On the nature of permeability of sarcoma-180 cells to amethopterin in vitro.

@article{Hakala1965OnTN,
  title={On the nature of permeability of sarcoma-180 cells to amethopterin in vitro.},
  author={Maire T. Hakala},
  journal={Biochimica et biophysica acta},
  year={1965},
  volume={102 1},
  pages={
          210-25
        }
}
  • M. Hakala
  • Published 25 May 1965
  • Biology
  • Biochimica et biophysica acta

On the nature of a transport alteration determining resistance to amethopterin in the L1210 leukemia.

Kinetic analysis revealed an increase in the Michaelis constant for the system in these resistant cells, suggesting an alteration in the binding properties of a carrier component as the basis for the impairment.

Differential cell permeability and the basis for selective activity of methotrexate during therapy of the L1210 leukemia.

A far greater persistence of free MTX and a more sustained metabolic effect in L1210 cells than in small intestine is revealed, at least in part, to a more effective influx of drug in L 1210 cells at low plasma levels.

Stereochemical characteristics of the folate-antifolate transport mechanism in L1210 Leukemia cells.

The relationship between the values for initial velocity of influx (v), the Km and Vmax obtained with each analog are in agreement with that predicted by the Michaelis-Menten equation and is consistent with the notion that differences in rates of influx are attributable to differences in the affinity of the carrier for the system.

Genetically Alterable Transport of Amethopterin in Diplococcus pneumoniae I. Physiological Properties and Kinetics of the Wild-type System

A system of H3-amethopterin uptake, physiologically and kinetically resembling active transport, has been described in Diplococcus pneumoniae. Uptake by this system has a pH optimum near 6.0, is

Effects of 2,4-dinitrophenol and other metabolic inhibitors on the bidirectional carrier fluxes, net transport, and intracellular binding of methotrexate in Ehrlich ascites tumor cells.

Although most metabolic inhibitors affect MTX transport by inhibition of energy metabolism, DNP affects the system in at least two ways: (a) by energy depletion similar to that of other metabolic inhibitors; and (£>) by an apparent interaction with the carrier at the cell membrane which inhibits bidirectional fluxes.
...

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UPTAKE OF AMINOPTERIN BY BACILLUS SUBTILIS

The 2-methyl-4-amino-5-hydroxymethylpyrimidine form of the thiamine pyrimidine has been examined for its effect on the entry of aminopterin-2-C04 into B. subtilis.

Chromosomal constitution and amethopterin resistance in cultured mouse cells.

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