Bruce N. Ames

Altered Sulfur Amino Acid Metabolism In Immune Cells of Children Diagnosed With Autism (2008)

Jung H. Suh, William J. Walsh, Woody R. McGinnis, Allen Lewis, Bruce N. Ames

Autism Spectrum Disorder (ASD) is a behaviorally defined neurodevelopmental disorder whose etiology is poorly understood. Recent studies have shown that autistic children may be experiencing...

Zinc Deficiency and Microtubule Function in Prostate Cells (2006)

Ames, Bruce N.

Zinc deficiency is surprisingly common in the US. One organ expected to suffer during zinc deficiency is the prostate, since it is the greatest tissue accumulator of zinc in men. Zinc uptake in...

Quantitative and Qualitative Extrapolation of Carcinogenesis Between Species, (2005)

Gold, Lois S., Manley, Neela B., Ames, Bruce N.

As currently conducted, standard rodent bioassays do not provide sufficient information to assess carcinogenic risk to humans at doses thousands of times below the maximum tolerated dose. Recent...

Methylenetetrahydrofolate reductase C677T polymorphism does not alter folic acid deficiency-induced uracil incorporation into primary human lymphocyte DNA in vitro (2001)

Crott, Jimmy W., Mashiyama, Susan T., Ames, Bruce N., Fenech, Michael F.

Methylenetetrahydrofolate reductase (MTHFR) is an enzyme which converts 5,10-methylene tetrahydrofolate (5,10-MnTHF) to 5-methyl tetrahydrofolate. A common C to T transition (C677T) in the MTHFR gene...

Immunoaffinity isolation of urinary 8-hydroxy-2'-deoxygunosine and 8-hydroxyguanine and quantitation of 8-hydroxy-2'deoxyguanosine in DNA by polyclonal antibodies (1991)

Degan, Paolo, Shigenaga, Mark K., Park, Eun-Mi, Alperin, Peter E., Ames, Bruce N.

An immunoaffinity column is described that facilitates the analysis of oxidative DNA adducts excised from DNA are excreted in urine and can assayed as a measure of DNA damage in individuals....

Some Tautologous Aspects of the Comparison of Carcinogenic Potency in Rats and Mice (1985)

BERNSTEIN, LESLIE, GOLD, LOIS S., AMES, BRUCE N., PIKE, MALCOLM C., HOEL, DAVID G.

Some Tautologous Aspects of the Comparison of Carcinogenic Potency in Rats and Mice. BERNSTEIN, L., GOLD, L. S., AMES, B. N., PIKE, M. C, and HOEL, D. G. (1985). Fundam. Appl. Toxicol. 5, 79–86. In...

c/s 2-Methylthio-ribosylzeatin (ms2io6 is present in the transfer RNA of Salmonella ryphimurium, but not Escherichis coti (1982)

Buck, Martin, McCloskey, James A., Basile, Brenda, Ames, Bruce N.

He have identified the cis isomer of N6-(4-hydroxy-isopentenyl)-2-methylthioadenosine (ms2 io6 A) aa a component of the tRNA of Salmonella typhimurlum. This is the first report of this compound in...

The b iosynthesis of histidine: imidazoleglycerol phosphate, imidazoleacteol phosphate, and histidinol phosphate (1955)

Ames, Bruce N., Mitchell, Herschel K.

This is a report on the isolation and characterization of D-erythro-imidazoleglycerol phosphate (IGP), imidazoleacetol phosphate (IAP), and L-histidinol phosphate, which are accumulated in the...

The biosynthesis of histidine: imidazoleglycerol phosphate, imidazoleacetol phosphate, and histidinol phosphate (1955)

Ames, Bruce N., Mitchell, Herschel K.

This is a report on the isolation and characterization of D-erythro-imidazoleglycerol phosphate (IGP), imidazoleacetol phosphate (IAP), and L-histidinol phosphate, which are accumulated in the...

A method for detecting abasic sites in living cells: Age-dependent changes in base excision repair

Atamna, Hani, Cheung, Ivana, Ames, Bruce N.

Apurinic/apyrimidinic (AP) sites are common DNA lesions that arise from spontaneous depurination or by base excision repair (BER) of modified bases. A biotin-containing aldehyde-reactive probe (ARP)...

γ-Tocopherol and its major metabolite, in contrast to α-tocopherol, inhibit cyclooxygenase activity in macrophages and epithelial cells

Jiang, Qing, Elson-Schwab, Ilan, Courtemanche, Chantal, Ames, Bruce N.

Cyclooxygenase-2 (COX-2)-catalyzed synthesis of prostaglandin E2 (PGE2) plays a key role in inflammation and its associated diseases, such as cancer and vascular heart disease. Here we report that...

DNA oxidation matters: The HPLC–electrochemical detection assay of 8-oxo-deoxyguanosine and 8-oxo-guanine

Helbock, Harold J., Beckman, Kenneth B., Shigenaga, Mark K., Walter, Patrick B., Woodall, Alan A., Yeo, Helen C., ...

Oxidative DNA damage is important in aging and the degenerative diseases of aging such as cancer. Estimates commonly rely on measurements of 8-oxo-2′-deoxyguanosine (oxo8dG), an adduct that occurs...

Mitochondrial decay in hepatocytes from old rats: Membrane potential declines, heterogeneity and oxidants increase

Hagen, Tory M., Yowe, David L., Bartholomew, James C., Wehr, Carol M., Do, Katherine L., Park, Jin-Y., ...

Mitochondrial function during aging was assessed in isolated rat hepatocytes to avoid the problem of differential lysis when old, fragile mitochondria are isolated. Rhodamine 123, a fluorescent dye...

Inflammation and NOx-induced nitration: Assay for 3-nitrotyrosine by HPLC with electrochemical detection

Shigenaga, Mark K., Lee, Ho H., Blount, Benjamin C., Christen, Stephan, Shigeno, Eric T., Yip, Helena, ...

The identification of 15N-labeled 3-nitrotyrosine (NTyr) by gas chromatography/mass spectroscopy in protein hydrolyzates from activated RAW 264.7 macrophages incubated with 15N-l-arginine confirms...

γ-Tocopherol traps mutagenic electrophiles such as NOx and complements α-tocopherol: Physiological implications

Christen, Stephan, Woodall, Alan A., Shigenaga, Mark K., Southwell-Keely, Peter T., Duncan, Mark W., Ames, Bruce N.

Peroxynitrite, a powerful mutagenic oxidant and nitrating species, is formed by the near diffusion-limited reaction of ·NO and O2⨪ during activation of phagocytes. Chronic inflammation induced by...

Folate deficiency causes uracil misincorporation into human DNA and chromosome breakage: Implications for cancer and neuronal damage

Blount, Benjamin C., Mack, Matthew M., Wehr, Carol M., MacGregor, James T., Hiatt, Robert A., Wang, Gene, ...

Folate deficiency causes massive incorporation of uracil into human DNA (4 million per cell) and chromosome breaks. The likely mechanism is the deficient methylation of dUMP to dTMP and subsequent...

Acetyl-l-carnitine fed to old rats partially restores mitochondrial function and ambulatory activity

Hagen, Tory M., Ingersoll, Russell T., Wehr, Carol M., Lykkesfeldt, Jens, Vinarsky, Vladimir, Bartholomew, James C., ...

Mitochondrial function and ambulatory activity were monitored after feeding old rats acetyl-l-carnitine (ALCAR). Young (3–5 mo) and old (22–28 mo) rats were given a 1.5% (wt/vol) solution of...

Feeding acetyl-l-carnitine and lipoic acid to old rats significantly improves metabolic function while decreasing oxidative stress

Hagen, Tory M., Liu, Jiankang, Lykkesfeldt, Jens, Wehr, Carol M., Ingersoll, Russell T., Vinarsky, Vladimir, ...

Mitochondrial-supported bioenergetics decline and oxidative stress increases during aging. To address whether the dietary addition of acetyl-l-carnitine [ALCAR, 1.5% (wt/vol) in the drinking water]...

Age-associated mitochondrial oxidative decay: Improvement of carnitine acetyltransferase substrate-binding affinity and activity in brain by feeding old rats acetyl-l- carnitine and/or R-α-lipoic acid

Liu, Jiankang, Killilea, David W., Ames, Bruce N.

We test whether the dysfunction with age of carnitine acetyltransferase (CAT), a key mitochondrial enzyme for fuel utilization, is due to decreased binding affinity for substrate and whether this...

Iron deficiency and iron excess damage mitochondria and mitochondrial DNA in rats

Walter, Patrick B., Knutson, Mitchell D., Paler-Martinez, Andres, Lee, Sonia, Xu, Yu, Viteri, Fernando E., ...

Approximately two billion people, mainly women and children, are iron deficient. Two studies examined the effects of iron deficiency and supplementation on rats. In study 1, mitochondrial functional...

Memory loss in old rats is associated with brain mitochondrial decay and RNA/DNA oxidation: Partial reversal by feeding acetyl-l-carnitine and/or R-α-lipoic acid

Liu, Jiankang, Head, Elizabeth, Gharib, Afshin M., Yuan, Wenjun, Ingersoll, Russell T., Hagen, Tory M., ...

Accumulation of oxidative damage to mitochondria, protein, and nucleic acid in the brain may lead to neuronal and cognitive dysfunction. The effects on cognitive function, brain mitochondrial...

Heme deficiency may be a factor in the mitochondrial and neuronal decay of aging

Atamna, Hani, Killilea, David W., Killilea, Alison Nisbet, Ames, Bruce N.

Heme, a major functional form of iron in the cell, is synthesized in the mitochondria by ferrochelatase inserting ferrous iron into protoporphyrin IX. Heme deficiency was induced with...

Histidyl-Transfer Ribonucleic Acid Synthetase Mutants Requiring a High Internal Pool of Histidine for Growth

Straus, Daniel S., Ames, Bruce N.

Mutants that require histidine due to an altered structural gene for the histidyl-transfer ribonucleic acid synthetase (hisS) have been isolated by a general selection for histidine-requiring strains...

Enriched Selection of Dominant Mutations: Histidine Operator Mutations

Chang, George W., Straus, Daniel, Ames, Bruce N.

In the course of selection of bacteria with derepressed levels of histidine biosynthetic enzymes, it was found that when mutagen-treated cells were spread on a selective medium without allowing...

Salmonella typhimurium Mutants with Alternate Requirements for Vitamin B6 or Isoleucine

Guirard, Beverly M., Ames, Bruce N., Snell, Esmond E.

Several mutants of Salmonella typhimurium LT-2, isolated as auxotrophs for vitamin B6, grew without the added vitamin when supplied with either isoleucine, α-ketobutyrate, or...

Histidine Regulation in Salmonella typhimurium VIII. Mutations of the hisT Gene

Chang, George W., Roth, John R., Ames, Bruce N.

The hisT gene, one of six genes in which mutation causes derepression of the histidine operon in Salmonella typhimurium, is shown to code for a protein that is not essential for the growth of the...

Iron Uptake in Salmonella typhimurium: Utilization of Exogenous Siderochromes as Iron Carriers

Luckey, Mary, Pollack, Jay R., Wayne, Rush, Ames, Bruce N., Neilands, J. B.

Aerobic microorganisms have evolved a variety of siderochromes, special ligands which can dissolve insoluble ferric iron and facilitate its transport into the cell. We have found that enb mutants of...

Procedure for Identifying Nonsense Mutations

Berkowitz, David, Hushon, Judith M., Whitfield, Harvey J., Roth, John, Ames, Bruce N.

A method has been devised for the rapid identification of nonsense mutations (UAG, UAA, UGA codons) in Salmonella. The mutations to be tested are reverted, and the revertants are replica-printed onto...

Iron Transport in Salmonella typhimurium: Mutants Blocked in the Biosynthesis of Enterobactin

Pollack, J. R., Ames, Bruce N., Neilands, J. B.

A number of mutants of Salmonella typhimurium were isolated which are blocked in the biosynthesis of enterobactin, an iron chelator that is secreted by the wild-type bacteria when they are grown on...

Compounds Which Serve as the Sole Source of Carbon or Nitrogen for Salmonella typhimurium LT-2

Gutnick, David, Calvo, Joseph M., Klopotowski, Tadeusz, Ames, Bruce N.

About 600 compounds were screened as possible carbon or nitrogen sources for Salmonella typhimurium LT-2. About 100 utilizable compounds were found.

A Simple Method for the Detection of Mutagens in Urine: Studies with the Carcinogen 2-Acetylaminofluorene

Durston, William E., Ames, Bruce N.

We described previously a simple test on petri plates for detecting many carcinogens as mutagens using an especially sensitive set of bacterial strains to detect mutagens and a rat, or human, liver...

Pleiotropy of hisT Mutants Blocked in Pseudouridine Synthesis in tRNA: Leucine and Isoleucine-V aline Operons

Cortese, Riccardo, Landsberg, Raymond, Vonder Haar, R. A., Umbarger, H. E., Ames, Bruce N.

The hisT gene codes for an enzyme responsible for the conversion of uridine to pseudouridine (Ψ) in the anticodon region of many tRNA species in Salmonella typhimurium. We have previously shown that...

Adenosine 3′:5′-Cyclic Monophosphate Concentration in the Bacterial Host Regulates the Viral Decision between Lysogeny and Lysis

Hong, Jen-Shiang, Smith, Gerald R., Ames, Bruce N.

Mutants of Salmonella typhimurium defective in adenylate cyclase (cya gene) or in cAMP receptor protein (crp gene) are lysogenized at reduced frequency by phage P22. One class of the bacterial...

Localized Mutagenesis of Any Specific Small Region of the Bacterial Chromosome

Hong, Jen-Shiang, Ames, Bruce N.

A method, which we call localized mutagenesis, is described for the isolation of temperature-sensitive and other types of mutations in any specific small region (about 1%) of the bacterial...

Carcinogens as Frameshift Mutagens: Metabolites and Derivatives of 2-Acetylaminofluorene and Other Aromatic Amine Carcinogens

Ames, Bruce N., Gurney, E. G., Miller, James A., Bartsch, H.

Several carcinogenic metabolites of the carcinogen 2-acetyl-aminofluorene, especially 2-nitrosofluorene and N-hydroxy-2-aminofluorene, are potent frameshift mutagens for Salmonella typhimurium....

Illicit Transport: The Oligopeptide Permease

Ames, Bruce N., Ames, Giovanna Ferro-Luzzi, Young, Janis Dillaha, Tsuchiya, Dorinne, Lecocq, Jean

The oligopeptide permease of Escherichia coli has been characterized by Payne, Gilvarg, and their colleagues. We have confirmed its existence in Salmonella typhimurium, and have isolated a series of...

An Improved Bacterial Test System for the Detection and Classification of Mutagens and Carcinogens

Ames, Bruce N., Lee, Frank D., Durston, William E.

We previously described a set of four strains of Salmonella typhimurium designed for detecting the various types of mutagens, and showed their utility in detecting a wide variety of carcinogens as...

Carcinogens are Mutagens: A Simple Test System Combining Liver Homogenates for Activation and Bacteria for Detection

Ames, Bruce N., Durston, William E., Yamasaki, Edith, Lee, Frank D.

18 Carcinogens, including aflatoxin B1, benzo(a)pyrene, acetylaminofluorene, benzidine, and dimethylamino-trans-stilbene, are shown to be activated by liver homogenates to form potent frameshift...

Detection of Mutagenic Activity in Cigarette Smoke Condensates

Kier, Larry D., Yamasaki, Edith, Ames, Bruce N.

The Salmonella typhimurium microsomal test system for mutagenic activity was successfully used to detect the presence of mutagenic compounds in the smoke condensates of several types of cigarettes....

γ-Tocopherol or combinations of vitamin E forms induce cell death in human prostate cancer cells by interrupting sphingolipid synthesis

Jiang, Qing, Wong, Jeffrey, Fyrst, Henrik, Saba, Julie D., Ames, Bruce N.

γ-Tocopherol (γT), the predominant form of vitamin E in diets, but not α-tocopherol, the major vitamin E form in tissues and supplements, inhibits proliferation of prostate cancer cells (LNCaP and...

Increasing longevity by tuning up metabolism

Ames, Bruce N.

To maximize human health and lifespan, scientists must abandon outdated models of micronutrients

A carcinogenic potency database of the standardized results of animal bioassays

Gold, Lois Swirsky, Sawyer, Charles B., Magaw, Renae, Backman, Georganne M., De Veciana, Margarita, Levinson, Robert, ...

The preceding paper described our numerical index of carcinogenic potency, the TD50 and the statistical procedures adopted for estimating it from experimental data. This paper presents the...

A method for detecting abasic sites in living cells: Age-dependent changes in base excision repair

Atamna, Hani, Cheung, Ivana, Ames, Bruce N.

Apurinic/apyrimidinic (AP) sites are common DNA lesions that arise from spontaneous depurination or by base excision repair (BER) of modified bases. A biotin-containing aldehyde-reactive probe (ARP)...

γ-Tocopherol and its major metabolite, in contrast to α-tocopherol, inhibit cyclooxygenase activity in macrophages and epithelial cells

Jiang, Qing, Elson-Schwab, Ilan, Courtemanche, Chantal, Ames, Bruce N.

Cyclooxygenase-2 (COX-2)-catalyzed synthesis of prostaglandin E2 (PGE2) plays a key role in inflammation and its associated diseases, such as cancer and vascular heart disease. Here we report that...

DNA oxidation matters: The HPLC–electrochemical detection assay of 8-oxo-deoxyguanosine and 8-oxo-guanine

Helbock, Harold J., Beckman, Kenneth B., Shigenaga, Mark K., Walter, Patrick B., Woodall, Alan A., Yeo, Helen C., ...

Oxidative DNA damage is important in aging and the degenerative diseases of aging such as cancer. Estimates commonly rely on measurements of 8-oxo-2′-deoxyguanosine (oxo8dG), an adduct that occurs...

Mitochondrial decay in hepatocytes from old rats: Membrane potential declines, heterogeneity and oxidants increase

Hagen, Tory M., Yowe, David L., Bartholomew, James C., Wehr, Carol M., Do, Katherine L., Park, Jin-Y., ...

Mitochondrial function during aging was assessed in isolated rat hepatocytes to avoid the problem of differential lysis when old, fragile mitochondria are isolated. Rhodamine 123, a fluorescent dye...

Inflammation and NOx-induced nitration: Assay for 3-nitrotyrosine by HPLC with electrochemical detection

Shigenaga, Mark K., Lee, Ho H., Blount, Benjamin C., Christen, Stephan, Shigeno, Eric T., Yip, Helena, ...

The identification of 15N-labeled 3-nitrotyrosine (NTyr) by gas chromatography/mass spectroscopy in protein hydrolyzates from activated RAW 264.7 macrophages incubated with 15N-l-arginine confirms...

γ-Tocopherol traps mutagenic electrophiles such as NOx and complements α-tocopherol: Physiological implications

Christen, Stephan, Woodall, Alan A., Shigenaga, Mark K., Southwell-Keely, Peter T., Duncan, Mark W., Ames, Bruce N.

Peroxynitrite, a powerful mutagenic oxidant and nitrating species, is formed by the near diffusion-limited reaction of ·NO and O2⨪ during activation of phagocytes. Chronic inflammation induced by...

Folate deficiency causes uracil misincorporation into human DNA and chromosome breakage: Implications for cancer and neuronal damage

Blount, Benjamin C., Mack, Matthew M., Wehr, Carol M., MacGregor, James T., Hiatt, Robert A., Wang, Gene, ...

Folate deficiency causes massive incorporation of uracil into human DNA (4 million per cell) and chromosome breaks. The likely mechanism is the deficient methylation of dUMP to dTMP and subsequent...

Acetyl-l-carnitine fed to old rats partially restores mitochondrial function and ambulatory activity

Hagen, Tory M., Ingersoll, Russell T., Wehr, Carol M., Lykkesfeldt, Jens, Vinarsky, Vladimir, Bartholomew, James C., ...

Mitochondrial function and ambulatory activity were monitored after feeding old rats acetyl-l-carnitine (ALCAR). Young (3–5 mo) and old (22–28 mo) rats were given a 1.5% (wt/vol) solution of...

Feeding acetyl-l-carnitine and lipoic acid to old rats significantly improves metabolic function while decreasing oxidative stress

Hagen, Tory M., Liu, Jiankang, Lykkesfeldt, Jens, Wehr, Carol M., Ingersoll, Russell T., Vinarsky, Vladimir, ...

Mitochondrial-supported bioenergetics decline and oxidative stress increases during aging. To address whether the dietary addition of acetyl-l-carnitine [ALCAR, 1.5% (wt/vol) in the drinking water]...

Age-associated mitochondrial oxidative decay: Improvement of carnitine acetyltransferase substrate-binding affinity and activity in brain by feeding old rats acetyl-l- carnitine and/or R-α-lipoic acid

Liu, Jiankang, Killilea, David W., Ames, Bruce N.

We test whether the dysfunction with age of carnitine acetyltransferase (CAT), a key mitochondrial enzyme for fuel utilization, is due to decreased binding affinity for substrate and whether this...

Iron deficiency and iron excess damage mitochondria and mitochondrial DNA in rats

Walter, Patrick B., Knutson, Mitchell D., Paler-Martinez, Andres, Lee, Sonia, Xu, Yu, Viteri, Fernando E., ...

Approximately two billion people, mainly women and children, are iron deficient. Two studies examined the effects of iron deficiency and supplementation on rats. In study 1, mitochondrial functional...

Memory loss in old rats is associated with brain mitochondrial decay and RNA/DNA oxidation: Partial reversal by feeding acetyl-l-carnitine and/or R-α-lipoic acid

Liu, Jiankang, Head, Elizabeth, Gharib, Afshin M., Yuan, Wenjun, Ingersoll, Russell T., Hagen, Tory M., ...

Accumulation of oxidative damage to mitochondria, protein, and nucleic acid in the brain may lead to neuronal and cognitive dysfunction. The effects on cognitive function, brain mitochondrial...

Heme deficiency may be a factor in the mitochondrial and neuronal decay of aging

Atamna, Hani, Killilea, David W., Killilea, Alison Nisbet, Ames, Bruce N.

Heme, a major functional form of iron in the cell, is synthesized in the mitochondria by ferrochelatase inserting ferrous iron into protoporphyrin IX. Heme deficiency was induced with...

Histidyl-Transfer Ribonucleic Acid Synthetase Mutants Requiring a High Internal Pool of Histidine for Growth

Straus, Daniel S., Ames, Bruce N.

Mutants that require histidine due to an altered structural gene for the histidyl-transfer ribonucleic acid synthetase (hisS) have been isolated by a general selection for histidine-requiring strains...

Enriched Selection of Dominant Mutations: Histidine Operator Mutations

Chang, George W., Straus, Daniel, Ames, Bruce N.

In the course of selection of bacteria with derepressed levels of histidine biosynthetic enzymes, it was found that when mutagen-treated cells were spread on a selective medium without allowing...

Salmonella typhimurium Mutants with Alternate Requirements for Vitamin B6 or Isoleucine

Guirard, Beverly M., Ames, Bruce N., Snell, Esmond E.

Several mutants of Salmonella typhimurium LT-2, isolated as auxotrophs for vitamin B6, grew without the added vitamin when supplied with either isoleucine, α-ketobutyrate, or...

Histidine Regulation in Salmonella typhimurium VIII. Mutations of the hisT Gene

Chang, George W., Roth, John R., Ames, Bruce N.

The hisT gene, one of six genes in which mutation causes derepression of the histidine operon in Salmonella typhimurium, is shown to code for a protein that is not essential for the growth of the...

Iron Uptake in Salmonella typhimurium: Utilization of Exogenous Siderochromes as Iron Carriers

Luckey, Mary, Pollack, Jay R., Wayne, Rush, Ames, Bruce N., Neilands, J. B.

Aerobic microorganisms have evolved a variety of siderochromes, special ligands which can dissolve insoluble ferric iron and facilitate its transport into the cell. We have found that enb mutants of...

Procedure for Identifying Nonsense Mutations

Berkowitz, David, Hushon, Judith M., Whitfield, Harvey J., Roth, John, Ames, Bruce N.

A method has been devised for the rapid identification of nonsense mutations (UAG, UAA, UGA codons) in Salmonella. The mutations to be tested are reverted, and the revertants are replica-printed onto...

Iron Transport in Salmonella typhimurium: Mutants Blocked in the Biosynthesis of Enterobactin

Pollack, J. R., Ames, Bruce N., Neilands, J. B.

A number of mutants of Salmonella typhimurium were isolated which are blocked in the biosynthesis of enterobactin, an iron chelator that is secreted by the wild-type bacteria when they are grown on...

Compounds Which Serve as the Sole Source of Carbon or Nitrogen for Salmonella typhimurium LT-2

Gutnick, David, Calvo, Joseph M., Klopotowski, Tadeusz, Ames, Bruce N.

About 600 compounds were screened as possible carbon or nitrogen sources for Salmonella typhimurium LT-2. About 100 utilizable compounds were found.

A Simple Method for the Detection of Mutagens in Urine: Studies with the Carcinogen 2-Acetylaminofluorene

Durston, William E., Ames, Bruce N.

We described previously a simple test on petri plates for detecting many carcinogens as mutagens using an especially sensitive set of bacterial strains to detect mutagens and a rat, or human, liver...

Pleiotropy of hisT Mutants Blocked in Pseudouridine Synthesis in tRNA: Leucine and Isoleucine-V aline Operons

Cortese, Riccardo, Landsberg, Raymond, Vonder Haar, R. A., Umbarger, H. E., Ames, Bruce N.

The hisT gene codes for an enzyme responsible for the conversion of uridine to pseudouridine (Ψ) in the anticodon region of many tRNA species in Salmonella typhimurium. We have previously shown that...

Adenosine 3′:5′-Cyclic Monophosphate Concentration in the Bacterial Host Regulates the Viral Decision between Lysogeny and Lysis

Hong, Jen-Shiang, Smith, Gerald R., Ames, Bruce N.

Mutants of Salmonella typhimurium defective in adenylate cyclase (cya gene) or in cAMP receptor protein (crp gene) are lysogenized at reduced frequency by phage P22. One class of the bacterial...

Localized Mutagenesis of Any Specific Small Region of the Bacterial Chromosome

Hong, Jen-Shiang, Ames, Bruce N.

A method, which we call localized mutagenesis, is described for the isolation of temperature-sensitive and other types of mutations in any specific small region (about 1%) of the bacterial...

Carcinogens as Frameshift Mutagens: Metabolites and Derivatives of 2-Acetylaminofluorene and Other Aromatic Amine Carcinogens

Ames, Bruce N., Gurney, E. G., Miller, James A., Bartsch, H.

Several carcinogenic metabolites of the carcinogen 2-acetyl-aminofluorene, especially 2-nitrosofluorene and N-hydroxy-2-aminofluorene, are potent frameshift mutagens for Salmonella typhimurium....

Illicit Transport: The Oligopeptide Permease

Ames, Bruce N., Ames, Giovanna Ferro-Luzzi, Young, Janis Dillaha, Tsuchiya, Dorinne, Lecocq, Jean

The oligopeptide permease of Escherichia coli has been characterized by Payne, Gilvarg, and their colleagues. We have confirmed its existence in Salmonella typhimurium, and have isolated a series of...

An Improved Bacterial Test System for the Detection and Classification of Mutagens and Carcinogens

Ames, Bruce N., Lee, Frank D., Durston, William E.

We previously described a set of four strains of Salmonella typhimurium designed for detecting the various types of mutagens, and showed their utility in detecting a wide variety of carcinogens as...

Carcinogens are Mutagens: A Simple Test System Combining Liver Homogenates for Activation and Bacteria for Detection

Ames, Bruce N., Durston, William E., Yamasaki, Edith, Lee, Frank D.

18 Carcinogens, including aflatoxin B1, benzo(a)pyrene, acetylaminofluorene, benzidine, and dimethylamino-trans-stilbene, are shown to be activated by liver homogenates to form potent frameshift...

Detection of Mutagenic Activity in Cigarette Smoke Condensates

Kier, Larry D., Yamasaki, Edith, Ames, Bruce N.

The Salmonella typhimurium microsomal test system for mutagenic activity was successfully used to detect the presence of mutagenic compounds in the smoke condensates of several types of cigarettes....

γ-Tocopherol or combinations of vitamin E forms induce cell death in human prostate cancer cells by interrupting sphingolipid synthesis

Jiang, Qing, Wong, Jeffrey, Fyrst, Henrik, Saba, Julie D., Ames, Bruce N.

γ-Tocopherol (γT), the predominant form of vitamin E in diets, but not α-tocopherol, the major vitamin E form in tissues and supplements, inhibits proliferation of prostate cancer cells (LNCaP and...

Increasing longevity by tuning up metabolism

Ames, Bruce N.

To maximize human health and lifespan, scientists must abandon outdated models of micronutrients

A carcinogenic potency database of the standardized results of animal bioassays

Gold, Lois Swirsky, Sawyer, Charles B., Magaw, Renae, Backman, Georganne M., De Veciana, Margarita, Levinson, Robert, ...

The preceding paper described our numerical index of carcinogenic potency, the TD50 and the statistical procedures adopted for estimating it from experimental data. This paper presents the...

Low micronutrient intake may accelerate the degenerative diseases of aging through allocation of scarce micronutrients by triage

Ames, Bruce N.

Inadequate dietary intakes of vitamins and minerals are widespread, most likely due to excessive consumption of energy-rich, micronutrient-poor, refined food. Inadequate intakes may result in chronic...

Magnesium deficiency accelerates cellular senescence in cultured human fibroblasts

Killilea, David W., Ames, Bruce N.

Magnesium inadequacy affects more than half of the U.S. population and is associated with increased risk for many age-related diseases, yet the underlying mechanisms are unknown. Altered cellular...