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Grúz P, Yasui M, Ukai A, Horibata K, Honma M, Sugiyama KI. Potent mutagenicity of an azide, 3-azido-1,2-propanediol, in human TK6 cells. Mutat Res Genet Toxicol Environ Mutagen 2022; 876-877:503475. [PMID: 35483777 DOI: 10.1016/j.mrgentox.2022.503475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/17/2022] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
Sodium azide is a strong mutagen that has been successfully employed in mutation breeding of crop plants. In biological systems, it is metabolically converted to the proximate mutagen azidoalanine, which requires further bioactivation to a putative ultimate mutagen that remains elusive. The nature of the DNA modifications induced by azides leading to mutations is also unknown. Other mutagenic organic azido compounds seem to share the same bioactivation pathway to the ultimate mutagenic species as they induce point mutations dependent on the same DNA repair pathways. We investigated mutations induced by the representative mutagen 3-azido-1,2-propanediol (azidoglycerol, AZG) in the human TK6 cell line. Until now, azides have been considered to be non-mutagens and non-carcinogens in mammals, including humans, as judged only by the conventional clastogenicity chromosomal aberration types of bioassays. Here, we show the potent mutagenicity of AZG in cultured human cells, comparable to alkylating agents such as methyl methanesulfonate at concentrations with similar lethality. The potent ability of an organic azide to induce base substitutions in a mammalian system raises an alert with respect to human exposure to organic and inorganic azido compounds.
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Affiliation(s)
- Petr Grúz
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan.
| | - Manabu Yasui
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
| | - Akiko Ukai
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
| | - Katsuyoshi Horibata
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
| | - Masamitsu Honma
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
| | - Kei-Ichi Sugiyama
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
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Fankhauser D, Alissandratos A, Liutkus M, Easton CJ. Easy Production of "Difficult Peptides" Using Cell-Free Protein Synthesis and a New Methionine Analogue as a Latent Peptide Cleavage Site. Chemistry 2021; 27:17487-17494. [PMID: 34651362 DOI: 10.1002/chem.202103161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Indexed: 11/08/2022]
Abstract
Aliphatic γ-chloro-α-amino acids incorporated in place of their canonical analogues through cell-free protein synthesis act as heat-labile linkers, offering a useful strategy for the straightforward production of target peptides as fusion proteins, from which the targets are readily released. Until now, the natural abundance of aliphatic amino acids in peptides has limited the scope of the method, as it leads to undesired cleavage sites in synthesized products, but here the authors report the development of a new cleavable chloro amino acid that incorporates in place of the relatively rare amino acid methionine, thus greatly expanding the scope of producible targets. This new strategy is employed for simplified peptide synthesis with a methionine-free fusion partner, allowing single-site incorporation of the cleavable linker for clean release and easy purification of the target peptide. Its utility is demonstrated through the straightforward preparation of two peptides reported to be challenging targets and not accessible through standard solid-phase chemical methodologies, as well as analogues.
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Affiliation(s)
- Daniel Fankhauser
- Research School of Chemistry, Australian National University, 137 Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Apostolos Alissandratos
- Research School of Chemistry, Australian National University, 137 Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Mantas Liutkus
- Research School of Chemistry, Australian National University, 137 Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Christopher J Easton
- Research School of Chemistry, Australian National University, 137 Sullivans Creek Road, Acton, ACT 2601, Australia
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3
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Grúz P, Sassa A, Hosoda A, Yamagishi H, Usui Y, Shimizu M. Exclusive induction of G:C to A:T transitions by 3-azido-1,2-propanediol in yeast. Mutat Res Genet Toxicol Environ Mutagen 2014; 760:73-6. [PMID: 24211442 DOI: 10.1016/j.mrgentox.2013.10.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/18/2013] [Accepted: 10/28/2013] [Indexed: 11/22/2022]
Abstract
Sodium azide is a strong mutagen which has been successfully employed in mutation breeding of crop plants. In biological systems, it is metabolized to azidoalanine, but further bioactivation to a putative ultimate mutagen as well as the nature of the induced DNA modifications leading to mutations remain elusive. In this study, mutations induced in the CAN1 gene of yeast Saccharomyces cerevisiae by the representative mutagen 3-azido-1,2-propanediol (azidoglycerol, AZG) have been sequenced. Analysis of the forward mutation spectrum to canavanine resistance revealed that AZG induced nearly exclusively G:C to A:T transitions. AZG also induced reversions to tryptophan prototrophy by base-pair substitutions in a dose-dependent manner. This unusual mutational specificity may be shared by other organic azido compounds.
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Abstract
A concise and highly efficient synthetic route to L-azidohomoalanine (L-Aha) and its homologues is presented here. These chemically modified amino acids are used for the introduction of bioorthogonal handles into proteins. The described route avoids major problems of previously reported methods including expensive starting materials, low efficiency, and lack of scalability. Starting from inexpensive N-Boc-O-Bn-L-aspartic acid, gram quantities of L-Aha hydrochloride can be prepared with high purity. The reactions can be completed within 1 week and the products can be incorporated into proteins using L-methionine auxotrophs.
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Strable E, Prasuhn DE, Udit AK, Brown S, Link AJ, Ngo JT, Lander G, Quispe J, Potter CS, Carragher B, Tirrell DA, Finn MG. Unnatural amino acid incorporation into virus-like particles. Bioconjug Chem 2008; 19:866-75. [PMID: 18318461 PMCID: PMC2713011 DOI: 10.1021/bc700390r] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Virus-like particles composed of hepatitis B virus (HBV) or bacteriophage Qbeta capsid proteins have been labeled with azide- or alkyne-containing unnatural amino acids by expression in a methionine auxotrophic strain of E. coli. The substitution does not affect the ability of the particles to self-assemble into icosahedral structures indistinguishable from native forms. The azide and alkyne groups were addressed by Cu(I)-catalyzed [3 + 2] cycloaddition: HBV particles were decomposed by the formation of more than 120 triazole linkages per capsid in a location-dependent manner, whereas Qbeta suffered no such instability. The marriage of these well-known techniques of sense-codon reassignment and bioorthogonal chemical coupling provides the capability to construct polyvalent particles displaying a wide variety of functional groups with near-perfect control of spacing.
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Merkel L, Cheburkin Y, Wiltschi B, Budisa N. In Vivo Chemoenzymatic Control of N-Terminal Processing in Recombinant Human Epidermal Growth Factor. Chembiochem 2007; 8:2227-32. [DOI: 10.1002/cbic.200700540] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
The azide functional group has assumed a prominent role in chemical biology efforts in recent years. Azides may be readily introduced into proteins upon replacement of methionine residues with the non-canonical amino acid azidohomoalanine (AHA). This protocol describes a synthetic route to AHA based on the copper-catalyzed conversion of amines to azides. An alternate protocol for the preparation of AHA is presented in a companion paper. The synthesis and purification of AHA via the route described herein can be completed in 3-4 days.
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Affiliation(s)
- A James Link
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91106, USA.
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Abstract
This protocol describes a synthetic route to the non-canonical amino acid azidohomoalanine (AHA) using protected homoserine as a starting material. An alternative route to AHA is presented in a companion paper. This synthesis can be completed in 5 days.
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Affiliation(s)
- A James Link
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91106, USA.
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Kudaj A, Olma A. An efficient synthesis of optically pure α-alkyl-β-azido- and α-alkyl-β-aminoalanines via ring opening of 3-amino-3-alkyl-2-oxetanones. Tetrahedron Lett 2007; 48:6794-7. [DOI: 10.1016/j.tetlet.2007.07.078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Dieterich DC, Lee JJ, Link AJ, Graumann J, Tirrell DA, Schuman EM. Labeling, detection and identification of newly synthesized proteomes with bioorthogonal non-canonical amino-acid tagging. Nat Protoc 2007; 2:532-40. [PMID: 17406607 DOI: 10.1038/nprot.2007.52] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A major aim of proteomics is the identification of proteins in a given proteome at a given metabolic state. This protocol describes the step-by-step labeling, purification and detection of newly synthesized proteins in mammalian cells using the non-canonical amino acid azidohomoalanine (AHA). In this method, metabolic labeling of newly synthesized proteins with AHA endows them with the unique chemical functionality of the azide group. In the subsequent click chemistry tagging reaction, azide-labeled proteins are covalently coupled to an alkyne-bearing affinity tag. After avidin-based affinity purification and on-resin trypsinization, the resulting peptide mixture is subjected to tandem mass spectrometry for identification. In combination with deuterated leucine-based metabolic colabeling, candidate proteins can be immediately validated. Bioorthogonal non-canonical amino-acid tagging can be combined with any subcellular fractionation, immunopurification or other proteomic method to identify specific subproteomes, thereby reducing sample complexity and enabling the identification of subtle changes in a proteome. This protocol can be completed in 5 days.
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Affiliation(s)
- Daniela C Dieterich
- Division of Biology, Howard Hughes Medical Institute, California Institute of Technology, Pasadena, California 91125, USA.
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Abstract
Detection of metabolites and post-translational modifications can be achieved using the azide as a bioorthogonal chemical reporter. Once introduced into target biomolecules, either metabolically or through chemical modification, the azide can be tagged with probes using one of three highly selective reactions: the Staudinger ligation, the Cu(I)-catalyzed azide-alkyne cycloaddition, or the strain-promoted [3 + 2] cycloaddition. Here, we compared these chemistries in the context of various biological applications, including labeling of biomolecules in complex lysates and on live cell surfaces. The Cu(I)-catalyzed reaction was found to be most efficient for detecting azides in protein samples but was not compatible with live cells due to the toxicity of the reagents. Both the Staudinger ligation and the strain-promoted [3 + 2] cycloaddition using optimized cyclooctynes were effective for tagging azides on live cells. The best reagent for this application was dependent upon the specific structure of the azide. These results provide a guide for biologists in choosing a suitable ligation chemistry.
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Link AJ, Vink MKS, Agard NJ, Prescher JA, Bertozzi CR, Tirrell DA. Discovery of aminoacyl-tRNA synthetase activity through cell-surface display of noncanonical amino acids. Proc Natl Acad Sci U S A 2006; 103:10180-10185. [PMID: 16801548 PMCID: PMC1502431 DOI: 10.1073/pnas.0601167103] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The incorporation of noncanonical amino acids into recombinant proteins in Escherichia coli can be facilitated by the introduction of new aminoacyl-tRNA synthetase activity into the expression host. We describe here a screening procedure for the identification of new aminoacyl-tRNA synthetase activity based on the cell surface display of noncanonical amino acids. Screening of a saturation mutagenesis library of the E. coli methionyl-tRNA synthetase (MetRS) led to the discovery of three MetRS mutants capable of incorporating the long-chain amino acid azidonorleucine into recombinant proteins with modest efficiency. The Leu-13 --> Gly (L13G) mutation is found in each of the three MetRS mutants, and the MetRS variant containing this single mutation is highly efficient in producing recombinant proteins that contain azidonorleucine.
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Affiliation(s)
- A James Link
- *Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Mandy K S Vink
- *Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Nicholas J Agard
- Departments of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720; and
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Jennifer A Prescher
- Departments of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720; and
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Carolyn R Bertozzi
- Departments of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720; and
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - David A Tirrell
- *Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125;
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Dieterich DC, Link AJ, Graumann J, Tirrell DA, Schuman EM. Selective identification of newly synthesized proteins in mammalian cells using bioorthogonal noncanonical amino acid tagging (BONCAT). Proc Natl Acad Sci U S A 2006; 103:9482-7. [PMID: 16769897 PMCID: PMC1480433 DOI: 10.1073/pnas.0601637103] [Citation(s) in RCA: 596] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In both normal and pathological states, cells respond rapidly to environmental cues by synthesizing new proteins. The selective identification of a newly synthesized proteome has been hindered by the basic fact that all proteins, new and old, share the same pool of amino acids and thus are chemically indistinguishable. We describe here a technology, based on the cotranslational introduction of azide groups into proteins and the chemoselective tagging of azide-labeled proteins with an alkyne affinity tag, to separate and identify, specifically, the newly synthesized proteins in mammalian cells. Incorporation of the azide-bearing amino acid azidohomoalanine is unbiased, not toxic, and does not increase protein degradation. As a first demonstration of the method, we report the selective purification and identification of 195 metabolically labeled proteins with multidimensional liquid chromatography in-line with tandem MS. Furthermore, in combination with leucine-based mass tagging, candidates were immediately validated as newly synthesized proteins. The identified proteins, synthesized in a 2-h window, possess a broad range of biochemical properties and span most functional gene ontology categories. This technology makes it possible to address the temporal and spatial characteristics of newly synthesized proteomes in any cell type.
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Affiliation(s)
| | - A. James Link
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | | | - David A. Tirrell
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Erin M. Schuman
- *Division of Biology, Howard Hughes Medical Institute, and
- To whom correspondence should be addressed. E-mail:
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Kiick KL, Saxon E, Tirrell DA, Bertozzi CR. Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation. Proc Natl Acad Sci U S A 2002; 99:19-24. [PMID: 11752401 PMCID: PMC117506 DOI: 10.1073/pnas.012583299] [Citation(s) in RCA: 703] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2001] [Accepted: 10/31/2001] [Indexed: 11/18/2022] Open
Abstract
The introduction of chemically unique groups into proteins by means of non-natural amino acids has numerous applications in protein engineering and functional studies. One method to achieve this involves the utilization of a non-natural amino acid by the cell's native translational apparatus. Here we demonstrate that a methionine surrogate, azidohomoalanine, is activated by the methionyl-tRNA synthetase of Escherichia coli and replaces methionine in proteins expressed in methionine-depleted bacterial cultures. We further show that proteins containing azidohomoalanine can be selectively modified in the presence of other cellular proteins by means of Staudinger ligation with triarylphosphine reagents. Incorporation of azide-functionalized amino acids into proteins in vivo provides opportunities for protein modification under native conditions and selective labeling of proteins in the intracellular environment.
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Affiliation(s)
- Kristi L Kiick
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA 01003, USA
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Abstract
The mutagenic effects of azide (N3-) anion in bacterial test systems require the formation of the novel mutagenic metabolite, 3-azido-L-alanine (AZAL). Although the mechanism of AZAL-induced mutagenicity is unknown, subsequent bioactivation of this metabolite appears likely. Earlier studies have shown that other azide-containing amino acids are mutagenic as well. In fact, the mutagenic potency of the synthetic AZAL homologue, L-2-amino-4-azidobutanoic acid (HomoAZAL), was several times that of AZAL. To gain insight into the biochemical processing and mutagenicity of azido amino acids in Salmonella typhimurium, several specifically deuterium-labeled azido amino acids have been prepared and tested for mutagenic potency. In addition, the effect of (aminooxy)acetic acid (AOA) (a potent inhibitor of pyridoxal-dependent processes) on AZAL-induced mutagenesis was examined. The results showed that 2-deuterium substitution of AZAL resulted in a slight increase in mutagenic potency, while AOA treatment resulted in no change in AZAL potency. Taken together these findings did not support the involvement of pyridoxal-dependent processes in AZAL bioactivation. In contrast, deuterium substitution adjacent to the azide group in HomoAZAL and 5-azido-L-norvaline (N3-Norval) resulted in a large decrease in mutagenic potency when compared to the non-deuterium labeled compounds. These observations are consistent with a bioactivation mechanism involving rate-limiting C-H bond cleavage in the formation of the ultimate mutagen. Moreover, this effect of deuterium labeling points to processing of the azide-containing side chain as a key feature in the mutagenic activation mechanism.
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Affiliation(s)
- J B Mangold
- Medicinal Chemistry Program, School of Pharmacy, University of Connecticut, Storrs
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Affiliation(s)
- R J Griffin
- Department of Chemistry, University of Newcastle, Newcastle upon Tyne, U.K
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Grúz P, Jurícek M, Zák P, Velemínský J. Mutagenicity of 3-azido-1,2-propanediol and 9-(3-azido-2-hydroxypropyl)-adenine in repair deficient strains of Escherichia coli. Mutat Res 1993; 303:1-9. [PMID: 7690900 DOI: 10.1016/0165-7992(93)90002-d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The mutagenicity of two non-aromatic organic azido compounds, 3-azido-1,2-propanediol (AG) and 9-(3-azido-2-hydroxypropyl)-adenine (AHPA), was studied in E. coli repair deficient strains uvrA6, uvrA6 + umuC36, uvrA6+ umuC122::Tn5, polA1, tagA1+ alkA1, ada and dam3. The mutagenicity of both agents was markedly enhanced by defects of UvrABC excinuclease (uvrA6) and was independent of umuC function of the SOS error-prone pathway. Neither azido compound promoted umuDC operon expression. The mutagenicity of AG in tag A1, alkA1 and ada mutants does not differ from that found in the wild-type strain. The expression of both ada and alkA genes was not elevated by AG. Experiments on polA1 and dam3 mutants suggest that DNA polymerase I as well as the mutHLS mismatch repair pathway does not contribute to the removal of putative DNA lesions induced by AG.
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Affiliation(s)
- P Grúz
- Department of Genetics, Academy of Sciences of the Czech Republic, Prague
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Juricek M, Gruz P, Veleminsky J, Stanek J, Kefurt K, Moravcova J, Jary J. Mutagenic activity of 6-azido deoxyhexoses and azido alcohols in Salmonella typhimurium and its inhibition by a structure-similar carbon source in the medium. Mutat Res 1991; 251:13-20. [PMID: 1944370 DOI: 10.1016/0027-5107(91)90211-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
6-Azido-6-deoxy (AZd) derivatives of D-glucose, D-mannose, D-altrose, D-allose, L-idose, D-galactose, D-galactonic acid and D-galactitol, 3-azido-1,2-propanediol (azidoglycerol), 3,1-diazido-2-propanol (diazidoglycerol) and (at much higher doses) 2-azidoethanol were mutagenic in Salmonella typhimurium strains TA100 and TA1535. The mutagenic response was similar to that induced by sodium azide, i.e., the azido compounds failed to induce mutations in strain TA98, and mutagenesis was independent of plasmid pKM101, and independent of external activation. The specific mutagenicity (his+ rev/mmole) of AZd-glucose and AZd-galactose was decreased with increasing concentrations of D-glucose or D-galactose in the minimal agar medium and enhanced 100-fold or more when 0.2% citrate rather than 0.2% glucose served as the carbon source in the medium. Similarly, the mutagenic efficiency of azidoglycerol was inhibited by glycerol but not by D-glucose or D-galactose; however, the mutagenicity of sodium azide was not influenced by any of these carbon sources in the medium. The inhibition of the mutagenic action of azido hexoses and azido alcohols by non-azido structural analogs is assumed to reside in competition in transmembrane transport or for the metabolic pathways.
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Affiliation(s)
- M Juricek
- Institute of Experimental Botany, Czechoslovak Academy of Sciences, Prague
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