Journal:  Diagnostic Microbiology and Infectious Disease (Elsevier)

Title:  Development of XRM-MacConkey agar selective medium for the isolation of Escherichia albertii.

Authors:  Atsushi Hinenoya, Keigo Nagano, Kentaro Okuno, Akira Nagita, Noritoshi Hatanaka, Sharda Prasad Awasthi and Shinji Yamasaki*

Abstract:  Escherichia albertii has increasingly been recognized as an emerging pathogen. However, lack of selective medium for E. albertii is the bottleneck for clinical and epidemiological investigations. In this study, a selective medium for E. albertii named XRM-MacConkey agar, which is modified MacConkey agar supplemented with xylose (X), rhamnose (R), and melibiose (M) instead of lactose, was developed and evaluated. All 49 E. albertii and 6 different species out of 23 grew as colorless colonies, whereas 17 remaining species grew as red colonies. Detection limit of E. albertii by this medium was 10⁵ CFU/g stool when examined with spiked healthy human stool. Furthermore, colorless colonies on XRM-MacConkey agar obtained from 7 E. albertii–positive diarrheal stools were consistently E. albertii. In contrast, 57%, 18%, and 36% colorless colonies on MacConkey, DHL, and mEA agars, respectively, were non–E. albertii. We concluded that XRM-MacConkey agar could specifically be used for isolation of E. albertii.

新興人獣共通感染症細菌（ヒトの腸管感染症細菌）E. albertiiの分離選択培地XRM-MacConkey寒天培地を開発しました。