MyMedR

Displaying publications 21 - 31 of 31 in total

Abstract:

Sort:

Fulltext Interaction between Metarhizium anisopliae and Its Host, the Subterranean Termite Coptotermes curvignathus during the Infection Process

Syazwan SA, Lee SY, Sajap AS, Lau WH, Omar D, Mohamed R

Biology (Basel), 2021 Mar 25;10(4).
PMID: 33806225 DOI: 10.3390/biology10040263

Metarhizium anisopliae (Metchnikoff) Sorokin, a pathogenic fungus to insects, infects the subterranean termite, Coptotermes curvignathus Holmgren, a devastating pest of plantation trees in the tropics. Electron microscopy and proteomics were used to investigate the infection and developmental process of M. anisopliae in C. curvignathus. Fungal infection was initiated by germ tube penetration through the host's cuticle as observed at 6 h post-inoculation (PI), after which it elongated into the host's integumental tissue. The colonization process continued as seen from dissemination of blastospores in the hemocoel at 96 h PI. At this time point, the emergent mycelia had mummified the host and forty-eight hours later, new conidia were dispersed on the termites' body surface. Meanwhile, hyphal bodies were observed in abundance in the intercellular space in the host's body. The proteomes of the pathogen and host were isolated separately using inoculated termite samples withdrawn at each PI-time point and analyzed in two-dimensional electrophoresis (2-DE) gels. Proteins expressed in termites showed evidence of being related to cell regulation and the immune response, while those expressed in M. anisopliae, to transportation and fungal virulence. This study provides new information on the interaction between termites and its entomopathogen, with potential utilization for developing future biopesticide to control the termite population.

Matched MeSH terms: Hyphae
Leucoxenols A and B, two new phenolics from Bornean medicinal plant Syzygium leucoxylon

Shamsudin KJ, Phan CS, Kulip J, Hatai K, Vairappan CS, Kamada T

J Asian Nat Prod Res, 2019 May;21(5):435-441.
PMID: 29502443 DOI: 10.1080/10286020.2018.1440391

The medicinal plant, Syzygium leucoxylon or commonly known as Obah found in North Borneo was considered as traditional medicine by local committee. Two new phenolics, leucoxenols A (1) and B (2) were isolated and identified as major secondary metabolites from the leaves of S. leucoxylon. Their chemical structures were elucidated based on spectroscopic data such as NMR and HRESIMS. Furthermore, these compounds were active against selected strains of fungi.

Matched MeSH terms: Hyphae/drug effects
Nicotine enhances the thickness of biofilm and adherence of Candida albicans ATCC 14053 and Candida parapsilosis ATCC 22019

Gunasegar S, Himratul-Aznita WH

FEMS Yeast Res., 2019 Mar 01;19(2).
PMID: 30476044 DOI: 10.1093/femsyr/foy123

Candida albicans ATCC 14053 and Candida parapsilosis ATCC 22019 hyphal-wall protein 1 (HWP1) are involved in hyphae formation and pathogenesis. The transcriptional agglutinin-like sequence 3 (ALS3) genes in both species are responsible for the development of biofilm and colonization on tooth surfaces. Therefore, we investigated the expression of HWP1 and ALS3 quantitatively in C. albicans and C. parapsilosis and examined the biofilm structure upon exposure to various nicotine concentrations. In vitro, biofilms of Candida species were developed directly on slides using the Lab-Tek Chamber Slide System and visualized by confocal laser scanning microscopy. Quantitative real-time polymerase chain reaction was used to measure HWP1 and ALS3 expression in C. albicans ATCC 14053 and C. parapsilosis ATCC 22019. The results indicated that nicotine multiplied the number of yeast cells and increased the extracellular polysaccharides of Candida species. We also found that 1-2 mg/mL nicotine could enhance the formation of biofilm. The findings also revealed that the expression of HWP1 and ALS3 in Candida species were increased as the nicotine concentration increased. Therefore, nicotine influences the biofilm development of oral-associated C. albicans ATCC 14053 and C. parapsilosis ATCC 22019.

Matched MeSH terms: Hyphae
Occupational risk assessment: review of wooden scaffold board application in Malaysian oil and gas industry

Mohd Jamil Abdul Wahab, Noor Azrieda Abd Rashid, Salmiah Ujang, Choon LS

Sains Malaysiana, 2016;45:1139-1147.

Timber scaffold boards have been widely utilised in the offshore construction industry. However, technical specifications
and inspection procedure for the application of scaffold boards from a wood material were inadequate. In the development
of the standard requirements, evaluation of actual engineering practices could indicate the level of workplace safety. A
study was conducted to identify risk and safety measures concerning the use of timber scaffold boards in construction.
This article discusses on the occupational risks and ergonomics issues of the scaffolding application based on the physical
and mechanical conditions of tropical timber scaffold boards extracted from offshore oil and gas rigs. The boards were
exposed to a seasonal climate of East Coast monsoon of South China Sea between November and February. The scaffolding
application extended up to 20 m directly above the ocean surface and some boards were completely immersed below
the ocean surface particularly during elevated tidal waves. Some of the boards were installed as the on-deck platforms.
Forty scaffold boards fabricated from tropical timber species were evaluated. Physical characteristics of the boards
were described by natural and man-made factors. A three-point bending test was conducted to determine the maximum
load capacity of each board and the mode of fracture was evaluated. Timber identification test was conducted to identify
the groups of the timber being used. The microscopic observation confirmed the presence of hyphae which indicated the
biological deterioration has happened in some of the boards. Occupational risks were summarised based on the results
of the physical and mechanical assessments

Matched MeSH terms: Hyphae
Fulltext Suppression of non-Albicans candida species (NAC) biofilm formation by probiotic Streptococcus salivarius

Sharmeen Nellisa Soffian, Nurul Alia Risma Rismayuddin, Munirah Mokhtar, Mohd Hafiz Arzmi

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):41-41.
MyJurnal

Introduction:Candida spp. are most common opportunistic pathogenic yeast that inhabit human oral cavity, epider-mis, gastrointestinal tract, and vagina leading to candidiasis. The transition of this yeast from commensal to potent pathogen is facilitated by numbers of virulence factors including biofilm formation. While most reports on candidi-asis are associated with formation Candida albicans biofilms, however, non-albicans Candida species prevalence is of growing concern. Recently, the use of probiotics as antifungal and antibiofilm has gained an increasing attention. As such, we aim to evaluate the inhibitory effect of monomicrobial and polymicrobial of Streptococcus salivariuson six strains of NAC namely Candida dubliniensis, Candida glabrata, Candida krusei, Candida lusitanaei, Candida parapsilosis and Candida tropicalis. Methods: Antifungal activity of S. salivarius on NAC species was performed using well diffusion method on Mueller Hinton Agar (MHA) and the diameter of inhibition zone were assessed. For formation of monomicrobial biofilm, standardized cell suspensions of NAC species (1 x 105 cells/ml) and probiotic Streptococcus salivarius (1 x 106 cells/ml) were grown in RPMI or nutrient broth media at 37°C for 72 h. Meanwhile to study polymicrobial biofilm of both NAC and S. salivarius, similar protocol was employed by inoculating both microorganisms with a similar cell density as in monomicrobial. Finally, biofilm formation was assessed through quantification of total biomass by crystal violet (CV) assay and the absorbance of adherent biofilm was measured in triplicate at 620nm. Results: Antifungal susceptibility testing of S. salivarius on all six NAC species discerned no zone of inhibition. Furthermore, our results showed variability of monomicrobial and polymicrobial biofilm biomass between NAC species and growth medium. All six polymicrobial NB-grown and RPMI-grown exhibited decreased of the biofilm formation. C. parapsilosis co-cultured with S. salivarius in NB medium had shown lowest biofilm bio-mass by 75.51+_1.34% while in RPMI medium, C. lusitanaei demonstrated with most reduced biofilm biomass by 67.03+_5.19. Conclusion: Our study elucidated the antagonistic relationship between Streptococcus salivarius and non-albicans Candida by supressing the growth of polymicrobial biofilm and pseudohyphae/hyphae of NAC species.

Matched MeSH terms: Hyphae
Symbiotic interaction of endophytic bacteria with arbuscular mycorrhizal fungi and its antagonistic effect on Ganoderma boninense

Sundram S, Meon S, Seman IA, Othman R

J Microbiol, 2011 Aug;49(4):551-7.
PMID: 21887636 DOI: 10.1007/s12275-011-0489-3

Endophytic bacteria (Pseudomonas aeruginosa UPMP3 and Burkholderia cepacia UMPB3), isolated from within roots of oil palm (Elaeis guineensis Jacq.) were tested for their presymbiotic effects on two arbuscular mcorrhizal fungi, Glomus intraradices UT126 and Glomus clarum BR152B). These endophytic bacteria were also tested for antagonistic effects on Ganoderma boninense PER 71, a white wood rot fungal pathogen that causes a serious disease in oil palm. Spore germination and hyphal length of each arbuscular mycorrhizal fungal (AMF) pairing with endophytic bacteria was found to be significantly higher than spores plated in the absence of bacteria. Scanning electron microscopy (SEM) showed that the endophytic bacteria were scattered, resting or embedded on the surface hyaline layer or on the degraded walls of AMF spores, possibly feeding on the outer hyaline spore wall. The antagonistic effect of the endophytic bacteria was expressed as severe morphological abnormalities in the hyphal structures of G. boninense PER 71. The effects of the endophytic bacteria on G. boninense PER 71 hyphal structures were observed clearly under SEM. Severe inter-twisting, distortion, lysis and shriveling of the hyphal structures were observed. This study found that the effect of endophytic bacteria on G. intraradices UT126 and G. clarum BR152B resembled that of a mycorrhiza helper bacteria (MHB) association because the association significantly promoted AMF spore germination and hyphal length. However, the endophytic bacteria were extremely damaging to G. boninense PER 71.

Matched MeSH terms: Hyphae
Fulltext The effect of synbiotic Streptococcus salivarius K12 and Musa acuminata on Candida albicans biofilm formation

Nurul Alia Risma Rismayuddin, Munirah Mokhtar, Noratikah Othman, Ahmad Faisal Ismail, Mohd Hafiz Arzmi

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):37-37.
MyJurnal

Introduction:Candida albicans is an opportunistic fungus that is associated with oral carcinogenesis. In addition, biofilm formation has been one of the important virulence factors of the yeast. Streptococcus salivarius K12 is an oral probiotic while Musa acuminata is a well-known prebiotic. The objective of this study is to investigate the effect of S. salivarius K12 and M. acuminata skin aqueous extract (synbiotic) on C. albicans with the hypothesis that S. salivariusK12 and M. acuminata inhibit C. albicans biofilm formation. Methods: To develop mono-species biofilm, C. albicans(ATCC MYA-4901 and cancer isolates, ALC2 and ALC3 strains) and S. salivarius K12 were standardised to 105 cells and 106 cells, respectively and grown in 96-well plate in nutrient broth (NB) or RPMI at 37 °C for 72 h. Polymicro-bial biofilms were developed by inoculating both microorganisms in the same well with similar cell number as in mono-species. To determine the effect of synbiotic, similar protocol was repeated by mixing with 800 mg mL-1 of M. acuminata skin extract and incubated at 37 °C for 72 h. The medium was replenished at every 24 h, aseptically. Finally, the biofilms were assessed using crystal violet assay and the optical density was measured at OD620nm. Results:C. albicans strain MYA-4901 and ALC3, when grown in polymicrobial with S. salivarius K12 in NB that is predominated by yeast-form C. albicans, exhibited decreased biofilms by 71.40±11.7% and 49.40±3.9%, respec-tively when compared to the expected biofilms. Meanwhile in RPMI, which C. albicans strain ATCC MYA-4901, ALC2 and ALC3 were predominated by hyphal-form showed decreased biofilms by 72.0±26.7%, 53.4±14.4% and 65.7±6.7%, respectively when compared to the expected biofilms. Conclusion:S. salivarius K12 and M. acuminata skin extract synbiotic inhibit biofilm formation of C. albicans yeast and hyphal forms thus supported the hypothesis of the present study.

Matched MeSH terms: Hyphae
The inhibitory effects of aureobasidin A on Candida planktonic and biofilm cells

Tan HW, Tay ST

Mycoses, 2013 Mar;56(2):150-6.
PMID: 22882276 DOI: 10.1111/j.1439-0507.2012.02225.x

Aureobasidin A (AbA) is a cyclic depsipeptide antifungal compound that inhibits a wide range of pathogenic fungi. In this study, the in vitro susceptibility of 92 clinical isolates of various Candida species against AbA was assessed by determining the planktonic and biofilm MICs of the isolates. The MIC(50) and MIC(90) of the planktonic Candida yeast were 1 and 1 μg ml(-1), respectively, whereas the biofilm MIC(50) and MIC(90) of the isolates were 8 and ≥64 μg ml(-1) respectively. This study demonstrates AbA inhibition on filamentation and biofilm development of C. albicans. The production of short hyphae and a lack of filamentation might have impaired biofilm development of AbA-treated cells. The AbA resistance of mature Candidia biofilms (24 h adherent population) was demonstrated in this study.

Matched MeSH terms: Hyphae/drug effects; Hyphae/growth & development
Fulltext Transciptome profiling at early infection of Elaeis guineensis by Ganoderma boninense provides novel insights on fungal transition from biotrophic to necrotrophic phase

Bahari MNA, Sakeh NM, Abdullah SNA, Ramli RR, Kadkhodaei S

BMC Plant Biol, 2018 Dec 29;18(1):377.
PMID: 30594134 DOI: 10.1186/s12870-018-1594-9

BACKGROUND: Basal stem rot (BSR) caused by hemibiotroph Ganoderma boninense is a devastating disease resulting in a major loss to the oil palm industry. Since there is no physical symptom in oil palm at the early stage of G. boninense infection, characterisation of molecular defense responses in oil palm during early interaction with the fungus is of the utmost importance. Oil palm (Elaeis guineensis) seedlings were artificially infected with G. boninense inoculums and root samples were obtained following a time-course of 0, 3, 7, and 11 days-post-inoculation (d.p.i) for RNA sequencing (RNA-seq) and identification of differentially expressed genes (DEGs).
RESULTS: The host counter-attack was evidenced based on fungal hyphae and Ganoderma DNA observed at 3 d.p.i which became significantly reduced at 7 and 11 d.p.i. DEGs revealed upregulation of multifaceted defense related genes such as PR-protein (EgPR-1), protease inhibitor (EgBGIA), PRR protein (EgLYK3) chitinase (EgCht) and expansin (EgEXPB18) at 3 d.p.i and 7 d.p.i which dropped at 11 d.p.i. Later stage involved highly expressed transcription factors EgERF113 and EgMYC2 as potential regulators of necrotrophic defense at 11 d.p.i. The reactive oxygen species (ROS) elicitor: peroxidase (EgPER) and NADPH oxidase (EgRBOH) were upregulated and maintained throughout the treatment period. Growth and nutrient distribution were probably compromised through suppression of auxin signalling and iron uptake genes.
CONCLUSIONS: Based on the analysis of oil palm gene expression, it was deduced that the biotrophic phase of Ganoderma had possibly occurred at the early phase (3 until 7 d.p.i) before being challenged by the fungus via switching its lifestyle into the necrotrophic phase at later stage (11 d.p.i) and finally succumbed the host. Together, the findings suggest the dynamic defense process in oil palm and potential candidates that can serve as phase-specific biomarkers at the early stages of oil palm-G. boninense interaction.

Matched MeSH terms: Hyphae
Transcriptome profiling of endothelial cells during infections with high and low densities of C. albicans cells

Lim CS, Rosli R, Seow HF, Chong PP

Int J Med Microbiol, 2011 Aug;301(6):536-46.
PMID: 21371935 DOI: 10.1016/j.ijmm.2010.12.002

Systemic infections of Candida albicans, the most prevalent fungal pathogen in humans, are on the rise in recent years. However, the exact mode of pathogenesis of this fungus is still not well elucidated. Previous studies using C. albicans mutants locked into the yeast form via gene deletion found that this form was avirulent and did not induce significant differential expression of host genes in vitro. In this study, a high density of C. albicans was used to infect human umbilical vein endothelial cells (HUVEC), resulting in yeast-form infections, whilst a low density of C. albicans resulted in hyphae infections. Transcriptional profiling of HUVEC response to these infections showed that high densities of C. albicans induced a stronger, broader transcriptional response from HUVEC than low densities of C. albicans infection. Many of the genes that were significantly differentially expressed were involved in apoptosis and cell death. In addition, conditioned media from the high-density infections caused a significant reduction in HUVEC viability, suggesting that certain molecules released during C. albicans and HUVEC interactions were capable of causing cell death. This study has shown that C. albicans yeast-forms, at high densities, cannot be dismissed as avirulent, but instead could possibly contribute to C. albicans pathogenesis.

Matched MeSH terms: Hyphae/cytology; Hyphae/growth & development
Fulltext Ultra-morphological changes of Trichophyton rubrum treated with hydroxychavicol

Ridzuan, P.M., Nasir Mohamad, Salwani Ismail, Nor Iza A. Rahman, Sanusi, N.A., Rabiatul Adawiyah Umar, et al.

International Medical Journal Malaysia, 2017;16(2):65-71.
MyJurnal

Trichophyton rubrum is a common pathogenic fungal species that is responsible for causing infection on
human skin, hair and nail. The antifungal-resistant strains complicate the treatment regime.
Hydroxychavicol (HC) is one of the main compounds from Piper betel leaf that have antifungal potential and
its mechanism of action has not been studied yet. The objective of this preliminary study to determine the
antifungal properties of HC against T. rubrum using transmission electron microscope (TEM) on gross and
ultrastructure of T. rubrum hypha. T. rubrum was treated with HC and miconazole (MI) at concentrations of
1.25, 2.5, 5 and 10 mg/mL for 1, 3, 5 and 7 days continuously. Generally, fungi structures became more
severely damaged at increasing treatment duration. Microscopically, the fungi’s cell wall treated with HC
showed a rough surface, shrinkage and demolition similar to the MI treated group. The fungi organelles were
also demolished and disorganized. This study revealed that HC has the ability to inhibit T. rubrum growth
and has potential to be an antifungal agent for skin infections.

Matched MeSH terms: Hyphae

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links