Displaying publications 101 - 111 of 111 in total

Abstract:
Sort:
  1. Md Lasim A, Mohd Ngesom AM, Nathan S, Abdul Razak F, Abdul Halim M, Mohd-Saleh W, et al.
    PeerJ, 2024;12:e17096.
    PMID: 38699181 DOI: 10.7717/peerj.17096
    BACKGROUND: Leptospirosis is a water-related zoonotic disease. The disease is primarily transmitted from animals to humans through pathogenic Leptospira bacteria in contaminated water and soil. Rivers have a critical role in Leptospira transmissions, while co-infection potentials with other waterborne bacteria might increase the severity and death risk of the disease.

    METHODS: The water samples evaluated in this study were collected from four recreational forest rivers, Sungai Congkak, Sungai Lopo, Hulu Perdik, and Gunung Nuang. The samples were subjected to next-generation sequencing (NGS) for the 16S rRNA and in-depth metagenomic analysis of the bacterial communities.

    RESULTS: The water samples recorded various bacterial diversity. The samples from the Hulu Perdik and Sungai Lopo downstream sampling sites had a more significant diversity, followed by Sungai Congkak. Conversely, the upstream samples from Gunung Nuang exhibited the lowest bacterial diversity. Proteobacteria, Firmicutes, and Acidobacteria were the dominant phyla detected in downstream areas. Potential pathogenic bacteria belonging to the genera Burkholderiales and Serratia were also identified, raising concerns about co-infection possibilities. Nevertheless, Leptospira pathogenic bacteria were absent from all sites, which is attributable to its limited persistence. The bacteria might also be washed to other locations, contributing to the reduced environmental bacterial load.

    CONCLUSION: The present study established the presence of pathogenic bacteria in the river ecosystems assessed. The findings offer valuable insights for designing strategies for preventing pathogenic bacteria environmental contamination and managing leptospirosis co-infections with other human diseases. Furthermore, closely monitoring water sample compositions with diverse approaches, including sentinel programs, wastewater-based epidemiology, and clinical surveillance, enables disease transmission and outbreak early detections. The data also provides valuable information for suitable treatments and long-term strategies for combating infectious diseases.

  2. Hashim NH, Bharudin I, Nguong DL, Higa S, Bakar FD, Nathan S, et al.
    Extremophiles, 2013 Jan;17(1):63-73.
    PMID: 23132550 DOI: 10.1007/s00792-012-0494-4
    The psychrophilic yeast Glaciozyma antarctica demonstrated high antifreeze activity in its culture filtrate. The culture filtrate exhibited both thermal hysteresis (TH) and ice recrystallization inhibition (RI) properties. The TH of 0.1 °C was comparable to that previously reported for bacteria and fungi. A genome sequence survey of the G. antarctica genome identified a novel antifreeze protein gene. The cDNA encoded a 177 amino acid protein with 30 % similarity to a fungal antifreeze protein from Typhula ishikariensis. The expression levels of AFP1 were quantified via real time-quantitative polymerase chain reaction (RT-qPCR), and the highest expression levels were detected within 6 h of growth at -12 °C. The cDNA of the antifreeze protein was cloned into an Escherichia coli expression system. Expression of recombinant Afp1 in E. coli resulted in the formation of inclusion bodies that were subsequently denatured by treatment with urea and allowed to refold in vitro. Activity assays of the recombinant Afp1 confirmed the antifreeze protein properties with a high TH value of 0.08 °C.
  3. Sam KK, Gan CP, Yee PS, Chong CE, Lim KP, Karen-Ng LP, et al.
    Oral Oncol, 2012 Nov;48(11):1128-35.
    PMID: 22705356 DOI: 10.1016/j.oraloncology.2012.05.016
    The presence of a variety of MDM2 splice variants has been reported in a range of different tumor types and is associated with poor patient prognosis. Furthermore, several MDM2 variants have been shown to have oncogenic properties. Despite this, MDM2 splice variants have not been comprehensively characterized in oral squamous cell carcinoma (OSCC).
  4. Chin CY, Hara Y, Ghazali AK, Yap SJ, Kong C, Wong YC, et al.
    BMC Genomics, 2015;16:471.
    PMID: 26092034 DOI: 10.1186/s12864-015-1692-0
    Chronic bacterial infections occur as a result of the infecting pathogen's ability to live within a biofilm, hence escaping the detrimental effects of antibiotics and the immune defense system. Burkholderia pseudomallei, a gram-negative facultative pathogen, is distinctive in its ability to survive within phagocytic and non-phagocytic cells, to persist in vivo for many years and subsequently leading to relapse as well as the development of chronic disease. The capacity to persist has been attributed to the pathogen's ability to form biofilm. However, the underlying biology of B. pseudomallei biofilm development remains unresolved.
  5. Nyon MP, Rice DW, Berrisford JM, Hounslow AM, Moir AJ, Huang H, et al.
    J Mol Biol, 2009 Jan 9;385(1):226-35.
    PMID: 18983850 DOI: 10.1016/j.jmb.2008.10.050
    Cutinase belongs to a group of enzymes that catalyze the hydrolysis of esters and triglycerides. Structural studies on the enzyme from Fusarium solani have revealed the presence of a classic catalytic triad that has been implicated in the enzyme's mechanism. We have solved the crystal structure of Glomerella cingulata cutinase in the absence and in the presence of the inhibitors E600 (diethyl p-nitrophenyl phosphate) and PETFP (3-phenethylthio-1,1,1-trifluoropropan-2-one) to resolutions between 2.6 and 1.9 A. Analysis of these structures reveals that the catalytic triad (Ser136, Asp191, and His204) adopts an unusual configuration with the putative essential histidine His204 swung out of the active site into a position where it is unable to participate in catalysis, with the imidazole ring 11 A away from its expected position. Solution-state NMR experiments are consistent with the disrupted configuration of the triad observed crystallographically. H204N, a site-directed mutant, was shown to be catalytically inactive, confirming the importance of this residue in the enzyme mechanism. These findings suggest that, during its catalytic cycle, cutinase undergoes a significant conformational rearrangement converting the loop bearing the histidine from an inactive conformation, in which the histidine of the triad is solvent exposed, to an active conformation, in which the triad assumes a classic configuration.
  6. Chellappan DK, Chellian J, Ng ZY, Sim YJ, Theng CW, Ling J, et al.
    Biomed Pharmacother, 2017 Dec;96:768-781.
    PMID: 29054093 DOI: 10.1016/j.biopha.2017.10.058
    Pazopanib is a relatively new compound to be introduced into the chemotherapy field. It is thought to have decent anti-angiogenic properties, which gives an additional hope for the treatment of certain types of cancers. A systematic review solely discussing about pazopanib and its anti-angiogenic effect is yet to be published to date, despite several relevant clinical trials being conducted over the recent years. In this review, we aim to investigate the mechanism of pazopanib's anti-angiogenic effect and its effectiveness in treating several cancers. We have included, in this study, findings from electronically searchable data from randomized clinical trials, clinical studies, cohort studies and other relevant articles. A total of 352 studies were included in this review. From the studies, the effect of pazopanib in various cancers or models was observed and recorded. Study quality is indefinite, with a few decent quality articles. The most elaborately studied cancers include renal cell carcinoma, solid tumors, advanced solid tumors, soft tissue sarcoma, breast cancer and gynecological cancers. In addition, several less commonly studied cancers are included in the studies as well. Pazopanib had demonstrated its anti-angiogenic effect based on favorable results observed in cancers, which are caused by angiogenesis-related mechanisms, such as renal cell carcinoma, solid tumors, advanced solid tumors and soft tissue sarcoma. This review was conducted to study, analyze and review the anti-angiogenic properties of pazopanib in various cancers. The results obtained can provide a decent reference when considering treatment options for angiogenesis-related malignancies. Furthermore, the definite observations of the anti-angiogenic effects of pazopanib could provide newer insights leading to the future development of drugs of the same mechanism with increased efficiency and reduced adverse effects.
  7. Ang MY, Binti Mohamad Farook NA, Kamarudin N, Lam SD, Di Gregorio S, Tengku Jamaluddin TZM, et al.
    Microbiol Resour Announc, 2022 Dec 15;11(12):e0086722.
    PMID: 36413024 DOI: 10.1128/mra.00867-22
    Draft genome sequences were obtained for four methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from various wards of the Hospital Canselor Tuanku Muhriz (HCTM), Kuala Lumpur, Malaysia, in 2017. Using different bioinformatics tools, we annotated the draft genomes and identified multiple antimicrobial resistance genes.
  8. Ramly NZ, Dix SR, Ruzheinikov SN, Sedelnikova SE, Baker PJ, Chow YP, et al.
    Commun Biol, 2021 03 19;4(1):376.
    PMID: 33742128 DOI: 10.1038/s42003-021-01904-w
    In infections by apicomplexan parasites including Plasmodium, Toxoplasma gondii, and Eimeria, host interactions are mediated by proteins including families of membrane-anchored cysteine-rich surface antigens (SAGs) and SAG-related sequences (SRS). Eimeria tenella causes caecal coccidiosis in chickens and has a SAG family with over 80 members making up 1% of the proteome. We have solved the structure of a representative E. tenella SAG, EtSAG19, revealing that, despite a low level of sequence similarity, the entire Eimeria SAG family is unified by its three-layer αβα fold which is related to that of the CAP superfamily. Furthermore, sequence comparisons show that the Eimeria SAG fold is conserved in surface antigens of the human coccidial parasite Cyclospora cayetanensis but this fold is unrelated to that of the SAGs/SRS proteins expressed in other apicomplexans including Plasmodium species and the cyst-forming coccidia Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti. However, despite having very different structures, Consurf analysis showed that Eimeria SAG and Toxoplasma SRS families each exhibit marked hotspots of sequence hypervariability that map to their surfaces distal to the membrane anchor. This suggests that the primary and convergent purpose of the different structures is to provide a platform onto which sequence variability can be imposed.
  9. Lee SH, Wong RR, Chin CY, Lim TY, Eng SA, Kong C, et al.
    Proc Natl Acad Sci U S A, 2013 Sep 10;110(37):15067-72.
    PMID: 23980181 DOI: 10.1073/pnas.1311725110
    Burkholderia pseudomallei is a Gram-negative soil bacterium that infects both humans and animals. Although cell culture studies have revealed significant insights into factors contributing to virulence and host defense, the interactions between this pathogen and its intact host remain to be elucidated. To gain insights into the host defense responses to B. pseudomallei infection within an intact host, we analyzed the genome-wide transcriptome of infected Caenorhabditis elegans and identified ∼6% of the nematode genes that were significantly altered over a 12-h course of infection. An unexpected feature of the transcriptional response to B. pseudomallei was a progressive increase in the proportion of down-regulated genes, of which ELT-2 transcriptional targets were significantly enriched. ELT-2 is an intestinal GATA transcription factor with a conserved role in immune responses. We demonstrate that B. pseudomallei down-regulation of ELT-2 targets is associated with degradation of ELT-2 protein by the host ubiquitin-proteasome system. Degradation of ELT-2 requires the B. pseudomallei type III secretion system. Together, our studies using an intact host provide evidence for pathogen-mediated host immune suppression through the destruction of a host transcription factor.
  10. Shaibullah S, Shuhaimi N, Ker DS, Mohd-Sharif N, Ho KL, Teh AH, et al.
    Commun Biol, 2023 Sep 08;6(1):920.
    PMID: 37684342 DOI: 10.1038/s42003-023-05265-4
    Burkholderia pseudomallei is a highly versatile pathogen with ~25% of its genome annotated to encode hypothetical proteins. One such hypothetical protein, BPSL1038, is conserved across seven bacterial genera and 654 Burkholderia spp. Here, we present a 1.55 Å resolution crystal structure of BPSL1038. The overall structure folded into a modified βαββαβα ferredoxin fold similar to known Cas2 nucleases. The Cas2 equivalent catalytic aspartate (D11) pairs are conserved in BPSL1038 although B. pseudomallei has no known CRISPR associated system. Functional analysis revealed that BPSL1038 is a nuclease with endonuclease activity towards double-stranded DNA. The DNase activity is divalent ion independent and optimum at pH 6. The concentration of monovalent ions (Na+ and K+) is crucial for nuclease activity. An active site with a unique D11(X20)SST motif was identified and proposed for BPSL1038 and its orthologs. Structure modelling indicates the catalytic role of the D11(X20)SST motif and that the arginine residues R10 and R30 may interact with the nucleic acid backbone. The structural similarity of BPSL1038 to Cas2 proteins suggests that BPSL1038 may represent a sub-family of nucleases that share a common ancestor with Cas2.
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links