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1.
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
2.
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.

3.
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
4.
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
5.
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.

6.
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
7.
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.

8.
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.

9.
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.

10.
Amino Acids ; 43(1): 195-206, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21922267

RESUMO

Arginine (Arg) has been used for recognizing negatively charged biological molecules, cell penetration, and oligosaccharide mass signal enhancement. The versatility of Arg has inspired the need to develop Arg analogs and to research the structural effects of incorporating Arg analogs. Accordingly, we investigated the effect of Arg side chain length on helix formation by studying 12 Ala-based peptides containing the Arg analogs (S)-2-amino-6-guanidino-hexanoic acid (Agh), (S)-2-amino-4-guanidinobutyric acid (Agb), and (S)-2-amino-3-guanidinopropionic acid (Agp). Solid phase guanidinylation with orthogonal protection strategies was necessary to synthesize Agb- and Agp-containing peptides using Fmoc-based chemistry. The fraction helix for the peptides was determined by circular dichroism spectroscopy, and used to derive the statistical mechanical parameters and energetics for N-capping, C-capping, and helix propagation (propensity). All four Arg analogs were unfavorable for N-capping. The C-cap parameter followed the trend AgpAgh, highlighting the uniqueness of the Arg side chain length in helix formation. Molecular mechanics calculations and a survey on protein structures were consistent with the experimental results. Furthermore, calculations and survey both showed that the g- conformation for the χ1 dihedral was present for the first two residues at the N-terminus of helices, but not favored in the center or C-terminus of helices due to sterics. These results should serve as the foundation for developing Arg-related bioactive compounds and technologies.


Assuntos
Arginina/análogos & derivados , Arginina/química , Peptídeos/síntese química , Conformação Proteica , Sequência de Aminoácidos , Arginina/metabolismo , Dicroísmo Circular , Modelos Moleculares , Estrutura Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Espectrometria de Massas por Ionização por Electrospray
11.
Biochemistry ; 49(43): 9372-84, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-20925317

RESUMO

Helix-coil equilibrium studies are important for understanding helix formation in protein folding, and for helical foldamer design. The quantitative description of a helix using statistical mechanical models is based on experimentally derived helix propensities and the assumption that helix propensity is position-independent. To investigate this assumption, we studied a series of 19-residue Ala-based peptides, to measure the helix propensity for Leu, Phe, and Pff at positions 6, 11, and 16. Circular dichroism spectroscopy revealed that substituting Ala with a given amino acid (Leu, Phe, or Pff) resulted in the following fraction helix trend: KXaa16 > KXaa6 > KXaa11. Helix propensities for Leu, Phe, and Pff at the different positions were derived from the CD data. For the same amino acid, helix propensities were similar at positions 6 and 11, but much higher at position 16 (close to the C-terminus). A survey of protein helices revealed that Leu/Phe-Lys (i, i + 3) sequence patterns frequently occur in two structural patterns involving the helix C-terminus; however, these cases include a left-handed conformation residue. Furthermore, no Leu/Phe-Lys interaction was found except for the Lys-Phe cation-π interaction in two cases of Phe-Ala-Ala-Lys. The apparent high helix propensity at position 16 may be due to helix capping, adoption of a 310-helix near the C-terminus perhaps with Xaa-Lys (i, i + 3) interactions, or proximity to the peptide chain terminus. Accordingly, helix propensity is generally position-independent except in the presence of alternative structures or in the proximity of either chain terminus. These results should facilitate the design of helical peptides, proteins, and foldamers.


Assuntos
Alanina , Peptídeos/química , Substituição de Aminoácidos , Aminoácidos , Dicroísmo Circular , Desenho de Fármacos , Estrutura Secundária de Proteína
12.
Methods Mol Biol ; 340: 95-109, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16957334

RESUMO

beta-Peptides have been used as a platform for developing bioactive compounds with various types of bioactivity such as antimicrobial activity, cholesterol absorption inhibition, somatostatin receptor agonist, and hDM2 inhibition. These bioactive beta-peptides have been designed based on bioactive alpha-peptides. Three main strategies have been used to design bioactive beta-peptides: direct conversion of alpha-peptide sequences into beta-peptide sequences, placement of side chains to provide desirable distribution of physicochemical properties, and the grafting of proteinaceous side chains critical for bioactivity onto beta-peptide structures. This chapter briefly discusses the various strategies employed to design bioactive beta-peptides, followed by protocols for the synthesis of N-alpha-fluorenylmethyloxycarbonyl (Fmoc)-protected beta3-amino acids from Fmoc-protected alpha-amino acids, and synthesis of beta-peptides by solid phase methods using Fmoc-based chemistry.


Assuntos
Aminoácidos/química , Aminoácidos/síntese química , Fluorenos/química , Fluorenos/síntese química , Peptídeos/química , Engenharia de Proteínas , Estrutura Secundária de Proteína , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Humanos , Peptídeos/síntese química , Engenharia de Proteínas/métodos , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Receptores da Somatotropina/antagonistas & inibidores
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