Displaying publications 161 - 180 of 897 in total

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  1. Predictive Potential of PD-L1, TYMS, and DCC Expressions in Treatment Outcome of Colorectal Carcinoma
    Onwe EE, Ghani FA, Abdullah M, Osman M, Zin RRM, Vivian AN, et al.
    Adv Exp Med Biol, 2020;1292:97-112.
    PMID: 32542457 DOI: 10.1007/5584_2020_521
    Colorectal carcinoma (CRC) is a malignancy of epithelial origin in the large bowel. The elucidation of the biological functions of programmed cell death ligand-1 (PD-L1), thymidylate synthase (TYMS), and deleted in colorectal cancer (DCC) biomarkers including their roles in the pathophysiology of CRC - has led to their applications in diagnostic and chemo-pharmaceutics. We investigated whether PD-L1, TYMS, and DCC protein expression in CRC tumors are predictive biomarkers of treatment outcome for CRC patients. The expressions of PD-L1, TYMS, and DCC were evaluated by immunohistochemistry (IHC) in 91 paraffin-embedded samples from patients who underwent colectomy procedure in Hospital Serdang, Selangor, Malaysia. There was high expression of DCC in most cases: 84.6% (77/91). PD-L1 showed low expression in 93.4% (86/91) of cases and high expression in 6.6% (5/91) of cases. Low and high expressions of TYMS were detected in 53.8% (49/91) and 46.2% (42/91) of the CRC cases, respectively. There was a significant association between the TYMS expression and gender (P 
    Matched MeSH terms: Thymidylate Synthase/biosynthesis; Antigens, CD274/biosynthesis
  2. Genome Mining Reveals the Biosynthetic Pathways of Polyhydroxyalkanoate and Ectoines of the Halophilic Strain Salinivibrio proteolyticus M318 Isolated from Fermented Shrimp Paste
    Van Thuoc D, Loan TT, Trung TA, Van Quyen N, Tung QN, Tien PQ, et al.
    Mar Biotechnol (NY), 2020 Oct;22(5):651-660.
    PMID: 32827070 DOI: 10.1007/s10126-020-09986-z
    Salinivibrio proteolyticus M318, a halophilic bacterium isolated from fermented shrimp paste, is able to produce polyhydroxyalkanoate (PHA) from different carbon sources. In this study, we report the whole-genome sequence of strain M138, which comprises 2 separated chromosomes and 2 plasmids, and the complete genome contains 3,605,935 bp with an average GC content of 49.9%. The genome of strain M318 contains 3341 genes, 98 tRNA genes, and 28 rRNA genes. The 16S rRNA gene sequence and average nucleotide identity analysis associated with morphological and biochemical tests showed that this strain has high homology to the reference strain Salinivibrio proteolyticus DSM 8285. The genes encoding key enzymes for PHA and ectoine synthesis were identified from the bacterial genome. In addition, the TeaABC transporter responsible for ectoine uptake from the environment and the operon doeABXCD responsible for the degradation of ectoine were also detected. Strain M318 was able to produce poly(3-hydroxybutyrate) [P(3HB)] from different carbon sources such as glycerol, maltose, glucose, fructose, and starch. The ability to produce ectoines at different NaCl concentrations was investigated. High ectoine content of 26.2% of cell dry weight was obtained by this strain at 18% NaCl. This report provides genetic information regarding adaptive mechanisms of strain M318 to stress conditions, as well as new knowledge to facilitate the application of this strain as a bacterial cell factory for the production of PHA and ectoine.
    Matched MeSH terms: Amino Acids, Diamino/biosynthesis*; Polyhydroxyalkanoates/biosynthesis*
  3. Fulltext Molecular cloning and xenobiotic induction of seven novel cytochrome P450 monooxygenases in Aedes albopictus
    Chan HH, Wajidi MF, Zairi J
    J Insect Sci, 2014;14:163.
    PMID: 25399430 DOI: 10.1093/jisesa/ieu025
    Cytochrome P450 monooxygenase (P450) is a superfamily of enzymes that is important in metabolism of endogenous and exogenous compounds. In insects, these enzymes confer resistance to insecticides through its metabolic activities. Members of P450 from family 6 in insects are known to play a role in such function. In this study, we have isolated seven novel family 6 P450 from Aedes albopictus (Skuse) (Diptera: Culicidae), a vector of dengue and chikungunya fever. Induction profile of these seven genes was studied using several insecticides and xenobiotics. It was found that deltamethrin and permethrin did not induce expression of any genes. Another insecticide, temephos, inhibited expression of CYP6P15 for fivefold and twofold for CYP6N29, CYP6Y7, and CYP6Z18. In addition, copper II sulfate induced expression of CYP6M17 and CYP6N28 for up to sixfold. Benzothiazole (BZT), a tire leachate induced the expression of CYP6M17 by fourfold, CYP6N28 by sevenfold, but inhibited the expression of CYP6P15 for threefold and CYP6Y7 for twofold. Meanwhile, piperonyl butoxide (PBO) induced the expression CYP6N28 (twofold), while it inhibited the expression of CYP6P15 (fivefold) and CYP6Y7 (twofold). Remarkably, all seven genes were induced two- to eightfold by acetone in larval stage, but not adult stage. Expression of CYP6N28 was twofold higher, while expression of CYP6P15 was 15-fold lower in adult than larva. The other five P450s were not differentially expressed between the larvae and adult. This finding showed that acetone can be a good inducer of P450 in Ae. albopictus. On the other hand, temephos can act as good suppressor of P450, which may affect its own bioefficacy because it needs to be bioactivated by P450. To the best of our knowledge, this is the first report on acetone-inducible P450 in insects. Further study is needed to characterize the mechanisms involved in acetone induction in P450.
    Matched MeSH terms: Cytochrome P-450 Enzyme System/biosynthesis; Insect Proteins/biosynthesis
  4. Fulltext The PCA and LDA analysis on the differential expression of proteins in breast cancer
    Liang S, Singh M, Dharmaraj S, Gam LH
    Dis Markers, 2010;29(5):231-42.
    PMID: 21206008 DOI: 10.3233/DMA-2010-0753
    Breast cancer is a leading cause of mortality in women. In Malaysia, it is the most common cancer to affect women. The most common form of breast cancer is infiltrating ductal carcinoma (IDC). A proteomic approach was undertaken to identify protein profile changes between cancerous and normal breast tissues from 18 patients. Two protein extracts; aqueous soluble and membrane associated protein extracts were studied. Thirty four differentially expressed proteins were identified. The intensities of the proteins were used as variables in PCA and reduced data of six principal components (PC) were subjected to LDA in order to evaluate the potential of these proteins as collective biomarkers for breast cancer. The protein intensities of SEC13-like 1 (isoform b) and calreticulin contributed the most to the first PC while the protein intensities of fibrinogen beta chain precursor and ATP synthase D chain contributed the most to the second PC. Transthyretin precursor and apolipoprotein A-1 precursor contributed the most to the third PC. The results of LDA indicated good classification of samples into normal and cancerous types when the first 6 PCs were used as the variables. The percentage of correct classification was 91.7% for the originally grouped tissue samples and 88.9% for cross-validated samples.
    Matched MeSH terms: Protein Biosynthesis; Biomarkers, Tumor/biosynthesis*
  5. Fulltext Metaplastic breast cancers frequently express immune checkpoint markers FOXP3 and PD-L1
    Kalaw E, Lim M, Kutasovic JR, Sokolova A, Taege L, Johnstone K, et al.
    Br J Cancer, 2020 11;123(11):1665-1672.
    PMID: 32939056 DOI: 10.1038/s41416-020-01065-3
    BACKGROUND: Metaplastic breast carcinoma encompasses a heterogeneous group of tumours with differentiation into squamous and/or spindle, chondroid, osseous or rhabdoid mesenchymal-looking elements. Emerging immunotherapies targeting Programmed Death Ligand 1 (PD-L1) and immune-suppressing T cells (Tregs) may benefit metaplastic breast cancer patients, which are typically chemo-resistant and do not express hormone therapy targets.

    METHODS: We evaluated the immunohistochemical expression of PD-L1 and FOXP3, and the extent of tumour infiltrating lymphocytes (TILs) in a large cohort of metaplastic breast cancers, with survival data.

    RESULTS: Metaplastic breast cancers were significantly enriched for PD-L1 positive tumour cells, compared to triple-negative ductal breast cancers (P 

    Matched MeSH terms: Forkhead Transcription Factors/biosynthesis*; Antigens, CD274/biosynthesis*
  6. Strategies for humanizing glycosylation pathways and producing recombinant glycoproteins in microbial expression systems
    Khan AH, Noordin R
    Biotechnol Prog, 2019 03;35(2):e2752.
    PMID: 30457225 DOI: 10.1002/btpr.2752
    Homogeneously glycosylated proteins are essential for analyzing the structure of N-glycans, studying their consequences inside cells, and developing therapeutic glycoproteins. However, the isolation of glycoproteins with homogeneous glycans from human is difficult since glycoforms slightly differ from each other with respect to molecular weight and charge. Microbial expression systems have numerous benefits in expression technology and have gained great attention, because they are more adaptable to the biotechnology industry. While selecting an expression host, the glycosylation pattern must be taken into account, because glycosylation strongly depends on cellular production system and selected production clone. This review discussed the technological developments in glycoengineering of microbial expression systems for humanizing the glycosylation profile and highlighted the expression potential of Leishmania expression system. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2752, 2019.
    Matched MeSH terms: Glycoproteins/biosynthesis*; Recombinant Proteins/biosynthesis*
  7. Insensitivity of bacterial nucleic acid biosyntheses to a morphine-like narcotic
    Wolfe AD, Hahn FE
    Naturwissenschaften, 1975 Feb;62(2):99.
    PMID: 1683
    Matched MeSH terms: DNA, Bacterial/biosynthesis*; RNA, Bacterial/biosynthesis*
  8. Fulltext Preparation of kenaf stem hemicellulosic hydrolysate and its fermentability in microbial production of xylitol by Escherichia coli BL21
    Shah SSM, Luthfi AAI, Low KO, Harun S, Manaf SFA, Illias RM, et al.
    Sci Rep, 2019 03 11;9(1):4080.
    PMID: 30858467 DOI: 10.1038/s41598-019-40807-z
    Kenaf (Hibiscus cannabinus L.), a potential fibre crop with a desirably high growth rate, could serve as a sustainable feedstock in the production of xylitol. In this work, the extraction of soluble products of kenaf through dilute nitric-acid hydrolysis was elucidated with respect to three parameters, namely temperature, residence time, and acid concentration. The study will assist in evaluating the performance in terms of xylose recovery. The result point out that the maximum xylose yield of 30.7 g per 100 g of dry kenaf was attained from 2% (v/v) HNO3 at 130 °C for 60 min. The detoxified hydrolysate was incorporated as the primary carbon source for subsequent fermentation by recombinant Escherichia coli and the performance of strain on five different semi-synthetic media on xylitol production were evaluated herein. Among these media, batch cultivation in a basal salt medium (BSM) afforded the highest xylitol yield of 0.35 g/g based on xylose consumption, which corresponded to 92.8% substrate utilization after 38 h. Subsequently, fermentation by E. coli in the xylose-based kenaf hydrolysate supplemented with BSM resulting in 6.8 g/L xylitol which corresponding to xylitol yield of 0.38 g/g. These findings suggested that the use of kenaf as the fermentation feedstock could be advantageous for the development of sustainable xylitol production.
    Matched MeSH terms: Protein Hydrolysates/biosynthesis; Xylitol/biosynthesis
  9. Fulltext Biosynthesis of Saxitoxin in Marine Dinoflagellates: An Omics Perspective
    Akbar MA, Mohd Yusof NY, Tahir NI, Ahmad A, Usup G, Sahrani FK, et al.
    Mar Drugs, 2020 Feb 05;18(2).
    PMID: 32033403 DOI: 10.3390/md18020103
    Saxitoxin is an alkaloid neurotoxin originally isolated from the clam Saxidomus giganteus in 1957. This group of neurotoxins is produced by several species of freshwater cyanobacteria and marine dinoflagellates. The saxitoxin biosynthesis pathway was described for the first time in the 1980s and, since then, it was studied in more than seven cyanobacterial genera, comprising 26 genes that form a cluster ranging from 25.7 kb to 35 kb in sequence length. Due to the complexity of the genomic landscape, saxitoxin biosynthesis in dinoflagellates remains unknown. In order to reveal and understand the dynamics of the activity in such impressive unicellular organisms with a complex genome, a strategy that can carefully engage them in a systems view is necessary. Advances in omics technology (the collective tools of biological sciences) facilitated high-throughput studies of the genome, transcriptome, proteome, and metabolome of dinoflagellates. The omics approach was utilized to address saxitoxin-producing dinoflagellates in response to environmental stresses to improve understanding of dinoflagellates gene-environment interactions. Therefore, in this review, the progress in understanding dinoflagellate saxitoxin biosynthesis using an omics approach is emphasized. Further potential applications of metabolomics and genomics to unravel novel insights into saxitoxin biosynthesis in dinoflagellates are also reviewed.
    Matched MeSH terms: Saxitoxin/biosynthesis*; Protein Biosynthesis
  10. Fulltext Recombinant Production and Characterization of an Extracellular Subtilisin-Like Serine Protease from Acinetobacter baumannii of Fermented Food Origin
    Muhammed NS, Hussin N, Lim AS, Jonet MA, Mohamad SE, Jamaluddin H
    Protein J, 2021 06;40(3):419-435.
    PMID: 33870461 DOI: 10.1007/s10930-021-09986-5
    Acinetobacter baumannii is a ubiquitous bacteria that is increasingly becoming a formidable nosocomial pathogen. Due to its clinical relevance, studies on the bacteria's secretory molecules especially extracellular proteases are of interest primarily in relation to the enzyme's role in virulence. Besides, favorable properties that extracellular proteases possess may be exploited for commercial use thus there is a need to investigate extracellular proteases from Acinetobacter baumannii to gain insights into their catalytic properties. In this study, an extracellular subtilisin-like serine protease from Acinetobacter baumannii designated as SPSFQ that was isolated from fermented food was recombinantly expressed and characterized. The mature catalytically active form of SPSFQ shared a high percentage sequence identity of 99% to extracellular proteases from clinical isolates of Acinetobacter baumannii and Klebsiella pneumoniae as well as a moderately high percentage identity to other bacterial proteases with known keratinolytic and collagenolytic activity. The homology model of mature SPSFQ revealed its structure is composed of 10 β-strands, 8 α-helices, and connecting loops resembling a typical architecture of subtilisin-like α/β motif. SPSFQ is catalytically active at an optimum temperature of 40 °C and pH 9. Its activity is stimulated in the presence of Ca2+ and severely inhibited in the presence of PMSF. SPSFQ also displayed the ability to degrade several tissue-associated protein substrates such as keratin, collagen, and fibrin. Accordingly, our study shed light on the catalytic properties of a previously uncharacterized extracellular serine protease from Acinetobacter baumannii that warrants further investigations into its potential role as a virulence factor in pathogenicity and commercial applications.
    Matched MeSH terms: Recombinant Proteins/biosynthesis; Subtilisins/biosynthesis
  11. Fulltext Effect of CO(2) enrichment on synthesis of some primary and secondary metabolites in ginger (Zingiber officinale Roscoe)
    Ghasemzadeh A, Jaafar HZ
    Int J Mol Sci, 2011 Feb 10;12(2):1101-14.
    PMID: 21541046 DOI: 10.3390/ijms12021101
    The effect of two different CO(2) concentrations (400 and 800 μmol mol(-1)) on the photosynthesis rate, primary and secondary metabolite syntheses and the antioxidant activities of the leaves, stems and rhizomes of two Zingiber officinale varieties (Halia Bentong and Halia Bara) were assessed in an effort to compare and validate the medicinal potential of the subterranean part of the young ginger. High photosynthesis rate (10.05 μmol CO(2) m(-2)s(-1) in Halia Bara) and plant biomass (83.4 g in Halia Bentong) were observed at 800 μmol mol(-1) CO(2). Stomatal conductance decreased and water use efficiency increased with elevated CO(2) concentration. Total flavonoids (TF), total phenolics (TP), total soluble carbohydrates (TSC), starch and plant biomass increased significantly (P ≤ 0.05) in all parts of the ginger varieties under elevated CO(2) (800 μmol mol(-1)). The order of the TF and TP increment in the parts of the plant was rhizomes > stems > leaves. More specifically, Halia Bara had a greater increase of TF (2.05 mg/g dry weight) and TP (14.31 mg/g dry weight) compared to Halia Bentong (TF: 1.42 mg/g dry weight; TP: 9.11 mg/g dry weight) in average over the whole plant. Furthermore, plants with the highest rate of photosynthesis had the highest TSC and phenolics content. Significant differences between treatments and species were observed for TF and TP production. Correlation coefficient showed that TSC and TP content are positively correlated in both varieties. The antioxidant activity, as determined by the ferric reducing/antioxidant potential (FRAP) activity, increased in young ginger grown under elevated CO(2). The FRAP values for the leaves, rhizomes and stems extracts of both varieties grown under two different CO(2) concentrations (400 and 800 μmol mol(-1)) were significantly lower than those of vitamin C (3107.28 μmol Fe (II)/g) and α-tocopherol (953 μmol Fe (II)/g), but higher than that of BHT (74.31 μmol Fe (II)/g). These results indicate that the plant biomass, primary and secondary metabolite synthesis, and following that, antioxidant activities of Malaysian young ginger varieties can be enhanced through controlled environment (CE) and CO(2) enrichment.
    Matched MeSH terms: Flavonoids/biosynthesis*; Starch/biosynthesis*
  12. Human mammaglobin in breast cancer: a brief review of its clinical utility
    Al Joudi FS
    Indian J Med Res, 2014 May;139(5):675-85.
    PMID: 25027076
    Human mammaglobin is a member of the uteroglobin proteins family that has recently been tested as a specific marker for breast cancer. While low levels may be seen in normal breast tissue, expression is increased dramatically in breast cancer and is correlated with higher grade. Detection in blood and body fluids is also correlated with cancer metastasis, and its levels with prognosis. This promises to be a useful screen for early detection of breast cancer, especially in high risk individuals. Mammoglobin has also been used for immunotherapeutic targeting of breast cancer cells. However, there are some controversies regarding its diagnostic efficacy and prognostic value, which warrant further study.
    Matched MeSH terms: RNA, Messenger/biosynthesis; Mammaglobin A/biosynthesis
  13. Fulltext Pattern of hMLH1, hMSH2 and hMSH6 expression and clinical characteristics in a sample of Malaysian colorectal carcinoma cases
    Khoo JJ, Gunn A, Peh SC
    Malays J Pathol, 2013 Jun;35(1):45-57.
    PMID: 23817394 MyJurnal
    Malignant transformation from normal colonic mucosa to carcinomas may be accelerated by genetic loss or inactivation of genes of the DNA mismatch repair system. The aim of the study was to determine the local incidence and pattern of immunohistochemical expression of mismatch repair proteins namely: hMLH1, hMSH2 and hMSH6 in a series of colorectal carcinomas (CRCs) and correlate this to their clinical and pathological features. Forty-three out of 298 cases of CRCs (14.4%) showed abnormal staining pattern for mismatch repair proteins with a majority (65.1%) showing single hMLH1 loss. Tumours with mismatch repair defect (MMR-d) were frequently found at the right side of colon (p<0.001), poorly differentiated carcinomas (p<0.001), produced more mucin (p=0.007), exophytic growth (p=0.007) and were bigger (p=0.002) than tumours with no mismatch repair defect. Immunohistochemical stains for mismatch repair proteins could be done in local laboratories on these selected cases before referring for the expensive molecular test.
    Matched MeSH terms: DNA-Binding Proteins/biosynthesis*; Nuclear Proteins/biosynthesis*; Adaptor Proteins, Signal Transducing/biosynthesis*; MutS Homolog 2 Protein/biosynthesis*
  14. Fulltext Tamarindus indica extract alters release of alpha enolase, apolipoprotein A-I, transthyretin and Rab GDP dissociation inhibitor beta from HepG2 cells
    Chong UR, Abdul-Rahman PS, Abdul-Aziz A, Hashim OH, Junit SM
    PLoS One, 2012;7(6):e39476.
    PMID: 22724021 DOI: 10.1371/journal.pone.0039476
    The plasma cholesterol and triacylglycerol lowering effects of Tamarindus indica extract have been previously described. We have also shown that the methanol extract of T. indica fruit pulp altered the expression of lipid-associated genes including ABCG5 and APOAI in HepG2 cells. In the present study, effects of the same extract on the release of proteins from the cells were investigated using the proteomics approach.
    Matched MeSH terms: Phosphopyruvate Hydratase/biosynthesis*; Prealbumin/biosynthesis*; Apolipoprotein A-I/biosynthesis*; Guanine Nucleotide Dissociation Inhibitors/biosynthesis*
  15. Fulltext Expression and mutational analysis of GATA3 in Malaysian breast carcinomas
    Bong PN, Zakaria Z, Muhammad R, Abdullah N, Ibrahim N, Emran NA, et al.
    Malays J Pathol, 2010 Dec;32(2):117-22.
    PMID: 21329183 MyJurnal
    The GATA3 gene is a potential tumour marker and putative tumour suppressor gene in breast cancer. Its expression is associated with better prognosis and disease free survival in breast cancer patients. We aimed to evaluate GATA3 transcriptome expression and mutation in breast carcinomas and correlate its expression with oestrogen receptor (ER), progesterone receptor (PR), lymph node (LN) status, tumour grade and c-erbB-2 expression. Twenty-two breast infiltrating ductal carcinomas and paired normal tissues were used in Branch DNA assay to detect GATA3 mRNA expression. Normalized data for GATA3 mRNA expression were grouped according to the ER, PR and LN status, tumour grade and c-erbB-2 expression of the tumours. Statistical significance was tested using t-test and ANOVA at 95% confidence interval level. Mutational analysis of GATA3 was performed by direct sequencing of the coding regions of GATA3 mRNA. Our findings showed that GATA3 gene were over-expressed and under-expressed by > 2 fold change in 12 and 4 tested samples, respectively. Eighty per cent of ER positive breast carcinomas were GATA3 positive. There was a statistically significant correlation between GATA3 expression and ER at 95% confidence interval level between the study groups. On the contrary, GATA3 expression was not statistically significant with PR, LN, tumour grade and c-erbB-2 expression in our study. In addition, we observed that there was no mutation in mRNA coding region in 16 breast carcinomas that showed GATA3 differential gene expression. Our preliminary results suggested that GATA3 is linked to the ER. This scenario suggests that GATA3 may play a crucial role in oestrogen receptor positive breast cancer patients. Whether GATA3 expression is involved in regulating tumour cell growth in oestrogen responsive breast cancer is a key question that remains to be answered.
    Matched MeSH terms: Receptors, Estrogen/biosynthesis; Receptors, Progesterone/biosynthesis; Receptor, ErbB-2/biosynthesis; GATA3 Transcription Factor/biosynthesis
  16. Cloning and localization of immediate early response 2 (ier2) gene in the brain of medaka
    Moriya S, Chourasia D, Ng KW, Khel NB, Parhar IS
    J. Chem. Neuroanat., 2016 11;77:24-29.
    PMID: 27134039 DOI: 10.1016/j.jchemneu.2016.04.005
    Immediate early response (IER) 2 gene, a member of the IER family, is a gene of unknown function which is affected by external stimuli in the brain. In the present study, the full length sequence and localization of medaka (Oryzias latipes) ier2 was investigated in the brain to understand the functions of Ier2 in the future studies. The full length sequence of medaka ier2 was identified using a 3'-, 5'- rapid amplification of cDNA ends method, and distribution in the brain was identified using in situ hybridization. The identified full length ier2 mRNA consisted of 939 nucleotides spanning along 1 exon. The deduced amino acid sequence consisted of 171 amino acid residues which contains a highly conserved sequence, nuclear localization signal. ier2 mRNA was distributed in the telencephalon, midbrain and the hypothalamus. This highly conserved primary response gene Ier2 can be used to visualize and map functionally activated neuronal circuitry in the brain of medaka.
    Matched MeSH terms: RNA, Messenger/biosynthesis; Immediate-Early Proteins/biosynthesis; DNA, Complementary/biosynthesis; Fish Proteins/biosynthesis
  17. Fulltext Attachment of Salmonella strains to a plant cell wall model is modulated by surface characteristics and not by specific carbohydrate interactions
    Tan MS, Moore SC, Tabor RF, Fegan N, Rahman S, Dykes GA
    BMC Microbiol, 2016 09 15;16:212.
    PMID: 27629769 DOI: 10.1186/s12866-016-0832-2
    BACKGROUND: Processing of fresh produce exposes cut surfaces of plant cell walls that then become vulnerable to human foodborne pathogen attachment and contamination, particularly by Salmonella enterica. Plant cell walls are mainly composed of the polysaccharides cellulose, pectin and hemicelluloses (predominantly xyloglucan). Our previous work used bacterial cellulose-based plant cell wall models to study the interaction between Salmonella and the various plant cell wall components. We demonstrated that Salmonella attachment was favoured in the presence of pectin while xyloglucan had no effect on its attachment. Xyloglucan significantly increased the attachment of Salmonella cells to the plant cell wall model only when it was in association with pectin. In this study, we investigate whether the plant cell wall polysaccharides mediate Salmonella attachment to the bacterial cellulose-based plant cell wall models through specific carbohydrate interactions or through the effects of carbohydrates on the physical characteristics of the attachment surface.

    RESULTS: We found that none of the monosaccharides that make up the plant cell wall polysaccharides specifically inhibit Salmonella attachment to the bacterial cellulose-based plant cell wall models. Confocal laser scanning microscopy showed that Salmonella cells can penetrate and attach within the tightly arranged bacterial cellulose network. Analysis of images obtained from atomic force microscopy revealed that the bacterial cellulose-pectin-xyloglucan composite with 0.3 % (w/v) xyloglucan, previously shown to have the highest number of Salmonella cells attached to it, had significantly thicker cellulose fibrils compared to other composites. Scanning electron microscopy images also showed that the bacterial cellulose and bacterial cellulose-xyloglucan composites were more porous when compared to the other composites containing pectin.

    CONCLUSIONS: Our study found that the attachment of Salmonella cells to cut plant cell walls was not mediated by specific carbohydrate interactions. This suggests that the attachment of Salmonella strains to the plant cell wall models were more dependent on the structural characteristics of the attachment surface. Pectin reduces the porosity and space between cellulose fibrils, which then forms a matrix that is able to retain Salmonella cells within the bacterial cellulose network. When present with pectin, xyloglucan provides a greater surface for Salmonella cells to attach through the thickening of cellulose fibrils.

    Matched MeSH terms: Cellulose/biosynthesis; Glucans/biosynthesis; Pectins/biosynthesis; Xylans/biosynthesis
  18. Fulltext Ingestion of bacteria overproducing DnaK attenuates Vibrio infection of Artemia franciscana larvae
    Sung YY, Dhaene T, Defoirdt T, Boon N, MacRae TH, Sorgeloos P, et al.
    Cell Stress Chaperones, 2009 Nov;14(6):603-9.
    PMID: 19373565 DOI: 10.1007/s12192-009-0112-2
    Feeding of bacterially encapsulated heat shock proteins (Hsps) to invertebrates is a novel way to limit Vibrio infection. As an example, ingestion of Escherichia coli overproducing prokaryotic Hsps significantly improves survival of gnotobiotically cultured Artemia larvae upon challenge with pathogenic Vibrio campbellii. The relationship between Hsp accumulation and enhanced resistance to infection may involve DnaK, the prokaryotic equivalent to Hsp70, a major molecular chaperone in eukaryotic cells. In support of this proposal, heat-stressed bacterial strains LVS 2 (Bacillus sp.), LVS 3 (Aeromonas hydrophila), LVS 8 (Vibrio sp.), GR 8 (Cytophaga sp.), and GR 10 (Roseobacter sp.) were shown in this work to be more effective than nonheated bacteria in protecting gnotobiotic Artemia larvae against V. campbellii challenge. Immunoprobing of Western blots and quantification by enzyme-linked immunosorbent assay revealed that the amount of DnaK in bacteria and their ability to enhance larval resistance to infection by V. campbellii are correlated. Although the function of DnaK is uncertain, it may improve tolerance to V. campbellii via immune stimulation, a possibility of significance from a fundamental perspective and also because it could be applied in aquaculture, a major method of food production.
    Matched MeSH terms: Adenosine Triphosphatases/biosynthesis*; Bacterial Proteins/biosynthesis*; Molecular Chaperones/biosynthesis*; HSP70 Heat-Shock Proteins/biosynthesis
  19. Cloning, expression, and purification of recombinant protein from a single synthetic multivalent construct of Mycobacterium tuberculosis
    Fang CM, Zainuddin ZF, Musa M, Thong KL
    Protein Expr Purif, 2006 Jun;47(2):341-7.
    PMID: 16510294 DOI: 10.1016/j.pep.2005.12.007
    Tuberculosis remains a major infectious disease with over 8 million new cases and 2 million deaths annually. Therefore, a vaccine more potent than BCG is desperately needed. In this regard, an approximately 800 bp DNA encoding a mycobacterial synthetic gene designated as VacIII (containing ubiquitin gene UbGR and four immunogenic mycobacterial epitopes or genes of ESAT-6, Phos1, Hsp 16.3, and Mtb8.4) was sub-cloned into a bacterial expression vector of pRSET-B resulting in a 6 x His-VacIII fusion gene construction. This recombinant clone was over expressed in Escherichia coli BL-21 (DE-3). The expressed fusion protein was found almost entirely in the insoluble form (inclusion bodies) in cell lysate. The inclusion bodies were solubilized with 8M urea and the recombinant protein was purified by Ni-NTA column and dialyzed by urea gradient dialysis. This method produced a relatively high yield of recombinant VacIII protein and the cloned VacIII gene offers the potential development of other vaccine formats such as DNA vaccine and recombinant vaccine.
    Matched MeSH terms: Antigens, Bacterial/biosynthesis*; Recombinant Fusion Proteins/biosynthesis*; Vaccines, Acellular/biosynthesis; Tuberculosis Vaccines/biosynthesis*
  20. Genome-wide analysis of oral squamous cell carcinomas revealed over expression of ISG15, Nestin and WNT11
    Vincent-Chong VK, Ismail SM, Rahman ZA, Sharifah NA, Anwar A, Pradeep PJ, et al.
    Oral Dis, 2012 Jul;18(5):469-76.
    PMID: 22251088 DOI: 10.1111/j.1601-0825.2011.01894.x
    Multistep pathways and mechanisms are involved in the development of oral cancer. Chromosomal alterations are one of such key mechanisms implicated oral carcinogenesis. Therefore, this study aims to determine the genomic copy number alterations (CNAs) in oral squamous cell carcinoma (OSCC) using array comparative genomic hybridization (aCGH) and in addition attempt to correlate CNAs with modified gene expression.
    Matched MeSH terms: Intermediate Filament Proteins/biosynthesis; Nerve Tissue Proteins/biosynthesis; Ubiquitins/biosynthesis; Cytokines/biosynthesis; Wnt Proteins/biosynthesis
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