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1.
Braz J Microbiol ; 54(3): 1351-1372, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37351789

ABSTRACT

Neoscytalidium dimidiatum and Bipolaris species are fungal plant pathogens that have been reported to cause human diseases. Recently, we have isolated numerous N. dimidiatum and Bipolaris species from the skin scrapings and nails of different patients. In this work, we have sequenced the genome of one strain of N. dimidiatum. The sequenced genome was compared to that of a previously reported Bipolaris papendorfii genome for a better understanding of their complex lifestyle and broad host-range pathogenicity. Both N. dimidiatum UM 880 (~ 43 Mb) and B. papendorfii UM 226 (~ 33 Mb) genomes include 11,015-12,320 putative coding DNA sequences, of which 0.51-2.49% are predicted transposable elements. Analysis of secondary metabolism gene clusters revealed several genes involved in melanin biosynthesis and iron uptake. The arsenal of CAZymes related to plants pathogenicity is comparable between the species, including genes involved in hemicellulose and pectin decomposition. Several important gene encoding keratinolytic peptidases were identified in N. dimidiatum and B. papendorfii, reflecting their potential pathogenic role in causing skin and nail infections. In this study, additional information on the metabolic features of these two species, such as nutritional profiling, pH tolerance, and osmotolerant, are revealed. The genomic characterization of N. dimidiatum and B. papendorfii provides the basis for the future functional studies to gain further insights as to what makes these fungi persist in plants and why they are pathogenic to humans.


Subject(s)
Ascomycota , Humans , Ascomycota/genetics , Curvularia , Genomics , Bipolaris
2.
J Food Sci Technol ; 59(9): 3379-3386, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35875243

ABSTRACT

This study investigated growth characteristics and antibacterial properties of probiotics in fermented coconut milk (CM) against Streptococcus pyogenes. A total of eight probiotics were screened for their survivability in CM. Antibacterial test against S. pyogenes was carried out on strain with highest growth rate. The survivability of probiotics in CM is strain dependent with S. salivarius ATCC 13419 showing the highest growth rate. Titratable acidity of the CM increased significantly while pH decreased significantly upon 9 h fermentation. The antibacterial properties of CM fermented with S. salivarius ATCC 13419 and K12 against S. pyogenes enhanced by 60.60% and 67.69%, respectively, compared to non-fermented CM. Their ability to metabolise carbohydrates and fats in CM was proven where alpha-glucosidase activity of S. salivarius ATCC 13419 and K12 was 22.42 ± 1.73 and 24.92 ± 7.22 unit/L, respectively, whereas, lipase activity was 1498.29 ± 48.50 and 1749.90 ± 254.28 unit/L, respectively. Lipolytic activity of these strains was further evidenced by GC-MS results whereby lauric acid content (potent antibacterial substance) in CM fermented with S. salivarius ATCC 13419 and K12 increased significantly by 5.03% and 10.74%, respectively. In conclusion, fermented CM provided a new alternative of non-dairy functional product with antibacterial potential against S. pyogenes.

3.
J Thorac Dis ; 11(11): 4626-4633, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31903251

ABSTRACT

BACKGROUND: In many developing countries, acute respiratory tract infections (ARTIs) are the main cause of morbidity and mortality among young children. This study aims to evaluate the molecular epidemiology of respiratory viruses among Malaysian children with confirmed respiratory infections between July 2014 and July 2015. METHODS: A total of 394 nasopharyngeal swabs were collected prospectively from children age 0-5 years old with ARTIs from hospitals in Kuala Lumpur. Respiratory viral panel (RVP) assay was used to identify the viral aetiology of respiratory infections. RESULTS: From a total of 394 samples, the positive detection rate was 79.9% (n=315). A total of 15 types of RNA viruses and a single type of DNA virus were detected. Enterovirus/rhinovirus (n=112, 28.4%), respiratory syncytial virus (RSV) (n=85, 21.6%), adenovirus (n=64, 16.2%), human bocavirus (n=34, 8.6%), and human metapneumovirus (n=29, 7.4%) were the five predominant viruses. Enterovirus/rhinovirus and RSV constituted most of the viral respiratory infections among young children, especially among children less than 1 year old. No coronavirus was detected among children between 3 and 5 years old. Co-infection caused by 2 or 3 respiratory viruses were detected in 52 patients (13.2%). Enterovirus/rhinovirus, adenovirus, and human bocavirus demonstrated pronounced seasonality. The infection rate peaked during mid-year, while the lowest activity occurred during early of the year. CONCLUSIONS: The use of molecular assay as a routine diagnostic in the hospitals can improve the diagnosis and management of respiratory tract infections among children.

4.
Front Microbiol ; 8: 1433, 2017.
Article in English | MEDLINE | ID: mdl-28824567

ABSTRACT

Given the remarkable increase of public interest in organic food products, it is indeed critical to evaluate the microbiological risk associated with consumption of fresh organic produce. Organic farming practices including the use of animal manures may increase the risk of microbiological contamination as manure can act as a vehicle for transmission of foodborne pathogens. This study aimed to determine and compare the microbiological status between organic and conventional fresh produce at the retail level in Malaysia. A total of 152 organic and conventional vegetables were purchased at retail markets in Malaysia. Samples were analyzed for mesophilic aerobic bacteria, yeasts and molds, and total coliforms using conventional microbiological methods. Combination methods of most probable number-multiplex polymerase chain reaction (MPN-mPCR) were used to detect and quantify foodborne pathogens, including Escherichia coli O157:H7, Shiga toxin-producing E. coli (STEC), Listeria monocytogenes, Salmonella Typhimurium, and Salmonella Enteritidis. Results indicated that most types of organic and conventional vegetables possessed similar microbial count (P > 0.05) of mesophilic aerobic bacteria, yeasts and molds, and total coliforms. E. coli O157:H7 and S. Typhimurium were not detected in any sample analyzed in this study. Among the 152 samples tested, only the conventional lettuce and organic carrot were tested positive for STEC and S. Enteritidis, respectively. L. monocytogenes were more frequently detected in both organic (9.1%) and conventional vegetables (2.7%) as compared to E. coli O157:H7, S. Typhimurium, and S. Enteritidis. Overall, no trend was shown that either organically or conventionally grown vegetables have posed greater microbiological risks. These findings indicated that one particular type of farming practices would not affect the microbiological profiles of fresh produce. Therefore, regardless of farming methods, all vegetables should be subjected to appropriate post-harvest handling practices from farm to fork to ensure the quality and safety of the fresh produce.

5.
PeerJ ; 5: e2841, 2017.
Article in English | MEDLINE | ID: mdl-28149676

ABSTRACT

Corynespora cassiicola is a common plant pathogen that causes leaf spot disease in a broad range of crop, and it heavily affect rubber trees in Malaysia (Hsueh, 2011; Nghia et al., 2008). The isolation of UM 591 from a patient's contact lens indicates the pathogenic potential of this dematiaceous fungus in human. However, the underlying factors that contribute to the opportunistic cross-infection have not been fully studied. We employed genome sequencing and gene homology annotations in attempt to identify these factors in UM 591 using data obtained from publicly available bioinformatics databases. The assembly size of UM 591 genome is 41.8 Mbp, and a total of 13,531 (≥99 bp) genes have been predicted. UM 591 is enriched with genes that encode for glycoside hydrolases, carbohydrate esterases, auxiliary activity enzymes and cell wall degrading enzymes. Virulent genes comprising of CAZymes, peptidases, and hypervirulence-associated cutinases were found to be present in the fungal genome. Comparative analysis result shows that UM 591 possesses higher number of carbohydrate esterases family 10 (CE10) CAZymes compared to other species of fungi in this study, and these enzymes hydrolyses wide range of carbohydrate and non-carbohydrate substrates. Putative melanin, siderophore, ent-kaurene, and lycopene biosynthesis gene clusters are predicted, and these gene clusters denote that UM 591 are capable of protecting itself from the UV and chemical stresses, allowing it to adapt to different environment. Putative sterigmatocystin, HC-toxin, cercosporin, and gliotoxin biosynthesis gene cluster are predicted. This finding have highlighted the necrotrophic and invasive nature of UM 591.

6.
Malays J Med Sci ; 24(5): 33-43, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29386970

ABSTRACT

INTRODUCTION: Acute respiratory tract infections (ARTIs) are a major cause of morbidity and mortality in paediatric patients. Therefore, early detection of the viral aetiologies of ARTIs is essential for patient management and infection control. In this study, we evaluated the performance of a new multiplex polymerase chain reaction (PCR) assay (xTAG Respiratory Viral Panel [RVP] Fast v2) in the detection of respiratory viruses by comparing it with that of viral culture and direct immunofluorescence (IF) staining. METHODS: Nasopharyngeal swab and aspirate samples were collected prospectively from 199 patients who presented with ARTIs at the University Malaya Medical Centre (UMMC) in Kuala Lumpur, Malaysia during a 10-month period. The PCR assay was conducted in parallel with conventional culture and direct IF staining methods. RESULTS: The positive rate of the xTAG RVP Fast v2 assay (78.4%) in detecting respiratory viruses was higher than that of the viral isolation (7.5%) and direct IF (23.1%) methods. Using the xTAG RVP Fast v2 assay, human enterovirus/human rhinovirus (HEV/HRV) was the most frequently detected (46.2%). The xTAG RVP Fast v2 assay revealed mixed infection caused by two or three respiratory viruses in 40 specimens, and these were undetected by the viral isolation and direct IF methods. CONCLUSION: The xTAG RVP Fast v2 assay was superior to conventional methods in the identification of common respiratory viruses, with higher sensitivity and shorter turnaround times for laboratory results.

7.
PeerJ ; 4: e2637, 2016.
Article in English | MEDLINE | ID: mdl-28028453

ABSTRACT

BACKGROUND: Daldinia eschscholtzii is a filamentous wood-inhabiting endophyte commonly found in woody plants. Here, we report the identification and characterization of nine D. eschscholtzii isolates from skin scrapings, nail clippings, and blood. METHODS: The nine isolates were identified based on colony morphology, light microscopy, and internal transcribed spacer (ITS)-based phylogeny. In vitro antifungal susceptibility of the fungal isolates was evaluated by the Etest to determine the minimum inhibitory concentration (MIC). RESULTS: The nine isolates examined were confirmed as D. eschscholtzii. They exhibited typical features of Daldinia sp. on Sabouraud Dextrose Agar, with white felty colonies and black-gray coloration on the reverse side. Septate hyphae, branching conidiophore with conidiogenous cells budding from its terminus, and nodulisporium-like conidiophores were observed under the microscope. Phylogenetic analysis revealed that the nine isolates were clustered within the D. eschscholtzii species complex. All the isolates exhibited low MICs against azole agents (voriconazole, posaconazole, itraconazole, and ketoconazole), as well as amphotericin B, with MIC of less than 1 µg/ml. DISCUSSION: Early and definitive identification of D. eschscholtzii is vital to reducing misuse of antimicrobial agents. Detailed morphological and molecular characterization as well as antifungal profiling of D. eschscholtzii provide the basis for future studies on its biology, pathogenicity, and medicinal potential.

8.
PLoS One ; 11(9): e0162095, 2016.
Article in English | MEDLINE | ID: mdl-27626635

ABSTRACT

Pyrenochaeta unguis-hominis is a rare human pathogen that causes infection in human skin and nail. P. unguis-hominis has received little attention, and thus, the basic biology and pathogenicity of this fungus is not fully understood. In this study, we performed in-depth analysis of the P. unguis-hominis UM 256 genome that was isolated from the skin scraping of a dermatitis patient. The isolate was identified to species level using a comprehensive multilocus phylogenetic analysis of the genus Pyrenochaeta. The assembled UM 256 genome has a size of 35.5 Mb and encodes 12,545 putative genes, and 0.34% of the assembled genome is predicted transposable elements. Its genomic features propose that the fungus is a heterothallic fungus that encodes a wide array of plant cell wall degrading enzymes, peptidases, and secondary metabolite biosynthetic enzymes. Antifungal drug resistance genes including MDR, CDR, and ERG11/CYP51 were identified in P. unguis-hominis UM 256, which may confer resistance to this fungus. The genome analysis of P. unguis-hominis provides an insight into molecular and genetic basis of the fungal lifestyles, understanding the unrevealed biology of antifungal resistance in this fungus.


Subject(s)
Ascomycota/genetics , Dermatomycoses/microbiology , Genome, Fungal/genetics , Antifungal Agents/pharmacology , Ascomycota/drug effects , Ascomycota/metabolism , DNA Transposable Elements/genetics , Drug Resistance, Multiple, Fungal , Genes, Fungal/genetics , Humans , Multilocus Sequence Typing , Phylogeny , Skin/microbiology
9.
PLoS One ; 11(8): e0161008, 2016.
Article in English | MEDLINE | ID: mdl-27570972

ABSTRACT

Cladophialophora bantiana is a dematiaceous fungus with a predilection for causing central nervous system (CNS) infection manifesting as brain abscess in both immunocompetent and immunocompromised patients. In this paper, we report comprehensive genomic analyses of C. bantiana isolated from the brain abscess of an immunocompetent man, the first reported case in Malaysia and Southeast Asia. The identity of the fungus was determined using combined morphological analysis and multilocus phylogeny. The draft genome sequence of a neurotrophic fungus, C. bantiana UM 956 was generated using Illumina sequencing technology to dissect its genetic fundamental and basic biology. The assembled 37.1 Mb genome encodes 12,155 putative coding genes, of which, 1.01% are predicted transposable elements. Its genomic features support its saprophytic lifestyle, renowned for its versatility in decomposing hemicellulose and pectin components. The C. bantiana UM 956 was also found to carry some important putative genes that engaged in pathogenicity, iron uptake and homeostasis as well as adaptation to various stresses to enable the organism to survive in hostile microenvironment. This wealth of resource will further catalyse more downstream functional studies to provide better understanding on how this fungus can be a successful and persistent pathogen in human.


Subject(s)
Ascomycota/pathogenicity , Cerebral Phaeohyphomycosis/diagnosis , Cerebral Phaeohyphomycosis/microbiology , Animals , Ascomycota/classification , Ascomycota/genetics , Brain Abscess/microbiology , Central Nervous System Fungal Infections/microbiology , Cerebral Phaeohyphomycosis/metabolism , Genome, Fungal/genetics , Genomics , Humans , Male , Middle Aged , Phylogeny , Virulence/genetics , Virulence/physiology
10.
PLoS One ; 11(6): e0156119, 2016.
Article in English | MEDLINE | ID: mdl-27280438

ABSTRACT

A yeast-like organism was isolated from the skin scraping sample of a stasis dermatitis patient in the Mycology Unit Department of Medical Microbiology, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia. The isolate produced no pigment and was not identifiable using chromogenic agar and API 20C AUX. The fungus was identified as Metschnikowia sp. strain UM 1034, which is close to that of Metschnikowia drosophilae based on ITS- and D1/D2 domain-based phylogenetic analysis. However, the physiology of the strain was not associated to M. drosophilae. This pathogen exhibited low sensitivity to all tested azoles, echinocandins, 5-flucytosine and amphotericin B. This study provided insight into Metschnikowia sp. strain UM 1034 phenotype profiles using a Biolog phenotypic microarray (PM). The isolate utilized 373 nutrients of 760 nutrient sources and could adapt to a broad range of osmotic and pH environments. To our knowledge, this is the first report of the isolation of Metschnikowia non-pulcherrima sp. from skin scraping, revealing this rare yeast species as a potential human pathogen that may be misidentified as Candida sp. using conventional methods. Metschnikowia sp. strain UM 1034 can survive in flexible and diverse environments with a generalist lifestyle.


Subject(s)
Dermatitis/microbiology , Metschnikowia/isolation & purification , Metschnikowia/pathogenicity , Mycoses/microbiology , Skin/microbiology , Aged , Antifungal Agents/pharmacology , DNA, Fungal/genetics , DNA, Ribosomal/genetics , Humans , Male , Metschnikowia/classification , Metschnikowia/drug effects , Mycological Typing Techniques , Mycoses/complications , Mycoses/genetics , Phylogeny , Pigmentation , Sequence Analysis, DNA , Skin/drug effects , Skin/metabolism
11.
Sci Rep ; 6: 27008, 2016 05 31.
Article in English | MEDLINE | ID: mdl-27243961

ABSTRACT

Cladosporium sphaerospermum, a dematiaceous saprophytic fungus commonly found in diverse environments, has been reported to cause allergy and other occasional diseases in humans. However, its basic biology and genetic information are largely unexplored. A clinical isolate C. sphaerospermum genome, UM 843, was re-sequenced and combined with previously generated sequences to form a model 26.89 Mb genome containing 9,652 predicted genes. Functional annotation on predicted genes suggests the ability of this fungus to degrade carbohydrate and protein complexes. Several putative peptidases responsible for lung tissue hydrolysis were identified. These genes shared high similarity with the Aspergillus peptidases. The UM 843 genome encodes a wide array of proteins involved in the biosynthesis of melanin, siderophores, cladosins and survival in high salinity environment. In addition, a total of 28 genes were predicted to be associated with allergy. Orthologous gene analysis together with 22 other Dothideomycetes showed genes uniquely present in UM 843 that encode four class 1 hydrophobins which may be allergens specific to Cladosporium. The mRNA of these hydrophobins were detected by RT-PCR. The genomic analysis of UM 843 contributes to the understanding of the biology and allergenicity of this widely-prevalent species.


Subject(s)
Allergens/genetics , Cladosporium/genetics , Fungal Proteins/genetics , Genome, Fungal , Hypersensitivity/immunology , Peptide Hydrolases/genetics , Adaptation, Physiological , Allergens/immunology , Aspergillus/genetics , Aspergillus/immunology , Cladosporium/classification , Cladosporium/immunology , Fungal Proteins/immunology , Gene Expression , Gene Ontology , Humans , Hypersensitivity/genetics , Hypersensitivity/microbiology , Lung/immunology , Lung/microbiology , Melanins/genetics , Melanins/immunology , Molecular Sequence Annotation , Mycoses/immunology , Mycoses/microbiology , Peptide Hydrolases/immunology , Phylogeny , Polyketides/chemistry , Polyketides/immunology , Siderophores/chemistry , Siderophores/immunology
12.
Article in English | MEDLINE | ID: mdl-26980516

ABSTRACT

Many species of dematiaceous fungi are associated with allergic reactions and potentially fatal diseases in human, especially in tropical climates. Over the past 10 years, we have isolated more than 400 dematiaceous fungi from various clinical samples. In this study, DemaDb, an integrated database was designed to support the integration and analysis of dematiaceous fungal genomes. A total of 92 072 putative genes and 6527 pathways that identified in eight dematiaceous fungi (Bipolaris papendorfii UM 226, Daldinia eschscholtzii UM 1400, D. eschscholtzii UM 1020, Pyrenochaeta unguis-hominis UM 256, Ochroconis mirabilis UM 578, Cladosporium sphaerospermum UM 843, Herpotrichiellaceae sp. UM 238 and Pleosporales sp. UM 1110) were deposited in DemaDb. DemaDb includes functional annotations for all predicted gene models in all genomes, such as Gene Ontology, EuKaryotic Orthologous Groups, Kyoto Encyclopedia of Genes and Genomes (KEGG), Pfam and InterProScan. All predicted protein models were further functionally annotated to Carbohydrate-Active enzymes, peptidases, secondary metabolites and virulence factors. DemaDb Genome Browser enables users to browse and visualize entire genomes with annotation data including gene prediction, structure, orientation and custom feature tracks. The Pathway Browser based on the KEGG pathway database allows users to look into molecular interaction and reaction networks for all KEGG annotated genes. The availability of downloadable files containing assembly, nucleic acid, as well as protein data allows the direct retrieval for further downstream works. DemaDb is a useful resource for fungal research community especially those involved in genome-scale analysis, functional genomics, genetics and disease studies of dematiaceous fungi. Database URL: http://fungaldb.um.edu.my.


Subject(s)
Databases, Genetic , Genome, Fungal , Genes, Fungal , Humans , Internet , Models, Genetic , Molecular Sequence Annotation
13.
BMC Genomics ; 17: 91, 2016 Feb 03.
Article in English | MEDLINE | ID: mdl-26842951

ABSTRACT

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.


Subject(s)
Adaptation, Biological , Ascomycota/classification , Ascomycota/genetics , Genome, Fungal , Adaptation, Biological/genetics , Ascomycota/growth & development , Ascomycota/metabolism , Carbohydrate Metabolism/genetics , Computational Biology/methods , DNA Transposable Elements , DNA, Intergenic , Genes, Fungal , Genomics , Mirabilis , Molecular Sequence Annotation , Multigene Family , Phenotype , Phylogeny , Secondary Metabolism
14.
PLoS One ; 11(1): e0147886, 2016.
Article in English | MEDLINE | ID: mdl-26807725

ABSTRACT

BACKGROUND: Ethanolamine kinase (EK) catalyzes the phosphorylation of ethanolamine, the first step in the CDP-ethanolamine pathway for the biosynthesis of phosphatidylethanolamine (PE). Human EK exists as EK1, EK2α and EK2ß isoforms, encoded by two separate genes, named ek1 and ek2. EK activity is stimulated by carcinogens and oncogenes, suggesting the involvement of EK in carcinogenesis. Currently, little is known about EK transcriptional regulation by endogenous or exogenous signals, and the ek gene promoter has never been studied. METHODOLOGY/PRINCIPAL FINDINGS: In this report, we mapped the important regulatory regions in the human ek1 promoter. 5' deletion analysis and site-directed mutagenesis identified a Sp site at position (-40/-31) that was essential for the basal transcription of this gene. Treatment of HCT116 cells with trichostatin A (TSA), a histone deacetylase inhibitor, significantly upregulated the ek1 promoter activity through the Sp(-40/-31) site and increased the endogenous expression of ek1. Chromatin immunoprecipitation assay revealed that TSA increased the binding of Sp1, Sp3 and RNA polymerase II to the ek1 promoter in HCT116 cells. The effect of TSA on ek1 promoter activity was cell-line specific as TSA treatment did not affect ek1 promoter activity in HepG2 cells. CONCLUSION/SIGNIFICANCE: In conclusion, we showed that Sp1 and Sp3 are not only essential for the basal transcription of the ek1 gene, their accessibility to the target site on the ek1 promoter is regulated by histone protein modification in a cell line dependent manner.


Subject(s)
Carcinoma/metabolism , Colonic Neoplasms/metabolism , Hydroxamic Acids/pharmacology , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Sp1 Transcription Factor/metabolism , Sp3 Transcription Factor/metabolism , Cell Line, Tumor , Histone Deacetylase Inhibitors/pharmacology , Humans , Phosphotransferases (Alcohol Group Acceptor)/genetics , Promoter Regions, Genetic/drug effects , Transcriptional Activation/drug effects
15.
PLoS One ; 10(12): e0145932, 2015.
Article in English | MEDLINE | ID: mdl-26716988

ABSTRACT

Peritonitis is the leading complication of peritoneal dialysis, which is primarily caused by bacteria rather than fungi. Peritonitis is responsible for approximately 18% of the infection-related mortality in peritoneal dialysis patients. In this paper, we report the isolation of a rare fungus, Quambalaria cyanescens, from the peritoneal fluid of a man after he switched from continuous ambulatory peritoneal dialysis to nocturnal intermittent peritoneal dialysis. Based on the morphological examination and multigene phylogeny, the clinical isolate was confirmed as Q. cyanescens. This pathogen exhibited low sensitivity to all tested echinocandins and 5-flucytosine. Interestingly, morphological characterization revealed that Q. cyanescens UM 1095 produced different pigments at low temperatures (25°C and 30°C) on various culture media. It is important to monitor the emergence of this rare fungus as a potential human pathogen in the tropics. This study provides insight into Q. cyanescens UM 1095 phenotype profiles using a Biolog phenotypic microarray (PM). Of the 760 nutrient sources tested, Q. cyanescens UM 1095 utilized 42 compounds, and the fungus can adapt to a broad range of osmotic and acidic environments. To our knowledge, this is the first report of the isolation of Q. cyanescens from peritoneal fluid, revealing this rare fungus as a potential human pathogen that may be misidentified using conventional methods. The detailed morphological, molecular and phenotypic characterization of Q. cyanescens UM 1095 provides the basis for future studies on its biology, lifestyle, and potential pathogenicity.


Subject(s)
Ascitic Fluid/microbiology , Basidiomycota/isolation & purification , Basidiomycota/pathogenicity , Mycoses/microbiology , Peritoneal Dialysis/adverse effects , Peritonitis/microbiology , Basidiomycota/classification , DNA, Fungal/genetics , Drug Resistance, Fungal , Humans , Male , Metabolome , Middle Aged , Mycological Typing Techniques , Phylogeny
16.
Trop Med Int Health ; 20(11): 1447-1453, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26216479

ABSTRACT

OBJECTIVE: To describe a prospective laboratory-based surveillance of Candida species that were collected from different anatomical sites of patients admitted to the University of Malaya Medical Centre, Malaysia, from the year 2000 to 2013. METHODS: Conventional (culture, microscopic examination and carbohydrate assimilation test) and molecular (PCR amplification and DNA sequencing) techniques were used to identify Candida species. RESULTS: A total of 16 Candida species isolated from 34 392 clinical samples were from the oral cavity (oral swabs and throat swabs), blood, respiratory tract (sputum, tracheal secretions, nasopharyngeal aspirates, bronchoalveolar lavage), high vaginal swab, pus and urine. C. albicans (66.70%, 22 941/34 392), C. glabrata (11.71%, 4029/34 392), C. parapsilopsis (10.74%, 3692/34 392), C. tropicalis (9.19%, 3162/34 392) and C. krusei (1.15%, 396/34 392) were the five predominant Candida species. C. albicans was the predominant species isolated from the oral cavity, respiratory tract and high vaginal swab; while the Candida species isolated from blood, urine and pus were predominant non-albicans Candida. Uncommon Candida species, such as C. lusitaniae, C. haemulonii, C. humicola, Pichia ohmeri and C. ciferrii, were also isolated in this study. CONCLUSION: Our study expands the current knowledge of the epidemiology of non-invasive and invasive candidiasis in Malaysia. The variability of the Candida species distribution from different anatomical sites highlights the significance of local epidemiology in disease management and selection of antifungal agents.

17.
PLoS One ; 10(6): e0131694, 2015.
Article in English | MEDLINE | ID: mdl-26110649

ABSTRACT

The outbreak of extensively drug-resistant tuberculosis (XDR-TB) has become an increasing problem in many TB-burdened countries. The underlying drug resistance mechanisms, including the genetic variation favored by selective pressure in the resistant population, are partially understood. Recently, the first case of XDR-TB was reported in Malaysia. However, the detailed genotype family and mechanisms of the formation of multiple drugs resistance are unknown. We sequenced the whole genome of the UM 1072388579 strain with a 2-kb insert-size library and combined with that from previously sequenced 500-bp-insert paired-end reads to produce an improved sequence with maximal sequencing coverage across the genome. In silico spoligotyping and phylogenetic analyses demonstrated that UM 1072388579 strain belongs to an ancestral-like, non-Beijing clade of East Asia lineage. This is supported by the presence of a number of lineage-specific markers, including fadD28, embA, nuoD and pks7. Polymorphism analysis showed that the drug-susceptibility profile is correlated with the pattern of resistance mutations. Mutations in drug-efflux pumps and the cell wall biogenesis pathway such as mmpL, pks and fadD genes may play an important role in survival and adaptation of this strain to its surrounding environment. In this work, fifty-seven putative promoter SNPs were identified. Among them, we identified a novel SNP located at -4 T allele of TetR/acrR promoter as an informative marker to recognize strains of East Asian lineage. Our work indicates that the UM 1072388579 harbors both classical and uncommon SNPs that allow it to escape from inhibition by many antibiotics. This study provides a strong foundation to dissect the biology and underlying resistance mechanisms of the first reported XDR M. tuberculosis in Malaysia.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Extensively Drug-Resistant Tuberculosis/microbiology , Mycobacterium tuberculosis/genetics , Antitubercular Agents/therapeutic use , Extensively Drug-Resistant Tuberculosis/genetics , Gene Expression Profiling , Genome, Bacterial , Humans , Malaysia , Male , Microbial Sensitivity Tests , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Mycobacterium tuberculosis/pathogenicity , Phylogeny , Polymorphism, Single Nucleotide
18.
DNA Res ; 22(3): 219-32, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25922537

ABSTRACT

Bipolaris papendorfii has been reported as a fungal plant pathogen that rarely causes opportunistic infection in humans. Secondary metabolites isolated from this fungus possess medicinal and anticancer properties. However, its genetic fundamental and basic biology are largely unknown. In this study, we report the first draft genome sequence of B. papendorfii UM 226 isolated from the skin scraping of a patient. The assembled 33.4 Mb genome encodes 11,015 putative coding DNA sequences, of which, 2.49% are predicted transposable elements. Multilocus phylogenetic and phylogenomic analyses showed B. papendorfii UM 226 clustering with Curvularia species, apart from other plant pathogenic Bipolaris species. Its genomic features suggest that it is a heterothallic fungus with a putative unique gene encoding the LysM-containing protein which might be involved in fungal virulence on host plants, as well as a wide array of enzymes involved in carbohydrate metabolism, degradation of polysaccharides and lignin in the plant cell wall, secondary metabolite biosynthesis (including dimethylallyl tryptophan synthase, non-ribosomal peptide synthetase, polyketide synthase), the terpenoid pathway and the caffeine metabolism. This first genomic characterization of B. papendorfii provides the basis for further studies on its biology, pathogenicity and medicinal potential.


Subject(s)
Ascomycota/physiology , Genome, Fungal , Ascomycota/genetics , DNA Transposable Elements , Genomics , Phylogeny , Secondary Metabolism/genetics
19.
PLoS One ; 9(12): e113485, 2014.
Article in English | MEDLINE | ID: mdl-25490397

ABSTRACT

BACKGROUND: Choline kinase is the most upstream enzyme in the CDP-choline pathway. It catalyzes the phosphorylation of choline to phosphorylcholine in the presence of ATP and Mg2+ during the biosynthesis of phosphatidylcholine, the major phospholipid in eukaryotic cell membranes. In humans, choline kinase (CK) is encoded by two separate genes, ckα and ckß, which produce three isoforms, CKα1, CKα2, and CKß. Previous studies have associated ckß with muscle development; however, the molecular mechanism underlying the transcriptional regulation of ckß has never been elucidated. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the distal promoter region of the ckß gene was characterized. Mutational analysis of the promoter sequence and electrophoretic mobility shift assays (EMSA) showed that Ets and GATA transcription factors were essential for the repression of ckß promoter activity. Supershift and chromatin immunoprecipitation (ChIP) assays further identified that GATA3 but not GATA2 was bound to the GATA site of ckß promoter. In addition, phorbol-12-myristate-13-acetate (PMA) decreased ckß promoter activity through Ets and GATA elements. PMA also decreased the ckß mRNA and protein levels about 12 hours after the promoter activity was down-regulated. EMSA further revealed that PMA treatment increased the binding of both Ets and GATA transcription factors to their respective DNA elements. The PMA-mediated repressive effect was abolished by chronic PMA treatment and by treatment with the PKC inhibitor PKC412, but not the PKC inhibitor Go 6983, suggesting PKCε or PKCη as the PKC isozyme involved in the PMA-mediated repression of ckß promoter. Further confirmation by using PKC isozyme specific inhibitors identified PKCε as the isozyme that mediated the PMA repression of ckß promoter. CONCLUSION/SIGNIFICANCE: These results demonstrate the participation of the PKC signaling pathway in the regulation of ckß gene transcription by Ets and GATA transcription factors.


Subject(s)
Choline Kinase/genetics , GATA Transcription Factors/metabolism , Promoter Regions, Genetic/genetics , Protein Kinase C/metabolism , Proto-Oncogene Protein c-ets-1/metabolism , Signal Transduction/drug effects , Tetradecanoylphorbol Acetate/pharmacology , Base Sequence , Cell Line, Tumor , CpG Islands/genetics , Humans , Molecular Sequence Data , Mutation , Promoter Regions, Genetic/drug effects , Protein Kinase Inhibitors/pharmacology , Staurosporine/analogs & derivatives , Staurosporine/pharmacology
20.
Int J Mol Sci ; 13(1): 901-917, 2012.
Article in English | MEDLINE | ID: mdl-22312293

ABSTRACT

Klebsiella pneumoniae is a Gram-negative, cylindrical rod shaped opportunistic pathogen that is found in the environment as well as existing as a normal flora in mammalian mucosal surfaces such as the mouth, skin, and intestines. Clinically it is the most important member of the family of Enterobacteriaceae that causes neonatal sepsis and nosocomial infections. In this work, a combination of protein sequence analysis, structural modeling and molecular docking simulation approaches were employed to provide an understanding of the possible functions and characteristics of a hypothetical protein (KPN_02809) from K. pneumoniae MGH 78578. The computational analyses showed that this protein was a metalloprotease with zinc binding motif, HEXXH. To verify this result, a ypfJ gene which encodes for this hypothetical protein was cloned from K. pneumoniae MGH 78578 and the protein was overexpressed in Escherichia coli BL21 (DE3). The purified protein was about 32 kDa and showed maximum protease activity at 30 °C and pH 8.0. The enzyme activity was inhibited by metalloprotease inhibitors such as EDTA, 1,10-phenanthroline and reducing agent, 1,4-dithiothreitol (DTT). Each molecule of KPN_02809 protein was also shown to bind one zinc ion. Hence, for the first time, we experimentally confirmed that KPN_02809 is an active enzyme with zinc metalloprotease activity.


Subject(s)
Klebsiella pneumoniae/enzymology , Metalloproteases/metabolism , Amino Acid Sequence , Binding Sites , Cloning, Molecular , Escherichia coli/metabolism , Hydrogen-Ion Concentration , Metalloproteases/chemistry , Metalloproteases/genetics , Molecular Docking Simulation , Molecular Sequence Data , Phenanthrolines/chemistry , Phenanthrolines/metabolism , Protein Structure, Tertiary , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Temperature , Zinc/chemistry
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