Biomaterial Database

Genetic inversion in the formation of an Hfr strain from a temperature-sensitive F' gal strain. 1977

P L Bergquist, and A F Jamieson

An Hfr strain (PB15) that carries a duplicated copy of the galactose operon genes flanking the integrated sex factor is unusually stable since it does not show excision of the repeated deoxyribonucleic acid segment. The right-hand galactose operon is in the normal orientation. Deletion mutations that eliminate the right-hand galactose genes, the sex factor, and some of the left-hand operon have been isolated. Mutants believed to have their left-hand galactose operon inverted were able to be induced for galactose epimerase synthesis by D-fucose but did not show escape synthesis on induction of bacteriophage lambda. Ribonucleic acid specific for the galactose operon was isolated after induction of lysogenic strains presumed to carry the galactose operon in the normal and inverted orientation. Hybridization to the isolated left and right strands of lambdapgal showed that the noninformational strand of the left-hand galactose operon of the deletion mutant of PB15 was transcribed on escape induction. These results show that inversion has occurred.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
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
D002874	Chromosome Mapping	Any method used for determining the location of and relative distances between genes on a chromosome.	Gene Mapping,Linkage Mapping,Genome Mapping,Chromosome Mappings,Gene Mappings,Genome Mappings,Linkage Mappings,Mapping, Chromosome,Mapping, Gene,Mapping, Genome,Mapping, Linkage,Mappings, Chromosome,Mappings, Gene,Mappings, Genome,Mappings, Linkage
D002876	Chromosomes, Bacterial	Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.	Bacterial Chromosome,Bacterial Chromosomes,Chromosome, Bacterial
D003090	Coliphages	Viruses whose host is Escherichia coli.	Escherichia coli Phages,Coliphage,Escherichia coli Phage,Phage, Escherichia coli,Phages, Escherichia coli
D003227	Conjugation, Genetic	A parasexual process in BACTERIA; ALGAE; FUNGI; and ciliate EUKARYOTA for achieving exchange of chromosome material during fusion of two cells. In bacteria, this is a uni-directional transfer of genetic material; in protozoa it is a bi-directional exchange. In algae and fungi, it is a form of sexual reproduction, with the union of male and female gametes.	Bacterial Conjugation,Conjugation, Bacterial,Genetic Conjugation
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
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
D005144	F Factor	A plasmid whose presence in the cell, either extrachromosomal or integrated into the BACTERIAL CHROMOSOME, determines the "sex" of the bacterium, host chromosome mobilization, transfer via conjugation (CONJUGATION, GENETIC) of genetic material, and the formation of SEX PILI.	Resistance Transfer Factor,Sex Factor F,Sex Factor, Bacterial,Bacterial Sex Factor,Bacterial Sex Factors,F Plasmid,F Plasmids,Factor, Bacterial Sex,Factors, Bacterial Sex,Fertility Factor, Bacterial,Sex Factors, Bacterial,Bacterial Fertility Factor,Bacterial Fertility Factors,F Factors,Factor F, Sex,Factor Fs, Sex,Factor, Bacterial Fertility,Factor, F,Factor, Resistance Transfer,Factors, Bacterial Fertility,Factors, F,Factors, Resistance Transfer,Fertility Factors, Bacterial,Fs, Sex Factor,Plasmid, F,Plasmids, F,Resistance Transfer Factors,Sex Factor Fs,Transfer Factor, Resistance,Transfer Factors, Resistance
D005690	Galactose	An aldohexose that occurs naturally in the D-form in lactose, cerebrosides, gangliosides, and mucoproteins. Deficiency of galactosyl-1-phosphate uridyltransferase (GALACTOSE-1-PHOSPHATE URIDYL-TRANSFERASE DEFICIENCY DISEASE) causes an error in galactose metabolism called GALACTOSEMIA, resulting in elevations of galactose in the blood.	D-Galactose,Galactopyranose,Galactopyranoside,D Galactose