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1.
Biochem Biophys Res Commun ; 673: 36-43, 2023 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-37356143

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a prevalent and aggressive non-Hodgkin's lymphoma, and 40% of patients succumb to death. Despite numerous clinical trials aimed at developing treatment strategies beyond the conventional R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen, there have been no positive results thus far. Although the selective BCL2 inhibitor venetoclax has shown remarkable efficacy in chronic lymphocytic leukemia, its therapeutic effect in DLBCL was limited. We hypothesized that the limited therapeutic effect of venetoclax in DLBCL may be attributed to the complex expression and interactions of BCL2 family members, including BCL2. Therefore, we aimed to comprehensively analyze the expression patterns of BCL2 family members in DLBCL. We analyzed 157 patients with de novo DLBCL diagnosed at Asan Medical Center and Ajou University Hospital. The mRNA expression levels of BCL2 family members were quantified using the NanoString technology. BCL2 family members showed distinct heterogeneous expression patterns both intra- and inter-patient. Using unsupervised hierarchical cluster analysis, we were able to classify patients with similar BCL2 family expression pattern and select groups with clear prognostic features, C1 and C6. In the group with the best prognosis, C1, the expression of pro-apoptotic and pro-apoptotic BH3-only group gene expressions were increased, while anti-apoptotic group expression was significantly increased in both C1 and C6. Based on this, we generated the BCL2 signature score using the expression of pro-apoptotic genes BOK and BCL2L15, and anti-apoptotic gene BCL2. The BCL2 signature score 0 had the best prognosis, score 1/2 had intermediate prognosis, and score 3 had the worst prognosis (EFS, p = 0.0054; OS, p = 0.0011). Multivariate analysis, including COO and IPI, showed that increase in the BCL2 signature score was significantly associated with poor prognosis for EFS, independent of COO and IPI. The BCL2 signature score we proposed in this study provides information on BCL2 family deregulation based on the equilibrium of pro-versus anti-apoptotic BCL2 family, which can aid in the development of new treatment strategies for DLBCL in the future.


Assuntos
Linfoma Difuso de Grandes Células B , Proteínas Proto-Oncogênicas c-bcl-2 , Humanos , Anticorpos Monoclonais Murinos/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Rituximab/uso terapêutico , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Ciclofosfamida/uso terapêutico , Vincristina/uso terapêutico , Prednisona/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
2.
Metab Eng ; 78: 137-147, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37257683

RESUMO

Mycosporine-like amino acids (MAAs) are promising natural sunscreens mainly produced in marine organisms. Until now, metabolic engineering efforts to produce MAAs in heterologous hosts have mainly focused on shinorine production, and the low production levels are still not suitable for industrial applications. In this study, we successfully developed Saccharomyces cerevisiae strains that can efficiently produce various disubstituted MAAs, including shinorine, porphyra-334, and mycosporine-2-glycine (M2G), which are formed by conjugating serine, threonine, and glycine to mycosporine-glycine (MG), respectively. We first generated an MG-producing strain by multiple integration of the biosynthetic genes from cyanobacteria and applying metabolic engineering strategies to increase sedoheptulose-7-phosphate pool, a substrate for MG production. Next, five mysD genes from cyanobacteria, which encode D-Ala-D-Ala ligase homologues that conjugate an amino acid to MG, were introduced into the MG-producing strain to determine the substrate preference of each MysD enzyme. MysDs from Lyngbya sp., Nostoclinckia, and Euhalothece sp. showed high specificity toward serine, threonine, and glycine, resulting in efficient production of shinorine, porphyra-334, and M2G, respectively. This is the first report on the production of porphyra-334 and M2G in S. cerevisiae. Furthermore, we identified that the substrate specificity of MysD was determined by the omega loop region of 43-45 amino acids predicted based on its structural homology to a D-Ala-D-Ala ligase from Thermus thermophilus involved in peptidoglycan biosynthesis. The substrate specificities of two MysD enzymes were interchangeable by swapping the omega loop region. Using the engineered strain expressing mysD from Lyngbya sp. or N. linckia, up to 1.53 g/L shinorine or 1.21 g/L porphyra-334 was produced by fed-batch fermentation in a 5-L bioreactor, the highest titer reported so far. These results suggest that S. cerevisiae is a promising host for industrial production of different types of MAAs, providing a sustainable and eco-friendly alternative for the development of natural sunscreens.


Assuntos
Cianobactérias , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Protetores Solares/química , Protetores Solares/metabolismo , Glicina/metabolismo , Aminoácidos/metabolismo , Cianobactérias/metabolismo , Treonina , Serina/metabolismo
3.
Psychol Med ; 53(12): 5636-5644, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36146953

RESUMO

BACKGROUND: Mood disorders require consistent management of symptoms to prevent recurrences of mood episodes. Circadian rhythm (CR) disruption is a key symptom of mood disorders to be proactively managed to prevent mood episode recurrences. This study aims to predict impending mood episodes recurrences using digital phenotypes related to CR obtained from wearable devices and smartphones. METHODS: The study is a multicenter, nationwide, prospective, observational study with major depressive disorder, bipolar disorder I, and bipolar II disorder. A total of 495 patients were recruited from eight hospitals in South Korea. Patients were followed up for an average of 279.7 days (a total sample of 75 506 days) with wearable devices and smartphones and with clinical interviews conducted every 3 months. Algorithms predicting impending mood episodes were developed with machine learning. Algorithm-predicted mood episodes were then compared to those identified through face-to-face clinical interviews incorporating ecological momentary assessments of daily mood and energy. RESULTS: Two hundred seventy mood episodes recurred in 135 subjects during the follow-up period. The prediction accuracies for impending major depressive episodes, manic episodes, and hypomanic episodes for the next 3 days were 90.1, 92.6, and 93.0%, with the area under the curve values of 0.937, 0.957, and 0.963, respectively. CONCLUSIONS: We predicted the onset of mood episode recurrences exclusively using digital phenotypes. Specifically, phenotypes indicating CR misalignment contributed the most to the prediction of episodes recurrences. Our findings suggest that monitoring of CR using digital devices can be useful in preventing and treating mood disorders.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Humanos , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo Maior/diagnóstico , Depressão , Estudos de Coortes , Estudos Prospectivos , Mania , Fenótipo , Recidiva
4.
Mar Drugs ; 21(3)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36976200

RESUMO

Marinobazzanan (1), a new bazzanane-type sesquiterpenoid, was isolated from a marine-derived fungus belonging to the genus Acremonium. The chemical structure of 1 was elucidated using NMR and mass spectroscopic data, while the relative configurations were established through the analysis of NOESY data. The absolute configurations of 1 were determined by the modified Mosher's method as well as vibrational circular dichroism (VCD) spectra calculation and it was determined as 6R, 7R, 9R, and 10R. It was found that compound 1 was not cytotoxic to human cancer cells, including A549 (lung cancer), AGS (gastric cancer), and Caco-2 (colorectal cancer) below the concentration of 25 µM. However, compound 1 was shown to significantly decrease cancer-cell migration and invasion and soft-agar colony-formation ability at concentrations ranging from 1 to 5 µM by downregulating the expression level of KITENIN and upregulating the expression level of KAI1. Compound 1 suppressed ß-catenin-mediated TOPFLASH activity and its downstream targets in AGS, A549, and Caco-2 and slightly suppressed the Notch signal pathway in three cancer cells. Furthermore, 1 also reduced the number of metastatic nodules in an intraperitoneal xenograft mouse model.


Assuntos
Antineoplásicos , Sesquiterpenos , Humanos , Animais , Camundongos , Células CACO-2 , Transformação Celular Neoplásica , Antineoplásicos/química , Movimento Celular , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Estrutura Molecular
5.
Artigo em Inglês | MEDLINE | ID: mdl-35576239

RESUMO

Strain GY_HT was isolated from an artificial wetland in Okcheon, Chungcheongbuk-do Province, Republic of Korea. Strain GY_HT was closely related to Pseudolabrys taiwanensis CC-BB4T based on 16S rRNA gene sequences (94.7 % similarity) and clustered within the family Nitrobacteraceae. Cells of the isolate were Gram-stain-negative, catalase-negative and oxidase-positive, and colonies were white or pale transparent. A flagellum was observed, and the isolate could respire both aerobically and anaerobically. Growth of GY_ HT was observed in the following conditions: 10-45 °C, pH 5-11 and 0-4 % NaCl. The optimal conditions for growth were 25 °C, pH 6.5-7.5 and 0.5-1.5 % NaCl. The major fatty acids were C19 : 0 cyclo ω8c (35.8 %) and summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c; 27.4 %). The major quinone was found to be ubiquinone-10. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were the major polar lipids. The G+C content of the genome of GY_HT was 63.3 mol%. Based on its phylogenomic, physiological and biochemical attributes, strain GY_HT represents a novel species of a novel genus of the family Nitrobacteraceae. We propose the name as Undibacter mobilis gen. nov., sp. nov. The type strain is GY_HT (=KCTC 62792T=JCM 32856T).


Assuntos
Cloreto de Sódio , Áreas Alagadas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
6.
Proc Natl Acad Sci U S A ; 116(31): 15645-15650, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31311861

RESUMO

Ammonia-oxidizing archaea (AOA) from the phylum Thaumarchaeota are ubiquitous in marine ecosystems and play a prominent role in carbon and nitrogen cycling. Previous studies have suggested that, like all microbes, thaumarchaea are infected by viruses and that viral predation has a profound impact on thaumarchaeal functioning and mortality, thereby regulating global biogeochemical cycles. However, not a single virus capable of infecting thaumarchaea has been reported thus far. Here we describe the isolation and characterization of three Nitrosopumilus spindle-shaped viruses (NSVs) that infect AOA and are distinct from other known marine viruses. Although NSVs have a narrow host range, they efficiently infect autochthonous Nitrosopumilus strains and display high rates of adsorption to their host cells. The NSVs have linear double-stranded DNA genomes of ∼28 kb that do not display appreciable sequence similarity to genomes of other known archaeal or bacterial viruses and could be considered as representatives of a new virus family, the "Thaspiviridae." Upon infection, NSV replication leads to inhibition of AOA growth, accompanied by severe reduction in the rate of ammonia oxidation and nitrite reduction. Nevertheless, unlike in the case of lytic bacteriophages, NSV propagation is not associated with detectable degradation of the host chromosome or a decrease in cell counts. The broad distribution of NSVs in AOA-dominated marine environments suggests that NSV predation might regulate the diversity and dynamics of AOA communities. Collectively, our results shed light on the diversity, evolution, and potential impact of the virosphere associated with ecologically important mesophilic archaea.


Assuntos
Amônia/metabolismo , Organismos Aquáticos , Archaea , Bacteriófagos/fisiologia , DNA Arqueal , Replicação Viral , Organismos Aquáticos/genética , Organismos Aquáticos/metabolismo , Organismos Aquáticos/virologia , Archaea/genética , Archaea/metabolismo , Archaea/virologia , DNA Arqueal/genética , DNA Arqueal/metabolismo
7.
FEMS Yeast Res ; 21(7)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34612490

RESUMO

Mycosporine-like amino acids (MAAs), microbial secondary metabolites with ultraviolet (UV) absorption properties, are promising natural sunscreen materials. Due to the low efficiency of extracting MAAs from natural producers, production in heterologous hosts has recently received attention. Shinorine is a well characterized MAA with strong UV-A absorption property. Previous, we developed Saccharomyces cerevisiae strain producing shinorine by introducing four shinorine biosynthetic genes from cyanobacterium Nostoc punctiforme. Shinorine is produced from sedoheptulose 7-phosphate (S7P), an intermediate in the pentose phosphate pathway. Shinorine production was greatly improved by using xylose as a co-substrate, which can increase the S7P pool. However, due to a limited xylose-utilizing capacity of the engineered strain, glucose was used as a co-substrate to support cell growth. In this study, we further improved shinorine production by attenuating glucose catabolism via glycolysis, which can redirect the carbon flux from glucose to the pentose phosphate pathway favoring shinorine production. Of the strategies we examined to reduce glycolytic flux, deletion of HXK2, encoding hexokinase, was most effective in increasing shinorine production. Furthermore, by additional expression of Ava3858 from Anabaena variabilis, encoding a rate-limiting enzyme 2-demethyl 4-deoxygadusol synthase, 68.4 mg/L of shinorine was produced in an optimized medium containing 14 g/L glucose and 6 g/L xylose, achieving a 2.2-fold increase compared with the previous strain.


Assuntos
Proteínas de Saccharomyces cerevisiae , Xilose , Cicloexilaminas , Glucose , Glicina/análogos & derivados , Hexoquinase/genética , Saccharomyces cerevisiae/genética , Protetores Solares
8.
Arch Microbiol ; 203(7): 3803-3809, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33993373

RESUMO

A Gram-stain-negative, catalase- and oxidase-positive, rod-shaped bacterium, designated as JK6T was isolated from a coastal marine sediment in Jeju Island. Strain JK6T was characterized by polyphasic investigation including genome features. It grew at pH 5.0-9.0 (optimum 7.5), 18-30 °C (optimum 25 °C) and 1.0-7.0% (w/v) NaCl (optimum 2.0%). Strain JK6T utilized D-mannose, D-glucose, L-fucose, propionate and acetate as carbon and energy sources. The sole quinone was ubiquinone-10, and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, and sphingolipid. Strain JK6T was closely related to Parasphingorhabdus flavimaris SW-151T (98.2%), Parasphingorhabdus marina DSM 22363T (97.6%) and Parasphingorhabdus litoris FR1093T (97.6%) based on 16S rRNA gene sequence similarity. Genome length and GC content were 3.29 Mbp and 53.0%, respectively. Digital DNA-DNA relatedness, average nucleotide identity, and average amino acid identity between strain JK6T and P. flavimaris SW-151T were 16.6%, 73.9%, and 77.6%, respectively. These results showed that the strain can be recognized as a novel bacterium named Parasphingorhabdus halotolerans. The type strain of Parasphingorhabdus halotolerans sp. nov. is JK6T (= KCTC 72818T = VTCC 910111T).


Assuntos
Sedimentos Geológicos , Sphingomonadaceae , Adenoma de Células das Ilhotas Pancreáticas , Ácidos Graxos/análise , Sedimentos Geológicos/microbiologia , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Especificidade da Espécie , Sphingomonadaceae/classificação , Sphingomonadaceae/genética
9.
J Nat Prod ; 84(8): 2249-2255, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34387477

RESUMO

Acremonamide (1) was isolated from a marine-derived fungus belonging to the genus Acremonium. The chemical structure of 1 was established using MS, UV, and NMR spectroscopic data analyses. Acremonamide (1) was found to contain N-Me-Phe, N-Me-Ala, Val, Phe, and 2-hydroxyisovaleric acid. The absolute configurations of the four aforementioned amino acids were determined through acid hydrolysis followed by the advanced Marfey's method, whereas the absolute configuration of 2-hydroxyisovaleric acid was determined through GC-MS analysis after formation of the O-pentafluoropropionylated derivative of the (-)-menthyl ester of 2-hydroxyisovaleric acid. As an intrinsic biological activity, acremonamide (1) did not exert cytotoxicity to cancer and noncancer cells and increased the migration and invasion. Based on these activities, the wound healing properties of acremonamide (1) were confirmed in vitro and in vivo.


Assuntos
Acremonium/química , Peptídeos Cíclicos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Organismos Aquáticos/química , Células CACO-2 , Células HaCaT , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Células NIH 3T3 , Peptídeos Cíclicos/isolamento & purificação
10.
Molecules ; 26(8)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924656

RESUMO

Salicornia europaea L. is a halophyte that grows in salt marshes and muddy seashores, which is widely used both as traditional medicine and as an edible vegetable. This salt-tolerant plant is a source of diverse secondary metabolites with several therapeutic properties, including antioxidant, antidiabetic, cytotoxic, anti-inflammatory, and anti-obesity effects. Therefore, this review summarizes the chemical structure and biological activities of secondary metabolites isolated from Salicornia europaea L.


Assuntos
Chenopodiaceae/química , Animais , Humanos , Compostos Fitoquímicos/química , Plantas Tolerantes a Sal/química
11.
J Public Health Manag Pract ; 27(4): 342-351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32496402

RESUMO

CONTEXT: Despite attention to federal and state governments' response to the US opioid crisis, few studies have systematically examined local governments' role in tackling this problem. OBJECTIVES: To determine what opioid policy and programmatic activities local governments are implementing, which activities are more challenging and require a greater latent ability to implement, and what community, environmental, and institutional factors shape such ability. DESIGN: A cross-sectional survey and multistage sampling procedure. SETTING/PARTICIPANTS: Of all 358 county governments in 5 purposively selected states (Colorado, North Carolina, Ohio, Pennsylvania, and Washington) surveyed, 171 counties (response rate = 47.8%) with complete data on self-reported policy and programmatic activities and predictor variables were eligible for analysis. MAIN OUTCOME MEASURES: Nineteen opioid policy and programmatic activities were analyzed individually and combined into a latent implementation ability index using empirical Bayes means estimates. RESULTS: Item response theory and bivariate analysis were applied. Item response theory estimates suggested that having police officers carry naloxone and establishing a task force of community leaders were easier to implement than more challenging activities such as establishing needle exchanges and allowing arrest alternatives for opioid offenses. Covering individuals' treatment costs was predicted to involve the highest ability. County population size (r = 0.34; 95% confidence interval [CI], 0.20-0.47), population density (r = 0.35; 95% CI, 0.21-0.47), and being a Pennsylvania county (r = 0.45; 95% CI, 0.32-0.56) showed the strongest associations with latent implementation ability. CONCLUSIONS: Counties appear engaged in opioid policy and programmatic activity, although some activities are likely more difficult and may require greater ability to implement than others. More sparsely populated counties appear more disadvantaged in implementing activities for tackling the opioid crisis and may need additional assistance to leverage their ability to build a comprehensive policy and programmatic infrastructure.


Assuntos
Governo Local , Epidemia de Opioides , Teorema de Bayes , Estudos Transversais , Humanos , Políticas , Estados Unidos
12.
Int J Syst Evol Microbiol ; 70(10): 5520-5530, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32910751

RESUMO

A Gram-stain-negative, aerobic, non-motile and coccoid methanotroph, strain IM1T, was isolated from hot spring soil. Cells of strain IM1T were catalase-negative, oxidase-positive and displayed a characteristic intracytoplasmic membrane arrangement of type I methanotrophs. The strain possessed genes encoding both membrane-bound and soluble methane monooxygenases and grew only on methane or methanol. The strain was capable of growth at temperatures between 15 and 48 °C (optimum, 30-45 °C) and pH values between pH 4.8 and 8.2 (optimum, pH 6.2-7.0). Based on phylogenetic analysis of 16S rRNA gene and PmoA sequences, strain IM1T was demonstrated to be affiliated to the genus Methylococcus. The 16S rRNA gene sequence of this strain was most closely related to the sequences of an uncultured bacterium clone FD09 (100 %) and a partially described cultured Methylococcus sp. GDS2.4 (99.78 %). The most closely related taxonomically described strains were Methylococcus capsulatus TexasT (97.92 %), Methylococcus capsulatus Bath (97.86 %) and Methyloterricola oryzae 73aT (94.21 %). Strain IM1T shared average nucleotide identity values of 85.93 and 85.62 % with Methylococcus capsulatus strains TexasT and Bath, respectively. The digital DNA-DNA hybridization value with the closest type strain was 29.90 %. The DNA G+C content of strain IM1T was 63.3 mol% and the major cellular fatty acids were C16 : 0 (39.0 %), C16 : 1 ω7c (24.0 %), C16 : 1 ω6c (13.6 %) and C16 : 1 ω5c (12.0 %). The major ubiquinone was methylene-ubiquinone-8. On the basis of phenotypic, genetic and phylogenetic data, strain IM1T represents a novel species of the genus Methylococcus for which the name Methylococcus geothermalis sp. nov. is proposed, with strain IM1T (=JCM 33941T=KCTC 72677T) as the type strain.


Assuntos
Fontes Termais/microbiologia , Methylococcus/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Methylococcus/isolamento & purificação , Hibridização de Ácido Nucleico , Oxigenases/genética , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
13.
Int J Syst Evol Microbiol ; 70(2): 1042-1047, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31999241

RESUMO

Designated strain K5T was isolated from soil on Jeju Island. The bacterium was aerobic, Gram-stain-negative, oxidase-positive, catalase-low activity, motile, short-rod shaped, opaque and formed white colonies that were circular, raised and had entire margins. Strain K5T was able to grow at 15-40 °C, pH 4-9 and at 0-2 % (w/v) NaCl concentration. Phylogenetic analysis based on its 16S rRNA gene sequences indicated that strain K5T is closely related to Ferrovibrio soli A15T (98.9 % sequence similarity), Ferrovibrio denitrificans Sp-1T (98.7 %) and Ferrovibrio xuzhouensis LM-6T (97.4 %). The sole respiratory quinone was determined to be ubiquinone-10. The dominant fatty acids of strain K5T were summed feature 8 (C18 : 1 ω7c / C18 : 1ω6c, 29.8 %), C19 : 0 cyclo ω8c (20.2 %) and C16 : 0 (24.4 %). DNA G+C content was 63.6 % and DNA-DNA relatedness between strain K5T and other three members of the genus Ferrovibrio ranged from 24 to 28 %. The major polar lipids were identified as phosphatidylglycerol, phosphatidylethanolamine and aminolipids. Moreover, polyphasic characterization revealed that strain K5T represents a novel species in the genus Ferrovibrio, for which the name Ferrovibrio terrae sp. nov. is proposed. The type strain is K5T (=KCCM 43295T=LMG 30611T).


Assuntos
Filogenia , Rhodospirillaceae/classificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Ilhas , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Rhodospirillaceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
14.
Int J Syst Evol Microbiol ; 69(9): 2644-2650, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31162019

RESUMO

A facultatively anaerobic and Gram-stain-negative bacterium, strain GY_GT, was isolated from a river (Daedeock-cheon) in Daejeon, Republic of Korea. The isolate was catalase-positive, oxidase-positive and formed yellow colonies. Strain GY_GT was phylogenetically classified as belonging in the genus Sphingorhabdus. Its closely related strains were Sphingorhabdus wooponensis 03SU3-PT (97.1 % similarity), Sphingorhabdus buctiana T5T (96.9 %), Sphingorhabdus contaminans JC216T (96.5 %), Sphingorhabdus rigui 01SU5-PT (96.5 %) and Sphingorhabdus planktonica G1A_585T (96.3 %) based on 16S rRNA gene sequences. The growth conditions for GY_GT were at 10-45 °C (optimum, 25 °C), pH 6-10 (pH 7) and 0-4% NaCl (0.5-1.5 %). Strain GY_GT could utilize turanose, d-fructose-6-phosphate, glucuronamide, α-keto-glutaric acid and acetoacetic acid. The major fatty acids of strain GY_GT were summed features 8 (C18 : 1 ω7c/C18 : 1 ω6c; 40.6 %) and 3 (C16 : 1 ω6c/C16 : 1 ω7c; 24.7 %). The major quinone required for respiration was Q-10. The polar lipids of strain GY_GT were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and sphingolipid. The G+C content of the genome was 57.7 mol%. The average nucleotide identity and average amino acid identity values between strains GY_GT and S. wooponensis were 71.0 and 72.7 %, respectively. Based on phylogenetic and phenotypic attributes, we suggest that strain GY_GT is a novel species in the genus Sphingorhabdus and propose the name Sphingorhabdus pulchriflava. The type strain is GY_GT (=KCTC 62791T=JCM 32855T).


Assuntos
Filogenia , Rios/microbiologia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Sphingomonadaceae/isolamento & purificação , Ubiquinona/análogos & derivados , Ubiquinona/química
15.
Proc Natl Acad Sci U S A ; 113(28): 7888-93, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27339136

RESUMO

Ammonia-oxidizing archaea (AOA), that is, members of the Thaumarchaeota phylum, occur ubiquitously in the environment and are of major significance for global nitrogen cycling. However, controls on cell growth and organic carbon assimilation by AOA are poorly understood. We isolated an ammonia-oxidizing archaeon (designated strain DDS1) from seawater and used this organism to study the physiology of ammonia oxidation. These findings were confirmed using four additional Thaumarchaeota strains from both marine and terrestrial habitats. Ammonia oxidation by strain DDS1 was enhanced in coculture with other bacteria, as well as in artificial seawater media supplemented with α-keto acids (e.g., pyruvate, oxaloacetate). α-Keto acid-enhanced activity of AOA has previously been interpreted as evidence of mixotrophy. However, assays for heterotrophic growth indicated that incorporation of pyruvate into archaeal membrane lipids was negligible. Lipid carbon atoms were, instead, derived from dissolved inorganic carbon, indicating strict autotrophic growth. α-Keto acids spontaneously detoxify H2O2 via a nonenzymatic decarboxylation reaction, suggesting a role of α-keto acids as H2O2 scavengers. Indeed, agents that also scavenge H2O2, such as dimethylthiourea and catalase, replaced the α-keto acid requirement, enhancing growth of strain DDS1. In fact, in the absence of α-keto acids, strain DDS1 and other AOA isolates were shown to endogenously produce H2O2 (up to ∼4.5 µM), which was inhibitory to growth. Genomic analyses indicated catalase genes are largely absent in the AOA. Our results indicate that AOA broadly feature strict autotrophic nutrition and implicate H2O2 as an important factor determining the activity, evolution, and community ecology of AOA ecotypes.


Assuntos
Amônia/metabolismo , Archaea/fisiologia , Peróxido de Hidrogênio/metabolismo , Archaea/isolamento & purificação , Genoma Bacteriano , Nitrificação , Oxirredução , Peroxidase/metabolismo
16.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167373

RESUMO

Clinical studies show a significant association of childhood adversities and FK506-binding protein 5 (FKBP5) polymorphisms on increasing the susceptibility for neuropsychiatric disorders. However, the mechanisms by which early life stress (ELS) influences FKBP5 actions have not been fully elucidated. We hypothesized that interactions between ELS and high FKBP5 induce phenotypic changes that correspond to underlying molecular changes in the brain. To test this, we exposed newborn mice overexpressing human FKBP5 in the forebrain, rTgFKBP5, to ELS using a maternal separation. Two months after ELS, we observed that ELS increased anxiety levels, specifically in mice overexpressing FKBP5, an effect that was more pronounced in females. Biochemically, Protein kinase B (AKT) phosphorylation was reduced in the dorsal hippocampus in rTgFKBP5 mice, which demonstrates that significant molecular changes occur as a result of ELS when FKBP5 levels are altered. Taken together, our results have a significant impact on our understanding mechanisms underlying the gene x environment interaction showing that anxiety and AKT signaling in the hippocampus were affected by the combination of ELS and FKBP5. An increased knowledge of the molecular mechanisms underlying these interactions may help determine if FKBP5 could be an effective target for the treatment of anxiety and other mood-related illnesses.


Assuntos
Transtornos de Ansiedade/etiologia , Transtornos de Ansiedade/metabolismo , Hipocampo/metabolismo , Acontecimentos que Mudam a Vida , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Estresse Psicológico , Proteínas de Ligação a Tacrolimo/metabolismo , Animais , Ansiedade , Transtornos de Ansiedade/diagnóstico , Comportamento Animal , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Genótipo , Hipocampo/fisiopatologia , Humanos , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Fosforilação , Ligação Proteica , Avaliação de Sintomas , Proteínas de Ligação a Tacrolimo/genética
17.
Int J Syst Evol Microbiol ; 68(7): 2258-2264, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29809120

RESUMO

Strain GI5T was isolated from a surface seawater sample collected from Garorim Bay (West Sea, Republic of Korea). The isolated strain was aerobic, Gram-stain-negative, rod-shaped, motile by means of a polar flagellum, negative for catalase and weakly positive for oxidase. The optimum growth pH, salinity and temperature were determined to be pH 7.5-8.0, 3 % NaCl (w/v) and 25 °C, respectively; the growth ranges were pH 6.0-9.0, 1-7 % NaCl (w/v) and 18-40 °C. The results of phylogenetic analysis of 16S rRNA gene sequences indicated that GI5T clustered within the family Alcanivoracaceae, and most closely with Alcanivorax dieseloleiB-5T and Alcanivorax marinusR8-12T (91.9 % and 91.6 % similarity, respectively). The major cellular fatty acids in GI5T were C18 : 1ω7c/C18 : 1ω6c (44.45 %), C16 : 1ω6c/C16 : 1ω7c (14.17 %) and C16 : 0 (10.19 %); this profile was distinct from those of the closely related species. The major respiratory quinone of GI5T was Q-8. The main polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Two putative alkane hydroxylase (alkB) genes were identified in GI5T. The G+C content of the genomic DNA of GI5T was determined to be 51.2 mol%. On the basis of the results of phenotypic, chemotaxonomic and phylogenetic studies, strain GI5T represents a novel species of a novel genus of the family Alcanivoracaceae, for which we propose the name Ketobacter alkanivorans gen. nov., sp. nov.; the type strain is GI5T (=KCTC 52659T=JCM 31835T).


Assuntos
Alcanivoraceae/classificação , Alcanos/metabolismo , Filogenia , Água do Mar/microbiologia , Alcanivoraceae/genética , Alcanivoraceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
18.
Int J Syst Evol Microbiol ; 67(11): 4298-4303, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28126041

RESUMO

Strain Hb3T was isolated from a tidal flat in Jeollabuk-do Gunsan, Republic of Korea. Cells were Gram-stain-negative, oxidase- and catalase-positive, rod-shaped and motile. The strain grew optimally at 25-35 °C, at pH 6.0-6.5 and with 3.0-10.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain Hb3T belonged to the genus Halomonas. Strain Hb3T was related most closely to Halomonas ventosae Al12T (98.6 % 16S rRNA gene sequence similarity), Halomonas denitrificans M29T (98.6 %) and Halomonas saccharevitans AJ275T (98.4 %). Moreover, multilocus sequence analysis using the gyrB, rpoD and secA genes supported the phylogenetic position of strain Hb3T. The genomic G+C content of strain Hb3T was 67.9 mol%. DNA-DNA hybridization values for strain Hb3T versus H. ventosae Al12T, H. denitrificans M29T and H. saccharevitans AJ275T were 38.0, 54.5 and 47.4 %, respectively. The major quinone was ubiquinone Q-9 and the major fatty acids were C18 : 1ω7c, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and C19 : 0 cyclo ω8c. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, amino lipid, six unidentified phospholipids and an unidentified lipid comprised the polar lipid profile. On the basis of the data presented in this report, strain Hb3T represents a novel species of the genus Halomonas. The name Halomonas aestuarii sp. nov. is proposed for this novel species. The type strain is Hb3T (=KCTC 52253T=JCM 31415T).


Assuntos
Sedimentos Geológicos/microbiologia , Halomonas/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Halomonas/genética , Halomonas/isolamento & purificação , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
19.
Int J Syst Evol Microbiol ; 67(11): 4456-4461, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28945530

RESUMO

An extremely halophilic archaeal strain SP28T was isolated from the Gomso solar saltern, Republic of Korea. Cells of the new strain SP28T were pleomorphic and Gram stain negative, and produced red-pigmented colonies. These grew in medium with 2.5-4.5 M NaCl (optimum 3.1 M) and 0.05-0.5 M MgCl2 (optimum 0.1 M), at 25-50 °C (optimum 37 °C) and at a pH of 6.5-8.5 (optimum pH 8.0). Mg2+ was required for growth. A concentration of at least 2 M NaCl was required to prevent cell lysis. Polar lipids included phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one glycolipid chromatographically identical to sulfated mannosyl glucosyl diether. 16S rRNA and rpoB' gene sequence analyses showed that strain SP28T is closely related to Haloplanus ruber R35T (97.3 and 94.1 %, 16S rRNA and rpoB' gene sequence similarity, respectively), Haloplanus litoreus GX21T (97.0 and 92.1 %), Haloplanus salinus YGH66T (96.0 and 91.9 %), Haloplanus vescus RO5-8T (95.9 and 90.9 %), Haloplanus aerogenes TBN37T (95.6 and 90.3 %) and Haloplanus natans RE-101T (95.3 and 89.8 %). The DNA G+C content of the novel strain SP28T was 66.2 mol%, which is slightly higher than that of Hpn.litoreus GX21T (65.8 mol%) and Hpn.ruber R35T (66.0 mol%). DNA-DNA hybridization values betweenHpn.ruber R35T and strain SP28T and between Hpn.litoreus GX21T and strain SP28T were about 24.8 and 20.7 %, respectively. We conclude that strain SP28T represents a novel species of the genus Haloplanus and propose the name Haloplanus salinarum sp. nov. The type strain is SP28T (=JCM 31424T=KCCM 43210T).


Assuntos
Halobacteriaceae/classificação , Filogenia , Salinidade , Microbiologia da Água , Composição de Bases , DNA Arqueal/genética , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , República da Coreia , Análise de Sequência de DNA
20.
Int J Syst Evol Microbiol ; 67(7): 2397-2402, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28708058

RESUMO

A taxonomic study was conducted on strain soj2014T, which was isolated from the surface water of a polynya in the Antarctic Sea. Comparative 16S rRNA gene sequence analysis showed that strain soj2014T belongs to the family Kiloniellaceae and is closely related to Kiloniella spongiae MEBiC09566T, 'Kiloniella litopenaei' P1-1T and Kiloniella laminariae LD81T (98.0 %, 97.8 % and 96.2 % 16S rRNA gene sequence similarity, respectively). The DNA-DNA hybridization values between strain soj2014T and closely related strains were below 28.6 %. The G+C content of the genomic DNA of strain soj2014T was 45.5 mol%. The predominant cellular fatty acids were summed feature 8 (composed of C18 : 1ω6c/C18 : 1ω7c, 57.0 %) and summed feature 3 (composed of C16 : 1ω6c/C16 : 1ω7c, 23.5 %). Strain soj2014T was Gram-stain-negative, slightly curved, spiral-shaped, and motile with a single polar flagellum. The strain grew at 0-30 °C (optimum, 25 °C), in 1.5-5.1 % (w/v) NaCl (optimum, 2.1-2.4 %) and at pH 5.5-9.5 (optimum, 7.5-8.0). It also had differential carbohydrate utilization traits and enzyme activities compared with closely related strains. Based on these phylogenetic, phenotypic and chemotaxonomic analyses, strain soj2014T represents a distinct species, separable from the reference strains, and is, therefore, proposed as a novel species, Kiloniella antarctica sp. nov. The type strain is soj2014T (=KCTC 42186T=JCM 30386T).


Assuntos
Alphaproteobacteria/classificação , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
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