๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

A new conditional lethal mutator (dnaQ49) in Escherichia coli K12

โœ Scribed by Horiuchi, Takashi ;Maki, Hisaji ;Sekiguchi, Mutsuo


Publisher
Springer
Year
1978
Tongue
English
Weight
652 KB
Volume
163
Category
Article
ISSN
0026-8925

No coin nor oath required. For personal study only.

โœฆ Synopsis


A conditional lethal mutator, dnaQ49, was found in Escherichia coli K12. The dnaQ49 mutation caused stimulation of rifampicin-, nalidixic acid- and streptomycin-resistant mutation frequencies 100 to 2000 fold at 30 degrees C and the frequencies were further increased 50 to 100 fold at 35 degrees C or higher temperatures. Cells carrying dnaQ49 were unable to grow in salt-free L-broth at 44.5 degrees C, and DNA synthesis but not protein synthesis of the cells was suppressed under the restrictive conditions. The dnaQ gene was located at about 5 min on the E. coli linkage map and the order of the genes residing in this region was determined to be ton A-dnaE-metD-dnaQ-pro A.


๐Ÿ“œ SIMILAR VOLUMES


Isolation and characterisation of a stra
โœ Orr, Elisha ;Fairweather, Neil F. ;Barry Holland, I. ;Pritchard, Robert H. ๐Ÿ“‚ Article ๐Ÿ“… 1979 ๐Ÿ› Springer ๐ŸŒ English โš– 877 KB

A strain which carries a mutation conferring clorobiocin resistance and temperature sensitivity for growth was isolated from Escherichia coli K12. Genetic mapping and the molecular weight of the gene product suggest that the mutation is in the cou gene, specifying a sub-unit of DNA gyrase. Nuclear o

Lethal mutations in the structural gene
โœ Freudl, Roland ;Braun, Gabi ;Hindennach, Ingrid ;Henning, Ulf ๐Ÿ“‚ Article ๐Ÿ“… 1985 ๐Ÿ› Springer ๐ŸŒ English โš– 786 KB

The gene ompA encodes a major outer membrane protein of Escherichia coli. Localized mutagenesis of the part of the gene corresponding to the 21-residue signal sequence and the first 45 residues of the protein resulted in alterations which caused cell lysis when expressed. DNA sequence analyses revea

New regulatory mutations affecting the e
โœ Saint-Girons, Isabelle ๐Ÿ“‚ Article ๐Ÿ“… 1978 ๐Ÿ› Springer ๐ŸŒ English โš– 517 KB

The promoter of the threonine operon was joined to the structural genes of the lac operon in Escherichia coli K 12. The synthesis of beta-galactosidase was thus repressed by threonine plus isoleucine in the fusion strains. To isolate mutations which affect the expression of the threonine operon, alt

Genetic mapping of a putative temperatur
โœ Abdul Jabbar, M. ;Jayaraman, R. ๐Ÿ“‚ Article ๐Ÿ“… 1978 ๐Ÿ› Springer ๐ŸŒ English โš– 531 KB

A putative temperature-sensitive transcription mutant described earlier (Jabbar and Jayaraman, 1976) has been genetically mapped. The locus maps at 38 min to the left of aroD. The mutation is recessive to the wild type and it affects a gene probably other than the genes coding for the alpha and beta