Properties of adenyl cyclase and cyclic adenosine 3',5'-monophosphate receptor protein-deficient mutants of Escherichia coli.
Reads0
Chats0
TLDR
Several spontaneous cya and crp mutants of Escherichia coli have been selected as clones simultaneously resistant to phage lambda and nalidixic acid and characterized and found to be multiply carbohydrate negative and nonmotile in conformity with similar previously isolated mutants.Abstract:Â
Several spontaneous cya and crp mutants of Escherichia coli have been selected as clones simultaneously resistant to phage lambda and nalidixic acid and characterized. Both cya and crp mutants have been found to grow as cocci with increased doubling times. They have increased resistance to some mutagens (methylmethanesulfonate, ultraviolet light, gamma rays), antibiotics (nalidixic acid, ampicillin), phages (lambda, T6), sublethal heat and hypotonic shock, and decreased resistance to neutral detergents (sodium dodecyl sulfate, sodium deoxycholate), a protein synthesis inhibitor (streptomycin), and a respiratory inhibitor (sodium azide). The nature of changes in cell parameters indicate fundamental alterations in the envelope structure of the cya and crp mutant cells. The new cya and crp mutants have been found to be multiply carbohydrate negative and nonmotile in conformity with similar previously isolated mutants. Studies of revertants and phi 80 cya$sup +$ and phi 80 cya transductants indicated that the pleiotropic phenotype is related to a single mutational event at the cya or the crp locus in the mutants. (auth)read more
Citations
More filters
Journal ArticleDOI
Cyclic AMP in prokaryotes.
J. L. Botsford,J G Harman +1 more
TL;DR: This review summarizes recent work focused on elucidating the molecular mechanisms of CRP-cAMP complex-mediated processes in enteric coliforms and suggests a role for cAMP has been suggested in nitrogen fixation.
Book
Regulation of Gene Expression in Escherichia Coli
E. C. C. Lin,A. Simon Lynch +1 more
TL;DR: This chapter discusses the role of Translational Control in Growth Rate Regulation in Bacterial Transport Systems and Global Regulatory Networks, as well as models based on recent models for RNA Chain Elongation.
Journal ArticleDOI
Survival of enteric bacteria in seawater
Yael Rozen,Shimshon Belkin +1 more
TL;DR: Using Escherichia coli as a model, a surprisingly small number of genes was found that, when mutated, significantly affect seawater sensitivity of this bacterium.
Journal ArticleDOI
Mutant isolation and molecular cloning of mre genes, which determine cell shape, sensitivity to mecillinam, and amount of penicillin-binding proteins in Escherichia coli.
TL;DR: A chromosomal region of Escherichia coli contiguous to the fabE gene at 71 min on the chromosomal map contains multiple genes that are responsible for determination of the rod shape and sensitivity to the amidinopenicillin mecillinam.
Journal ArticleDOI
Genetic and biochemical characterization of norfloxacin resistance in Escherichia coli.
TL;DR: In Escherichia coli the frequency of spontaneous single-step mutation to high levels of resistance to the newer 4-quinolone agent norfloxacin was confirmed to be over 300-fold lower than that to the older agent nalidixic acid.
References
More filters
Journal ArticleDOI
Mutants of escherichia coli requiring methionine or vitamin b12
TL;DR: Certain biochemical properties of auxotrophicl mutants of Escherichia coli with specific growth requirements for most of the known water-soluble vitamins, as well as of others responding to methionine but not to B,2 are described.
Journal ArticleDOI
The barrier function of the gram-negative envelope
TL;DR: The evidence that the outer membrane provides a permeability barrier that makes gramnegative bacteria less permeable than gram-positive bacteria to a large variety of molecules, which includes many drugs and antimetabolites is summarized.
Journal ArticleDOI
Observations on the Mechanism of Action of Penicillin.
TL;DR: Penicillin acts either as a bacteriostatic or bactericidal agent depending on the experimental conditions and appears to be effective only when active multiplication takes place.
Journal ArticleDOI
Mechanism of Action of Nalidixic Acid on Escherichia coli II. Inhibition of Deoxyribonucleic Acid Synthesis
TL;DR: It is shown that the capacity of E. coli 15TAU to synthesize DNA in a medium containing thymine, arginine, and uracil may be restored by a simple filtration and washing process, indicating that the drug is not firmly bound.
Journal ArticleDOI
Effect of Ethylenediaminetetraacetic Acid, Triton X-100, and Lysozyme on the Morphology and Chemical Composition of Isolated Cell Walls of Escherichia coli
TL;DR: The results are interpreted in terms of the types of noncovalent bonds involved in maintaining the organized structure of the cell wall and suggest that the main forces involved are hydrophobic protein-protein interactions between thecell wall proteins and to a lesser degree a stabilization of protein- protein and protein-lipopolysaccharide interactions by divalent cations.