API 20E strips and API 50CH were performed to identify the rare bacteria. Results The bacteria grew slow on blood agar and chocolate agar and were inhibited on Maconkey agar. The bacterial colony on blood agar tookes the form of 1~2 mmomelette, which was translucent and moist with circular protrusion and smooth edges. They were Gram-staining negative and in catenation, its thalli 1~3μm, round, oval or fusiform. Vitek 2 GN-13, API 20NE and API 20E were unable to reach the identification of the bacteria. 16S rRNA gene sequencing showed the bacteria were similar to streptobacillus moniliformis by 100%. Conclusion The rare bacteria isolated from left knee joint are streptobacillus moniliformis. 16S rRNA gene sequences combined with the biochemical reactions is accurate in the identification of these bacteria.