9315421 Berlyn This award provides continued support for the operation of the Escherichia coli Genetic Stock Center located at Yale University. The Stock Center maintains a collection of around 7,000 genetically defined stock cultures of E. coli strain K-12. The Stock Center distributes these strains to the world-wide community of scientists. Requests come from investigators and teachers in the fields of microbial genetics, molecular biology, biochemistry, biophysics, medical research, biotechnology and related fields who are working in academic and governmental laboratories, non-profit research institutes, industrial laboratories and biotechnology firms. In addition to the cultures themselves, the Stock Center provides information on the histories, derivations, and genotypes of mutant derivatives of E. coli K-12 and on the identification and genetic mapping of genes on the chromosome of E. coli. The Stock Center also serves as a point of coordination for the assignment of gene symbols, allele numbers and strain designations. During the last granting period, many of the information functions have been computerized and much of the information is now available on-line to the public. During the next five years, the Stock Center will continue its service to the scientific community and will make its operation more efficient by expanding the electronic databases so that investigators can not only access the information but also use it to advance their research at their own terminals. In addition, the retiring Director, Dr. Barbara Bachmann will publish one final genetic map of E. coli during the next award period.