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1.
Bull Environ Contam Toxicol ; 112(4): 63, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38615298

RESUMO

Research on thermal receipts has previously focused on the toxic effects of dermal exposure from the most publicized developers (e.g., bisphenol A (BPA) and bisphenol S (BPS)), while no studies have reported on the other solvent-extractable compounds therein. Diphenyl sulfone (DPS) is a sensitizer added to thermal receipts, but little is known about DPS concentrations in receipts or potential toxicity. Here, we quantified BPA, BPS, and DPS concentrations and tentatively identified the solvent-extractable compounds of thermal receipts collected from three South Dakota (USA) cities during 2016-2017. An immortalized chicken hepatic cell line, cultured as 3D spheroids, was used to screen effects of DPS, BPS, and 17ß estradiol (E2; 0.1-1000 µM) on cell viability and gene expression changes. These chemicals elicited limited cytotoxicity with LC50 values ranging from 113 to 143 µM, and induced dysregulation in genes associated with lipid and bile acid homeostasis. Taken together, this study generated novel information on solvent-extractable chemicals from thermal receipts and toxicity data for DPS.


Assuntos
Compostos Benzidrílicos , Compostos de Bifenilo , Fenóis , Sulfonas , Sulfonas/toxicidade , Compostos Benzidrílicos/toxicidade , Solventes
2.
Microbiol Resour Announc ; 13(4): e0007924, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38393331

RESUMO

Alteromonas macleodii strain OCN004, a marine gammaproteobacterium in the Alteromonadaceae family, has primarily been studied as a non-pathogenic negative control bacterium during laboratory infection trials to test the virulence of bacterial coral pathogens. The draft genome sequence of A. macleodii strain OCN004 is presented here.

3.
Antonie Van Leeuwenhoek ; 117(1): 45, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424217

RESUMO

Strain AA17T was isolated from an apparently healthy fragment of Montipora capitata coral from the reef surrounding Moku o Lo'e in Kane'ohe Bay, O'ahu, Hawai'i, USA, and was taxonomically evaluated using a polyphasic approach. Comparison of a partial 16S rRNA gene sequence found that strain AA17T shared the greatest similarity with Aestuariibacter halophilus JC2043T (96.6%), and phylogenies based on 16S rRNA gene sequences grouped strain AA17T with members of the Aliiglaciecola, Aestuariibacter, Lacimicrobium, Marisediminitalea, Planctobacterium, and Saliniradius genera. To more precisely infer the taxonomy of strain AA17T, a phylogenomic analysis was conducted and indicated that strain AA17T formed a monophyletic clade with A. halophilus JC2043T, divergent from Aestuariibacter salexigens JC2042T and other related genera. As a result of monophyly and multiple genomic metrics of genus demarcation, strain AA17T and A. halophilus JC2043T comprise a distinct genus for which the name Fluctibacter gen. nov. is proposed. Based on a polyphasic characterisation and identifying differences in genomic and taxonomic data, strain AA17T represents a novel species, for which the name Fluctibacter corallii sp. nov. is proposed. The type strain is AA17T (= LMG 32603 T = NCTC 14664T). This work also supports the reclassification of A. halophilus as Fluctibacter halophilus comb. nov., which is the type species of the Fluctibacter genus. Genomic analyses also support the reclassification of Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica.


Assuntos
Alteromonadaceae , Antozoários , Ácidos Graxos , Animais , Ácidos Graxos/análise , Havaí , Baías , RNA Ribossômico 16S/genética , Filogenia , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana
5.
BioTech (Basel) ; 12(3)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37754202

RESUMO

While normal levels of reactive oxygen and nitrogen species (RONS) are required for proper organismal function, increased levels result in oxidative stress. Oxidative stress may be managed via the scavenging activities of antioxidants (e.g., curcumin) and the action of enzymes, including superoxide dismutase (SOD). In this work, the uptake and clearance of dietary curcuminoids (consisting of curcumin, demethoxycurcumin, and bisdemethoxycurcumin) was assessed in Drosophila melanogaster larvae following chronic or acute exposure. High levels of curcuminoid uptake and loss were observed within a few hours and leveled off within eight hours post treatment onset. The addition or removal of curcuminoids from media resulted in corresponding changes in SOD activity, and the involvement of each of the three SOD genes was assessed for their contribution to total SOD activity. Taken together, these data provide insight into the uptake and clearance dynamics of curcuminoids and indicate that, while SOD activity generally increases following curcuminoid treatment, the individual SOD genes appear to contribute differently to this response.

6.
Antonie Van Leeuwenhoek ; 116(2): 129-141, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36287289

RESUMO

Clade-based taxonomy has become a recognised means of classifying members of the family Vibrionaceae. A multilocus sequence analysis (MLSA) approach based on eight housekeeping genes can be used to infer phylogenetic relationships, which then groups species into monophyletic clades. Recent work on the Vibrionaceae clades added newly described species and updated existing relationships; the Nereis clade currently includes Vibrio nereis and Vibrio hepatarius. A publication characterising Vibrio japonicus as a novel species placed it within the Nereis clade, but this strain was not included in a recently published taxonomic update because a genome sequence was not available for phylogenetic assessment. To resolve this discrepancy and assess the taxonomic position of V. japonicus within the updated clades, we sequenced the complete genome of V. japonicus JCM 31412 T and conducted phylogenetic and genomic analyses of this clade. Vibrio japonicus remains within the Nereis clade and phylogenomic, average nucleotide identity (ANI), and average amino acid identity (AAI) analyses confirm this relationship. Additional genomic assessments on all Nereis clade members found gene clusters and inferred functionalities shared among the species. This work represents the first complete genome of a member of the Nereis clade and updates the clade-based taxonomy of the Vibrionaceae family.


Assuntos
Genoma Bacteriano , Vibrio , Análise de Sequência de DNA , Filogenia , DNA Bacteriano/genética , Vibrio/genética , RNA Ribossômico 16S/genética
7.
Arch Microbiol ; 204(12): 717, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36401660

RESUMO

Strain 5675061T was isolated from a deep-sea microbial mat near hydrothermal vents within the Axial Seamount caldera on the Juan de Fuca Ridge (NE Pacific Ocean) and was taxonomically evaluated using a polyphasic approach. Morphological and chemotaxonomic properties are consistent with characteristics of the genus Streptomyces: aerobic Gram-stain-positive filaments that form spores, L,L-diaminopimelic acid in whole-cell hydrolysates, and iso-C16:0 as the major fatty acid. Phylogenetic analysis, genomic, and biochemical comparisons show close evolutionary relatedness to Streptomyces lonarensis NCL716T, S. bohaiensis 11A07T, and S. otsuchiensis OTB305T but genomic relatedness indices identify strain 5675061T as a distinct species. Based on a polyphasic characterization, identifying differences in genomic and taxonomic data, strain 5675061T represents a novel species, for which the name Streptomyces spiramenti sp. nov. is proposed. The type strain is 5675061T (=LMG 31896T = DSM 111793T).


Assuntos
Streptomyces , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases
8.
Antonie Van Leeuwenhoek ; 115(9): 1215-1228, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35920985

RESUMO

Strain OCN044T was isolated from the homogenised tissue and mucus of an apparently healthy Acropora cytherea coral fragment collected from the western reef terrace of Palmyra Atoll in the Northern Line Islands and was taxonomically evaluated with a polyphasic approach. The morphological and chemotaxonomic properties are consistent with characteristics of the genus Vibrio: Gram-stain-negative rods, oxidase- and catalase-positive, and motile by means of a polar flagellum. Strain OCN044T can be differentiated as a novel subspecies based on 21 differences among chemotaxonomic features (e.g., fatty acids percentages for C12:0 and C18:1 ω7c), enzymatic activities (e.g., DNase and cystine arylamidase), and carbon sources utilized (e.g., L-xylose and D-melezitose) from its nearest genetic relative. Phylogenetic analysis and genomic comparisons show close evolutionary relatedness to Vibrio tetraodonis A511T but the overall genomic relatedness indices identify strain OCN044T as a distinct subspecies. Based on a polyphasic characterisation, differences in genomic and taxonomic data, strain OCN044T represents a novel subspecies of V. tetraodonis A511T, for which the name Vibrio tetraodonis subsp. pristinus subsp. nov. is proposed. The type strain is OCN044T (= LMG 31895T = DSM 111778T).


Assuntos
Antozoários , Vibrio , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Microbiology (Reading) ; 168(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35380530

RESUMO

The bacterium Vibrio coralliilyticus has been implicated in mass mortalities of corals and shellfish larvae. However, using corals for manipulative infection experiments can be logistically difficult compared to other model organisms, so we aimed to establish oyster larvae infections as a proxy model. Therefore, this study assessed the virulence of six wild-type V. coralliilyticus strains, and mutants of one strain with deletions of known virulence factors, between Pacific oyster larvae (Crassostrea gigas) and Hawaiian rice coral (Montipora capitata) infection systems. The wild-type strains tested displayed variable virulence in each system, but virulence levels between hosts were not necessarily comparable. Strains RE98 and OCN008 maintained a medium to high level of virulence across hosts and appeared to be more generalist pathogens. Strain H1, in contrast, was avirulent towards coral but displayed a medium level of virulence towards oyster larvae. Interestingly, the BAA-450 type strain had a medium level of virulence towards coral and was the least virulent to oyster larvae. A comparison of known virulence factors determined that the flagellum, motility or chemotaxis, all of which play a significant role in coral infections, were not crucial for oyster infections with strain OCN008. A genomic comparison of the newly sequenced strain H1 with the other strains tested identified 16 genes potentially specific to coral pathogens that were absent in H1. This is both the first comparison of various V. coralliilyticus strains across infection systems and the first investigation of a strain that is non-virulent to coral. Our results indicate that the virulence of V. coralliilyticus strains in coral is not necessarily indicative of virulence in oyster larvae, and that the set of genes tested are not required for virulence in both model systems. This study increases our understanding of the virulence between V. coralliilyticus strains and helps assess their potential threat to marine environments and shellfish industries.


Assuntos
Antozoários , Crassostrea , Vibrio , Animais , Antozoários/microbiologia , Crassostrea/microbiologia , Larva/microbiologia , Vibrio/genética , Virulência/genética
10.
Astrobiology ; 22(2): 197-209, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35100015

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in astrochemical environments and are disbursed into planetary environments via meteorites and extraterrestrial infall where they may interact with mineral phases to produce quinones important for origins of life. In this study, we assessed the potential of the phyllosilicates montmorillonite (MONT) and kaolinite (KAO), and the enhanced Mojave Mars Simulant (MMS) to convert the PAH anthracene (ANTH) to the biologically important 9,10-anthraquinone (ANTHQ). All studied mineral substrates mediate conversion over the temperature range assessed (25-500°C). Apparent rate curves for conversion were sigmoidal for MONT and KAO, but quadratic for MMS. Conversion efficiency maxima for ANTHQ were 3.06% ± 0.42%, 1.15% ± 0.13%, and 0.56% ± 0.039% for MONT, KAO, and MMS, respectively. We hypothesized that differential substrate binding and compound loss account for the apparent conversion kinetics observed. Apparent loss rate curves for ANTH and ANTHQ were exponential for all substrates, suggesting a pathway for wide distribution of both compounds in warmer prebiotic environments. These findings improve upon our previously reported ANTHQ conversion efficiency on MONT and provide support for a plausible scenario in which PAH-mineral interactions could have produced prebiotically relevant quinones in early Earth environments.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Quinonas , Bentonita , Minerais/química , Hidrocarbonetos Policíclicos Aromáticos/química , Quinonas/química
11.
Microbiol Resour Announc ; 10(49): e0107121, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34881986

RESUMO

Planctobacterium marinum strain K7 is a Gram-negative gammaproteobacterium of the Alteromonadaceae family and is the sole type strain in the genus Planctobacterium. Presented here is the draft whole-genome sequence of P. marinum strain K7.

12.
Microbiol Resour Announc ; 10(50): e0109321, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34913711

RESUMO

Aestuariibacter halophilus strain JC2043, a Gram-negative gammaproteobacterium, is often used as a reference organism for assigning taxonomy within the family Alteromonadaceae. Isolates of this species have also been investigated for compound degradation (e.g., phthalates and oil) and biofilm association. Presented here is the draft genome sequence of A. halophilus strain JC2043.

13.
Orig Life Evol Biosph ; 51(3): 185-213, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34279769

RESUMO

How life arose on the primitive Earth is one of the biggest questions in science. Biomolecular emergence scenarios have proliferated in the literature but accounting for the ubiquity of oxidized (+ 5) phosphate (PO43-) in extant biochemistries has been challenging due to the dearth of phosphate and molecular oxygen on the primordial Earth. A compelling body of work suggests that exogenous schreibersite ((Fe,Ni)3P) was delivered to Earth via meteorite impacts during the Heavy Bombardment (ca. 4.1-3.8 Gya) and there converted to reduced P oxyanions (e.g., phosphite (HPO32-) and hypophosphite (H2PO2-)) and phosphonates. Inspired by this idea, we review the relevant literature to deduce a plausible reduced phospholipid analog of modern phosphatidylcholines that could have emerged in a primordial hydrothermal setting. A shallow alkaline lacustrine basin underlain by active hydrothermal fissures and meteoritic schreibersite-, clay-, and metal-enriched sediments is envisioned. The water column is laden with known and putative primordial hydrothermal reagents. Small system dimensions and thermal- and UV-driven evaporation further concentrate chemical precursors. We hypothesize that a reduced phospholipid arises from Fischer-Tropsch-type (FTT) production of a C8 alkanoic acid, which condenses with an organophosphinate (derived from schreibersite corrosion to hypophosphite with subsequent methylation/oxidation), to yield a reduced protophospholipid. This then condenses with an α-amino nitrile (derived from Strecker-type reactions) to form the polar head. Preliminary modeling results indicate that reduced phospholipids do not aggregate rapidly; however, single layer micelles are stable up to aggregates with approximately 100 molecules.


Assuntos
Meteoroides , Fósforo , Planeta Terra , Fosfatos , Fosfolipídeos
14.
J Exp Biol ; 223(Pt 22)2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33037110

RESUMO

Oxidative stress, which occurs from an imbalance of reactive oxygen and nitrogen species (RONS) and both endogenous and exogenous antioxidants, promotes aging and underlies sex-specific differences in longevity and susceptibility to age-related neurodegeneration. Recent evidence suggests that curcumin, a yellow pigment derived from turmeric and shown to exhibit antioxidant properties as a RONS scavenger, influences the regulation of genetic elements in endogenous antioxidant pathways. To investigate the role of curcumin in sex-specific in vivo responses to oxidative stress, Drosophila were reared on media supplemented with 0.25, 2.5 or 25 mmol l-1 curcuminoids (consisting of curcumin, demethoxycurcumin and bisdemethoxycurcumin) and resistance to oxidative stress and neural parameters were assessed. High levels of curcuminoids exhibited two sex-specific effects: protection from hydrogen peroxide as an oxidative stressor and alterations in turning rate in an open field. Taken together, these results suggest that the influence of curcuminoids as antioxidants probably relies on changes in gene expression and that sexual dimorphism exists in the in vivo response to curcuminoids.


Assuntos
Curcumina , Animais , Antioxidantes , Curcumina/farmacologia , Drosophila melanogaster/genética , Feminino , Masculino , Estresse Oxidativo , Espécies Reativas de Oxigênio
15.
Microbiol Resour Announc ; 9(35)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855258

RESUMO

Vibrio ostreicida is a Gram-negative gammaproteobacterium that has been shown to cause disease in bivalve larvae. Presented here is the draft genome of the type strain Vibrio ostreicida strain PP-203, which was isolated from the inner surface of an Ostrea edulis (European flat oyster) spat container with recorded deaths at a hatchery in Galicia, Spain.

16.
Microbiol Resour Announc ; 9(32)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32763929

RESUMO

The draft genome of Streptomyces sp. strain ventii, an environmental isolate recovered from deep-sea hydrothermal vents in the Pacific Ocean, is presented along with the resequenced draft genomes of the type strains Streptomyces bohaiensis 11A07 and Streptomyces lonarensis NCL 716.

17.
Microbiol Resour Announc ; 9(12)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193232

RESUMO

Vibrio sp. strain OCN044 is a Gram-negative gammaproteobacterium found in marine environments. Presented here is the whole-draft genome sequence of nonpathogenic Vibrio sp. strain OCN044, isolated from a healthy Acropora cytherea colony off the western reef terrace of Palmyra Atoll.

18.
ACS Synth Biol ; 9(1): 63-75, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846576

RESUMO

Cyanobacteria are prolific producers of natural products, and genome mining has shown that many orphan biosynthetic gene clusters can be found in sequenced cyanobacterial genomes. New tools and methodologies are required to investigate these biosynthetic gene clusters, and here we present the use of Anabaena sp. strain PCC 7120 as a host for combinatorial biosynthesis of natural products using the indolactam natural products (lyngbyatoxin A, pendolmycin, and teleocidin B-4) as a test case. We were able to successfully produce all three compounds using codon optimized genes from Actinobacteria. We also introduce a new plasmid backbone based on the native Anabaena 7120 plasmid pCC7120ζ and show that production of teleocidin B-4 can be accomplished using a two-plasmid system, which can be introduced by coconjugation.


Assuntos
Alcaloides/biossíntese , Anabaena/genética , Anabaena/metabolismo , Produtos Biológicos/metabolismo , Toxinas de Lyngbya/biossíntese , Engenharia Metabólica/métodos , Proteínas de Bactérias/genética , Códon/genética , Genes Bacterianos , Família Multigênica , Plasmídeos/genética
19.
Molecules ; 24(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781798

RESUMO

An essential dimension of food tasting (i.e., flavor) is olfactory stimulation by volatile organic compounds (VOCs) emitted therefrom. Here, we developed a novel analytical method based on solid-phase microextraction (SPME) sampling in argon-filled gas sampling bags with direct gas chromatography⁻mass spectrometry (GC-MS) determination to profile the volatile constituents of 31 homemade preserves prepared in South Dakota (USA) during the period 1950⁻1953. Volatile profiles varied considerably, but generally decreased in detected compounds, complexity, and intensity over three successive 2-h SPME sampling periods. Volatile profiles were generally predominated by aldehydes, alcohols, esters, ketones, and organic acids, with terpenoids constituting much of the pickled cucumber volatiles. Bisphenol-A (BPA) was also serendipitously detected and then quantified in 29 samples, at levels ranging from 3.4 to 19.2 µg/kg, within the range of levels known to induce endocrine disruption effects. Absence of BPA in two samples was attributed to their lids lacking plastic liners. As the timing of their preparation coincides with the beginning of BPA incorporation into consumer products, these jars may be some of the first BPA-containing products in the USA. To the best of our knowledge, this is the first effort to characterize BPA in and volatile profiles of rare historical foods with SPME.


Assuntos
Compostos Benzidrílicos/química , Análise de Alimentos , Fenóis/química , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/química , Compostos Benzidrílicos/isolamento & purificação , Aromatizantes/química , Alimentos em Conserva/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fenóis/isolamento & purificação , South Dakota , Compostos Orgânicos Voláteis/isolamento & purificação
20.
Curr Protoc Microbiol ; 52(1): e71, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30398694

RESUMO

Anabaena sp. strain PCC 7120 is a multicellular, filamentous, freshwater cyanobacterium that is capable of differentiating specialized heterocyst cells for nitrogen fixation. This unit includes protocols for the growth and maintenance of Anabaena appropriate for a research or teaching laboratory. Controlled induction and assessment of heterocyst development is also covered. © 2018 by John Wiley & Sons, Inc.


Assuntos
Anabaena/crescimento & desenvolvimento , Contagem de Colônia Microbiana/métodos , Criopreservação/métodos , Coloração e Rotulagem/métodos , Anabaena/genética , Anabaena/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Contagem de Colônia Microbiana/instrumentação , Meios de Cultura/metabolismo , Regulação Bacteriana da Expressão Gênica , Fixação de Nitrogênio
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