Mechanisms of inhibition by ascorbate of microbial mutagenesis induced by N-nitroso compounds

Research output: Contribution to journalArticle

Abstract

Mutagenesis induced by N-methyl-N-nitrosoguanidine (MNNG) and dimethylnitrosamine (DMN) in Salmonella TA 1530 was inhibited by ascorbate. Inhibition of MNNG-induced mutagenesis resulted from a reaction between ascorbate and MNNG that led to consumption of MNNG. The rate of this reaction was considerably enhanced by catalytic amounts of Cu(II) and Fe(III). No direct reaction between DMN and ascorbate was detectable, but relatively high concentrations of Cu(II) enhanced inhibition of DMN-induced mutagenesis by ascorbate. Added protein reduced the effectiveness of Cu(II) as a catalyst of the reaction between ascorbate and MNNG, which suggested that the microsomal protein necessary to activate DMN, may reduce the concentration of free Cu(II) and thereby lower its catalytic efficiency. Mutagenesis by N-methyl-N-nitrosourea was not inhibited by ascorbate.

Original languageEnglish (US)
Pages (from-to)2018-2022
Number of pages5
JournalCancer Research
Volume38
Issue number7
StatePublished - 1978

Fingerprint

Nitroso Compounds
Nitrosoguanidines
Dimethylnitrosamine
Mutagenesis
Methylnitrosourea
Salmonella
Proteins

ASJC Scopus subject areas

  • Cancer Research
  • Oncology

Cite this

Mechanisms of inhibition by ascorbate of microbial mutagenesis induced by N-nitroso compounds. / Guttenplan, Joseph.

In: Cancer Research, Vol. 38, No. 7, 1978, p. 2018-2022.

Research output: Contribution to journalArticle

@article{445c011255a24ef1afe471a04aa9823d,
title = "Mechanisms of inhibition by ascorbate of microbial mutagenesis induced by N-nitroso compounds",
abstract = "Mutagenesis induced by N-methyl-N-nitrosoguanidine (MNNG) and dimethylnitrosamine (DMN) in Salmonella TA 1530 was inhibited by ascorbate. Inhibition of MNNG-induced mutagenesis resulted from a reaction between ascorbate and MNNG that led to consumption of MNNG. The rate of this reaction was considerably enhanced by catalytic amounts of Cu(II) and Fe(III). No direct reaction between DMN and ascorbate was detectable, but relatively high concentrations of Cu(II) enhanced inhibition of DMN-induced mutagenesis by ascorbate. Added protein reduced the effectiveness of Cu(II) as a catalyst of the reaction between ascorbate and MNNG, which suggested that the microsomal protein necessary to activate DMN, may reduce the concentration of free Cu(II) and thereby lower its catalytic efficiency. Mutagenesis by N-methyl-N-nitrosourea was not inhibited by ascorbate.",
author = "Joseph Guttenplan",
year = "1978",
language = "English (US)",
volume = "38",
pages = "2018--2022",
journal = "Journal of Cancer Research",
issn = "0008-5472",
publisher = "American Association for Cancer Research Inc.",
number = "7",

}

TY - JOUR

T1 - Mechanisms of inhibition by ascorbate of microbial mutagenesis induced by N-nitroso compounds

AU - Guttenplan, Joseph

PY - 1978

Y1 - 1978

N2 - Mutagenesis induced by N-methyl-N-nitrosoguanidine (MNNG) and dimethylnitrosamine (DMN) in Salmonella TA 1530 was inhibited by ascorbate. Inhibition of MNNG-induced mutagenesis resulted from a reaction between ascorbate and MNNG that led to consumption of MNNG. The rate of this reaction was considerably enhanced by catalytic amounts of Cu(II) and Fe(III). No direct reaction between DMN and ascorbate was detectable, but relatively high concentrations of Cu(II) enhanced inhibition of DMN-induced mutagenesis by ascorbate. Added protein reduced the effectiveness of Cu(II) as a catalyst of the reaction between ascorbate and MNNG, which suggested that the microsomal protein necessary to activate DMN, may reduce the concentration of free Cu(II) and thereby lower its catalytic efficiency. Mutagenesis by N-methyl-N-nitrosourea was not inhibited by ascorbate.

AB - Mutagenesis induced by N-methyl-N-nitrosoguanidine (MNNG) and dimethylnitrosamine (DMN) in Salmonella TA 1530 was inhibited by ascorbate. Inhibition of MNNG-induced mutagenesis resulted from a reaction between ascorbate and MNNG that led to consumption of MNNG. The rate of this reaction was considerably enhanced by catalytic amounts of Cu(II) and Fe(III). No direct reaction between DMN and ascorbate was detectable, but relatively high concentrations of Cu(II) enhanced inhibition of DMN-induced mutagenesis by ascorbate. Added protein reduced the effectiveness of Cu(II) as a catalyst of the reaction between ascorbate and MNNG, which suggested that the microsomal protein necessary to activate DMN, may reduce the concentration of free Cu(II) and thereby lower its catalytic efficiency. Mutagenesis by N-methyl-N-nitrosourea was not inhibited by ascorbate.

UR - http://www.scopus.com/inward/record.url?scp=0018098757&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018098757&partnerID=8YFLogxK

M3 - Article

VL - 38

SP - 2018

EP - 2022

JO - Journal of Cancer Research

JF - Journal of Cancer Research

SN - 0008-5472

IS - 7

ER -