Biomaterial Database

Repression of the histidine operon: effect of the first enzyme on the kinetics of repression. 1969

J S Kovach, and M A Berberich, and P Venetianer, and R F Goldberger

Kinetic studies on repression of the enzymes for histidine biosynthesis in Salmonella typhimurium showed that, upon addition of histidine to a derepressed culture, the enzymes became repressed in a temporal sequence which corresponds with the positional sequence of the genes in the histidine operon. This serial pattern of repression occurred under conditions in which the feedback site of the first enzyme for histidine biosynthesis is intact. When this site was rendered nonfunctional the pattern of repression was changed so that all of the enzymes became repressed concomitantly. These results suggest that the first enzyme for histidine biosynthesis plays a hitherto unrecognized role in control of the histidine system.

UI	MeSH Term	Description	Entries
D008967	Molecular Biology	A discipline concerned with studying biological phenomena in terms of the chemical and physical interactions of molecules.	Biochemical Genetics,Biology, Molecular,Genetics, Biochemical,Genetics, Molecular,Molecular Genetics,Biochemical Genetic,Genetic, Biochemical,Genetic, Molecular,Molecular Genetic
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
D004794	Enzyme Repression	The interference in synthesis of an enzyme due to the elevated level of an effector substance, usually a metabolite, whose presence would cause depression of the gene responsible for enzyme synthesis.	Repression, Enzyme
D004798	Enzymes	Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.	Biocatalyst,Enzyme,Biocatalysts
D005246	Feedback	A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.	Feedbacks
D005827	Genetics, Microbial	A subdiscipline of genetics which deals with the genetic mechanisms and processes of microorganisms.	Microbial Genetics,Genetic, Microbial,Microbial Genetic
D006639	Histidine	An essential amino acid that is required for the production of HISTAMINE.	Histidine, L-isomer,L-Histidine,Histidine, L isomer,L-isomer Histidine
D012486	Salmonella typhimurium	A serotype of Salmonella enterica that is a frequent agent of Salmonella gastroenteritis in humans. It also causes PARATYPHOID FEVER.	Salmonella typhimurium LT2