title: Molecular cloning, characterization, and chromosomal localization of dapF, the Escherichia coli gene for diaminopimelate epimerase.
abstract: The Escherichia coli dapF gene was isolated from a cosmid library as a result of screening for clones overproducing diaminopimelate epimerase. Insertional mutagenesis was performed on the cloned dapF gene with a mini-Mu transposon, leading to chloramphenicol resistance. One of these insertions was transferred onto the chromosome by a double-recombination event, allowing us to obtain a dapF mutant. This mutant accumulated large amounts of LL-diaminopimelate, confirming the blockage in the step catalyzed by the dapF product, but did not require meso-diaminopimelate for growth. The dapF gene was localized in the 85-min region of the E. coli chromosome between cya and uvrD.
mesh_terms: D000591:Amino Acid Isomerases; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D003960:Diaminopimelic Acid / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D007535:Isomerases / Q000235:genetics*; D009154:Mutation; D019998:Racemases and Epimerases / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements; D003960:Diaminopimelic Acid; D007535:Isomerases; D019998:Racemases and Epimerases; D000591:Amino Acid Isomerases; C042032:diaminopimelate epimerase