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1.
Microbiol Resour Announc ; 13(1): e0013023, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38099679

RESUMO

Twelve Bifidobacterium strains were isolated from fecal samples of inflammatory bowel disease patients and matched "household control" individuals. These include the species Bifidobacterium adolescentis, Bifidobacterium animalis, Bifidobacterium breve, Bifidobacterium catenulatum, Bifidobacterium longum, and Bifidobacterium pseudocatenulatum.

2.
Microb Genom ; 9(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37665209

RESUMO

Bacteroides, the prominent bacteria in the human gut, play a crucial role in degrading complex polysaccharides. Their abundance is influenced by phages belonging to the Crassvirales order. Despite identifying over 600 Crassvirales genomes computationally, only few have been successfully isolated. Continued efforts in isolation of more Crassvirales genomes can provide insights into phage-host-evolution and infection mechanisms. We focused on wastewater samples, as potential sources of phages infecting various Bacteroides hosts. Sequencing, assembly, and characterization of isolated phages revealed 14 complete genomes belonging to three novel Crassvirales species infecting Bacteroides cellulosilyticus WH2. These species, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. 'frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11, spanned two families, and three genera, displaying a broad range of virion productions. Upon testing all successfully cultured Crassvirales species and their respective bacterial hosts, we discovered that they do not exhibit co-evolutionary patterns with their bacterial hosts. Furthermore, we observed variations in gene similarity, with greater shared similarity observed within genera. However, despite belonging to different genera, the three novel species shared a unique structural gene that encodes the tail spike protein. When investigating the relationship between this gene and host interaction, we discovered evidence of purifying selection, indicating its functional importance. Moreover, our analysis demonstrated that this tail spike protein binds to the TonB-dependent receptors present on the bacterial host surface. Combining these observations, our findings provide insights into phage-host interactions and present three Crassvirales species as an ideal system for controlled infectivity experiments on one of the most dominant members of the human enteric virome.


Assuntos
Bacteriófagos , Glicoproteína da Espícula de Coronavírus , Humanos , Bactérias , Bacteriófagos/genética , Bacteroides/genética
3.
Viruses ; 15(8)2023 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-37632008

RESUMO

Achromobacter species colonization of Cystic Fibrosis respiratory airways is an increasing concern. Two adult patients with Cystic Fibrosis colonized by Achromobacter xylosoxidans CF418 or Achromobacter ruhlandii CF116 experienced fatal exacerbations. Achromobacter spp. are naturally resistant to several antibiotics. Therefore, phages could be valuable as therapeutics for the control of Achromobacter. In this study, thirteen lytic phages were isolated and characterized at the morphological and genomic levels for potential future use in phage therapy. They are presented here as the Achromobacter Kumeyaay phage collection. Six distinct Achromobacter phage genome clusters were identified based on a comprehensive phylogenetic analysis of the Kumeyaay collection as well as the publicly available Achromobacter phages. The infectivity of all phages in the Kumeyaay collection was tested in 23 Achromobacter clinical isolates; 78% of these isolates were lysed by at least one phage. A cryptic prophage was induced in Achromobacter xylosoxidans CF418 when infected with some of the lytic phages. This prophage genome was characterized and is presented as Achromobacter phage CF418-P1. Prophage induction during lytic phage preparation for therapy interventions require further exploration. Large-scale production of phages and removal of endotoxins using an octanol-based procedure resulted in a phage concentrate of 1 × 109 plaque-forming units per milliliter with an endotoxin concentration of 65 endotoxin units per milliliter, which is below the Food and Drugs Administration recommended maximum threshold for human administration. This study provides a comprehensive framework for the isolation, bioinformatic characterization, and safe production of phages to kill Achromobacter spp. in order to potentially manage Cystic Fibrosis (CF) pulmonary infections.


Assuntos
Achromobacter denitrificans , Achromobacter , Bacteriófagos , Fibrose Cística , Adulto , Humanos , Bacteriófagos/genética , Fibrose Cística/terapia , Filogenia , Achromobacter/genética , Achromobacter denitrificans/genética , Prófagos , Endotoxinas
4.
bioRxiv ; 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36945541

RESUMO

Bacteroides, the prominent bacteria in the human gut, play a crucial role in degrading complex polysaccharides. Their abundance is influenced by phages belonging to the Crassvirales order. Despite identifying over 600 Crassvirales genomes computationally, only few have been successfully isolated. Continued efforts in isolation of more Crassvirales genomes can provide insights into phage-host-evolution and infection mechanisms. We focused on wastewater samples, as potential sources of phages infecting various Bacteroides hosts. Sequencing, assembly, and characterization of isolated phages revealed 14 complete genomes belonging to three novel Crassvirales species infecting Bacteroides cellulosilyticus WH2. These species, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. 'frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11, spanned two families, and three genera, displaying a broad range of virion productions. Upon testing all successfully cultured Crassvirales species and their respective bacterial hosts, we discovered that they do not exhibit co-evolutionary patterns with their bacterial hosts. Furthermore, we observed variations in gene similarity, with greater shared similarity observed within genera. However, despite belonging to different genera, the three novel species shared a unique structural gene that encodes the tail spike protein. When investigating the relationship between this gene and host interaction, we discovered evidence of purifying selection, indicating its functional importance. Moreover, our analysis demonstrated that this tail spike protein binds to the TonB-dependent receptors present on the bacterial host surface. Combining these observations, our findings provide insights into phage-host interactions and present three Crassvirales species as an ideal system for controlled infectivity experiments on one of the most dominant members of the human enteric virome. Impact statement: Bacteriophages play a crucial role in shaping microbial communities within the human gut. Among the most dominant bacteriophages in the human gut microbiome are Crassvirales phages, which infect Bacteroides. Despite being widely distributed, only a few Crassvirales genomes have been isolated, leading to a limited understanding of their biology, ecology, and evolution. This study isolated and characterized three novel Crassvirales genomes belonging to two different families, and three genera, but infecting one bacterial host, Bacteroides cellulosilyticus WH2. Notably, the observation confirmed the phages are not co-evolving with their bacterial hosts, rather have a shared ability to exploit similar features in their bacterial host. Additionally, the identification of a critical viral protein undergoing purifying selection and interacting with the bacterial receptors opens doors to targeted therapies against bacterial infections. Given Bacteroides role in polysaccharide degradation in the human gut, our findings advance our understanding of the phage-host interactions and could have important implications for the development of phage-based therapies. These discoveries may hold implications for improving gut health and metabolism to support overall well-being. Data summary: The genomes used in this research are available on Sequence Read Archive (SRA) within the project, PRJNA737576. Bacteroides cellulosilyticus WH2, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. ' frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11 are all available on GenBank with accessions NZ_CP072251.1 ( B. cellulosilyticus WH2), QQ198717 (Bc01), QQ198718 (Bc03), and QQ198719 (Bc11), and we are working on making the strains available through ATCC. The 3D protein structures for the three Crassvirales genomes are available to download at doi.org/10.25451/flinders.21946034.

5.
Drug Alcohol Depend Rep ; 1: 100006, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36843905

RESUMO

Introduction: Evidence-based treatments for tobacco use are under-utilized and primary care visits may be an opportune time to address this gap. This study examined the rate at which primary care visits included tobacco use treatment and examined patient demographics, smoking characteristics, attitudes about tobacco use treatments, and comorbidities as correlates of treatment provision. Methods: This prospective study assessed demographics, smoking characteristics, attitudes about tobacco use treatments, and comorbidities via interview prior to a primary care visit among 105 patients. One week following the appointment, 85 patients were reassessed for the tobacco use treatments they received during their appointment (i.e., asked about their tobacco use, advised to quit, and provided with a referral to a tobacco use treatment program or an FDA-approved tobacco use medication). Results: 93% of patients were asked about their tobacco use, 74% were advised to quit, 37% were provided with a referral for tobacco use treatment, and 27% received an FDA-approved medication (16% NRT, 11% varenicline or bupropion). Patients with higher quit motivation and who endorsed that medications can reduce cravings were more likely to report receiving tobacco use medication. Patients with a self-reported substance abuse history were less likely to report receiving tobacco use medications. Conclusions: The provision of tobacco use medications within primary care remains low. Strategies to increase patient quit motivation and help patients understand that tobacco use medications can mitigate cravings may increase use. Strategies may also be needed to ensure that patients with comorbid substance abuse still receive tobacco use treatments.

6.
Brain Struct Funct ; 225(3): 1163, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31938933

RESUMO

The author reports that data for electrophysiology findings reported in Figs. 4 and 5 for control group and Meth Rst group have been published previously (Galinato MH et al., J Neurosci. 2018 Feb 21; 38(8):2029-2042.

7.
Biochem Biophys Res Commun ; 503(4): 2690-2697, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30100066

RESUMO

Optineurin (OPTN) mutations are linked to glaucoma pathology and E50K mutation shows massive cell death in photoreceptor cells and retinal ganglion cells. However, little is known about E50K-mediated mitochondrial dysfunction in photoreceptor cell degeneration. We here show that overexpression of E50K expression triggered BDNF deficiency, leading to Bax activation in RGC-5 cells. BDNF deficiency induced mitochondrial dysfunction by decreasing mitochondrial maximal respiration and reducing intracellular ATP level in RGC-5 cells. However, BDNF deficiency did not alter mitochondrial dynamics. Also, BDNF deficiency resulted in LC3-mediated mitophagosome formation in RGC-5 cells. These results strongly suggest that E50K-mediated BDNF deficiency plays a critical role in compromised mitochondrial function in glaucomatous photoreceptor cell degeneration.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Proteínas Associadas aos Microtúbulos/genética , Mitocôndrias/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Fator de Transcrição TFIIIA/genética , Proteína X Associada a bcl-2/genética , Trifosfato de Adenosina/biossíntese , Substituição de Aminoácidos , Animais , Fator Neurotrófico Derivado do Encéfalo/deficiência , Linhagem Celular , Regulação da Expressão Gênica , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/patologia , Mutação , Fosforilação Oxidativa , Fagossomos/metabolismo , Fagossomos/patologia , Células Fotorreceptoras de Vertebrados/patologia , Ratos , Transdução de Sinais , Fator de Transcrição TFIIIA/metabolismo , Proteína X Associada a bcl-2/metabolismo
8.
Brain Struct Funct ; 223(5): 2197-2211, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29441405

RESUMO

Abstinence from unregulated methamphetamine self-administration increases hippocampal dependent, context-driven reinstatement of methamphetamine seeking. The current study tested the hypothesis that alterations in the functional properties of granule cell neurons (GCNs) in the dentate gyrus (DG) of the hippocampus in concert with altered expression of synaptic plasticity-related proteins and ultrastructural changes in the DG are associated with enhanced context-driven methamphetamine-seeking behavior. Whole-cell patch-clamp recordings were performed in acute brain slices from methamphetamine naïve (controls) and methamphetamine experienced animals (during acute withdrawal, during abstinence, after extinction and after reinstatement). Spontaneous excitatory postsynaptic currents (sEPSCs) and intrinsic excitability were recorded from GCNs. Reinstatement of methamphetamine seeking increased sEPSC frequency and produced larger amplitude responses in GCNs compared to controls and all other groups. Reinstatement of methamphetamine seeking reduced spiking capability in GCNs compared to controls, and all other groups, as indicated by reduced intrinsic spiking elicited by increasing current injections, membrane resistance and fast after hyperpolarization. In rats that reinstated methamphetamine seeking, these altered electrophysiological properties of GCNs were associated with enhanced expression of Fos, GluN2A subunits and PSD95 and reduced expression of GABAA subunits in the DG and enhanced expression of synaptic PSD in the molecular layer. The alterations in functional properties of GCNs and plasticity related proteins in the DG paralleled with no changes in structure of microglial cells in the DG. Taken together, our results demonstrate that enhanced reinstatement of methamphetamine seeking results in alterations in intrinsic spiking and spontaneous glutamatergic synaptic transmission in the GCNs and concomitant increases in neuronal activation of GCNs, and expression of GluNs and decreases in GABAA subunits that may contribute to the altered synaptic connectivity-neuronal circuitry-and activity in the hippocampus, and enhance propensity for relapse.


Assuntos
Estimulantes do Sistema Nervoso Central/administração & dosagem , Sinais (Psicologia) , Giro Denteado/efeitos dos fármacos , Comportamento de Procura de Droga/efeitos dos fármacos , Metanfetamina/administração & dosagem , Neurônios/efeitos dos fármacos , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Condicionamento Operante/fisiologia , Giro Denteado/citologia , Giro Denteado/ultraestrutura , Comportamento de Procura de Droga/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Extinção Psicológica , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Masculino , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , Microglia/ultraestrutura , Neurônios/ultraestrutura , Proteínas Oncogênicas v-fos/metabolismo , Ratos , Ratos Wistar , Receptores de GABA-A/metabolismo , Autoadministração
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