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1.
Mol Biol Rep ; 51(1): 70, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175288

RESUMO

BACKGROUND: The tea tree (Melaleuca alternifolia) is renowned for its production of tea tree oil, an essential oil primarily composed of terpenes extracted from its shoot. MYB transcription factors, which are one of the largest TF families, play a crucial role in regulating primary and secondary metabolite synthesis. However, knowledge of the MYB gene family in M. alternifolia is limited. METHODS AND RESULTS: Here, we conducted a comprehensive genome-wide analysis of MYB genes in M. alternifolia, referred to as MaMYBs, including phylogenetic relationships, structures, promoter regions, and GO annotations. Our findings classified 219 MaMYBs into four subfamilies: one 5R-MYB, four 3R-MYBs, sixty-one MYB-related, and the remaining 153 are all 2R-MYBs. Seven genes (MYB189, MYB146, MYB44, MYB29, MYB175, MYB162, and MYB160) were linked to terpenoid synthesis based on GO annotation. Phylogenetic analysis with Arabidopsis homologous MYB genes suggested that MYB193 and MYB163 may also be involved in terpenoid synthesis. Additionally, through correlation analysis of gene expression and metabolite content, we identified 42 MYB genes associated with metabolite content. CONCLUSION: The results provide valuable insights into the importance of MYB transcription factors in essential oil production in M. alternifolia. These findings lay the groundwork for a better understanding of the MYB regulatory network and the development of novel strategies to enhance essential oil synthesis in M. alternifolia.


Assuntos
Arabidopsis , Melaleuca , Óleos Voláteis , Genes myb , Melaleuca/genética , Filogenia , Chás Medicinais , Fatores de Transcrição/genética , Terpenos
2.
J Nat Prod ; 87(5): 1376-1383, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38662398

RESUMO

A precursor-directed biosynthesis approach led to the accumulation of seven new neoantimycin derivatives (1-7) from Streptomyces conglobatus RJ2. Structure elucidation was conducted using NMR and HRESIMS analysis, and the absolute configuration was determined by advanced Marfey's method, Mosher's analysis, and ECD analysis. The obtained compounds revealed selective and significant cytotoxicity, specifically against colorectal cancer cells bearing the K-ras mutation, with IC50 values ranging from 40 nM to 3.5 µM.


Assuntos
Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Mutação , Ressonância Magnética Nuclear Biomolecular , Compostos Orgânicos
3.
Angew Chem Int Ed Engl ; 63(2): e202315302, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38009464

RESUMO

Nitrogen-doped cavities are pervasive in graphenic materials, and represent key sites for catalytic and electrochemical activity. However, their structures are generally heterogeneous. In this study, we present the synthesis of a well-defined molecular cutout of graphene featuring N-doped cavity. The graphitization of a macrocyclic pyridinic precursor was achieved through photochemical cyclodehydrochlorination. In comparison to its counterpart with pyridinic nitrogen at the edges, the pyridinic nitrogen atoms in this nanographene cavity exhibit significantly reduced basicity and selective binding to Ag+ ion. Analysis of the protonation and coordination equilibria revealed that the tri-N-doped cavity binds three protons, but only one Ag+ ion. These distinct protonation and coordination behaviors clearly illustrate the space confinement effect imparted by the cavities.

4.
J Am Chem Soc ; 145(5): 2815-2821, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36705468

RESUMO

The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

5.
Mol Biol Rep ; 50(2): 1545-1552, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36513867

RESUMO

BACKGROUND: Melaleuca alternifolia is a commercially important medicinal tea tree native to Australia. Tea tree oil, the essential oil distilled from its branches and leaves, has broad-spectrum germicidal activity and is highly valued in the pharmaceutical and cosmetic industries. Thus, the study of genome, which can provide reference for the investigation of genes involved in terpinen-4-ol biosynthesis, is quite crucial for improving the productivity of Tea tree oil. METHODS AND RESULTS: In our study, the next-generation sequencing was used to investigate the whole genome of Melaleuca alternifolia. About 114 Gb high quality sequence data were obtained and assembled into 1,838,159 scafolds with an N50 length of 1021 bp. The assembled genome size is about 595 Mb, twice of that predicted by flow cytometer (300 Mb) and k-mer analysis (345 Mb). Benchmarking Universal Single-Copy Orthologs analyses indicated that only 11.3% of the conserved single-copy genes were miss. Repetitive regions cover over 40.43% of the genome. A total of 44,369 protein-coding genes were predicted and annotated against Nr, Swissprot, Refseq, COG, KOG, and KEGG database. Among these genes, 32,909 and 16,241 genes were functionally annotated in Nr and KEGG, respectively. Moreover, 29,411 and 14,435 genes were functionally annotated in COG and KOG. Additionally, 457,661 simple sequence repeats and 1109 transcription factors (TFs) form 67 TF families were identified in the assembled genome. CONCLUSION: Our findings provide a draft genome sequencing of M. alternifolia which can act as a reference for the deep sequencing strategies, and are useful for future functional and comparative genomics analyses.


Assuntos
Melaleuca , Óleos Voláteis , Óleo de Melaleuca , Humanos , Melaleuca/genética , Árvores , Chás Medicinais
6.
J Nat Prod ; 86(4): 994-1002, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36947873

RESUMO

Seven new 18-residue peptaibols, trichorzins A-G (1-7), were isolated from the sponge-derived fungus Trichoderma sp. GXIMD 01001. Their structures and configurations were characterized by a comprehensive interpretation of the NMR spectroscopic data, MS/MS fragmentation, Marfey's method, and ECD analysis. The general sequences of trichorzins A-G are as follows: Ac-Aib1-Ala/Ser2-Ala3-Aib/Iva4-Iva5-Gln6-Aib/Iva7-Val/allo-Ile8-Aib9-Gly10-Leu11-Aib12-Pro13-Leu14-Aib15-Aib16-Gln17-Trpol/Pheol18. The obtained compounds were assessed for their potential antiproliferative and antimicrobial activities. All obtained compounds did not show potent antibacterial activity but exhibited significant cytotoxicity, with the lowest IC50 values at 0.46-4.7 µM against four human carcinoma cell lines.


Assuntos
Peptaibols , Trichoderma , Humanos , Peptaibols/química , Trichoderma/química , Espectrometria de Massas em Tandem , Antibacterianos/química
7.
Plant Dis ; 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709725

RESUMO

Coconut (Cocos nucifera) is a high economic value cash crop in Malaysia. In December 2021, irregular spots with dotted rust-like appearance were observed mainly on the tip of the leaves of MATAG variety coconut seedlings at the nursery in Perak state. More than 90% of the coconut seedlings surveyed were infected with leaf spot symptoms. These symptoms could bring huge economic losses due to the downgrade value of the seedlings. 15 symptomatic leaves were obtained from the nursery, 10 mm2 of cut leaves were disinfected with 10% sodium hypochlorite for 10 minutes and rinsed with sterile distilled water before plated on potato dextrose agar (PDA). A total of 4 single-spore isolates were obtained and were observed morphologically. The isolates had white cotton-like appearance with undulate edge. Black acervuli were seen after 7 days of incubation at 26 °C. The conidia were fusiform and contained five cells with four septate and three versicolor cells in between the apical and basal cell. The conidia were 17.2 µm long and 5.9 µm wide (n=30). Conidia consisted of two to three apical appendages and one basal appendage. These morphological characters were consistent with the original description of Neopestalotiopsis clavispora (Santos et al., 2019; Abbas et al., 2022). Species identification was done by amplifying internal transcribed spacer (ITS) region using primers ITS 4 and ITS 5 (White et al., 1990) and beta-tubulin (TUB2) using primers Bt2a and Bt2b (Glass & Donaldson et al., 1995) of the representative isolate LKR1, then sequenced. The 488 bp ITS and 409 bp TUB2 sequences were deposited in GenBank under the accession numbers ON844193 and OP004810, respectively. Isolate LKR1 shares 99.8% identity with the ITS sequence (MH860736.1) of the reference pathogenic N. clavispora strain CBS:447.73 and 100% identity with the TUB2 sequence (KM199443.1) of the reference pathogenic N. clavispora strain CBS 447.73. The phylogenetic analysis confirmed that the isolate LKR1 belonged to N. clavispora when a supported clade is formed with 98% and 94% bootstrap support for ITS and TUB2 respectively with other related N. clavispora. Pathogenicity test was conducted by using five replicates of 8 month old seedlings, they were incubated under greenhouse condition and were watered daily. The leaves of the seedlings were injured with sterile needles and were sprayed with conidial suspension (1 x 10^6 conidia/ml). The control plants were also injured but sprayed with sterile distilled water. After a month, signature symptoms of spots on the leaves appear but none on the control seedling. N. clavispora was successfully re-isolated only from the inoculated symptomatic leaves and identified morphologically. No fungus was re-isolated from the control seedlings. The result was consistent even after repeating the test one more time. N. clavispora has been reported causing leaf spot on Macadamia integrifolia (Santos et al., 2019), Phoenix dactylifera L. (Basavand et al., 2020) and Musa acuminata (Qi et al., 2022). N. clavispora has also been reported causing rust-like appearance of leaves on strawberry (Fragaria × ananassa Duch.) (Obregón et al., 2018). To our knowledge, this is the first report of N. clavispora causing leaf spot disease on coconut seedlings in Malaysia. Through the identification of N. clavispora as the causal agent of leaf spot on coconut, this can help coconut growers to tackle the disease problem earlier thus, preventing the disease from spreading until the adult phase.

8.
World J Microbiol Biotechnol ; 39(5): 123, 2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36934342

RESUMO

In today's fast-shifting climate change scenario, crops are exposed to environmental pressures, abiotic and biotic stress. Hence, these will affect the production of agricultural products and give rise to a worldwide economic crisis. The increase in world population has exacerbated the situation with increasing food demand. The use of chemical agents is no longer recommended due to adverse effects towards the environment and health. Biocontrol agents (BCAs) and biostimulants, are feasible options for dealing with yield losses induced by plant stresses, which are becoming more intense due to climate change. BCAs and biostimulants have been recommended due to their dual action in reducing both stresses simultaneously. Although protection against biotic stresses falls outside the generally accepted definition of biostimulant, some microbial and non-microbial biostimulants possess the biocontrol function, which helps reduce biotic pressure on crops. The application of synergisms using BCAs and biostimulants to control crop stresses is rarely explored. Currently, a combined application using both agents offer a great alternative to increase the yield and growth of crops while managing stresses. This article provides an overview of crop stresses and plant stress responses, a general knowledge on synergism, mathematical modelling used for synergy evaluation and type of in vitro and in vivo synergy testing, as well as the application of synergism using BCAs and biostimulants in reducing crop stresses. This review will facilitate an understanding of the combined effect of both agents on improving crop yield and growth and reducing stress while also providing an eco-friendly alternative to agroecosystems.


Assuntos
Agricultura , Estresse Fisiológico , Produtos Agrícolas , Mudança Climática
9.
BMC Genomics ; 23(1): 164, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35219299

RESUMO

BACKGROUND: The ability of plants to withstand and thrive in an adverse environment is crucial to ensure their survivability and yield performance. The WRKY transcription factors (TFs) have crucial roles in plant growth, development and stress response, particularly drought stress. In oil palm, drought is recognized as one of the major yield limiting factors. However, the roles of WRKY TFs in the drought response of oil palm is unclear. RESULTS: Herein, we studied the transcriptome of drought treated oil palm leaf and identified 40 differentially expressed genes (DEGs) of WRKY TFs, of which 32 DEGs were upregulated and 8 DEGs were downregulated in response to drought stress in oil palm. They were categorized into Groups I to IV based on the numbers of WRKY domain and the structural difference in the zinc finger domain. Multiple stress- and hormone-responsive cis-regulatory elements were detected in the drought responsive oil palm EgWRKY (Dro-EgWRKY) genes. Fourteen of the 15 selected oil palm WRKY (EgWRKY) genes demonstrated a tissue-specific expression profile except for EgWRKY28 (Group I), which was expressed in all tissues tested. The expression levels of 15 candidate EgWRKYs were upregulated upon salinity and heat treatments, while several genes were also inducible by abscisic acid, methyl jasmonate, salicylic acid and hydrogen peroxide treatments. Members of the Group III WRKY TFs including EgWRKY07, 26, 40, 52, 59, 73 and 81 displayed multiple roles in drought- and salinity-response under the modulation of phytohormones. CONCLUSIONS: EgWRKY TFs of oil palm are involved in phytohormones and abiotic stress responses including drought, salinity and heat. EgWRKY07, 26, 59 and 81 from Group III maybe important regulators in modulating responses of different abiotic stresses. Further functional analysis is required to understand the underlying mechanism of WRKY TFs in the regulatory network of drought stress.


Assuntos
Arecaceae , Secas , Regulação da Expressão Gênica de Plantas , Hormônios , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Angew Chem Int Ed Engl ; 61(38): e202210268, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35899409

RESUMO

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π-π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C60 or C70 , the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C60 or C70 molecules. The formed host-guest complex demonstrated efficient energy transfer from the diazananographene shell to the C60 cores. The emission intensity of the capsulated C60 was enhanced remarkably, compared with free C60 , due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene-based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non-emissive fullerene.

11.
Pain Manag Nurs ; 22(3): 268-280, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32950391

RESUMO

OBJECTIVES: This systematic review aimed to summarize and provide an update on clinical studies investigating the effects of auricular point acupressure (APA) on pain relief, in addition to the APA methods of delivery and operation. DESIGN: A systematic review. DATA SOURCES: A systematic review on literatures published on five English (PubMed, Web of Science, Embase, EBSCO, and Cochrane databases) and four major Chinese databases (China National Knowledge Infrastructure, Wan Fang Data, Chinese Scientific Journals Database [VIP], and SinoMed) was conducted. METHOD: We screened nine electronic databases from the time of their respective establishment until December 20, 2019. Randomized controlled trials and studies that defined an APA intervention measure and evaluated pain intensity were considered. We individually categorized and analyzed 46 studies considering the following: (1) acute or chronic pain and (2) whether the outcomes positively or negatively support the effectiveness of APA on pain intensity. We also summarized the methods of delivery used (including the acupoint selection, stimulator selection, method of taping seeds on the ears, frequency of replacing seeds, suitability of acupressure intensity, acupressure frequency, and pressing time) and APA operator. RESULTS: Regardless of pain intensity, APA effectively treated most acute pain when combined with other interventions. Although it was used alone to treat low back pain and dysmenorrhea, other chronic diseases typically underwent a combination of APA with other interventions. The 43 positive studies revealed that acute pain required shorter APA intervention periods than chronic pain. Corresponding acupoints and nervous system acupoints were chosen. Vaccaria seeds, the single-ear method (including the alternate-ear method), and daily seed replacement were commonly adopted. Deqi was considered an effective signal for appropriate acupressure intensity. Additionally, the patients could effectively apply acupressure. CONCLUSION: This systematic review revealed important trends in APA treatments, which could be essential in determining treatment efficacy.


Assuntos
Acupressão , Dor Crônica , Manejo da Dor , Pontos de Acupuntura , Dor Crônica/terapia , Pavilhão Auricular , Humanos
12.
Genomics ; 112(2): 1536-1544, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31494197

RESUMO

Red algae are a major source of marine sulfated galactans. In this study, orthologs and inparalogs from seven red algae were analyzed and compared with the aim to discover differences in algal galactan biosynthesis and related pathways of these algae. Red algal orthologs for putative carbohydrate sulfotransferases were found to be prevalent in Porphyridium purpureum, Florideophytes and Bangiophytes, while red algal orthologs for putative chondroitin sulfate synthases, sulfurylases, and porphyranases /carrageenases were found exclusively in Florideophytes and Bangiophytes. The acquirement of these genes could have happened after the divergence from Cyanidiales red algae. Cyanidiales red algae were found to have more number and types of putative sulfate permeases, suggesting that these genes could have been acquired in adaptation to the environmental stresses and biogeochemistry of respective habitats. The findings of this study shed lights on the evolution of different homeostasis mechanisms by the early and late diverging red algal orders.


Assuntos
Galactanos/biossíntese , Especiação Genética , Genoma de Planta , Porphyridium/genética , Galactanos/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Porphyridium/classificação , Sulfotransferases/genética , Sulfotransferases/metabolismo , Carboidrato Sulfotransferases
13.
Plant Cell Environ ; 42(5): 1657-1673, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30549047

RESUMO

Abiotic stress reduces plant growth and crop productivity. However, the mechanism underlying posttranscriptional regulations of stress response remains elusive. Herein, we report the posttranscriptional mechanism of nucleocytoplasmic RNA transport of stress-responsive transcripts mediated by EgRBP42, a heterogeneous nuclear ribonucleoprotein-like RNA-binding protein from oil palm, which could be necessary for rapid protein translation to confer abiotic stress tolerance in plants. Transgenic Arabidopsis overexpressing EgRBP42 showed early flowering through alteration of gene expression of flowering regulators and exhibited tolerance towards heat, cold, drought, flood, and salinity stresses with enhanced poststress recovery response by increasing the expression of its target stress-responsive genes. EgRBP42 harbours nucleocytoplasmic shuttling activity mediated by the nuclear localization signal and the M9-like domain of EgRBP42 and interacts directly with regulators in the nucleus, membrane, and the cytoplasm. EgRBP42 regulates the nucleocytoplasmic RNA transport of target stress-responsive transcripts through direct binding to their AG-rich motifs. Additionally, EgRBP42 transcript and protein induction by environmental stimuli are regulated at the transcriptional and posttranscriptional levels. Taken together, the posttranscriptional regulation of RNA transport mediated by EgRBP42 may change the stress-responsive protein profiles under abiotic stress conditions leading to a better adaptation of plants to environmental changes.


Assuntos
Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Adaptação Fisiológica/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/farmacologia , Estresse Fisiológico , Arabidopsis/genética , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas de Ligação a RNA/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
14.
Crit Rev Food Sci Nutr ; 59(sup1): S17-S29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30040451

RESUMO

Andrographis paniculata (A. paniculata) is a medicinal plant traditionally used as anti-inflammation and anti-bacteria herb. Andrographolide, the major active component of A. paniculata, exhibits diverse pharmacological activities, including anti-inflammation, anti-cancer, anti-obesity, anti-diabetes, and other activities. In this article, we comprehensively review the therapeutic potential of A. paniculata and andrographolide focusing on the mechanisms of action and clinical application. We systemically discuss the structure-activity relationship of andrographolide and derivatives. Despite the various pharmacological activities and formula of A. paniculata and andrographolide, we propose further development of more structural derivatives of andrographolide with reduced toxicity and increased therapeutic efficacy is still needed for the clinical application of this ancient mighty herb and its major component.


Assuntos
Andrographis/química , Diterpenos/farmacologia , Inflamação/tratamento farmacológico , Fitoterapia , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antimaláricos/farmacologia , Antineoplásicos/farmacologia , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Terapia de Imunossupressão , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Relação Estrutura-Atividade
15.
Pain Manag Nurs ; 20(2): 174-182, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30268440

RESUMO

BACKGROUND: Since the 2010s, the Pain Resource Nurse (PRN) program and similar programs have been introduced in Chinese hospitals. However, the status of the PRN program and nurses' experiences in these programs remain unclear. AIMS: The aim of the study was to identify the factors related to PRN programs and explore PRNs' experiences being part of the program. DESIGN: A combination of descriptive cross-sectional and qualitative methods was used in the study. SETTINGS: Thirty-two hospitals in the eastern, central, and western regions of China. PARTICIPANTS/SUBJECTS: Twenty-four PRNs who had been PRNs for 6 months or more. METHODS: A purposive sample of 32 hospitals from eastern, central, and western regions of China carried out a PRN or similar program for more than 1 year with at least five bedside nurses from different nursing units were enrolled in the descriptive cross-sectional study. The questionnaire was designed by Brown's advanced nursing practice framework theory. A total of 24 PRNs who had been PRNs for 6 months or more participated in the interview by convenience and purposive sampling. RESULTS: The mean number of PRNs in a program was 30.12 ± 17.93 (range 5-74). The role of the PRN was broader compared with that of bedside nurses, and it included pain management, training, and education. The most common reason for hospitals to establish PRN programs was to improve the quality of pain management (n = 28, 87.5%). Administrative support (n = 28, 87.5%) was a major supportive factor for PRN programs and lack of physician support (n = 28, 87.5%) was a barrier. Although all hospitals provided training, those with knowledge assessments after training indicated a significant improvement in the desired PRN functions compared with those that did not (p < .05). Personal interviews revealed that the reasons for becoming a PRN varied and included considering PRN as a career opportunity, personal interest, passively accepting the designation, and being a PRN temporarily. The positive professional experiences of being a PRN included an increased sense of self-worth and accomplishment and growth in a specialty, whereas the negative experiences included frustration with the work environment and resignation because of extra workload. CONCLUSIONS: The hospital survey results indicated that the PRN program in China is still in the early development stage. The PRN interviews suggest that being a PRN involves both positive and negative experiences.


Assuntos
Dor/enfermagem , Especialidades de Enfermagem/tendências , China , Estudos Transversais , Humanos , Pesquisa Qualitativa , Especialidades de Enfermagem/estatística & dados numéricos , Local de Trabalho
16.
Genomics ; 110(2): 124-133, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28890206

RESUMO

Agar and agarose have wide applications in food and pharmaceutical industries. Knowledge on the genome of red seaweeds that produce them is still lacking. To fill the gap in genome analyses of these red algae, we have sequenced the nuclear and organellar genomes of an agarophyte, Gracilaria changii. The partial nuclear genome sequence of G. changii has a total length of 35.8Mb with 10,912 predicted protein coding sequences. Only 39.4% predicted proteins were found to have significant matches to protein sequences in SwissProt. The chloroplast genome of G. changii is 183,855bp with a total of 201 open reading frames (ORFs), 29 tRNAs and 3 rRNAs predicted. Five genes: ssrA, leuC and leuD CP76_p173 (orf139) and pbsA were absent in the chloroplast genome of G. changii. The genome information is valuable in accelerating functional studies of individual genes and resolving evolutionary relationship of red seaweeds.


Assuntos
Genoma de Cloroplastos , Gracilaria/genética , Gracilaria/classificação , Anotação de Sequência Molecular , Fases de Leitura Aberta , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , Homologia de Sequência , Sequenciamento Completo do Genoma
17.
Molecules ; 24(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319614

RESUMO

Kefir is a homemade, natural fermented product comprised of a probiotic bacteria and yeast complex. Kefir consumption has been associated with many advantageous properties to general health, including as an antioxidative, anti-obesity, anti-inflammatory, anti-microbial, and anti-tumor moiety. This beverage is commonly found and consumed by people in the United States of America, China, France, Brazil, and Japan. Recently, the consumption of kefir has been popularized in other countries including Malaysia. The microflora in kefir from different countries differs due to variations in culture conditions and the starter media. Thus, this study was aimed at isolating and characterizing the lactic acid bacteria that are predominant in Malaysian kefir grains via macroscopic examination and 16S ribosomal RNA gene sequencing. The results revealed that the Malaysian kefir grains are dominated by three different strains of Lactobacillus strains, which are Lactobacillus harbinensis, Lactobacillusparacasei, and Lactobacillus plantarum. The probiotic properties of these strains, such as acid and bile salt tolerances, adherence ability to the intestinal mucosa, antibiotic resistance, and hemolytic test, were subsequently conducted and extensively studied. The isolated Lactobacillus spp. from kefir H maintained its survival rate within 3 h of incubation at pH 3 and pH 4 at 98.0 ± 3.3% and 96.1 ± 1.7% of bacteria growth and exhibited the highest survival at bile salt condition at 0.3% and 0.5%. The same isolate also showed high adherence ability to intestinal cells at 96.3 ± 0.01%, has antibiotic resistance towards ampicillin, penicillin, and tetracycline, and showed no hemolytic activity. In addition, the results of antioxidant activity tests demonstrated that isolated Lactobacillus spp. from kefir G possessed high antioxidant activities for total phenolic content (TPC), total flavonoid content (TFC), ferric reducing ability of plasma (FRAP), and 1,1-diphenyl-2-picryl-hydrazine (DPPH) assay compared to other isolates. From these data, all Lactobacillus spp. isolated from Malaysian kefir serve as promising candidates for probiotics foods and beverage since they exhibit potential probiotic properties and antioxidant activities.


Assuntos
Antioxidantes/química , Kefir/microbiologia , Lactobacillus plantarum/isolamento & purificação , Lactobacillus/isolamento & purificação , Humanos , Lactobacillus/química , Lactobacillus/crescimento & desenvolvimento , Lactobacillus plantarum/química , Lactobacillus plantarum/crescimento & desenvolvimento , Malásia , Probióticos/química , Probióticos/isolamento & purificação
18.
Org Biomol Chem ; 15(39): 8410-8417, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28952634

RESUMO

A simple and practical method for I2-mediated one-pot synthesis of 3-alkyl-5-aryl-1,2,4-thiadiazoles has been developed; the one-pot reaction includes sequential intermolecular addition of thioamides to nitriles, and intramolecular oxidative coupling of N-H and S-H bonds mediated by molecular iodine. Meanwhile the protocol uses readily available nitriles and thioamides as the starting materials, molecular iodine as the oxidant, and generates various 1,2,4-thiadiazoles in moderate to good yields with a wide array of functional groups. This method is an efficient approach for the synthesis of unsymmetrically disubstituted 1,2,4-thiadiazoles.

19.
BMC Genomics ; 17: 66, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26781612

RESUMO

BACKGROUND: Basal stem rot (BSR) is a fungal disease in oil palm (Elaeis guineensis Jacq.) which is caused by hemibiotrophic white rot fungi belonging to the Ganoderma genus. Molecular responses of oil palm to these pathogens are not well known although this information is crucial to strategize effective measures to eradicate BSR. In order to elucidate the molecular interactions between oil palm and G. boninense and its biocontrol fungus Trichoderma harzianum, we compared the root transcriptomes of untreated oil palm seedlings with those inoculated with G. boninense and T. harzianum, respectively. RESULTS: Differential gene expression analyses revealed that jasmonate (JA) and salicylate (SA) may act in an antagonistic manner in affecting the hormone biosynthesis, signaling, and downstream defense responses in G. boninense-treated oil palm roots. In addition, G. boninense may compete with the host to control disease symptom through the transcriptional regulation of ethylene (ET) biosynthesis, reactive oxygen species (ROS) production and scavenging. The strengthening of host cell walls and production of pathogenesis-related proteins as well as antifungal secondary metabolites in host plants, are among the important defense mechanisms deployed by oil palm against G. boninense. Meanwhile, endophytic T. harzianum was shown to improve the of nutrition status and nutrient transportation in host plants. CONCLUSION: The findings of this analysis have enhanced our understanding on the molecular interactions of G. boninense and oil palm, and also the biocontrol mechanisms involving T. harzianum, thus contributing to future formulations of better strategies for prevention and treatment of BSR.


Assuntos
Arecaceae/genética , Arecaceae/microbiologia , Interações Hospedeiro-Patógeno/genética , Trichoderma/fisiologia , Ciclopentanos/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salicilatos/metabolismo , Trichoderma/genética
20.
BMC Genomics ; 17: 91, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26842951

RESUMO

BACKGROUND: Ochroconis mirabilis, a recently introduced water-borne dematiaceous fungus, is occasionally isolated from human skin lesions and nails. We identified an isolate of O. mirabilis from a skin scraping with morphological and molecular studies. Its genome was then sequenced and analysed for genetic features related to classification and biological characteristics. RESULTS: UM 578 was identified as O. mirabilis based on morphology and internal transcribed spacer (ITS)-based phylogeny. The 34.61 Mb assembled genome with 13,435 predicted genes showed less efficiency of this isolate in plant cell wall degradation. Results from the peptidase comparison analysis with reported keratin-degrading peptidases from dermatophytes suggest that UM 578 is very unlikely to be utilising these peptidases to survive in the host. Nevertheless, we have identified peptidases from M10A, M12A and S33 families that may allow UM 578 to invade its host via extracellular matrix and collagen degradation. Furthermore, the lipases in UM 578 may have a role in supporting the fungus in host invasion. This fungus has the potential ability to synthesise melanin via the 1,8-dihydroxynaphthalene (DHN)-melanin pathway and to produce mycotoxins. The mating ability of this fungus was also inspected in this study and a mating type gene containing alpha domain was identified. This fungus is likely to produce taurine that is required in osmoregulation. The expanded gene family encoding the taurine catabolism dioxygenase TauD/TdfA domain suggests the utilisation of taurine under sulfate starvation. The expanded glutathione-S-transferase domains and RTA1-like protein families indicate the selection of genes in UM 578 towards adaptation in hostile environments. CONCLUSIONS: The genomic analysis of O. mirabilis UM 578 provides a better understanding of fungal survival tactics in different habitats.


Assuntos
Adaptação Biológica , Ascomicetos/classificação , Ascomicetos/genética , Genoma Fúngico , Adaptação Biológica/genética , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Metabolismo dos Carboidratos/genética , Biologia Computacional/métodos , Elementos de DNA Transponíveis , DNA Intergênico , Genes Fúngicos , Genômica , Mirabilis , Anotação de Sequência Molecular , Família Multigênica , Fenótipo , Filogenia , Metabolismo Secundário
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