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1.
BMC Biol ; 22(1): 105, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702628

RESUMO

BACKGROUND: Histone H3K4 tri-methylation (H3K4me3) catalyzed by Set1/COMPASS, is a prominent epigenetic mark found in promoter-proximal regions of actively transcribed genes. H3K4me3 relies on prior monoubiquitination at the histone H2B (H2Bub) by Rad6 and Bre1. Swd2/Cps35, a Set1/COMPASS component, has been proposed as a key player in facilitating H2Bub-dependent H3K4me3. However, a more comprehensive investigation regarding the relationship among Rad6, Swd2, and Set1 is required to further understand the mechanisms and functions of the H3K4 methylation. RESULTS: We investigated the genome-wide occupancy patterns of Rad6, Swd2, and Set1 under various genetic conditions, aiming to clarify the roles of Set1 and Rad6 for occupancy of Swd2. Swd2 peaks appear on both the 5' region and 3' region of genes, which are overlapped with its tightly bound two complexes, Set1 and cleavage and polyadenylation factor (CPF), respectively. In the absence of Rad6/H2Bub, Set1 predominantly localized to the 5' region of genes, while Swd2 lost all the chromatin binding. However, in the absence of Set1, Swd2 occupancy near the 5' region was impaired and rather increased in the 3' region. CONCLUSIONS: This study highlights that the catalytic activity of Rad6 is essential for all the ways of Swd2's binding to the transcribed genes and Set1 redistributes the Swd2 to the 5' region for accomplishments of H3K4me3 in the genome-wide level.


Assuntos
Histona-Lisina N-Metiltransferase , Histonas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Histonas/metabolismo , Histonas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Metilação , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética
2.
Angew Chem Int Ed Engl ; 63(15): e202401097, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38308505

RESUMO

It is highly challenging to reproducibly prepare semiconducting polymers with targeted molecular weight tailored for next-generation photovoltaic applications. Once such an easily accessible methodology is established, which can not only contribute to overcome the current limitation of the statistically determined nature of semiconducting polymers, but also facilitate rapid incorporation into the broad synthetic chemists' toolbox. Here, we describe a simple yet robust ultrasonication-assisted Stille polymerization for accessing semiconducting polymers with high-precision tailored molecular weights (from low to ultrahigh molecular weight ranges) while mitigating their interbatch variations. We propose that ultrasound-induced simultaneous physical and chemical events enable precise control of the semiconducting polymers' molecular weights with high reproducibility to satisfy all the optical/electrical and morphological demands of diverse types of high-performance semiconducting polymer-based devices; as demonstrated in in-depth experimental screenings in applications of both organic and perovskite photovoltaics. We believe that this methodology provides a fast development of new and existing semiconducting polymers with the highest-level performances possible on various photovoltaic devices.

3.
Immunology ; 168(3): 493-510, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36183156

RESUMO

Not only are many Mycobacteria pathogens, but they can act as strong non-specific immunopotentiators, generating beneficial effects on the pathogenesis of some diseases. However, there has been no direct evidence of the effect of mycobacterial species on colorectal cancer (CRC). Herein, we showed that there may be a meaningful inverse correlation between the incidence of tuberculosis and CRC based on global statistics and that heat-killed Mycobacterial tuberculosis and live Mycobacterium bovis (Bacillus Calmette-Guérin strain) could ameliorate CRC development. In particular, using a faecal microbiota transplantation and a comparison between separate housing and cohousing, we demonstrated that the gut microbiota is involved in the protective effects. The microbial alterations can be elucidated by the modulation of antimicrobial activities including those of the Reg3 family genes. Furthermore, interleukin-22 production by T helper cells contributed to the anti-inflammatory activity of Mycobacteria. Our results revealed a novel role of Mycobacteria involving gut microbial alterations in dampening inflammation-associated CRC and an immunological mechanism underlying the interaction between microbes and host immunity.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Humanos , Vacina BCG
4.
Small ; 19(27): e2300507, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37010009

RESUMO

Both organic solar cells (OSCs) and organic thermoelectrics (OTEs) are promising energy-harvesting technologies for future renewable and sustainable energy sources. Among various material systems, organic conjugated polymers are an emerging material class for the active layers of both OSCs and OTEs. However, organic conjugated polymers showing both OSC and OTE properties are rarely reported because of the different requirements toward the OSCs and OTEs. In this study, the first simultaneous investigation of the OSC and OTE properties of a wide-bandgap polymer PBQx-TF and its backbone isomer iso-PBQx-TF are reported. All wide-bandgap polymers form face-on orientations in a thin-film state, but PBQx-TF has more of a crystalline character than iso-PBQx-TF, originating from the backbone isomeric structures of α,α '/ß,ß '-connection between two thiophene rings. Additionally, iso-PBQx-TF shows inactive OSC and poor OTE properties, probably because of the absorption mismatch and unfavorable molecular orientations. At the same time, PBQx-TF exhibits both decent OSC and OTE performances, indicating that it satisfies the requirements for both OSCs and OTEs. This study presents the OSC and OTE dual-functional energy-harvesting wide-bandgap polymer and the future research directions for hybrid energy-harvesting materials.

5.
Small ; 19(12): e2206233, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36592416

RESUMO

Albeit considerable attention to the fast-developing organic thermoelectric (OTE) materials due to their flexibility and non-toxic features, it is still challenging to design an OTE polymer with superior thermoelectric properties. In this work, two "isomorphic" donor-acceptor (D-A) conjugated polymers are studied as the semiconductor in OTE devices, revealing for the first time the internal mechanism of regioregularity on thermoelectric performances in D-A type polymers. A higher molecular structure regularity can lead to higher crystalline order and mobility, higher doping efficiency, order of energy state, and thermoelectric (TE) performance. As a result, the regioregular P2F exhibits a maximum power factor (PF) of up to 113.27 µW m-1  K-2 , more than three times that of the regiorandom PRF (35.35 µW m-1  K-2 ). However, the regular backbone also implies lower miscibility with a dopant, negatively affecting TE performance. Therefore, the trade-off between doping efficiency and miscibility plays a vital role in OTE materials, and this work sheds light on the molecular design strategy of OTE polymers with state-of-the-art performances.

6.
Chemistry ; 29(45): e202300653, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37191934

RESUMO

Realizing efficient all-polymer solar cell (APSC) acceptors typically involves increased building block synthetic complexity, hence potentially unscalable syntheses and/or prohibitive costs. Here we report the synthesis, characterization, and implementation in APSCs of three new polymer acceptors P1-P3 using a scalable donor fragment, bis(2-octyldodecyl)anthra[1,2-b : 5,6-b']dithiophene-4,10-dicarboxylate (ADT) co-polymerized with the high-efficiency acceptor units, NDI, Y6, and IDIC. All three copolymers have comparable photophysics to known polymers; however, APSCs fabricated by blending P1, P2 and P3 with donor polymers PM5 and PM6 exhibit modest power conversion efficiencies (PCEs), with the champion P2-based APSC achieving PCE=5.64 %. Detailed morphological and microstructural analysis by AFM and GIWAXS reveal a non-optimal APSC active layer morphology, which suppresses charge transport. Despite the modest efficiencies, these APSCs demonstrate the feasibility of using ADT as a scalable and inexpensive electron rich/donor building block for APSCs.

7.
Phys Chem Chem Phys ; 25(25): 17001-17009, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37337735

RESUMO

All-polymer solar cells (all-PSCs), based on p-type polymer donors and n-type acceptors as the active layer, offer exceptional promise because of excellent thermal stability, superior film formation, and good mechanical stress as a unique bulk heterojunction (BHJ) solar cell combination. Therefore, tuning the molecular composition between polymers is crucial for optimizing power conversion efficiency (PCE) in these all-PSC systems. In this study, we synthesized a series of naphthalene diimide (NDI)-based random terpolymers P(NDI-BDD10), P(NDI-TPD10), P(NDI-TT10), and P(NDI-2FQ10) with axisymmetric (BDD, TPD) and asymmetric (TT, 2FQ) electron acceptors. Compared with the blend morphology of PBDB-T:N2200, their diverse effects due to the addition of trace amounts of axisymmetric and asymmetric components were comprehensively investigated using physical and surface analyses and structural simulations. Consequently, most of our polymer acceptors demonstrated improved fill factors (FFs) in the optimal morphology. P(NDI-BDD10)-based devices achieved the highest PCE of 6.80% and FF of 69.1%, while the architecturally most asymmetric P(NDI-TT10)-based devices reached the lowest PCE of 4.52% despite an enhanced FF of 65.4%. As a result, the appropriate molecular arrangement is crucial for obtaining the desired morphology and improved PCE. Our findings give novel molecular design insight into the distinctions between axisymmetric and asymmetric electron acceptors and seem significant for achieving improved morphological features and efficiency.

8.
Angew Chem Int Ed Engl ; 62(39): e202308267, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37539636

RESUMO

Single-component organic solar cells (SCOSCs) based on conjugated block copolymers (CBCs) by covalently bonding a polymer donor and polymer acceptor become more and more appealing due to the formation of a favorable and stable morphology. Unfortunately, a deep understanding of the effect of the assembly behavior caused by the sequence structure of CBCs on the device performance is still missing. Herein, from the aspect of manipulating the sequence length and distribution regularity of CBCs, we synthesized a series of new CBCs, namely D18(20)-b-PYIT, D18(40)-b-PYIT and D18(60)-b-PYIT by two-pot polymerization, and D18(40)-b-PYIT(r) by traditional one-pot method. It is observed that precise manipulation of sequence length and distribution regularity of the polymer blocks fine-tunes the self-assembly of the CBCs, optimizes film morphology, improves optoelectronic properties, and reduces energy loss, leading to simultaneously improved efficiency and stability. Among these CBCs, the D18(40)-b-PYIT-based device achieves a high efficiency of 13.4 % with enhanced stability, which is an outstanding performance among SCOSCs. Importantly, the regular sequence distribution and suitable sequence length of the CBCs enable a facile film-forming process of the printed device. For the first time, the blade-coated large-area rigid/flexible SCOSCs are fabricated, delivering an impressive efficiency of 11.62 %/10.73 %, much higher than their corresponding binary devices.

9.
Environ Microbiol ; 23(8): 4726-4740, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34296500

RESUMO

Faecalibacterium prausnitzii is a dominant member of healthy human colon microbiota, regarded as a beneficial gut bacterium due to its ability to produce anti-inflammatory substances. However, little is known about how F. prausnitzii utilizes the nutrients present in the human gut, influencing its prevalence in the host intestinal environment. The phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) is a widely distributed and highly efficient carbohydrate transport system found in most bacterial species that catalyses the simultaneous phosphorylation and import of cognate carbohydrates; its components play physiological roles through interaction with other regulatory proteins. Here, we performed a systematic analysis of the 16 genes encoding putative PTS components (2 enzyme I, 2 HPr, and 12 enzyme II components) in F. prausnitzii A2-165. We identified the general PTS components responsible for the PEP-dependent phosphotransfer reaction and the sugar-specific PTS components involved in the transport of two carbohydrates, N-acetylglucosamine and fructose, among five enzyme II complexes. We suggest that the dissection of the functional PTS in F. prausnitzii may help to understand how this species outcompetes other bacterial species in the human intestine.


Assuntos
Faecalibacterium prausnitzii , Fosfotransferases , Dissecação , Faecalibacterium prausnitzii/metabolismo , Humanos , Fosforilação , Fosfotransferases/genética , Fosfotransferases/metabolismo , Prevalência
10.
Biotechnol Bioeng ; 118(11): 4360-4374, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34309016

RESUMO

Excavating the molecular details of many diverse enzymes from metagenomes remains challenging in agriculture, food, health, and environmental fields. We present a versatile method that accelerates metabolic enzyme discovery for highly selective gene capture in metagenomes using next-generation sequencing. Culture-independent enzyme mining of environmental DNA is based on a set of short identifying degenerate sequences specific for a wide range of enzyme superfamilies, followed by multiplexed DNA barcode sequencing. A strategy of 'focused identification of next-generation sequencing-based definitive enzyme research' enabled us to generate targeted enzyme datasets from metagenomes, resulting in minimal hands-on obtention of high-throughput biological diversity and potential function profiles, without being time-consuming. This method also provided a targeted inventory of predicted proteins and molecular features of metabolic activities from several metagenomic samples. We suggest that the efficiency and sensitivity of this method will accelerate the decryption of microbial diversity and the signature of proteins and their metabolism from environmental samples.


Assuntos
Código de Barras de DNA Taxonômico , Enzimas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica
11.
Small ; 16(5): e1905309, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922652

RESUMO

A family of the SM-axis series based on benzo[1,​2-​b:4,​5-​b']​dithiophene and 3-ethylrhodanine (RD) units with structurally different π-conjugation systems are synthesized as a means to understand the structure-property relationship of conjugated pathways in ternary non-fullerene organic solar cells (NF-OSCs) as a third component. The optical and electrochemical properties of the SM-axis are highly sensitive both to the functionalized direction and to the number of RD groups. Enhanced power conversion efficiencies (PCEs) of over 11% in ternary devices are obtained by incorporating optimal SM-X and SM-Y contents from PBDB-T:ITIC binary NF-OSCs, while a slightly lower PCE is observed with the addition of SM-XY. The results of in-depth studies using various characterization techniques demonstrate that working mechanisms of SM-axis-based ternary NF-OSCs are distinctly different from one another: an energy-transfer mechanism with an alloy-like model for SM-X, a charge transfer with the same model for SM-Y, and an energy transfer without such a structure for SM-XY. As extension of the scope, a SM-X-based ternary NF-OSC in the PM6:IT4F system also shows a greatly enhanced PCE of over 13%. The findings provide insights into the effects of conjugated pathways of organic semiconductors on mechanisms of ternary NF-OSCs, advancing the understanding for synthetic chemists, materials engineers, and device physicists.

12.
Small ; 16(11): e1906635, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32072771

RESUMO

The functionalization of graphene has been extensively used as an effective route for modulating the surface property of graphene, and enhancing the dispersion stability of graphene in aqueous solutions via functionalization has been widely investigated to expand its use for various applications across a range of fields. Herein, an effective approach is described for enhancing the dispersibility of graphene in aqueous solutions at different pH levels via non-covalent zwitterion functionalization. The results show that a surfactant with electron-deficient carbon atoms in its backbone structure and large π-π interactive area enables strong interactions with graphene, and the zwitterionic side terminal groups of the molecule support the dispersibility of graphene in various pH conditions. Experimental and computational studies confirm that perylene diimide amino N-oxide (PDI-NO) allows efficient functionalization and pH-independent dispersion of graphene enabled by hydration repulsion effects induced by PDI-NO. The PDI-NO functionalized graphene is successfully used in the oxygen evolution reaction as an electron mediator for boosting the electrocatalytic activity of a Ru-based polyoxometalate catalyst in an acidic medium. The proposed strategy is expected to bring significant advances in producing highly dispersible graphene in aqueous medium with pH-independent stability, thus broadening the application range of graphene.

13.
Int J Syst Evol Microbiol ; 70(11): 5918-5925, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33034550

RESUMO

Two Gram-stain-negative, facultative anaerobic, chemoheterotrophic, pink-coloured, rod-shaped and non-motile bacterial strains, PAMC 26568 and PAMC 26569T, were isolated from an Antarctic lichen. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains PAMC 26568 and PAMC 26569T belong to the family Acetobacteraceae and the most closely related species are Gluconacetobacter takamatsuzukensis (96.1 %), Gluconacetobacter tumulisoli (95.9 %) and Gluconacetobacter sacchari (95.7 %). Phylogenomic and genomic relatedness analyses showed that strains PAMC 26568 and PAMC 26569T are clearly distinguished from other genera in the family Acetobacteraceae by average nucleotide identity values (<72.8 %) and the genome-to-genome distance values (<22.5 %). Genomic analysis revealed that strains PAMC 26568 and PAMC 26569T do not contain genes involved in atmospheric nitrogen fixation and utilization of sole carbon compounds such as methane and methanol. Instead, strains PAMC 26568 and PAMC 26569T possess genes to utilize nitrate and nitrite and certain monosaccharides and disaccharides. The major fatty acids (>10 %) are summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c; 40.3-40.4 %), C18 : 1 2OH (22.7-23.7 %) and summed feature 2 (C14 : 0 3OH and/or C16 : 1 iso I; 12.0 % in PAMC 26568). The major respiratory quinone is Q-10. The genomic DNA G+C content of PAMC 26568 and PAMC 26569T is 64.6 %. Their distinct phylogenetic position and some physiological characteristics distinguish strains PAMC 26568 and PAMC 26569T from other genera in the family Acetobacteraceae supporting the proposal of Lichenicola gen. nov., with the type species Lichenicola cladoniae sp. nov. (type strain, PAMC 26569T=KCCM 43315T=JCM 33604T).


Assuntos
Acetobacteraceae/classificação , Líquens/microbiologia , Filogenia , Acetobacteraceae/isolamento & purificação , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
14.
Proc Natl Acad Sci U S A ; 114(38): 10232-10237, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28874555

RESUMO

Bacteria use flagella to move toward nutrients, find its host, or retract from toxic substances. Because bacterial flagellum is one of the ligands that activate the host innate immune system, its synthesis should be tightly regulated during host infection, which is largely unknown. Here, we report that a bacterial leader mRNA from the mgtCBR virulence operon in the intracellular pathogen Salmonella enterica serovar Typhimurium binds to the fljB coding region of mRNAs in the fljBA operon encoding the FljB phase 2 flagellin, a main component of bacterial flagella and the FljA repressor for the FliC phase 1 flagellin, and degrades fljBA mRNAs in an RNase E-dependent fashion during infection. A nucleotide substitution of the fljB flagellin gene that prevents the mgtC leader RNA-mediated down-regulation increases the fljB-encoded flagellin synthesis, leading to a hypermotile phenotype inside macrophages. Moreover, the fljB nucleotide substitution renders Salmonella hypervirulent, indicating that FljB-based motility must be compromised in the phagosomal compartment where Salmonella resides. This suggests that this pathogen promotes pathogenicity by producing a virulence protein and limits locomotion by a trans-acting leader RNA from the same virulence gene during infection.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Transporte de Cátions/genética , Flagelina/metabolismo , Regulação Bacteriana da Expressão Gênica , Salmonella typhimurium/genética , Regiões 5' não Traduzidas , Substituição de Aminoácidos , Proteínas de Bactérias/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Endorribonucleases/metabolismo , Fator Proteico 1 do Hospedeiro/metabolismo , Macrófagos/microbiologia , Magnésio/metabolismo , Óperon , Salmonella typhimurium/metabolismo , Salmonella typhimurium/patogenicidade , Transativadores
15.
Angew Chem Int Ed Engl ; 57(41): 13629-13634, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30133093

RESUMO

To understand the effects rendered on the relevant basic physical properties and device function by controlling the regiochemistry of the cyclopenta[1,2-b:5,4-b']dithiophene-fluorobenzo[c][1,2,5]thiadiazole polymer (hereafter referred to as the CDT-FBT polymer), two polymers, the regiorandom polymer (RA) and regioregular version (RR), respectively, are synthesized and characterized. In addition, an efficient route for synthesizing a key monomer for RR using various synthesis scope and optimizing the reaction conditions is discussed. Although RA exhibits optical, electrochemical, and morphological properties similar to RR, it shows better field-effect transistor (FET) performance. Surprisingly, by employing a capillarity-mediated sandwich-casting process on a nanogrooved substrate, an unprecedented mobility of 17.8 cm2 V-1 s-1 is obtained for RA-based FETs; this mobility value is almost twofold greater than those of the corresponding RR-based FETs. For the first time, this study challenges previously reported results in that high carrier mobility is related to the high degree of polymer order induced by the backbone regioregularity.

16.
Angew Chem Int Ed Engl ; 57(40): 13277-13282, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30113743

RESUMO

Considering the potential applications of all-polymer solar cells (all-PSCs) as wearable power generators, there is an urgent need to develop photoactive layers that possess intrinsic mechanical endurance, while maintaining a high power-conversion efficiency (PCE).Herein a strategy is demonstrated to simultaneously control the intercalation behavior and nanocrystallite size in the polymer-polymer blend by using a newly developed, high-viscosity polymeric additive, poly(dimethylsiloxane-co-methyl phenethylsiloxane) (PDPS), into the TQ-F:N2200 all-PSC matrix. A mechanically robust 10wt% PDPS blend film with a great toughness was obtained. Our results provide a feasible route for producing high-performance ductile all-PSCs, which can potentially be used to realize stretchable all-PSCs as a linchpin of next-generation electronics.

17.
Int J Syst Evol Microbiol ; 67(1): 153-157, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27902216

RESUMO

A cream-coloured, non-gliding, aerobic Flavobacterium strain, designated EM1308T, was isolated from stream water. 16S rRNA gene sequence analysis indicated that this isolate is closely related to Flavobacterium glycines NBRC 105008T (97.3 % similarity) and Flavobacterium piscis CCUG 60099T (97.2 %). To evaluate the genomic relatedness of the isolate with its neighbours, the whole genome sequences of strain EM1308T and the type strains of F. glycines and F. piscis were determined. Average nucleotide identities revealed that strain EM1308T is independent from other Flavobacterium species. The properties of major cellular fatty acids, polar lipids, menaquinone and DNA G+C content of the isolate were within the general range for the genus Flavobacterium, but many biochemical and physiological characteristics distinguished the isolate from previously known species. Thus, strain EM1308T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium gilvum sp. nov. is proposed. The type strain is EM1308T (=KACC 18113T=JCM 30144T).

18.
Mycoses ; 60(3): 188-197, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27882618

RESUMO

Malassezia species are opportunistic pathogenic fungi that are frequently associated with seborrhoeic dermatitis, including dandruff. Most Malassezia species are lipid dependent, a property that is compensated by breaking down host sebum into fatty acids by lipases. In this study, we aimed to sequence and analyse the whole genome of Malassezia restricta KCTC 27527, a clinical isolate from a Korean patient with severe dandruff, to search for lipase orthologues and identify the lipase that is the most frequently expressed on the scalp of patients with dandruff. The genome of M. restricta KCTC 27527 was sequenced using the Illumina MiSeq and PacBio platforms. Lipase orthologues were identified by comparison with known lipase genes in the genomes of Malassezia globosa and Malassezia sympodialis. The expression of the identified lipase genes was directly evaluated in swab samples from the scalps of 56 patients with dandruff. We found that, among the identified lipase-encoding genes, the gene encoding lipase homolog MRES_03670, named LIP5 in this study, was the most frequently expressed lipase in the swab samples. Our study provides an overview of the genome of a clinical isolate of M. restricta and fundamental information for elucidating the role of lipases during fungus-host interaction.


Assuntos
Caspa/microbiologia , Genoma Fúngico , Lipase/genética , Malassezia/enzimologia , Malassezia/genética , Couro Cabeludo , Dermatite Seborreica/microbiologia , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Humanos , Lipase/isolamento & purificação , Malassezia/isolamento & purificação , Malassezia/patogenicidade , Filogenia , Couro Cabeludo/microbiologia , Alinhamento de Sequência
19.
BMC Genomics ; 17: 345, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27165035

RESUMO

BACKGROUND: Plant-pathogen interactions at early stages of infection are important to the fate of interaction. Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight, which is a devastating disease in rice. Although in vivo and in vitro systems have been developed to study rice-Xoo interactions, both systems have limitations. The resistance mechanisms in rice can be better studied by the in vivo approach, whereas the in vitro systems are suitable for pathogenicity studies on Xoo. The current in vitro system uses minimal medium to activate the pathogenic signal (expression of pathogenicity-related genes) of Xoo, but lacks rice-derived factors needed for Xoo activation. This fact emphasizes the need of developing a new in vitro system that allow for an easy control of both pathogenic activation and for the experiment itself. RESULTS: We employed an in vitro system that can activate pathogenicity-related genes in Xoo using rice leaf extract (RLX) and combined the in vitro assay with RNA-Seq to analyze the time-resolved genome-wide gene expression of Xoo. RNA-Seq was performed with samples from seven different time points within 1 h post-RLX treatment and the expression of up- or downregulated genes in RNA-Seq was validated by qRT-PCR. Global analysis of gene expression and regulation revealed the most dramatic changes in functional categories of genes related to inorganic ion transport and metabolism, and cell motility. Expression of many pathogenicity-related genes was induced within 15 min upon contact with RLX. hrpG and hrpX expression reached the maximum level within 10 and 15 min, respectively. Chemotaxis and flagella biosynthesis-related genes and cyclic-di-GMP controlling genes were downregulated for 10 min and were then upregulated. Genes related to inorganic ion uptake were upregulated within 5 min. We introduced a non-linear regression fit to generate continuous time-resolved gene expression levels and tested the essentiality of the transcriptionally upregulated genes by a pathogenicity assay of lesion length using single-gene knock-out Xoo strains. CONCLUSIONS: The in vitro system combined with RNA-Seq generated a genome-wide time-resolved pathogenic gene expression profile within 1 h of initial rice-Xoo interactions, demonstrating the expression order and interaction dependency of pathogenic genes. This combined system can be used as a novel tool to study the initial interactions between rice and Xoo during bacterial blight progression.


Assuntos
Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Transcriptoma , Xanthomonas/genética , Análise por Conglomerados , Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Anotação de Sequência Molecular , Oryza/microbiologia , Doenças das Plantas/microbiologia
20.
Int J Syst Evol Microbiol ; 64(Pt 2): 689-691, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24425826

RESUMO

EzEditor is a Java-based molecular sequence editor allowing manipulation of both DNA and protein sequence alignments for phylogenetic analysis. It has multiple features optimized to connect initial computer-generated multiple alignment and subsequent phylogenetic analysis by providing manual editing with reference to biological information specific to the genes under consideration. It provides various functionalities for editing rRNA alignments using secondary structure information. In addition, it supports simultaneous editing of both DNA sequences and their translated protein sequences for protein-coding genes. EzEditor is, to our knowledge, the first sequence editing software designed for both rRNA- and protein-coding genes with the visualization of biologically relevant information and should be useful in molecular phylogenetic studies. EzEditor is based on Java, can be run on all major computer operating systems and is freely available from http://sw.ezbiocloud.net/ezeditor/.


Assuntos
RNA Ribossômico/genética , Alinhamento de Sequência/métodos , Software , Sequência de Aminoácidos , Sequência de Bases , Biologia Computacional , Filogenia , Linguagens de Programação
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