Use of Neomycin in the Isolation of Mutants Blocked in Energy Conservation in Escherichia coli

Abstract

A neomycin-resistant mutant of Escherichia coli K-12 unable to grow on Krebs cycle intermediates has been isolated. The mutant retained its respiratory capacity, but lacked membrane Mg 2+ -Ca 2+ -stimulated adenosine triphosphatase activity (EC 3.6.1.3).

Active transport in mutants of Escherichia coli with alterations in the membrane ATPase complex

“…The strains used in this report are all Lac +-transductants [11], of the parent A428 [1] and the mutants NI44 [1] and BV4 [2].…”

“…A number of mutants ofEscherichia coli have been isolated with a defect in oxidative phosphorylation [1][2][3][4][5][6][7]. The mutants isolated thus far, all map in the same region of the chromosome (73.5 min) and all are affected in the membrane Mg 2÷-Ca 2+ ATPase complex.…”

“…The mutants isolated thus far, all map in the same region of the chromosome (73.5 min) and all are affected in the membrane Mg 2÷-Ca 2+ ATPase complex. One class of mutants has been shown to lack ATPase catalytic activity [1,3,5,7], while a second class of mutants retains the ATPase activity [2,4,6], but in a form which is resistant to the energy transfer inhibitor DCCD** [2]. Studies of active transport in mutants of the first class have provided evidence that phosphate-bond energy is not required for the aerobic transport of certain solutes in E. coli [5,8,9].…”

Acid sensitivity of neomycin-resistant mutants of Oenococcus oeni: a relationship between reduction of ATPase activity and lack of malolactic activity

“…Previous studies showed that there is a relationship between resistance to neomycin and a defect in F 0 F 1 ATPase [18,19]. As the growth of the wildtype strain Lo84.13 was found to be dramatically reduced with 150 Wg ml 31 of neomycin sulfate, two sets of 10 10 colony forming units (CFU) were treated with a lethal concentration of 300 Wg ml 31 of neomycin.…”

On proton-coupled information transfer along the surface of biological membranes and the mode of action of certain colicins

“…Fourthly, the manner in which such a variety of energy-uncoupled mutants may be isolated (e.g. [41,88,[99][100][101]) by selection for resistance to both charged and uncharged aminoglycoside antibiotics, suggests that the conformational state of at least part of the protoneural network modulates the rate at which such antibiotics are taken up by bacterial cells. Fifthly, it allows a ready harmonisation of the widely accepted general theory of protonic coupling with the perhaps controversial view [102] that the bulk-phase mitochondrial membrane potential during ATP synthesis is in fact energetically insignificant.…”