Since 1967, culture collection of bacterial pathogen started at RIMD which at first belonged to the Department for Bacterial Serology. A culture collection room was established independently in RIMD supported by the Ministry of Education in 1973. It was reorganized as the Research Center for Emerging Infectious Diseases in 1998. Furthermore, in 2005 it was reorganized as the Pathogenic Microbes Repository Unit in the International Research Center for Infectious Diseases. The author worked as curator with a technician to maintain and develop the collection. A description is presented here of the history of our culture collection and the research being conducted to develop a high-quality collection at the Unit.

Recent large-scale food poisoning related incidents have raised consumer awareness and demand for greater food safety. Food companies have introduced various monitoring and methods of control, and continuous action is being taken to ensure the safety of food. Against this background, test methods for detection and discrimination of microbes have progressed; however, there has long been a need for a rapid and accurate method to identify various microbes. Thus, since 1997, my colleagues and I have been in the process of developing an identification method for aerobic endospore-forming bacteria, which is more rapid, accurate, unified, and time-efficient than previous methods.

For a number of years, contamination and spoilage by aerobic endospore-forming bacteria has been a serious quality issue in the food industry. However, the taxonomy of the bacteria is very complex, there are many genera and species, and it is difficult to find differential characteristics among the bacteria for accurate identification. Accordingly, we evaluated and developed an identification method based on the 16S rDNA sequence using many strains.

A description is presented here of the taxonomic transition of the bacteria and some examples of the development of this identification method.

L-乾燥保存法（L-乾燥法）は微生物の長期保存のために一般に用いられる方法の1つである．我々はこのL-乾燥法を高度嫌気性古細菌であるメタン菌に適用するため，作業工程を嫌気環境に維持したL-乾燥法を開発した．供試した Methanobrevibacter arboriphilus NBRC 101200，Methanoculleus chikugoensis NBRC 101202^T，Methanothermobacter thermautotrophicus NBRC 100330^Tの3株は本L-乾燥法により良好に保存され，乾燥標品を2週間37℃に保管した加速保存試験後も良好に復元した．これらの生残菌数は，継代培養時は10⁵～10⁶ cells/ml であったのに対し，L-乾燥保存後は10⁴～10⁶ cells/ml であった．一方，酢酸を資化する Methanosarcina mazei NBRC 101201は，対数増殖期の細胞をL-乾燥保存に供した時は良好に保存され，10⁴ cells/ml が復元したが，定常期に達した細胞を供した時，著しく生残菌数が減少し，10 cells/ml 程度しか復元しなかった．このことより，メタン菌の保存には培養条件に注意を払わなければならないことが示唆された．本改変L-乾燥法はメタン菌のほか，高度嫌気性菌の長期保存や分譲の迅速化を可能にし，カルチャーコレクションの事業に貢献することが期待される．