We, the RIKEN BioResource Center, regret to inform you that the freeze-dry ampoule of strain JCM 1043 contained contaminated microorganisms.
JCM 1043 was registered in 1982 and has been distributed since then. During the course of our quality test, we recently detected the presence of slowly growing contaminated microorganisms in the culture of the lot-3 ampoule made in 2005. We did not detect any contamination in the lot-1 and lot-2 ampoule distributed before 2005. We have made the new ampoule that we confirmed purity and authenticity of the strain, and now, it is available upon request.
It is often difficult to detect such slowly growing contaminated microorganisms. However, we will do our best for testing the purity by extending the culturing period after the authentic strain grows, in order to improve the quality of our microbial resources. We ask you for your understanding and continuous support.
We have sent notes to all past users of the lot-3 ampoule of JCM 1043 by February 16, 2015, expressing our sincere apology and explaining this matter.
If you have any question and concern on this matter, please feel free to contact us (inquiry.jcmriken.jp).