title: dfp Gene of Escherichia coli K-12, a locus affecting DNA synthesis, codes for a flavoprotein.
abstract: The cloned dfp gene complements dna-707 (now designated dfp-707), a temperature-sensitive conditionally lethal mutation that results in a slow cessation of DNA synthesis while protein synthesis is maintained. In vitro and in vivo experiments failed to demonstrate a specific defect in the initiation of DNA replication, and turn-off of DNA synthesis at high temperature was slower than that of a typical initiation (dnaA) mutant. The gene was localized, and its product was identified through the construction and analysis of deletion and insertion mutants of dfp-containing plasmids. dfp is located between the rpmB and dut genes at 81 min on the linkage map of Escherichia coli K-12. It is transcribed clockwise, independently of dut. The ability of a plasmid to complement a chromosomal dfp-707 mutation was correlated with its ability to produce a 45-kilodalton polypeptide. The purified protein contained 1 mol of flavin mononucleotide per mol of polypeptide.
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics*; D005420:Flavoproteins / Q000032:analysis; D005816:Genetic Complementation Test; D008970:Molecular Weight; D009154:Mutation; D010957:Plasmids; D014176:Protein Biosynthesis; D012965:Sodium Chloride / Q000378:metabolism; D012995:Solubility; D013696:Temperature; D013941:Thymine / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D005420:Flavoproteins; D012965:Sodium Chloride; D013941:Thymine