Biomaterial Database

The hisT-purF region of the Escherichia coli K-12 chromosome. Identification of additional genes of the hisT and purF operons. 1987

M L Nonet, and C C Marvel, and D R Tolan

A 9.7-kilobase pair segment of the Escherichia coli chromosome spanning the hisT and purF loci has been characterized. Six genes were identified in this region by complete DNA sequence analysis, in vivo expression in maxicells, and RNA transcript analysis. S1 nuclease analysis has demonstrated that some of these genes are part of the hisT or purF operons. Two of the newly identified genes, dedA and dedB, were localized immediately downstream of hisT in the hisT operon. Two other genes, denoted dedC and dedD, have been localized between the hisT and purF operons. The other two genes, dedE and dedF flank the purF gene. dedE has been previously described as the first gene in the purF operon (Makaroff, C.A., and Zalkin, H. (1985) J. Biol. Chem. 260, 10378-10387). dedF was localized downstream from purF and is part of the purF operon. In addition, dedF is homologous to the ubiX gene of Salmonella typhimurium. Adjacent to dedF is the E. coli homologue of the S. typhimurium argT locus encoding the lysine/arginine/ornithine-binding protein. All of the genes in this region of the chromosome were found to be transcribed in a counter-clockwise direction on the E. coli map which revises the direction of purF transcription.

UI	MeSH Term	Description	Entries
D009876	Operon	In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.	Operons
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D002875	Chromosomes	In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Chromosome
D003062	Codon	A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).	Codon, Sense,Sense Codon,Codons,Codons, Sense,Sense Codons
D004262	DNA Restriction Enzymes	Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.	Restriction Endonucleases,DNA Restriction Enzyme,Restriction Endonuclease,Endonuclease, Restriction,Endonucleases, Restriction,Enzymes, DNA Restriction,Restriction Enzyme, DNA,Restriction Enzymes, DNA
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D001330	Electronic Data Processing	Applications that store and process large quantities of data.	Automatic Data Processing,Bar Codes,Computer Data Processing,Data Processing, Automatic,Information Processing, Automatic,Optical Readers,Information Processing,Automatic Information Processing,Bar Code,Codes, Bar,Data Processing, Computer,Data Processing, Electronic,Optical Reader,Processing, Automatic Data,Processing, Automatic Information,Processing, Computer Data,Processing, Electronic Data,Processing, Information
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA