1
|
de Melo GD, Coatnoan N, Gouault N, Cupif JF, Renault J, Cosson A, Uriac P, Blondel A, Minoprio P. Prodrugs as new therapies against Chagas disease: In vivo synergy between Trypanosoma cruzi proline racemase inhibitors and benznidazole: TcPRAC inhibitor prodrugs against Chagas disease. J Glob Antimicrob Resist 2021; 28:84-89. [PMID: 34929377 DOI: 10.1016/j.jgar.2021.10.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 10/04/2021] [Accepted: 10/21/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Chagas disease, caused by the parasitic protozoan Trypanosoma cruzi, affects approximately 6-7 million people worldwide. There are limited available therapies, and they exhibit low efficacy, often high toxicity in chronic cases and some drug resistance. In this study, our objective was to develop ester prodrugs that inhibit proline racemase (TcPRAC), a parasitic enzyme that we have previously identified and characterized as a promising target because of its essential role in the parasite's life cycle and virulence, and to test their activity against T. cruzi. METHOD Using structural bioinformatics, we modelled several functional intermediates of the catalytic site between the opened and closed conformations of TcPRAC based on its crystal structures in complex with its competitive inhibitor, pyrrole-2-carboxylic acid. Guided by these intermediates, which were later validated in cocrystals, we designed and evaluated numerous compounds and tested them enzymatically on live parasites and in mice with our quick and straightforward drug screening method, which is based on state-of-the-art bioluminescent T. cruzi parasites injected subcutaneously. RESULTS Some of our novel compounds specifically inhibited racemase activity, as determined through biochemical assays, and covalently bound to TcPRAC. Furthermore, the corresponding ester prodrugs were effective in killing parasites in vitro. Bioluminescent T. cruzi assays in mice showed that JR1531, a TcPRAC inhibitor prodrug, can kill parasites in living animals, with boosted action when combined with low doses of benznidazole. CONCLUSIONS This approach, based on TcPRAC inhibitor prodrugs in association with low doses of benznidazole, may lead to a more effective, specific and nontoxic therapy against Chagas disease.
Collapse
Affiliation(s)
- Guilherme Dias de Melo
- Institut Pasteur, Département Santé Globale, Laboratoire des Processus Infectieux à Trypanosomatidés, 28 rue du Dr Roux, 75015 Paris, France
| | - Nicolas Coatnoan
- Institut Pasteur, Département Santé Globale, Laboratoire des Processus Infectieux à Trypanosomatidés, 28 rue du Dr Roux, 75015 Paris, France
| | - Nicolas Gouault
- Université de Rennes 1, Equipe Chimie organique et interfaces (CORINT), UMR 6226 Sciences Chimiques de Rennes, 2 Avenue du Pr. Léon Bernard, 35043 Rennes, France
| | - Jean-François Cupif
- Université de Rennes 1, Equipe Chimie organique et interfaces (CORINT), UMR 6226 Sciences Chimiques de Rennes, 2 Avenue du Pr. Léon Bernard, 35043 Rennes, France
| | - Jacques Renault
- Université de Rennes 1, Equipe Chimie organique et interfaces (CORINT), UMR 6226 Sciences Chimiques de Rennes, 2 Avenue du Pr. Léon Bernard, 35043 Rennes, France
| | - Alain Cosson
- Institut Pasteur, Département Santé Globale, Laboratoire des Processus Infectieux à Trypanosomatidés, 28 rue du Dr Roux, 75015 Paris, France
| | - Philippe Uriac
- Université de Rennes 1, Equipe Chimie organique et interfaces (CORINT), UMR 6226 Sciences Chimiques de Rennes, 2 Avenue du Pr. Léon Bernard, 35043 Rennes, France.
| | - Arnaud Blondel
- Institut Pasteur, Département de Biologie Structurale et Chimie, Unité de Bioinformatique Structurale, CNRS-UMR 3528, 28 rue du Dr Roux, 75015 Paris, France.
| | - Paola Minoprio
- Institut Pasteur, Département Santé Globale, Laboratoire des Processus Infectieux à Trypanosomatidés, 28 rue du Dr Roux, 75015 Paris, France.
| |
Collapse
|
2
|
Revelles O, Espinosa-Urgel M, Fuhrer T, Sauer U, Ramos JL. Multiple and interconnected pathways for L-lysine catabolism in Pseudomonas putida KT2440. J Bacteriol 2005; 187:7500-10. [PMID: 16237033 PMCID: PMC1272968 DOI: 10.1128/jb.187.21.7500-7510.2005] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Accepted: 08/24/2005] [Indexed: 11/20/2022] Open
Abstract
L-lysine catabolism in Pseudomonas putida KT2440 was generally thought to occur via the aminovalerate pathway. In this study we demonstrate the operation of the alternative aminoadipate pathway with the intermediates D-lysine, L-pipecolate, and aminoadipate. The simultaneous operation of both pathways for the use of L-lysine as the sole carbon and nitrogen source was confirmed genetically. Mutants with mutations in either pathway failed to use L-lysine as the sole carbon and nitrogen source, although they still used L-lysine as the nitrogen source, albeit at reduced growth rates. New genes were identified in both pathways, including the davB and davA genes that encode the enzymes involved in the oxidation of L-lysine to delta-aminovaleramide and the hydrolysis of the latter to delta-aminovalerate, respectively. The amaA, dkpA, and amaB genes, in contrast, encode proteins involved in the transformation of Delta1-piperidine-2-carboxylate into aminoadipate. Based on L-[U-13C, U-15N]lysine experiments, we quantified the relative use of pathways in the wild type and its isogenic mutants. The fate of 13C label of L-lysine indicates that in addition to the existing connection between the D- and L-lysine pathways at the early steps of the catabolism of L-lysine mediated by a lysine racemase, there is yet another interconnection at the lower end of the pathways in which aminoadipate is channeled to yield glutarate. This study establishes an unequivocal relationship between gene and pathway enzymes in the metabolism of L-lysine, which is of crucial importance for the successful colonization of the rhizosphere of plants by this microorganism.
Collapse
Affiliation(s)
- Olga Revelles
- Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, C/Prof. Albareda 1, 18008 Granada, Spain
| | | | | | | | | |
Collapse
|
3
|
Wilms B, Hauck A, Reuss M, Syldatk C, Mattes R, Siemann M, Altenbuchner J. High-cell-density fermentation for production of L-N-carbamoylase using an expression system based on the Escherichia coli rhaBAD promoter. Biotechnol Bioeng 2001; 73:95-103. [PMID: 11255157 DOI: 10.1002/bit.1041] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.2] [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: 11/11/2022]
Abstract
A high-cell-density fed-batch fermentation for the production of heterologous proteins in Escherichia coli was developed using the positively regulated Escherichia coli rhaBAD promoter. The expression system was improved by reducing of the amount of expensive L-rhamnose necessary for induction of the rhamnose promoter and by increasing the vector stability. Consumption of the inducer L-rhamnose was inhibited by inactivation of L-rhamnulose kinase encoding gene rhaB of Escherichia coli W3110, responsible for the first irreversible step in rhamnose catabolism. Plasmid instability caused by multimerization of the expression vector in the recombination-proficient W3110 was prevented by insertion of the multimer resolution site cer from the ColE1 plasmid into the vector. Fermentation experiments with the optimized system resulted in the production of 100 g x L(-1) cell dry weight and 3.8 g x L(-1) of recombinant L-N-carbamoylase, an enzyme, which is needed for the production of enantiomeric pure amino acids in a two-step reaction from hydantoins.
Collapse
Affiliation(s)
- B Wilms
- Institut für Industrielle Genetik Universität Stuttgart, Allmandring 31, 70569 Stuttgart, Germany
| | | | | | | | | | | | | |
Collapse
|
4
|
Abstract
The fluorescence probe, 8-anilino-1-naphthalenesulfonic acid (ANS), was used to monitor the induced-fit conformational movement in rabbit muscle adenylate kinase. In 50 mM Tris-HCl buffer (pH 8.1), the time course of ANS binding to rabbit muscle adenylate kinase is a biphasic process. The fast phase completes within the dead-time of the stopped-flow equipment used (about 15 ms), while the slow phase ends in about 10 minutes. In the presence of 2.0 microM peptidyl prolyl cis/trans-isomerase, the rate constant of the slow phase reaction is accelerated about 2.4-fold, suggesting that the domain movement during ANS binding to rabbit muscle adenylate kinase may involve proline isomerization. The activation energy of the slow phase was determined to be 74.6 kJ/mol, which is comparable to the activation energy of proline cis/trans-isomerization (about 80 kJ/mol).
Collapse
Affiliation(s)
- X R Sheng
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica Beijing, China
| | | | | | | | | |
Collapse
|
5
|
Chary VK, de la Fuente JL, Liras P, Martin JF. Amy as a reporter gene for promoter activity in Nocardia lactamdurans: comparison of promoters of the cephamycin cluster. Appl Environ Microbiol 1997; 63:2977-82. [PMID: 9251185 PMCID: PMC168596 DOI: 10.1128/aem.63.8.2977-2982.1997] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [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: 02/05/2023] Open
Abstract
Promoter probe vectors containing the pA origin of replication and the Streptomyces griseus promoterless amy gene (encoding alpha-amylase) as reporter have been constructed to study transcription initiation regions in Nocardia lactamdurans. In some of the promoter probe vectors the phage fd terminator has been introduced to avoid readthrough expression from upstream sequences. By using these vectors, four different transcription initiation regions of the cephamycin gene cluster have been studied in N. lactamdurans. The bla gene encoding a beta-lactamase has a relatively strong promoter. Two other separate promoters corresponding to the lat and cefD genes (encoding, respectively, lysine-6-aminotransferase and isopenicillin N-epimerase) showed weak transcription initiation ability. These two promoters are arranged in a bidirectional transcription initiation region located in the center of the cephamycin gene cluster. The cmcH gene (encoding 3-hydroxymethylcephem carbamoyltransferase) upstream region did not contain a functional promoter, suggesting that cmcH is transcribed as a part of a polycistronic mRNA. The native amy promoter is used very efficiently in N. lactamdurans, resulting in secretion of high levels of extracellular alpha-amylase.
Collapse
Affiliation(s)
- V K Chary
- Faculty of Biology, University of León, Spain
| | | | | | | |
Collapse
|
6
|
Abstract
Formation of lysine from stereoisomers (SI) of 2,6-diaminopimelic acid (DAP) and the epimerization between the three SI of DAP (DAP-SI) by rumen protozoa and bacteria were examined. Mixed rumen protozoa (P) and bacteria (B) were isolated from the rumen of goats given a concentrate and hay cubes and incubated separately with and without a mixture and a single one of the three DAP-SI. In P suspensions, mixed DAP-SI decreased by 10.59% as a whole and converted mainly to lysine by 8.41% during 12 h incubation. When meso-, L- and D-DAP were added singly to the media, the results showed that each DAP-SI interconverted and produced lysine. This means that mixed rumen protozoa have an ability to synthesize lysine from not only meso-DAP but also from D- and L-DAP, though probably via meso-DAP, and hence have DAP epimerase activities for the reversal conversion of each DAP-SI. This is the first discovery to show the interconversion of DAP-SI and synthesis of lysine from them by protozoa. In B suspensions, mixed DAP-SI decreased by 10.92% as a whole and converted to lysine by 4.20% during 12 h incubation. When a single DAP-SI was added to the media, meso-, L- and D-DAP were interconverted and then converted to lysine by the rumen bacteria as well as the protozoa. This also means that mixed rumen bacteria have DAP epimerase activities to interconvert DAP-SI and have an ability to synthesize lysine from not only meso-DAP but also from L- and D-DAP, and this is also the first finding in rumen bacteria.
Collapse
Affiliation(s)
- A M El-Waziry
- Laboratory of Animal Nutrition and Biochemistry, Division of Animal Science, Miyazaki University, Miyazaki 889-21, Japan
| | | |
Collapse
|
7
|
Ahn JH, Walton JD. Chromosomal organization of TOX2, a complex locus controlling host-selective toxin biosynthesis in Cochliobolus carbonum. Plant Cell 1996; 8:887-97. [PMID: 8672886 PMCID: PMC161146 DOI: 10.1105/tpc.8.5.887] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Race 1 isolates of the filamentous fungus Cochliobolus carbonum are exceptionally virulent on certain genotypes of maize due to production of a cyclic tetrapeptide, HC-toxin. In crosses between toxin-producing (Tox2+) and toxin-nonproducing (Tox2-) isolates, toxin production segregates in a simple 1:1 pattern, suggesting the involvement of a single genetic locus, which has been named TOX2. Earlier work had shown that in isolate SB111, TOX2 consists in part of two copies of a gene, HTS1, that encodes a 570-kD cyclic peptide synthetase and is lacking in Tox2- isolates. The genomic structure of TOX2 and the relationship between the two copies of HTS1 have now been clarified by using pulsedfield gel electrophoresis and physical mapping. In isolate SB111, both copies of HTS1 are on the largest chromosome (3.5 Mb), which is not present in the related Tox2- strain SB114. Two other genes known or thought to be important for HC-toxin biosynthesis, TOXA and TOXC, are also on the same chromosome in multiple copies. Other independent Tox2+ isolates also have two linked copies of HTS1, but in some isolates the size of the chromosome containing HTS1 is 2.2 Mb. Evidence obtained with Tox2+ -unique and with random probes is consistent with a reciprocal translocation as the cause of the difference in the size of the HTS1-containing chromosome among the Tox2+ isolates studied here. Physical mapping of the 3.5-Mb chromosome of SB111 that contains HTS1 using rare-cutting restriction enzymes and engineered restriction sites was used to map the chromosome location of the two copies of HTS1 and the three copies of TOXC. The results indicate that TOX2 is a complex locus that extends over more than 500 kb. The capacity to produce HC-toxin did not evolve by any single, simple mechanism.
Collapse
Affiliation(s)
- J H Ahn
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing 48824, USA
| | | |
Collapse
|
8
|
Nikolskaya AN, Panaccione DG, Walton JD. Identification of peptide synthetase-encoding genes from filamentous fungi producing host-selective phytotoxins or analogs. Gene X 1995; 165:207-11. [PMID: 8522177 DOI: 10.1016/0378-1119(95)00555-k] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [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: 01/31/2023] Open
Abstract
Race 1 of Cochliobolus carbonum (Cc) makes a cyclic tetrapeptide, HC-toxin, that is necessary for its virulence on certain genotypes of maize. The synthesis of HC-toxin is catalyzed by a 570-kDa multifunctional enzyme, HC-toxin synthetase (HTS). The gene encoding HTS (HTS1) is absent from other races of Cc and from other species of Cochliobolus. Four other unrelated filamentous fungi make cyclic peptides closely related to HC-toxin, raising the possibility that the corresponding cyclic peptide synthetase (CPS)-encoding genes have moved between these fungi by horizontal gene transfer. Degenerate PCR primers were designed based on several highly conserved amino acid (aa) motifs common to known CPS domains and used to amplify genomic sequences from different fungi. PCR products representing CPS genes from Diheterospora chlamydosporia, which makes the HC-toxin analog chlamydocin, Cylindrocladium macrosporum, which makes the analog Cyl-2, and C. victoriae, which makes the unrelated cyclic pentapeptide victorin, were cloned and analysed. Their sequences are more related to HTS1 than to other cloned CPS, but the percent aa identity is not consistent with very recent horizontal movement of these genes.
Collapse
Affiliation(s)
- A N Nikolskaya
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing 48824, USA
| | | | | |
Collapse
|
9
|
Abstract
The fungal pathogen Cochliobolus carbonum race 1 produces a host-selective toxin (HC-toxin) that is responsible for increased virulence on susceptible genotypes of maize. The toxin is synthesized by a peptide synthetase, which is a product of the HTS1 gene. Because the toxin is not stored in dormant conidia, early expression of HTS1 is crucial for extensive colonization of susceptible leaf tissue. To detect the HTS1 transcript and determine the onset of HTS1 gene expression, we analyzed RNA preparations from ungerminated and germinated conidia by reverse transcription-polymerase chain reaction using oligonucleotide primers within the 15.7-kb open reading frame of HTS1. With primer pairs near both the 3'- and the 5'-termini, amplified products of the HTS1 transcript were detected in RNA prepared from dormant conidia. With all primer pairs used, the quantities of transcript increased substantially during germ tube emergence and elongation, indicating that expression of HTS1 is up regulated during spore germination. Digestion with restriction endonucleases confirmed the identity of the amplified products. Amplification of the constitutively expressed beta-tubulin transcript, which is processed to remove introns, as well as the absence of amplification products with primers spanning the HTS1 coding sequence established that cDNA was amplified and not contaminating genomic DNA.
Collapse
Affiliation(s)
- M J Jones
- U.S. Department of Agriculture, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-1155, USA
| | | |
Collapse
|
10
|
Xu M, Meng W, Ma X. PDI-, PPI- and chaperone-catalyzed refolding of recombinant human IL-2 and GM-CSF. Sci China B 1995; 38:429-37. [PMID: 7786412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The studies on PDI-, PPI- and chaperone-catalyzed refolding of recombinant human IL-2 and GM-CSF show that PDI can prevent the mismatch of disulfide bonds and formation of aggregates by interchains linkage; furthermore, PDI can correct the mismatching of disulfide bonds in IL-2 isomers. PPI can increase the rate of folding reaction while chaperone can prevent the aggregation during the folding process. In addition, there is a synergistic effect between them.
Collapse
Affiliation(s)
- M Xu
- Institute of Basic Medical Sciences, Beijing, China
| | | | | |
Collapse
|
11
|
Chatterjee SP, Singh BK, Gilvarg C. Biosynthesis of lysine in plants: the putative role of meso-diaminopimelate dehydrogenase. Plant Mol Biol 1994; 26:285-90. [PMID: 7948877 DOI: 10.1007/bf00039539] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Extracts from Chlamydomonas, corn, soybean and tobacco were tested for enzymes of the lysine biosynthetic pathway. Dihydrodipicolinic acid (DHD) synthase, DHD reductase, diaminopimelate (DAP) epimerase and DAP decarboxylase were present in all. However, in contrast to the report of Wenko et al., meso-DAP dehydrogenase could not be detected in extracts prepared from soybean. Moreover, it was not found in Chlamydomonas, corn and tobacco as well. In order to set an upper limit to the amount of meso-DAP dehydrogenase that might be present, reconstruction experiments were performed with soybean and corn extracts in which the conversion of dihydrodipicolinate to lysine was made dependent on the addition of limited amounts of the meso-DAP dehydrogenase purified from Bacillus sphaericus. The presence of DAP epimerase and the absence of meso-DAP dehydrogenase indicates that the meso-DAP dehydrogenase abbreviated pathway for lysine synthesis is not operative in plants.
Collapse
Affiliation(s)
- S P Chatterjee
- Department of Molecular Biology, Princeton University, NJ 08544
| | | | | |
Collapse
|
12
|
|
13
|
Richaud C, Mengin-Lecreulx D, Pochet S, Johnson EJ, Cohen GN, Marlière P. Directed evolution of biosynthetic pathways. Recruitment of cysteine thioethers for constructing the cell wall of Escherichia coli. J Biol Chem 1993; 268:26827-35. [PMID: 8262915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We report that expansion of thioether biosynthesis in Escherichia coli generates sulfur-containing amino acids that can replace meso-diaminopimelate, the essential amino acid used for cross-linking the cell wall. This was accomplished by jointly overexpressing the metB gene coding for L-cystathionine gamma-synthase and disrupting the metC gene, whose product, L-cystathionine beta-lyase, is responsible for the destruction of L-cystathionine and other L-cysteine thioethers. As a result, meso-lanthionine and L-allo-cystathionine were produced endogenously and incorporated in the peptidoglycan, thereby enabling E. coli strains auxotrophic for diaminopimelate to grow in its absence. Thus, current techniques of metabolic engineering can be applied to evolving the chemical constitution of living cells beyond its present state.
Collapse
Affiliation(s)
- C Richaud
- Unité de Physiologie Cellulaire, Centre National de la Recherche Scientifique (CNRS URA 1300), Paris, France
| | | | | | | | | | | |
Collapse
|
14
|
Scott-Craig JS, Panaccione DG, Pocard JA, Walton JD. The cyclic peptide synthetase catalyzing HC-toxin production in the filamentous fungus Cochliobolus carbonum is encoded by a 15.7-kilobase open reading frame. J Biol Chem 1992; 267:26044-9. [PMID: 1281482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Race 1 of Cochliobolus carbonum, a fungal plant pathogen, owes its exceptional virulence on certain genotypes of maize to the production of HC-toxin, a cyclic tetrapeptide. Production of HC-toxin is controlled by a single known gene, TOX2. Race 1, but not races that do not make HC-toxin, contains two copies of a 22-kilobase (kb) region of chromosomal DNA that is required for HC-toxin biosynthesis and hence virulence. We have sequenced this 22-kb region and here show that it contains an open reading frame of 15.7 kb that encodes a multifunctional cyclic peptide synthetase of potential M(r)574,620. This gene, called HTS1, apparently contains no introns. The predicted gene product, HC-toxin synthetase (HTS), contains four amino acid-binding (adenylate-forming) domains that are highly similar to those found in other cyclic peptide synthetases and other adenylate-binding enzymes. The DNA sequence encodes tryptic peptides derived from two HC-toxin biosynthetic enzymes, HC-toxin synthetase 1 (HTS-1) and HC-toxin synthetase 2 (HTS-2), indicating that these two enzymes exist in vivo as part of a single polypeptide. Consistent with this, in some enzyme preparations antibodies against the enzyme HTS-2, which was originally purified as a protein with a subunit M(r) of 160,000, recognize a protein with an estimated subunit M(r) greater than 480,000.
Collapse
Affiliation(s)
- J S Scott-Craig
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing 48824
| | | | | | | |
Collapse
|
15
|
Gerhart F, Higgins W, Tardif C, Ducep JB. 2-(4-Amino-4-carboxybutyl)aziridine-2-carboxylic acid. A potent irreversible inhibitor of diaminopimelic acid epimerase. Spontaneous formation from alpha-(halomethyl)diaminopimelic acids. J Med Chem 1990; 33:2157-62. [PMID: 2197412 DOI: 10.1021/jm00170a018] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [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: 12/30/2022]
Abstract
2-(4-Amino-4-carboxybutyl)aziridine-2-carboxylic acid (3) (aziridino-DAP) was identified as the product of spontaneous hydrolysis of alpha-(halomethyl)diaminopimelic acids (alpha-halomethyl-DAPs) 2a-c. Under physiological conditions, 3 is an extremely potent irreversible inhibitor of the bacterial enzyme diaminopimelic acid epimerase (DAP-epimerase; EC 5.1.1.7). This unusual mode of action of an alpha-halomethyl amino acid with a non-pyridoxal enzyme is investigated. Synthesis and characterization of 2a-c and 3, kinetics of spontaneous formation of 3 from alpha-halomethyl-DAPs, and kinetics of enzyme inhibition by both 3 and by alpha-halomethyl-DAPs are reported.
Collapse
Affiliation(s)
- F Gerhart
- Merrell Dow Research Institute, Strasbourg Center, France
| | | | | | | |
Collapse
|
16
|
Higgins W, Tardif C, Richaud C, Krivanek MA, Cardin A. Expression of recombinant diaminopimelate epimerase in Escherichia coli. Isolation and inhibition with an irreversible inhibitor. Eur J Biochem 1989; 186:137-43. [PMID: 2689171 DOI: 10.1111/j.1432-1033.1989.tb15187.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Recombinant diaminopimelate epimerase is overproduced to give 1% of soluble protein when grown under the appropriate conditions in Escherichia coli. This compares with 0.02% of the constitutive level of wild-type enzyme. A new purification procedure now yields milligram quantities of homogeneous enzyme of high specific activity (192 U/mg). This has enabled sufficient amounts of enzyme both to compare with wild-type enzyme and to enable active site modification studies to be performed. Incubation of the enzyme with 2-(4-amino-4-carboxybutyl)-2-aziridine-carboxylic acid (AZIDAP), results in time-dependent irreversible inhibition. Tryptic digestion of the inactivated enzyme and peptide-mapping show that AZIDAP is specifically and covalently bound to the enzyme at a unique peptide. Determination of the amino acid sequence of this peptide and comparison with the sequence deduced from the DNA sequence of the dapF gene shows that Cys73 is labelled. Finally based on limited sequence similarities around this cysteine and active-site cysteines of proline racemase and 1-hydroxyproline 2-epimerase, together with mechanistic considerations, we propose that all three non-pyridoxal-phosphate-containing racemases/epimerases derive from a common evolutionary origin.
Collapse
Affiliation(s)
- W Higgins
- Merrell Dow Research Institute, Strasbourg, France
| | | | | | | | | |
Collapse
|
17
|
Weir AN, Bucke C, Holt G, Lilly MD, Bull AT. A high-performance liquid chromatography method for the simultaneous assay of diaminopimelate epimerase and decarboxylase. Anal Biochem 1989; 180:298-302. [PMID: 2510546 DOI: 10.1016/0003-2697(89)90434-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 01/01/2023]
Abstract
A sensitive and comparatively simple method for the assay of diaminopimelate (DAP) decarboxylase, which simultaneously monitors DAP epimerase activity, in the reverse of the biosynthetic direction, is described. The substrate, meso-DAP and products LL-DAP and L-lysine are derivatized with o-phthaldialdehyde and resolved by reversed-phase high-performance liquid chromatography. Separation is achieved on a Spherisorb C18 column using a gradient elution system. This technique offers a high degree of sensitivity as the detection method described can measure picomole quantities of substrate and products.
Collapse
Affiliation(s)
- A N Weir
- Institute for Biotechnological Studies, University of Kent, Canterbury, United Kingdom
| | | | | | | | | |
Collapse
|
18
|
Affiliation(s)
- C Richaud
- Institut de Microbiologie, UA 136, Université Paris-Sud, Orsay, France
| | | |
Collapse
|
19
|
Lam LK, Arnold LD, Kalantar TH, Kelland JG, Lane-Bell PM, Palcic MM, Pickard MA, Vederas JC. Analogs of diaminopimelic acid as inhibitors of meso-diaminopimelate dehydrogenase and LL-diaminopimelate epimerase. J Biol Chem 1988; 263:11814-9. [PMID: 3042781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Analogs 1-8 of diaminopimelic acid (DAP) were synthesized and tested for inhibition of purified meso-DAP D-dehydrogenase from Bacillus sphaericus and of LL-DAP epimerase from Escherichia coli. The dehydrogenase was assayed by monitoring NADPH formation spectrophotometrically at 340 nm. N-Hydroxy DAP 4, N-amino DAP 5, and 4-methylene DAP 6 are substrates of the dehydrogenase with relative rates exceeding those of the meso isomers of the thia analogs 1ab, 2ab, and 3ab. DAP epimerase was assayed by coupling the epimerization of LL-DAP to DL-DAP (Km = 0.26 mM) with the dehydrogenase-catalyzed oxidation of DL-DAP by NADP. Lanthionine isomers 1ab and 1c were stronger inhibitors of the epimerase (Ki = 0.18 mM, Ki' = 0.67 mM, and Ki = 0.42 mM, respectively) than the corresponding meso-sulfoxide 2ab or the meso-sulfone 3ab. Other isomers of 2 and 3, as well as compounds 7 and 8, showed no epimerase inhibition. N-Hydroxy DAP 4 was the most potent competitive inhibitor (Ki = 0.0056 mM) of the epimerase, whereas N-amino DAP 5 is weaker (Ki = 2.9 mM) and 4-methylene DAP 6 is a noncompetitive inhibitor (Ki' = 0.95 mM). Although none of the analogs tested showed time-dependent inactivation of either enzyme, compounds 4, 5, 6, and 7 display substantial antibacterial activities. Possible mechanisms of epimerase inhibition and significance of the DAP pathway as a target for antibiotics are discussed.
Collapse
Affiliation(s)
- L K Lam
- Department of Chemistry, University of Alberta, Edmonton, Canada
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Baumann RJ, Bohme EH, Wiseman JS, Vaal M, Nichols JS. Inhibition of Escherichia coli growth and diaminopimelic acid epimerase by 3-chlorodiaminopimelic acid. Antimicrob Agents Chemother 1988; 32:1119-23. [PMID: 3056252 PMCID: PMC172362 DOI: 10.1128/aac.32.8.1119] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [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: 01/03/2023] Open
Abstract
The diaminopimelic acid (DAP) analog, 3-chloro-DAP, was synthesized and tested as the racemic acid for antibacterial activity and for inhibition of DAP epimerase. 3-Chloro-DAP was a potent inhibitor of DAP epimerase purified from Escherichia coli (Ki = 200 nM), and it is argued that 3-chloro-DAP is converted to a tight-binding transition state analog at the active site of this enzyme. Furthermore, 3-chloro-DAP inhibited growth of two E. coli mutants. In one of the mutants known for supersusceptibility to beta-lactams, inhibition was not seen until the mid-log phase of growth, while in the other mutant, a DAP auxotroph, inhibition occurred much earlier. Growth inhibition was reversed by DAP in both strains. In the auxotroph, the reversal was specific for meso-DAP, indicating that DAP epimerase was the target for 3-chloro-DAP. Thus we suggest a novel mechanism of bacterial growth inhibition which depends on DAP epimerase inhibition by a DAP analog.
Collapse
Affiliation(s)
- R J Baumann
- Merrell Dow Research Institute, Cincinnati, Ohio 45215
| | | | | | | | | |
Collapse
|
21
|
Mengin-Lecreulx D, Michaud C, Richaud C, Blanot D, van Heijenoort J. Incorporation of LL-diaminopimelic acid into peptidoglycan of Escherichia coli mutants lacking diaminopimelate epimerase encoded by dapF. J Bacteriol 1988; 170:2031-9. [PMID: 3283102 PMCID: PMC211082 DOI: 10.1128/jb.170.5.2031-2039.1988] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [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: 01/05/2023] Open
Abstract
Recently a dapF mutant of Escherichia coli lacking the diaminopimelate epimerase was found to have an unusual large LL-diaminopimelic acid (LL-DAP) pool as compared with that of meso-DAP (C. Richaud, W. Higgins, D. Mengin-Lecreulx, and P. Stragier, J. Bacteriol. 169:1454-1459, 1987). In this report, the consequences of high cellular LL-DAP/meso-DAP ratios on the structure and metabolism of peptidoglycan were investigated. For this purpose new efficient high-pressure liquid chromatography techniques for the separation of the DAP isomers were developed. Sacculi from dapF mutants contained a high proportion of LL-DAP that varied greatly with growth conditions. The same was observed with the two DAP-containing precursors, UDP-N-acetylmuramyl-tripeptide and UDP-N-acetylmuramyl-pentapeptide. The limiting steps for the incorporation of LL-DAP into peptidoglycan were found to be its addition to UDP-N-acetylmuramyl-L-alanyl-D-glutamate and the formation of the D-alanyl-DAP cross-bridges. The Km value of the DAP-adding enzyme for LL-DAP was 3.6 x 10(-2) M as compared with 1.1 x 10(-5) M for meso-DAP. When isolated sacculi were treated with Chalaropsis N-acetylmuramidase and the resulting soluble products were analyzed by high-pressure liquid chromatography, the proportion of the main peptidoglycan dimer was lower in the dapF mutant than in the parental strain. Moreover, the proportion of LL-DAP was higher in the main monomer than in the main dimer, where it was almost exclusively located in the donor unit. There are thus very few D-alanyl-LL-DAP cross-bridges, if any. We also observed that large amounts of LL-DAP and N-succinyl-LL-DAP were excreted in the growth medium by the dapF mutant.
Collapse
Affiliation(s)
- D Mengin-Lecreulx
- Unité Associée du Centre National de la Recherche Scientifique, Orsay, France
| | | | | | | | | |
Collapse
|
22
|
Richaud C, Higgins W, Mengin-Lecreulx D, Stragier P. Molecular cloning, characterization, and chromosomal localization of dapF, the Escherichia coli gene for diaminopimelate epimerase. J Bacteriol 1987; 169:1454-9. [PMID: 3031013 PMCID: PMC211967 DOI: 10.1128/jb.169.4.1454-1459.1987] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The Escherichia coli dapF gene was isolated from a cosmid library as a result of screening for clones overproducing diaminopimelate epimerase. Insertional mutagenesis was performed on the cloned dapF gene with a mini-Mu transposon, leading to chloramphenicol resistance. One of these insertions was transferred onto the chromosome by a double-recombination event, allowing us to obtain a dapF mutant. This mutant accumulated large amounts of LL-diaminopimelate, confirming the blockage in the step catalyzed by the dapF product, but did not require meso-diaminopimelate for growth. The dapF gene was localized in the 85-min region of the E. coli chromosome between cya and uvrD.
Collapse
|
23
|
Girodeau JM, Agouridas C, Masson M, Pineau R, Le Goffic F. The lysine pathway as a target for a new genera of synthetic antibacterial antibiotics? J Med Chem 1986; 29:1023-30. [PMID: 3086556 DOI: 10.1021/jm00156a021] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Unsaturated analogues of diaminopimelic acid have been synthesized. The amino acids were designed so that they would be reversible or irreversible inhibitors of both of the two last enzymes of the lysine pathway. The compounds were tested with meso-diaminopimelate decarboxylase. trans-3,4-Didehydrodiaminopimelic acid (2) was found to be the most potent inhibitor. The antibacterial activities did not correlate with enzyme inhibiting activities. 4-Methylenediaminopimelic acid 4 showed strong antibacterial properties. It is suggested that L,L-diaminopimelate epimerase could be the target enzyme.
Collapse
|
24
|
Higuma E. [Age estimation using the racemization of amino acid in human dentin]. Kanagawa Shigaku 1985; 20:320-30. [PMID: 3869655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
25
|
Wiseman JS, Nichols JS. Purification and properties of diaminopimelic acid epimerase from Escherichia coli. J Biol Chem 1984; 259:8907-14. [PMID: 6378903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Diaminopimelic acid epimerase was purified from Escherichia coli. The enzyme is a monomer of Mr = 34,000. Diaminopimelic acid epimerase is not a pyridoxal phosphate-dependent enzyme: there is no evidence for pyridoxal phosphate in the ultraviolet spectrum of the purified enzyme, and the epimerase is not inactivated by carbonyl reagents such as hydroxylamine and sodium borohydride. Exchange of the alpha-protons of the substrates, DL- and LL-diaminopimelic acid, with solvent accompanies epimerization; and exchange of 3H from solvent into diaminopimelic acid gives 3H primarily (80-90%) in the product isomer, regardless of whether the DL- or LL-isomer is substrate. From these results it is concluded that the epimerase utilizes a two-base mechanism for proton translocation. In these major aspects of its mechanism, diaminopimelic acid epimerase resembles proline racemase. It is argued that the relative values of the isotope fractionation factors for the two proton acceptor sites on the enzyme can be estimated from the isotope effects for the DL- and LL-isomers of diaminopimelic acid. The observed difference in the isotope effects predicts that one, but not both, of the proton acceptor sites is a thiol, and it is demonstrated that diaminopimelic acid epimerase has a single thiol which is necessary for activity and which reacts with iodoacetamide.
Collapse
|
26
|
Soda K, Ohshima T, Esaki N. [Use of the stable isotopes in life science (XIII). Applications of isotope effects to enzyme reaction mechanism]. Radioisotopes 1983; 32:42-52. [PMID: 6344152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
27
|
Kanda M, Hori K, Miura S, Yamada Y, Saito Y. A comparative study of essential arginine residues in Gramicidin S synthetase 2 and isoleucyl tRNA synthetase. J Biochem 1982; 92:1951-7. [PMID: 6761339 DOI: 10.1093/oxfordjournals.jbchem.a134126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
In gramicidin S synthetase 2 (GS 2) from Bacillus brevis, L-proline, L-valine, L-ornithine, and L-leucine activations to aminoacyl adenylates are progressively inhibited by phenylglyoxal. The inactivation of GS 2 obeys pseudo-first-order kinetics. ATP completely prevents inactivation of GS 2 by phenylglyoxal, whereas amino acids only partially prevent it. In the presence of ATP, four arginine residues per mol of GS 2 are protected from modification by phenylglyoxal as determined by amino acid analysis and the incorporation of [7-14C]phenylgloxal into the enzyme protein, indicating that a single arginine residue is necessary for each amino acid activation. In isoleucyl tRNA synthetase from Escherichia coli, phenylglyoxal inhibits activation of L-isoleucine to isoleucyl adenylate. ATP completely prevents inactivation, although isoleucine only partially prevents it. One arginine residue of isoleucyl tRNA synthetase is protected by ATP from modification by phenylglyoxal, suggesting that a single arginine residue is essential for isoleucine activation. These results support the involvement of arginine residues in ATP binding with GS 2 or isoleucyl tRNA synthetase, and thus indicate that arginine residues of amino acid activating enzymes are essential for the formation of aminoacyl adenylates in both nonribosomal and ribosomal peptide biosynthesis.
Collapse
|
28
|
Abstract
Thermodynamic racemization may be a cause of aging. Racemases might accelerate the aging process. If enzymatic racemization does accelerate aging, then the use of chemical or immunological inhibitors of racemases might retard aging.
Collapse
|
29
|
Abstract
An enzymic assay for individual isomers (meso-, LL- and DD-) of 2,6-diaminopimelate was developed. The enzyme 2,6-diaminopimelate decarboxylase specifically attacked meso-diaminopimelate and was used to measure this isomer manometrically. The meso- and LL-isomers were measured together manometrically in a coupled assay with diaminopimelate decarboxylase and diaminopimelate epimerase (which converts LL-diaminopimelate into meso-diaminopimelate). The DD-isomer was not attacked by either enzyme and was measured, as residual diaminopimelate after the coupled assay, by a colorimetric method, which was also used to measure total diaminopimelate before enzymic treatments. The coupled enzymes were also used to prepare pure DD-isomer from chemically synthesized diaminopimelate. A mixture of diaminopimelate isomers was present in walls of four strains of Bacillus megaterium [in each about 75% (w/w) meso-, 18% LL- and 7% DD-] and in walls of two strains of Bacillus cereus (about 85% meso-, 8% LL- and 7% DD-). One strain of B. cereus contained at least 95% meso-diaminopimelate, with only traces of LL- and DD-isomers. Peptidoglycan from Escherichia coli was assayed as containing at least 95% meso-isomer. The proportion of isomers in the wall of a strain of B. megaterium remained constant after growth in a variety of different media.
Collapse
|
30
|
|
31
|
|
32
|
|
33
|
Lamont HC, Staudenbauer WL, Strominger JL. Partial purification and characterization of an aspartate racemase from Streptococcus faecalis. J Biol Chem 1972; 247:5103-6. [PMID: 4626916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
|
34
|
|
35
|
ADAMS E, NORTON IL. PURIFICATION AND PROPERTIES OF INDUCIBLE HYDROXYPROLINE 2-EPIMERASE FROM PSEUDOMONAS. J Biol Chem 1964; 239:1525-35. [PMID: 14189888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
|
36
|
|
37
|
STADTMAN TC, ELLIOTT P. Studies on the enzymic reduction of amino acids. II. Purification and properties of D-proline reductase and a proline racemase from Clostridium sticklandii. J Biol Chem 1957; 228:983-97. [PMID: 13475375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023] Open
|