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1.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673874

RESUMO

The trichothecene biosynthesis in Fusarium begins with the cyclization of farnesyl pyrophosphate to trichodiene, followed by subsequent oxygenation to isotrichotriol. This initial bicyclic intermediate is further cyclized to isotrichodermol (ITDmol), a tricyclic precursor with a toxic trichothecene skeleton. Although the first cyclization and subsequent oxygenation are catalyzed by enzymes encoded by Tri5 and Tri4, the second cyclization occurs non-enzymatically. Following ITDmol formation, the enzymes encoded by Tri101, Tri11, Tri3, and Tri1 catalyze 3-O-acetylation, 15-hydroxylation, 15-O-acetylation, and A-ring oxygenation, respectively. In this study, we extensively analyzed the metabolites of the corresponding pathway-blocked mutants of Fusarium graminearum. The disruption of these Tri genes, except Tri3, led to the accumulation of tricyclic trichothecenes as the main products: ITDmol due to Tri101 disruption; a mixture of isotrichodermin (ITD), 7-hydroxyisotrichodermin (7-HIT), and 8-hydroxyisotrichodermin (8-HIT) due to Tri11 disruption; and a mixture of calonectrin and 3-deacetylcalonectrin due to Tri1 disruption. However, the ΔFgtri3 mutant accumulated substantial amounts of bicyclic metabolites, isotrichotriol and trichotriol, in addition to tricyclic 15-deacetylcalonectrin (15-deCAL). The ΔFgtri5ΔFgtri3 double gene disruptant transformed ITD into 7-HIT, 8-HIT, and 15-deCAL. The deletion of FgTri3 and overexpression of Tri6 and Tri10 trichothecene regulatory genes did not result in the accumulation of 15-deCAL in the transgenic strain. Thus, the absence of Tri3p and/or the presence of a small amount of 15-deCAL adversely affected the non-enzymatic second cyclization and C-15 hydroxylation steps.


Assuntos
Fusarium , Tricotecenos , Fusarium/metabolismo , Fusarium/genética , Ciclização , Tricotecenos/metabolismo , Acetilação , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Fosfatos de Poli-Isoprenil/metabolismo , Vias Biossintéticas
2.
Int J Mol Sci ; 25(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38928120

RESUMO

The compound 15-deacetylcalonectrin (15-deCAL) is a common pathway intermediate in the biosynthesis of Fusarium trichothecenes. This tricyclic intermediate is metabolized to calonectrin (CAL) by trichothecene 15-O-acetyltransferase encoded by Tri3. Unlike other trichothecene pathway Tri gene mutants, the Δtri3 mutant produces lower amounts of the knocked-out enzyme's substrate 15-deCAL, and instead, accumulates higher quantities of earlier bicyclic intermediate and shunt metabolites. Furthermore, evolutionary studies suggest that Tri3 may play a role in shaping the chemotypes of trichothecene-producing Fusarium strains. To better understand the functional role of Tri3p in biosynthesis and evolution, we aimed to develop a method to produce 15-deCAL by using transgenic Fusarium graminearum strains derived from a trichothecene overproducer. Unfortunately, introducing mutant Tri3, encoding a catalytically impaired but structurally intact acetylase, did not improve the low 15-deCAL production level of the ΔFgtri3 deletion strain, and the bicyclic products continued to accumulate as the major metabolites of the active-site mutant. These findings are discussed in light of the enzyme responsible for 15-deCAL production in trichothecene biosynthesis machinery. To efficiently produce 15-deCAL, we tested an alternative strategy of using a CAL-overproducing transformant. By feeding a crude CAL extract to a Fusarium commune strain that was isolated in this study and capable of specifically deacetylating C-15 acetyl, 15-deCAL was efficiently recovered. The substrate produced in this manner can be used for kinetic investigations of this enzyme and its possible role in chemotype diversification.


Assuntos
Fusarium , Mutação , Tricotecenos , Fusarium/genética , Fusarium/metabolismo , Tricotecenos/metabolismo , Acetiltransferases/metabolismo , Acetiltransferases/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Vias Biossintéticas/genética
3.
Int J Mol Sci ; 22(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34768859

RESUMO

Fusarium graminearum species complex produces type B trichothecenes oxygenated at C-7. In axenic liquid culture, F. graminearum mainly accumulates one of the three types of trichothecenes, namely 3-acetyldeoxyinvalenol, 15-acetyldeoxyinvalenol, or mixtures of 4,15-diacetylnivalenol/4-acetylnivalenol, depending on each strain's genetic background. The acetyl groups of these trichothecenes are slowly deacetylated to give deoxynivalenol (DON) or nivalenol (NIV) on solid medium culture. Due to the evolution of F. graminearum FgTri1, encoding a cytochrome P450 monooxygenase responsible for hydroxylation at both C-7 and C-8, new derivatives of DON, designated as NX-type trichothecenes, have recently emerged. To assess the risks of emergence of new NX-type trichothecenes, we examined the effects of replacing FgTri1 in the three chemotypes with FgTri1_NX chemotype, which encodes a cytochrome P450 monooxygenase that can only hydroxylate C-7 of trichothecenes. Similar to the transgenic DON chemotypes, the transgenic NIV chemotype strain accumulated NX-type 4-deoxytrichothecenes in axenic liquid culture. C-4 oxygenated trichothecenes were marginal, despite the presence of a functional FgTri13 encoding a C-4 hydroxylase. At present, outcrossing of the currently occurring NX chemotype with NIV chemotype strains of F. graminearum in the natural environment likely will not yield a new strain that produces a C-4 oxygenated NX-type trichothecene.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Fusarium/metabolismo , Tricotecenos/metabolismo , Cultura Axênica , Sistema Enzimático do Citocromo P-450/genética , Proteínas Fúngicas/metabolismo , Fusarium/genética , Organismos Geneticamente Modificados/genética , Tricotecenos/química
4.
Int J Mol Sci ; 22(24)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34948339

RESUMO

The t-type trichothecene producers Fusarium sporotrichioides and Fusarium graminearum protect themselves against their own mycotoxins by acetylating the C-3 hydroxy group with Tri101p acetylase. To understand the mechanism by which they deal with exogenously added d-type trichothecenes, the Δtri5 mutants expressing all but the first trichothecene pathway enzymes were fed with trichodermol (TDmol), trichothecolone (TCC), 8-deoxytrichothecin, and trichothecin. LC-MS/MS and NMR analyses showed that these C-3 unoxygenated trichothecenes were conjugated with glucose at C-4 by α-glucosidic linkage. As t-type trichothecenes are readily incorporated into the biosynthetic pathway following the C-3 acetylation, the mycotoxins were fed to the ΔFgtri5ΔFgtri101 mutant to examine their fate. LC-MS/MS and NMR analyses demonstrated that the mutant conjugated glucose at C-4 of HT-2 toxin (HT-2) by α-glucosidic linkage, while the ΔFgtri5 mutant metabolized HT-2 to 3-acetyl HT-2 toxin and T-2 toxin. The 4-O-glucosylation of exogenously added t-type trichothecenes appears to be a general response of the ΔFgtri5ΔFgtri101 mutant, as nivalenol and its acetylated derivatives appeared to be conjugated with hexose to some extent. The toxicities of 4-O-glucosides of TDmol, TCC, and HT-2 were much weaker than their corresponding aglycons, suggesting that 4-O-glucosylation serves as a phase II xenobiotic metabolism for t-type trichothecene producers.


Assuntos
Fusarium/metabolismo , Glucose/metabolismo , Desintoxicação Metabólica Fase II , Tricotecenos/metabolismo , Acetilação , Cromatografia Líquida , Espectrometria de Massas em Tandem
5.
Int J Syst Evol Microbiol ; 70(12): 6331-6337, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33095133

RESUMO

A mannan-degrading halophilic archaeal strain, MD130-1T, was isolated from a commercial salt sample. Cells were motile, rod-shaped, and stained Gram-negative. Colonies were pink pigmented. Strain MD130-1T was able to grow at 1.5-4.6 M NaCl (optimum, 3.6 M) at pH 6.0-8.0 (optimum, pH 7.0) and at 25-50 °C (optimum, 40 °C). The DNA G+C content was 62.1 mol% (genome). The orthologous 16S rRNA gene sequence showed the highest similarity (99.4 %) to those of Haloarcula japonica JCM 7785T and Haloarcula hispanica JCM 8911T. The values of genome relatedness between strain MD130-1T and Haloarcula species were 84.33-85.96 % in ANIb and 30.4-32.9 % using GGDC formula 2. The polar lipids of strain MD130-1T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and triglycosyl diether-2. Based on the results of phenotypic and phylogenetic analyses, the strain represents a new species of the genus Haloarcula, for which the name Haloarcula mannanilytica sp. nov. is proposed. The type strain is MD130-1T (=JCM 33835T=KCTC 4287T) isolated from commercial salt made in Ishikawa prefecture, Japan.


Assuntos
Haloarcula/classificação , Filogenia , Cloreto de Sódio/análise , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Arqueal/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Galactose/análogos & derivados , Haloarcula/isolamento & purificação , Japão , Mananas/metabolismo , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Biosci Biotechnol Biochem ; 84(6): 1303-1307, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32043422

RESUMO

We identified the biosynthetic gene cluster for lucilactaene, a cell cycle inhibitor from a filamentous fungus Fusarium sp. RK 97-94. The luc1 knockout strain accumulated demethylated analogs, indicating the involvement of Luc1 methyltransferase in lucilactaene biosynthesis. Lucilactaene showed potent antimalarial activity. Our data suggested that methylation and ether ring formation are essential for its potent antimalarial activity.


Assuntos
Antimaláricos/metabolismo , Furanos/metabolismo , Fusarium/genética , Fusarium/metabolismo , Família Multigênica , Pirróis/metabolismo , Antimaláricos/farmacologia , Ciclo Celular/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Furanos/farmacologia , Técnicas de Inativação de Genes , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Microrganismos Geneticamente Modificados , Pirróis/farmacologia
7.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32366059

RESUMO

It is known that silver has microbicidal qualities; even at a low concentration, silver is active against many kinds of bacteria. Silver nanoparticles (AgNPs) have been extensively studied for a wide range of applications. Alternately, the toxicity of silver to human cells is considerably lower than that to bacteria. Recent studies have shown that AgNPs also have antiviral activity. We found that large amounts of hydroxyl radicals-highly reactive molecular species-are generated when AgNPs are irradiated with ultraviolet (UV) radiation with a wavelength of 365 nm, classified as ultraviolet A (UVA). In this study, we used electron spin resonance direct detection to confirm that UV irradiation of AgNPs produced rapid generation of hydroxyl radicals. As hydroxyl radicals are known to degrade bacteria, viruses, and some chemicals, the enhancement of the microbicidal activity of AgNPs by UV radiation could be valuable for the protection of healthcare workers and the prevention of the spread of infectious diseases.


Assuntos
Radical Hidroxila/química , Nanopartículas Metálicas/química , Prata/química , Raios Ultravioleta , Pessoal de Saúde/estatística & dados numéricos , Humanos
8.
Molecules ; 25(19)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019606

RESUMO

Immediately post-production, commercially available bioshell calcium oxide (BiSCaO) water is colorless, transparent, and strongly alkaline (pH 12.8), and is known to possess deodorizing properties and broad microbicidal activity. However, BiSCaO Water may represent a serious safety risk to the living body, given the strong alkalinity. This study aimed to investigate the safety of BiSCaO Water for use as an antiseptic/disinfectant despite concerns regarding its high alkalinity. The change over time in pH of BiSCaO Water was measured during air contact (stirring BiSCaO Water in ambient air). When sprayed on metal, plastic, wood piece, paper, and skin surfaces, the pH of BiSCaO Water decreased rapidly, providing a white powder coating upon drying. Scanning electron microscopy images, energy dispersive X-ray elemental mapping, and X-ray diffractograms showed that the dried powder residues of BiSCaO Water were composed primarily of calcium carbonate. These results suggested that BiSCaO Water is a potent reagent that may overcome the obstacles of being strongly alkaline, making this material appropriate for use in disinfection against pathogenic microbes.


Assuntos
Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/farmacologia , Desinfecção , Óxidos/farmacologia , Pele/microbiologia , Água/farmacologia , Animais , Coloides/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Pós , Ratos Pelados , Pele/efeitos dos fármacos , Espectrometria por Raios X , Suspensões/química , Madeira/química , Difração de Raios X
9.
Molecules ; 25(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630051

RESUMO

Bioshell calcium oxide (BiSCaO) exhibits deodorizing properties and broad microbicidal activity. In this study, we examined possible utility of BiSCaO Water for that purpose. BiSCaO Water was prepared by adding 10 wt% BiSCaO to clean water and gently collecting the supernatant in a bottle. The same volume of clean water was gently poured onto the BiSCaO precipitate and the supernatant was gently collected in a bottle; this process was repeated fifty times. The produced BiSCaO Water contained nanoparticles (about 400-800 nm) composed of smaller nanoparticles (100-200 nm), and was colorless and transparent, with a pH > 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli such as NBRC 3972 and O-157:H7, Pseudomonas aeruginosa, Salmonella, and Staphylococcus aureus within 15 min. We compared BiSCaO Water with the other microbicidal reagents such as ethanol, BiSCaO, BiSCa(OH)2 suspensions, povidone iodine, NaClO, BiSCaO dispersion and colloidal dispersion with respect to deodorization activity and microbicidal efficacy. The results showed that BiSCaO Water was a potent reagent with excellent deodorization and disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).


Assuntos
Bactérias/crescimento & desenvolvimento , Compostos de Cálcio/farmacologia , Óxidos/farmacologia , Vírus/crescimento & desenvolvimento , Água/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Humanos , Vírus/classificação , Vírus/efeitos dos fármacos , Vírus/isolamento & purificação
10.
IUBMB Life ; 71(7): 835-844, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30635953

RESUMO

Genome editing, as exemplified by CRISPR/Cas9, is now recognized as a powerful tool for the engineering of endogenous target genes. It employs only two components, namely, Cas9 in the form of DNA, mRNA, or protein; and guide RNA (gRNA), which is specific to a target gene. When these components are transferred to cells, they create insertion/deletion mutations (indels) within a target gene. Therefore, when fetuses within the uteri of pregnant murine females are exposed to these reagents, fetal cells incorporating them should show mutations in the target gene. To examine a possible genome editing of fetal cells in vivo, we intravenously administered a solution containing plasmid DNA-FuGENE complex to pregnant wild-type female mice [which had been successfully mated with enhanced green fluorescent protein (EGFP)-expressing male transgenic mice] on day 12.5 of gestation. The plasmid DNA induces the expression of gRNA, which was targeted at the EGFP cDNA, and that of the Cas9 gene. All fetuses in the pregnant females should express EGFP systemically, since they are heterozygous (Tg/+) for the transgene. Thus, the delivery of CRISPR system targeted at EGFP in the fetuses will cause a reduced expression of EGFP as a result of the genome editing of EGFP genomic sequence. Of the 24 fetuses isolated from three pregnant females 2 days after gene delivery, 3 were found to have reduced fluorescence in their hearts. Genotyping of the dissected hearts revealed the presence of the transgene construct (Cas9 gene) in all the samples. Furthermore, all the three samples exhibited mutations at the target loci, although normal cells were also present. Thus, transplacental delivery of gene editing components may be a useful tool for developing animal models with heart disorder for heart-related disease research, and gene therapy in congenital heart defects such as hypertrophic cardiomyopathy (HCM). © 2019 IUBMB Life, 9999(9999):1-10, 2019.


Assuntos
Feto/fisiologia , Edição de Genes , Proteínas de Fluorescência Verde/genética , Coração/embriologia , Mutação , Miócitos Cardíacos/fisiologia , RNA Guia de Cinetoplastídeos/genética , Animais , Proteína 9 Associada à CRISPR/administração & dosagem , Proteína 9 Associada à CRISPR/genética , Células Cultivadas , Feminino , Técnicas de Transferência de Genes , Vetores Genéticos , Genoma , Coração/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/citologia , Plasmídeos , RNA Guia de Cinetoplastídeos/administração & dosagem , Transgenes
11.
Int J Mol Sci ; 20(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775372

RESUMO

Transplacental gene delivery (TPGD) is a technique for delivering nucleic acids to fetal tissues via tail-vein injections in pregnant mice. After transplacental transport, administered nucleic acids enter fetal circulation and are distributed among fetal tissues. TPGD was established in 1995 by Tsukamoto et al., and its mechanisms, and potential applications have been further characterized since. Recently, discoveries of sequence specific nucleases, such as zinc-finger nuclease (ZFN), transcription activator-like effector nucleases (TALEN), and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein-9 nuclease (Cas9) (CRISPR/Cas9), have revolutionized genome editing. In 2019, we demonstrated that intravenous injection of plasmid DNA containing CRISPR/Cas9 produced indels in fetal myocardial cells, which are comparatively amenable to transfection with exogenous DNA. In the future, this unique technique will allow manipulation of fetal cell functions in basic studies of fetal gene therapy. In this review, we describe developments of TPGD and discuss their applications to the manipulation of fetal cells.


Assuntos
Sistemas CRISPR-Cas , DNA/administração & dosagem , Feto/metabolismo , Edição de Genes , Marcação de Genes , Terapia Genética , Placenta/metabolismo , Animais , Feminino , Engenharia Genética , Camundongos , Gravidez
12.
Int J Mol Sci ; 20(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344881

RESUMO

Silver is easily available and is known to have microbicidal effect; moreover, it does not impose any adverse effects on the human body. The microbicidal effect is mainly due to silver ions, which have a wide antibacterial spectrum. Furthermore, the development of multidrug-resistant bacteria, as in the case of antibiotics, is less likely. Silver ions bind to halide ions, such as chloride, and precipitate; therefore, when used directly, their microbicidal activity is shortened. To overcome this issue, silver nanoparticles (Ag NPs) have been recently synthesized and frequently used as microbicidal agents that release silver ions from particle surface. Depending on the specific surface area of the nanoparticles, silver ions are released with high efficiency. In addition to their bactericidal activity, small Ag NPs (<10 nm in diameter) affect viruses although the microbicidal effect of silver mass is weak. Because of their characteristics, Ag NPs are useful countermeasures against infectious diseases, which constitute a major issue in the medical field. Thus, medical tools coated with Ag NPs are being developed. This review outlines the synthesis and utilization of Ag NPs in the medical field, focusing on environment-friendly synthesis and the suppression of infections in healthcare workers (HCWs).


Assuntos
Infecções/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Prata/uso terapêutico , Antibacterianos/efeitos adversos , Anti-Infecciosos/efeitos adversos , Cloretos/química , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Pessoal de Saúde , Humanos , Infecções/microbiologia , Íons/química , Nanopartículas Metálicas/química , Prata/química
13.
J Nat Prod ; 81(4): 1041-1044, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29578706

RESUMO

An artificial metabolic route to an unnatural trichothecene was designed by taking advantage of the broad substrate specificities of the T-2 toxin biosynthetic enzymes of Fusarium sporotrichioides. By feeding 7-hydroxyisotrichodermin, a shunt pathway metabolite of F. graminearum, to a trichodiene synthase-deficient mutant of F. sporotrichioides, 7-hydroxy T-2 toxin (1) was obtained as the final metabolite. Such an approach may have future applications in the metabolic engineering of a variety of fungal secondary metabolites. The toxicity of 7-hydroxy T-2 toxin was 10 times lower than that of T-2 toxin in HL-60 cells.


Assuntos
Fusarium/metabolismo , Toxina T-2/metabolismo , Carbono-Carbono Liases/metabolismo , Linhagem Celular Tumoral , Proteínas Fúngicas/metabolismo , Células HL-60 , Humanos , Micotoxinas/metabolismo , Tricotecenos/metabolismo
14.
Int J Mol Sci ; 19(11)2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30400245

RESUMO

Hydrodynamics-based gene delivery (HGD) is an efficient method for transfecting plasmid DNA into hepatocytes in vivo. However, the resulting gene expression is transient, and occurs in a non-tissue specific manner. The piggyBac (PB) transposon system allows chromosomal integration of a transgene in vitro. This study aimed to achieve long-term in vivo expression of a transgene by performing hepatocyte-specific chromosomal integration of the transgene using PB and HGD. Using this approach, we generated a novel mouse model for a hepatic disorder. A distinct signal from the reporter plasmid DNA was discernible in the murine liver approximately two months after the administration of PB transposons carrying a reporter gene. Then, to induce the hepatic disorder, we first administered mice with a PB transposon carrying a CETD unit (loxP-flanked stop cassette, diphtheria toxin-A chain gene, and poly(A) sites), and then with a plasmid expressing the Cre recombinase under the control of a liver-specific promoter. We showed that this system can be used for in situ manipulation and analysis of hepatocyte function in vivo in non-transgenic (Tg) animals.


Assuntos
Elementos de DNA Transponíveis/genética , Terapia Genética , Fígado/metabolismo , Administração Intravenosa , Animais , Galinhas , Técnicas de Transferência de Genes , Hidrodinâmica , Integrases/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos ICR , Especificidade de Órgãos , Recombinação Genética/genética , Soro/metabolismo
15.
Shokuhin Eiseigaku Zasshi ; 59(3): 121-125, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30033988

RESUMO

We have developed a rapid analysis method for determination of histamine using ultra-performance liquid chromatography and fluorescamine derivatization. Histamine was extracted from foods with trichloroacetic acid after homogenization. The supernatant obtained by centrifugation was filtered and derivatized without solid-phase extraction. The mobile phase was 10 mM phosphate-acetonitrile (75 : 25) without ion-pairing. Recovery tests of histamine from fishes, seasoning and fish products gave acceptable recovery (95.8-117.7%). This method should be useful for rapid evaluation of food poisoning outbreaks.


Assuntos
Produtos Pesqueiros/análise , Fluorescamina , Histamina/análise , Animais , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida
16.
Int J Syst Evol Microbiol ; 67(7): 2274-2278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28671534

RESUMO

Two chitin-degrading halophilic archaeal strains, MC-74T and MC-23, were isolated from commercial salt samples. Cells were motile, rod-shaped and stained Gram-negative. Colonies were vermillion-pigmented. Strains MC-74T and MC-23 were able to grow with 1.5-5.1 M NaCl (optimum, 2.6-3.1 M) at pH 6.0-10.0 (optimum, pH 7.0) and at 20-50 °C (optimum, 40 °C). The orthologous 16S rRNA gene sequence similarity between the two strains was 99.8 %, and the closest phylogenetic relative was Salinarchaeum laminariae JCM 17267T with 99.3-99.5 % similarity. The level of DNA-DNA relatedness between the two strains was 93 and 94 % (reciprocally), and those between the two strains and Salinarchaeumlaminariae JCM 17267T were 35-36 % and 38-39 % (reciprocally). The polar lipids of both strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. Glycolipids were not detected. Based on the phenotypic and phylogenetic analyses, the strains represent a novel species of the genus Salinarchaeum, for which the name Salinarchaeum chitinilyticum sp. nov. is proposed. The type strain is MC-74T (=JCM 19597T=KCTC 4262T), isolated from solar salt produced in France. Strain MC-23, isolated from a commercial solar salt sample produced in China, is an additional strain of the species.


Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio/análise , China , Quitina/metabolismo , DNA Arqueal/genética , França , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Neisseriaceae/genética , Hibridização de Ácido Nucleico , Fosfatidilgliceróis/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Environ Microbiol ; 18(11): 3798-3811, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27120196

RESUMO

Fusarium sporotrichioides genes FsTri11, FsTri13, and FsTri1 encode cytochrome P450 monooxygenases (CYPs) responsible for hydroxylations at C-15, C-4, and C-8 of the trichothecene skeleton, respectively. However, the corresponding genes of nivalenol (NIV)-chemotype Fusarium graminearum remain to be functionally elucidated. In this study, we characterized the roles of these CYPs in NIV biosynthesis. Analyses of the metabolites of the F. graminearum Fgtri11- mutant, a disruptant of FgTri11 encoding isotrichodermin (ITD) C-15 hydroxylase, revealed a small amount of NIV-type trichothecenes suggesting that an alternative C-15 hydroxylase partially complemented FgTRI11p. In contrast, the C-7/C-8 hydroxylations depended solely on FgTRI1p, as suggested by the metabolite profiles of the Fgtri11- Fgtri1- double gene disruptant. Disruption of FgTri1 in both the wild-type and Fgtri13- mutant backgrounds revealed that FgTRI13p exhibits marginal activity toward calonectrin (CAL) and that it was the only C-4 hydroxylase. In addition, feeding experiments demonstrated that the C-4 hydroxylation of a 7-hydroxytrichothecene lacking C-8 ketone was extremely limited. The marginal activity of FgTRI13p toward CAL was advantageous for the C-7/C-8 hydroxylation steps in NIV biosynthesis, as transformation of a C-4 oxygenated trichothecene lacking C-7/C-8 modifications into NIV-type trichothecenes was quite inefficient. The significance of hydroxylation steps in the evolution of Fusarium trichothecenes is discussed.


Assuntos
Fusarium/metabolismo , Tricotecenos/biossíntese , Evolução Biológica , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fusarium/química , Fusarium/enzimologia , Fusarium/genética , Hidroxilação , Tricotecenos/química , Tricotecenos/metabolismo
18.
Int J Syst Evol Microbiol ; 66(12): 5314-5319, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27666573

RESUMO

A Gram-stain-negative, rod-pleomorphic, aerobic, halophilic archaeon, strain MK62-1T, was isolated from commercial salt made from seawater in the Philippines. Strain MK62-1T was able to grow at 2.1-4.7 M NaCl (with optimum at 2.1-2.6 M NaCl), pH 6.5-9.5 (optimum, pH 7.0-7.5) and 20-55 °C (optimum, 45-50 °C). Based on the orthologous 16S rRNA gene sequence, the closest relative was Haloparvum sedimenti JCM 30891T with 99.2 % similarity. The RNA polymerase subunit B' gene sequence also showed the highest similarity (97.4 %) to that of Haloparvum sedimenti DYS4T. The DNA G+C content of MK62-1T was 70.1 mol%, while that of Haloparvum sedimenti JCM 30891T was 69.5 mol% by the HPLC method. The levels of DNA-DNA relatedness between MK62-1T and Haloparvum sedimenti JCM 30891T were 60.6 and 60.8 % (reciprocally). The major polar lipids of the isolate were C20C20 archaeol derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. Based on the phenotypic and phylogenetic analyses, it is proposed that the isolate represents species within the genus Haloparvum, for which the name Haloparvum alkalitolerans sp. nov. is proposed. The type strain is MK62-1T (=JCM 30442T =KCTC 4214T).


Assuntos
Halobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Cloreto de Sódio , Álcalis , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Filipinas , Fosfolipídeos/química , RNA Polimerase II/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Int J Syst Evol Microbiol ; 65(8): 2345-2350, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25870255

RESUMO

A Gram-stain-negative, non-motile, pleomorphic rod-shaped, orange-red-pigmented, facultatively aerobic and haloalkaliphilic archaeon, strain MK13-1T, was isolated from commercial rock salt imported from Pakistan. The NaCl, pH and temperature ranges for growth of strain MK13-1T were 3.0-5.2 M NaCl, pH 8.0-11.0 and 15-50 °C, respectively. Optimal growth occurred at 3.2-3.4 M NaCl, pH 9.0-9.5 and 45 °C. Addition of Mg2+ was not required for growth. The major polar lipids of the isolate were C20C20 and C20C25 archaeol derivatives of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Glycolipids were not detected. The DNA G+C content was 64.1 mol%. The 16S rRNA gene sequence of strain MK13-1T was most closely related to those of the species of the genus Halorubrum, Halorubrum luteum CECT 7303T (95.9% similarity), Halorubrum alkaliphilum JCM 12358T (95.3%), Halorubrum kocurii JCM 14978T (95.3%) and Halorubrum lipolyticum JCM 13559T (95.3%). The rpoB' gene sequence of strain MK13-1T had < 90% sequence similarity to those of other members of the genus Halorubrum. Based on the phylogenetic analysis and phenotypic characterization, strain MK13-1T may represent a novel species of the genus Halorubrum, for which the name Halorubrum gandharaense sp. nov. is proposed, with the type strain MK13-1T ( = JCM 17823T = CECT 7963T).


Assuntos
Halorubrum/classificação , Filogenia , Cloreto de Sódio , Composição de Bases , DNA Arqueal/genética , Halorubrum/genética , Halorubrum/isolamento & purificação , Dados de Sequência Molecular , Paquistão , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura
20.
Front Microbiol ; 13: 738742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722286

RESUMO

Human T-cell lymphotropic virus type 1 (HTLV-1) was the first retrovirus identified as the causative agent of human diseases, such as adult T-cell leukemia, HTLV-1-associated myelopathy, and HTLV-1 uveitis (HU). HU is one of the most frequent ocular inflammatory diseases in endemic areas, which has raised considerable public health concerns. Approximately 30% of HU patients develop secondary glaucoma, which is higher than the general uveitis incidence. We therefore investigated the mechanism underlying the high incidence of glaucoma secondary to HU in vitro. After contact with HTLV-1-producing T cells (MT-2), human trabecular meshwork cells (HTMCs) were infected. The infected cells increased in number, and nuclear factor (NF)-κB expression was activated. Contact between MT-2 cells and HTMCs resulted in significantly upregulated production of inflammatory cytokines, such as IL-6, and chemokines, such as CXCL10, CCL2, and CXCL-8. These findings indicate that the mechanism underlying secondary glaucoma in HU may involve proliferation of trabecular meshwork tissue after contact with HTLV-1-infected cells, resulting in decreased aqueous humor outflow. Upregulated production of inflammatory cytokines and chemokines simultaneously disrupts the normal trabecular meshwork function. This mechanism presumably leads to increased intraocular pressure, eventually resulting in secondary glaucoma.

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