Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 345
Filter
Add more filters

Publication year range
1.
Nature ; 571(7763): 72-78, 2019 07.
Article in English | MEDLINE | ID: mdl-31217586

ABSTRACT

New antibiotics are needed to combat rising levels of resistance, with new Mycobacterium tuberculosis (Mtb) drugs having the highest priority. However, conventional whole-cell and biochemical antibiotic screens have failed. Here we develop a strategy termed PROSPECT (primary screening of strains to prioritize expanded chemistry and targets), in which we screen compounds against pools of strains depleted of essential bacterial targets. We engineered strains that target 474 essential Mtb genes and screened pools of 100-150 strains against activity-enriched and unbiased compound libraries, probing more than 8.5 million chemical-genetic interactions. Primary screens identified over tenfold more hits than screening wild-type Mtb alone, with chemical-genetic interactions providing immediate, direct target insights. We identified over 40 compounds that target DNA gyrase, the cell wall, tryptophan, folate biosynthesis and RNA polymerase, as well as inhibitors that target EfpA. Chemical optimization yielded EfpA inhibitors with potent wild-type activity, thus demonstrating the ability of PROSPECT to yield inhibitors against targets that would have eluded conventional drug discovery.


Subject(s)
Antitubercular Agents/classification , Antitubercular Agents/isolation & purification , Drug Discovery/methods , Gene Deletion , Microbial Sensitivity Tests/methods , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Small Molecule Libraries/pharmacology , Antitubercular Agents/pharmacology , DNA Gyrase/metabolism , Drug Resistance, Microbial , Folic Acid/biosynthesis , Molecular Targeted Therapy , Mycobacterium tuberculosis/cytology , Mycobacterium tuberculosis/enzymology , Mycolic Acids/metabolism , Reproducibility of Results , Small Molecule Libraries/classification , Small Molecule Libraries/isolation & purification , Substrate Specificity , Topoisomerase II Inhibitors/isolation & purification , Topoisomerase II Inhibitors/pharmacology , Tryptophan/biosynthesis , Tuberculosis/drug therapy , Tuberculosis/microbiology
2.
Plant Cell ; 33(10): 3367-3385, 2021 10 11.
Article in English | MEDLINE | ID: mdl-34352110

ABSTRACT

Folates are indispensable for plant development, but their molecular mode of action remains elusive. We synthesized a probe, "5-F-THF-Dayne," comprising 5-formyl-tetrahydrofolate (THF) coupled to a photoaffinity tag. Exploiting this probe in an affinity proteomics study in Arabidopsis thaliana, we retrieved 51 hits. Thirty interactions were independently validated with in vitro expressed proteins to bind 5-F-THF with high or low affinity. Interestingly, the interactors reveal associations beyond one-carbon metabolism, covering also connections to nitrogen (N) metabolism, carbohydrate metabolism/photosynthesis, and proteostasis. Two of the interactions, one with the folate biosynthetic enzyme DIHYDROFOLATE REDUCTASE-THYMIDYLATE SYNTHASE 1 (AtDHFR-TS1) and another with N metabolism-associated glutamine synthetase 1;4 (AtGLN1;4), were further characterized. In silico and experimental analyses revealed G35/K36 and E330 as key residues for the binding of 5-F-THF in AtDHFR-TS1 and AtGLN1;4, respectively. Site-directed mutagenesis of AtGLN1;4 E330, which co-localizes with the ATP-binding pocket, abolished 5-F-THF binding as well as AtGLN1;4 activity. Furthermore, 5-F-THF was noted to competitively inhibit the activities of AtDHFR-TS1 and AtGLN1;4. In summary, we demonstrated a regulatory role for 5-F-THF in N metabolism, revealed 5-F-THF-mediated feedback regulation of folate biosynthesis, and identified a total of 14 previously unknown high-affinity binding cellular targets of 5-F-THF. Together, this sets a landmark toward understanding the role of folates in plant development.


Subject(s)
Arabidopsis/metabolism , Carbon/metabolism , Folic Acid/biosynthesis , Leucovorin/metabolism , Nitrogen/metabolism , Proteome/metabolism , Plant Proteins/metabolism
3.
Appl Microbiol Biotechnol ; 108(1): 432, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39102054

ABSTRACT

Infections caused by Staphylococcus aureus pose a significant global public problem. Therefore, new antibiotics and therapeutic strategies are needed to combat this pathogen. This investigation delves into the effects of iclaprim, a newly discovered inhibitor of folic acid synthesis, on S. aureus virulence. The phenotypic and genotypic effects of iclaprim were thoroughly examined in relation to virulence factors, biofilm formation, and dispersal, as well as partial virulence-encoding genes associated with exoproteins, adherence, and regulation in S. aureus MW2, N315, and ATCC 25923. Then, the in vivo effectiveness of iclaprim on S. aureus pathogenicity was explored by a Galleria mellonella larvae infection model. The use of iclaprim at sub-inhibitory concentrations (sub-MICs) resulted in a reduction of α-hemolysin (Hla) production and a differential effect on the activity of coagulase in S. aureus strains. The results of biofilm formation and eradication assay showed that iclaprim was highly effective in depolymerizing the mature biofilm of S. aureus strains at concentrations of 1 MIC or greater, however, inhibited the biofilm-forming ability of only strains N315 and ATCC 25923 at sub-MICs. Interestingly, treatment of strains with sub-MICs of iclaprim resulted in significant stimulation or suppression of most virulence-encoding genes expression. Iclaprim did not affect the production of δ-hemolysin or staphylococcal protein A (SpA), nor did it impact the total activity of proteases, nucleases, and lipases. In vivo testing showed that sub-MICs of iclaprim significantly improves infected larvae survival. The present study offered valuable insights towards a better understating of the influence of iclaprim on different strains of S. aureus. The findings suggest that iclaprim may have potential as an anti-virulence and antibiofilm agent, thus potentially mitigating the pathogenicity of S. aureus and improving clinical outcomes associated with infections caused by this pathogen. KEY POINTS: • Iclaprim effectively inhibits α-hemolysin production and biofilm formation in a strain-dependent manner and was an excellent depolymerizing agent of mature biofilm • Iclaprim affected the mRNA expression of virulence-encoding genes associated with exoproteins, adherence, and regulation • In vivo study in G. mellonella larvae challenged with S. aureus exhibited that iclaprim improves larvae survival.


Subject(s)
Anti-Bacterial Agents , Biofilms , Larva , Microbial Sensitivity Tests , Staphylococcal Infections , Staphylococcus aureus , Virulence Factors , Staphylococcus aureus/drug effects , Staphylococcus aureus/pathogenicity , Staphylococcus aureus/genetics , Biofilms/drug effects , Animals , Virulence Factors/genetics , Anti-Bacterial Agents/pharmacology , Virulence/drug effects , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Larva/microbiology , Moths/microbiology , Hemolysin Proteins/genetics , Folic Acid/pharmacology , Folic Acid/biosynthesis , Folic Acid Antagonists/pharmacology , Coagulase/metabolism , Disease Models, Animal , Pyrimidines
4.
J Sci Food Agric ; 104(12): 7315-7325, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38666511

ABSTRACT

BACKGROUND: Folate is crucial for maintaining health, but humans are unable to synthesize folate and need to obtain it from food. Lactiplantibacillus plantarum can produce the necessary vitamin B for the human body, including folate. Whole genome sequencing technology can clarify the physiological characteristics of folate production in Lactiplantibacillus plantarum. In order to explore new Lactiplantibacillus plantarum that produce folate, the folate production and probiotic characteristics of Lactiplantibacillus plantarum ZFM55 isolated from infant feces were investigated, and whole genome sequencing was performed. RESULTS: The folate synthesis ability of Lactiplantibacillus plantarum ZFM55 were measured, and its total folate production was 299.72 ± 28.81 ng mL-1. Subsequently, its probiotic properties were explored. The antibacterial test showed that its inhibition zone diameter against Staphylococcus aureus and Salmonella typhimurium was 15.5 ± 0.82 mm and 13.88 ± 0.98 mm, respectively. The tolerance test results indicated that it maintained good activity in simulated gastrointestinal tract and bile salt environments. In vitro intestinal simulation experiments had confirmed that Lactiplantibacillus plantarum ZFM55 can increase the abundance of beneficial bacteria such as Bifidobacteria in the intestine and inhibit the growth of harmful bacteria such as Escherichia_Shigella. Genomic sequencing indicated that the genetic material of Lactiplantibacillus plantarum ZFM55 contains one chromosome and three plasmids, and it has 20 genes related to folate synthesis, which explains its ability to produce folate. CONCLUSION: This study reports a new potential probiotic that produces folate, and provides ideas for exploring probiotics with specific probiotic characteristics. © 2024 Society of Chemical Industry.


Subject(s)
Feces , Folic Acid , Probiotics , Probiotics/metabolism , Folic Acid/metabolism , Folic Acid/biosynthesis , Humans , Feces/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/drug effects , Genome, Bacterial , Salmonella typhimurium/genetics , Salmonella typhimurium/metabolism , Salmonella typhimurium/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Genomics , Gastrointestinal Tract/microbiology , Gastrointestinal Tract/metabolism
5.
Mol Cell Proteomics ; 20: 100127, 2021.
Article in English | MEDLINE | ID: mdl-34332122

ABSTRACT

Aging is associated with increased risk of ocular disease, suggesting that age-associated molecular changes in the eye increase its vulnerability to damage. Although there are common pathways involved in aging at an organismal level, different tissues and cell types exhibit specific changes in gene expression with advanced age. Drosophila melanogaster is an established model system for studying aging and neurodegenerative disease that also provides a valuable model for studying age-associated ocular disease. Flies, like humans, exhibit decreased visual function and increased risk of retinal degeneration with age. Here, we profiled the aging proteome and metabolome of the Drosophila eye and compared these data with age-associated transcriptomic changes from both eyes and photoreceptors to identify alterations in pathways that could lead to age-related phenotypes in the eye. Of note, the proteomic and metabolomic changes observed in the aging eye are distinct from those observed in the head or whole fly, suggesting that tissue-specific changes in protein abundance and metabolism occur in the aging fly. Our integration of the proteomic, metabolomic, and transcriptomic data reveals that changes in metabolism, potentially due to decreases in availability of B vitamins, together with chronic activation of the immune response, may underpin many of the events observed in the aging Drosophila eye. We propose that targeting these pathways in the genetically tractable Drosophila system may help to identify potential neuroprotective approaches for neurodegenerative and age-related ocular diseases. Data are available via ProteomeXchange with identifier PXD027090.


Subject(s)
Aging/metabolism , Drosophila Proteins/metabolism , Eye Proteins/metabolism , Eye/metabolism , Folic Acid/biosynthesis , Mitochondria/metabolism , Aging/genetics , Animals , Drosophila Proteins/genetics , Drosophila melanogaster/metabolism , Eye Proteins/genetics , Male , Metabolome , Metabolomics , Proteomics
6.
J Appl Microbiol ; 130(5): 1412-1424, 2021 May.
Article in English | MEDLINE | ID: mdl-32955761

ABSTRACT

Lactic acid bacteria (LAB), widely used as starter cultures for the fermentation of a large variety of food, can improve the safety, shelf life, nutritional value and overall quality of the fermented products. In this regard, the selection of strains delivering health-promoting compounds is now the main objective of many researchers. Although most LAB are auxotrophic for several vitamins, it is known that certain strains have the capability to synthesize B-group vitamins. This is an important property since humans cannot synthesize most vitamins, and these could be obtained by consuming LAB fermented foods. This review discusses the use of LAB as an alternative to fortification by the chemical synthesis to increase riboflavin and folate concentrations in food. Moreover, it provides an overview of the recent applications of vitamin-producing LAB with anti-inflammatory/antioxidant activities against gastrointestinal tract inflammation. This review shows the potential uses of riboflavin and folates producing LAB for the biofortification of food, as therapeutics against intestinal pathologies and to complement anti-inflammatory/anti-neoplastic treatments.


Subject(s)
Folic Acid/biosynthesis , Food, Fortified , Inflammatory Bowel Diseases/therapy , Lactobacillales/metabolism , Mucositis/therapy , Riboflavin/biosynthesis , Animals , Antioxidants/analysis , Fermentation , Fermented Foods , Folic Acid/analysis , Humans , Lactobacillales/isolation & purification , Riboflavin/analysis , Vitamins/analysis , Vitamins/biosynthesis
7.
Genomics ; 112(5): 3142-3149, 2020 09.
Article in English | MEDLINE | ID: mdl-32450257

ABSTRACT

Lactic acid bacteria have been attracting increased attentions recent years because of harboring probiotic properties. In present study, a Lactobacillus pentosus strain ZFM94 was screened from healthy infant feces and its probiotic characteristics were investigated. We found that ZFM94 was resistant to environmental stresses (temperature, pH and NaCl), tolerant to gastrointestinal juice and bile salts, with inhibitory action against pathogens and capacity of folate production etc. Additionally, complete genome sequence of the strain was analyzed to highlight the probiotic features at genetic level. Genomic characteristics along with the experimental studies is critically important for building an appropriate probiotic profile of novel strains. Genes that correspond to phenotypes mentioned above were identified. Moreover, genes potentially related to its adaptation, such as carbon metabolism and carbohydrate transporter, carbohydrate-active enzymes, and a novel gene cluster RaS-RiPPs, were also revealed. Together, ZFM94 could be considered as a potential probiotic candidate.


Subject(s)
Genome, Bacterial , Lactobacillus pentosus/genetics , Probiotics , Anti-Bacterial Agents/metabolism , Bacterial Adhesion , Carbohydrate Metabolism/genetics , Carbon/metabolism , Folic Acid/biosynthesis , Gastric Juice , Genomics , Humans , Infant , Lactobacillus pentosus/enzymology , Lactobacillus pentosus/isolation & purification , Lactobacillus pentosus/metabolism , Membrane Transport Proteins/genetics , Peptides/genetics , Phylogeny , Stress, Physiological
8.
Int J Mol Sci ; 22(4)2021 Feb 09.
Article in English | MEDLINE | ID: mdl-33572433

ABSTRACT

Methotrexate (MTX) is a commonly used antimetabolite, which inhibits folate and DNA synthesis to be effective in the treatment of various malignancies. However, MTX therapy is hindered by the lack of target tumor selectivity. We have designed, synthesized and evaluated a novel glucose-methotrexate conjugate (GLU-MTX) both in vitro and in vivo, in which a cleavable linkage allows intracellular MTX release after selective uptake through glucose transporter-1 (GLUT1). GLU-MTX inhibited the growth of colorectal (DLD-1), breast (MCF-7) and lung (A427) adenocarcinomas, squamous cell carcinoma (SCC-25), osteosarcoma (MG63) cell lines, but not in WI-38 healthy fibroblasts. In tumor cells, GLU-MTX uptake increased 17-fold compared to unconjugated MTX. 4,6-O-ethylidene-α-D-glucose (EDG), a GLUT1 inhibitor, significantly interfered with GLU-MTX induced growth inhibition, suggesting a glucose-mediated drug uptake. Glu-MTX also caused significant tumor growth delay in vivo in breast cancer-bearing mice. These results show that our GLUT-MTX conjugate can be selectively uptake by a range of tumor cells to cause their significant growth inhibition in vitro, which was also confirmed in a breast cancer model in vivo. GLUT1 inhibitor EDG interfered with these effects verifying the selective drug uptake. Accordingly, GLU-MTX offers a considerable tumor selectivity and may offer cancer growth inhibition at reduced toxicity.


Subject(s)
Antimetabolites, Antineoplastic/administration & dosage , Breast Neoplasms/drug therapy , Drug Carriers/chemistry , Glucose/chemistry , Methotrexate/administration & dosage , Animals , Antimetabolites, Antineoplastic/pharmacokinetics , Breast Neoplasms/pathology , Cell Line, Tumor/transplantation , Disease Models, Animal , Drug Liberation/drug effects , Drug Screening Assays, Antitumor , Female , Folic Acid/biosynthesis , Glucose Transporter Type 1/antagonists & inhibitors , Glucose Transporter Type 1/metabolism , Humans , Injections, Intravenous , Methotrexate/pharmacokinetics , Mice
9.
Appl Microbiol Biotechnol ; 104(8): 3331-3337, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32112134

ABSTRACT

Recent studies have shown that inflammatory diseases are becoming more frequent throughout the world. The causes of these disorders are multifactorial and include genetic, immunological, and environmental factors, and intestinal microbiota dysbiosis. The use of beneficial microorganisms has shown to be useful in the prevention and treatment of disorders such as colitis, mucositis, and even colon cancer by their immune-stimulating properties. It has also been shown that certain vitamins, especially riboflavin and folate derivatives, have proven to be helpful in the treatment of these diseases. The application of vitamin-producing lactic acid bacteria, especially strains that produce folate and riboflavin together with immune-stimulating strains, could be used as adjunct treatments in patients suffering from a wide range of inflammatory diseases since they could improve treatment efficiency and prevent undesirable side effects in addition to their nutrition values. In this review, the most up to date information on the current knowledge and uses of vitamin-producing lactic acid bacteria is discussed in order to stimulate further studies in this field.


Subject(s)
Inflammation/therapy , Inflammatory Bowel Diseases/therapy , Lactobacillales/metabolism , Probiotics/therapeutic use , Vitamins/biosynthesis , Animals , Anti-Inflammatory Agents/therapeutic use , Clinical Trials as Topic , Colitis/drug therapy , Folic Acid/biosynthesis , Humans , Inflammation/complications , Inflammatory Bowel Diseases/classification , Riboflavin/biosynthesis , Vitamin K
10.
Genomics ; 111(1): 24-33, 2019 01.
Article in English | MEDLINE | ID: mdl-29277352

ABSTRACT

Lactobacillus mucosae is currently of interest as putative probiotics due to their metabolic capabilities and ability to colonize host mucosal niches. L. mucosae LM1 has been studied in its functions in cell adhesion and pathogen inhibition, etc. It demonstrated unique abilities to use energy from carbohydrate and non-carbohydrate sources. Due to these functions, we report the first complete genome sequence of an L. mucosae strain, L. mucosae LM1. Analysis of the pan-genome in comparison with closely-related Lactobacillus species identified a complete glycogen metabolism pathway, as well as folate biosynthesis, complementing previous proteomic data on the LM1 strain. It also revealed common and unique niche-adaptation genes among the various L. mucosae strains. The aim of this study was to derive genomic information that would reveal the probable mechanisms underlying the probiotic effect of L. mucosae LM1, and provide a better understanding of the nature of L. mucosae sp.


Subject(s)
Adaptation, Physiological , Genome, Bacterial , Lactobacillus/genetics , Lactobacillus/metabolism , Adaptation, Physiological/genetics , Bacterial Adhesion , Ecosystem , Folic Acid/biosynthesis , Genomic Islands , Genomics , Glycogen/metabolism , Glycoside Hydrolases/metabolism , Phylogeny , Probiotics , Proteomics , Whole Genome Sequencing
11.
J Biol Chem ; 293(40): 15725-15732, 2018 10 05.
Article in English | MEDLINE | ID: mdl-30089654

ABSTRACT

Folate derivatives are important cofactors for enzymes in several metabolic processes. Folate-related inhibition and resistance mechanisms in bacteria are potential targets for antimicrobial therapies and therefore a significant focus of current research. Here, we report that the activity of Escherichia coli poly-γ-glutamyl tetrahydrofolate/dihydrofolate synthase (FolC) is regulated by glutamate/glutamine-sensing uridylyltransferase (GlnD), THF-dependent tRNA modification enzyme (MnmE), and UDP-glucose dehydrogenase (Ugd) as shown by direct in vitro protein-protein interactions. Using kinetics analyses, we observed that GlnD, Ugd, and MnmE activate FolC many-fold by decreasing the Khalf of FolC for its substrate l-glutamate. Moreover, FolC inhibited the GTPase activity of MnmE at low GTP concentrations. The growth phenotypes associated with these proteins are discussed. These results, obtained using direct in vitro enzyme assays, reveal unanticipated networks of allosteric regulatory interactions in the folate pathway in E. coli and indicate regulation of polyglutamylated tetrahydrofolate biosynthesis by the availability of nitrogen sources, signaled by the glutamine-sensing GlnD protein.


Subject(s)
Escherichia coli Proteins/chemistry , Escherichia coli/genetics , GTP Phosphohydrolases/chemistry , Gene Expression Regulation, Bacterial , Multienzyme Complexes/chemistry , Nucleotidyltransferases/chemistry , Peptide Synthases/chemistry , Uridine Diphosphate Glucose Dehydrogenase/chemistry , Allosteric Regulation , Binding Sites , Enzyme Assays , Escherichia coli/enzymology , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Folic Acid/biosynthesis , Folic Acid/chemistry , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Glutamic Acid/chemistry , Glutamic Acid/metabolism , Guanosine Triphosphate/chemistry , Guanosine Triphosphate/metabolism , Kinetics , Molecular Docking Simulation , Multienzyme Complexes/genetics , Multienzyme Complexes/metabolism , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism , Peptide Synthases/genetics , Peptide Synthases/metabolism , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Pteroylpolyglutamic Acids/biosynthesis , Pteroylpolyglutamic Acids/chemistry , RNA, Transfer/chemistry , RNA, Transfer/metabolism , Substrate Specificity , Thermodynamics , Uridine Diphosphate Glucose Dehydrogenase/genetics , Uridine Diphosphate Glucose Dehydrogenase/metabolism
12.
Food Microbiol ; 79: 20-26, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30621871

ABSTRACT

Mandatory fortification of foods with folic acid is being questioned by many scientists principally because of the potential adverse secondary effects associated with their excessive consumption. It has been shown that selected strains of lactic acid bacteria (LAB) are able to produce natural forms of folate and these could be included in foods to prevent deficiencies without causing adverse effects. The aim of this study was to evaluate folate production and fol gene expression by Streptococcus gallolyticus subsp. macedonicus (S. macedonicus) CRL415 under different growth conditions in vitro and to assess its potential probiotic application. Results showed that glucose as the principal carbon source, and incubation at 42 °C under controlled pH conditions (6.0) increased folate production, fol gene expression, and growth of S. macedonicus CRL415. This strain was able to produce elevated folate concentrations during milk fermentation without the need of prolonged incubation times and was able to resist conditions simulating the gastrointestinal tract. In addition, S. macedonicus was susceptible to all required antibiotics, and had a good adhesion level to intestinal cells in vitro, making it a promising candidate for biotechnological application as functional starter cultures in the dairy industry.


Subject(s)
Folic Acid/biosynthesis , Probiotics/metabolism , Streptococcus/metabolism , 4-Aminobenzoic Acid/metabolism , Animals , Anti-Bacterial Agents/pharmacology , Bacterial Adhesion , Bile , Caco-2 Cells , Cultured Milk Products/analysis , Cultured Milk Products/microbiology , Folic Acid/genetics , Gastric Juice , Gene Expression Regulation, Bacterial , Glucose/metabolism , Humans , Hydrogen-Ion Concentration , Microbial Sensitivity Tests , Microbial Viability/drug effects , Streptococcus/genetics , Streptococcus/growth & development , Temperature
13.
Ann Hum Genet ; 82(4): 186-199, 2018 07.
Article in English | MEDLINE | ID: mdl-29574679

ABSTRACT

Folate metabolism genes are pivotal to critical biological processes and are related to several conditions, including developmental, cognitive, and cardiovascular anomalies. A systematic catalog of genetic polymorphisms in protein coding regions, regulatory transcription factor binding sites, and miRNA binding sites associated with folate pathway genes may contribute to personalized medicine. We performed a comprehensive computational survey of single nucleotide polymorphisms (SNPs) of folate pathway genes to highlight functional polymorphisms in the coding region, transcription factor binding sites, and miRNAs binding sites. Folate pathway genes were searched through PubMed and Kyoto Encyclopedia of Genes and Genomes pathway databases. SNPs were identified and characterized using the University of California, Santa Cruz genome browser and SNPnexus tool. Functional characterization of nonsynonymous SNPs (nsSNPS) was performed using bioinformatics tools, and common deleterious nsSNPs were identified. We identified 48 genes of folate pathway containing 287 SNPs in the coding regions. Out of these SNPs, rs5742905, rs45511401, and rs1801133 were predicted to be deleterious through four different bioinformatics tools. Three-dimensional structures of two proteins with and without deleterious nsSNPs were predicted by SWISSPDB viewer and SuperPose. Besides, a total of 237 SNPs was identified in transcription factor binding sites using the Genomatix software suite and six miRNA target site SNPs using miRNASNP. This systematic and extensive in silico analysis of functional SNPs of folate pathway may provide a foundation for future targeted mechanistic, structure-function, and genetic epidemiological studies.


Subject(s)
Folic Acid/biosynthesis , MicroRNAs/genetics , Polymorphism, Single Nucleotide , Transcription Factors/genetics , Binding Sites , Computational Biology , Data Mining , Humans , Metabolic Networks and Pathways , Models, Molecular , Protein Structure, Tertiary
14.
J Appl Microbiol ; 125(5): 1494-1501, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29969527

ABSTRACT

AIM: To evaluate two folate-producing strains, Streptococcus (Strep.) thermophilus CRL 808 and Strep. thermophilus CRL 415, against chemically induced mucositis in mice. METHODS AND RESULTS: In vitro assays with Caco-2 cells were performed to evaluate the effect of the bacteria in the presence of 5-fluorouracil (5-FU). For in vivo studies, mice were daily injected with 5-FU to induce intestinal mucositis (IM) and orally administered with folate-producing strains during 6 days. Clinical symptoms, histological parameters and cytokine profiles were assessed. The results showed that Strep. thermophilus CRL 808 increased the cytotoxicity of 5-FU against Caco-2 cells. Administration of this strain in mice with chemically induced IM resulted in a reduction in diarrhoea score and restoration of the intestinal architecture. Cytokine analysis showed that the anti-inflammatory effect by the bacterium is not associated with an immune mechanism. Regarding Strep. thermophilus CRL 415, no improvements were observed in any of the parameters evaluated. CONCLUSION: The administration of the folate-producing Strep. thermophilus CRL 808 has the potential to prevent IM induced by 5-FU in mice. SIGNIFICANCE AND IMPACT OF THE STUDY: Folate-producing LAB could be used in chemotherapy patients to reduce the symptoms of IM, improve their nutritional status and increase the effectiveness of 5-FU.


Subject(s)
Folic Acid/biosynthesis , Lactobacillales/metabolism , Mucositis/therapy , Probiotics/therapeutic use , Animals , Caco-2 Cells , Cytokines/metabolism , Diarrhea/prevention & control , Fluorouracil , Humans , Inflammation/pathology , Intestinal Mucosa/pathology , Intestines/pathology , Lactobacillales/genetics , Mice , Mucositis/chemically induced , Streptococcus thermophilus/genetics , Streptococcus thermophilus/metabolism
15.
Appl Microbiol Biotechnol ; 102(20): 8613-8620, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30073396

ABSTRACT

Folates (vitamin B9) are essential micronutrients which function as cofactors in one-carbon transfer reactions involved in the synthesis of nucleotides and amino acids. Folate deficiency is associated with important diseases such as cancer, anemia, cardiovascular diseases, or neural tube defects. Epidemiological data show that folate deficiency is still highly prevalent in many populations. Hence, food fortification with synthetic folic acid (i.e., folic acid supplementation) has become mandatory in many developed countries. However, folate biofortification of staple crops and dairy products as well as folate bioproduction using metabolically engineered microorganisms are promising alternatives to folic acid supplementation. Here, we review the current strategies aimed at overproducing folates in microorganisms, in view to implement an economic feasible process for the biotechnological production of the vitamin.


Subject(s)
Bacteria/metabolism , Folic Acid/biosynthesis , Industrial Microbiology , Bacteria/genetics , Biofortification , Biosynthetic Pathways , Metabolic Engineering
16.
Food Microbiol ; 69: 116-122, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28941892

ABSTRACT

The ability of folate-producer strains of Streptococcus thermophilus to accumulate folates and the expression of two target genes (folK and folP), involved in the folate biosynthesis, were studied during milk fermentation. An over-expression of folK took place only in the early phase of growth, whereas folP was mainly expressed in the mid log-phase of growth and declined thereafter. The accumulation of total folates, which was quantified by a microbiological assay, was strain-dependent. Two major forms of folates, i.e. tetrahydrofolate (THF) and 5-methyl-tetrahydrofolate (5-Met-THF), were identified and quantified by HPLC. With respect to the level accumulated by a weak folate producer (St 383), used as calibrator in the expression experiments and as control in folate quantification in milk, the strains St 563 and St 399 produced 5-Met-THF in amounts significantly higher than THF. The possibility of using selected folate-producer S. thermophilus strains as functional cultures for a bio-fortification of dairy products is discussed.


Subject(s)
Culture Media/metabolism , Folic Acid/biosynthesis , Streptococcus thermophilus/growth & development , Streptococcus thermophilus/metabolism , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cattle , Chromatography, High Pressure Liquid , Fermentation , Streptococcus thermophilus/isolation & purification
17.
Molecules ; 23(6)2018 Jun 06.
Article in English | MEDLINE | ID: mdl-29882815

ABSTRACT

Antifolates targeting folate biosynthesis within the shikimate-chorismate-folate metabolic pathway are ideal and selective antimicrobials, since higher eukaryotes lack this pathway and rely on an exogenous source of folate. Resistance to the available antifolates, inhibiting the folate pathway, underlines the need for novel antibiotic scaffolds and molecular targets. While para-aminobenzoic acid synthesis within the chorismate pathway constitutes a novel molecular target for antifolates, abyssomicins are its first known natural inhibitors. This review describes the abyssomicin family, a novel spirotetronate polyketide Class I antimicrobial. It summarizes synthetic and biological studies, structural, biosynthetic, and biological properties of the abyssomicin family members. This paper aims to explain their molecular target, mechanism of action, structure⁻activity relationship, and to explore their biological and pharmacological potential. Thirty-two natural abyssomicins and numerous synthetic analogues have been reported. The biological activity of abyssomicins includes their antimicrobial activity against Gram-positive bacteria and mycobacteria, antitumor properties, latent human immunodeficiency virus (HIV) reactivator, anti-HIV and HIV replication inducer properties. Their antimalarial properties have not been explored yet. Future analoging programs using the structure⁻activity relationship data and synthetic approaches may provide a novel abyssomicin structure that is active and devoid of cytotoxicity. Abyssomicin J and atrop-o-benzyl-desmethylabyssomicin C constitute promising candidates for such programs.


Subject(s)
Anti-Infective Agents/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Chorismic Acid/antagonists & inhibitors , Folic Acid/biosynthesis , Anti-Infective Agents/chemistry , Bridged Bicyclo Compounds, Heterocyclic/chemistry , Chorismic Acid/metabolism , Drug Discovery , Molecular Structure
18.
J Am Chem Soc ; 139(37): 13047-13054, 2017 09 20.
Article in English | MEDLINE | ID: mdl-28820585

ABSTRACT

Pterin-containing natural products have diverse functions in life, but an efficient and easy scheme for their in vitro synthesis is not available. Here we report a chemoenzymatic 14-step, one-pot synthesis that can be used to generate 13C- and 15N-labeled dihydrofolates (H2F) from glucose, guanine, and p-aminobenzoyl-l-glutamic acid. This synthesis stands out from previous approaches to produce H2F in that the average yield of each step is >91% and it requires only a single purification step. The use of a one-pot reaction allowed us to overcome potential problems with individual steps during the synthesis. The availability of labeled dihydrofolates allowed the measurement of heavy-atom isotope effects for the reaction catalyzed by the drug target dihydrofolate reductase and established that protonation at N5 of H2F and hydride transfer to C6 occur in a stepwise mechanism. This chemoenzymatic pterin synthesis can be applied to the efficient production of other folates and a range of other natural compounds with applications in nutritional, medical, and cell-biological research.


Subject(s)
Folic Acid/biosynthesis , Isotope Labeling , Tetrahydrofolate Dehydrogenase/metabolism , Carbon Isotopes , Folic Acid/analogs & derivatives , Folic Acid/chemistry , Molecular Structure , Nitrogen Isotopes , Tetrahydrofolate Dehydrogenase/chemistry
19.
Crit Rev Food Sci Nutr ; 57(18): 3894-3910, 2017 Dec 12.
Article in English | MEDLINE | ID: mdl-27351520

ABSTRACT

Folate is an essential micronutrient involved in numerous vital biological reactions. The dietary consumption of naturally occurring vitamin B9 is often inadequate in many countries, and supplementation or fortification programs (using synthetic folic acid) are implemented to alleviate folate deficiency. Other food-based alternatives are possible, such as the use of lactic acid bacteria (LAB) to synthesize folate during fermentation. Many studies have been conducted on this topic, and promising results were reported for some fermented dairy products. However, in other studies, folate consumption by LAB or rather low folate production were observed, resulting in fermented foods that may not significantly contribute to the recommended B9 intake. In addition, the optimum conditions for folate biosynthesis by LAB are still not clear. The aim of this review was thus to (i) clarify the ability of LAB to produce folate in food products, (ii) check if the production of folate by LAB in various fermented foods is sufficient to meet human vitamin B9 requirements and (iii) suggest ways to optimize folate production by LAB in fermented food products.


Subject(s)
Fermentation , Folic Acid Deficiency/prevention & control , Folic Acid/biosynthesis , Lactic Acid/metabolism , Lactobacillus/metabolism , Cultured Milk Products/microbiology , Dietary Supplements , Folic Acid/administration & dosage , Food Microbiology , Functional Food , Humans
20.
Genome ; 60(7): 588-600, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28355497

ABSTRACT

Common beans (Phaseolus vulgaris) are excellent sources of dietary folates, but different varieties contain different amounts of these compounds. Genes coding for dihydroneopterin aldolase (DHNA) and aminodeoxychorismate synthase (ADCS) of the folate synthesis pathway were characterized by PCR amplification, BAC clone sequencing, and whole genome sequencing. All DHNA and ADCS genes in the Mesoamerican cultivar OAC Rex were isolated and compared with those genes in the genome of Andean genotype G19833. Both genotypes have two functional DHNA genes and one pseudo gene. PvDHNA1 and PvDHNA2 proteins have similar secondary structures and conserved residues as DHNA homologs in Staphylococcus aureus and Arabidopsis. Sequence analysis and synteny mapping indicated that PvDHNA1 might be a duplicated and transposed copy of PvDHNA2. There is only one ADCS gene (PvADCS) identified in the bean genome and it is identical in OAC Rex and G19833. PvADCS has the conserved motifs required for catalytic activity similar to other plant ADCS homologs. DHNA and ADCS gene-specific markers were developed, mapped, and compared to their physical locations on chromosomes 1 and 7, respectively. The gene-specific markers developed in this study should be useful for detection and selection of varieties with enhanced folate contents in bean breeding programs.


Subject(s)
Aldehyde-Lyases/genetics , Phaseolus/enzymology , Plant Proteins/genetics , Transaminases/genetics , Aldehyde-Lyases/chemistry , Chromosome Mapping , Folic Acid/biosynthesis , Genotype , Multigene Family , Phaseolus/genetics , Plant Proteins/chemistry , Protein Structure, Secondary , Sequence Analysis, DNA , Signal Transduction , Transaminases/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL