ATCC's repository is the largest and most diverse collection of microorganisms, cell lines, and molecular genomic materials in the world. From this page you can search our online catalog to find the strains you need. From the list below you can select one or more specific collections or select the Search All. Note: Our search engine defaults to the and command when two words are entered without a symbol between them. Results of these searches will contain both words. To retrieve records with either of two words, you must use the or symbol ( | or shift-backslash).