Displaying publications 21 - 40 of 4048 in total

Abstract:
Sort:
  1. Sow SL, Khoo G, Chong LK, Smith TJ, Harrison PL, Ong HK
    World J Microbiol Biotechnol, 2014 Oct;30(10):2645-53.
    PMID: 24929362 DOI: 10.1007/s11274-014-1687-z
    In a previous study, notable differences of several physicochemical properties, as well as the community structure of ammonia oxidizing bacteria as judged by 16S rRNA gene analysis, were observed among several disused tin-mining ponds located in the town of Kampar, Malaysia. These variations were associated with the presence of aquatic vegetation as well as past secondary activities that occurred at the ponds. Here, methane oxidizing bacteria (MOB), which are direct participants in the nutrient cycles of aquatic environments and biological indicators of environmental variations, have been characterised via analysis of pmoA functional genes in the same environments. The MOB communities associated with disused tin-mining ponds that were exposed to varying secondary activities were examined in comparison to those in ponds that were left to nature. Comparing the sequence and phylogenetic analysis of the pmoA clone libraries at the different ponds (idle, lotus-cultivated and post-aquaculture), we found pmoA genes indicating the presence of type I and type II MOB at all study sites, but type Ib sequences affiliated with the Methylococcus/Methylocaldum lineage were most ubiquitous (46.7 % of clones). Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture was observed to harbor the highest richness of MOB. However, varying secondary activity or sample type did not show a strong variation in community patterns as compared to the ammonia oxidizers in our previous study.
    Matched MeSH terms: Bacterial Proteins/genetics
  2. Cha TS, Yee W, Aziz A
    World J Microbiol Biotechnol, 2012 Apr;28(4):1771-9.
    PMID: 22805959 DOI: 10.1007/s11274-011-0991-0
    The successful establishment of an Agrobacterium-mediated transformation method and optimisation of six critical parameters known to influence the efficacy of Agrobacterium T-DNA transfer in the unicellular microalga Chlorella vulgaris (UMT-M1) are reported. Agrobacterium tumefaciens strain LBA4404 harbouring the binary vector pCAMBIA1304 containing the gfp:gusA fusion reporter and a hygromycin phosphotransferase (hpt) selectable marker driven by the CaMV35S promoter were used for transformation. Transformation frequency was assessed by monitoring transient β-glucuronidase (GUS) expression 2 days post-infection. It was found that co-cultivation temperature at 24°C, co-cultivation medium at pH 5.5, 3 days of co-cultivation, 150 μM acetosyringone, Agrobacterium density of 1.0 units (OD(600)) and 2 days of pre-culture were optimum variables which produced the highest number of GUS-positive cells (8.8-20.1%) when each of these parameters was optimised individually. Transformation conducted with the combination of all optimal parameters above produced 25.0% of GUS-positive cells, which was almost a threefold increase from 8.9% obtained from un-optimised parameters. Evidence of transformation was further confirmed in 30% of 30 randomly-selected hygromycin B (20 mg L(-1)) resistant colonies by polymerase chain reaction (PCR) using gfp:gusA and hpt-specific primers. The developed transformation method is expected to facilitate the genetic improvement of this commercially-important microalga.
    Matched MeSH terms: Green Fluorescent Proteins/analysis; Green Fluorescent Proteins/genetics
  3. Wong CS, Yin WF, Choo YM, Sam CK, Koh CL, Chan KG
    World J Microbiol Biotechnol, 2012 Feb;28(2):453-61.
    PMID: 22806840 DOI: 10.1007/s11274-011-0836-x
    A chemically defined medium called KGm medium was used to isolate from a sample of sea water a bacterial strain, MW3A, capable of using N-3-oxohexanoyl-L: -homoserine lactone as the sole carbon source. MW3A was clustered closely to Pseudomonas aeruginosa by 16S ribosomal DNA sequence analysis. It degraded both N-acylhomoserine lactones (AHLs) with a 3-oxo group substitution and, less preferably, AHLs with unsubstituted groups at C3 position in the acyl side chain, as determined by Rapid Resolution Liquid Chromatography. Its quiP and pvdQ homologue gene sequences showed high similarities to those of known acylases. Spent supernatant of MW3A harvested at 8-h post inoculation was shown to contain long-chain AHLs when assayed with the biosensor Escherichia coli [pSB1075], and specifically N-dodecanoyl-L: -homoserine lactone and N-3-oxotetradecanoyl-L: -homoserine lactone by high resolution mass spectrometry. Hence, we report here a novel marine P. aeruginosa strain MW3A possessing both quorum-quenching and quorum-sensing properties.
    Matched MeSH terms: Bacterial Proteins/metabolism
  4. Loo JL, Lai OM, Long K, Ghazali HM
    World J Microbiol Biotechnol, 2007 Dec;23(12):1771-8.
    PMID: 27517833 DOI: 10.1007/s11274-007-9427-2
    Mycelium-bound lipase (MBL) was prepared using a strain of Geotrichum candidum isolated from local soil. At the time of maximum lipase activity (54 h), the mycelia to which the lipase was bound were harvested by filtration and centrifugation. Dry MBL was prepared by lyophilizing the mycelia obtained. The yield of MBL was 3.66 g/l with a protein content of 44.11 mg/g. The lipase activity and specific lipase activity were 22.59 and 510 U/g protein, respectively. The moisture content of the MBL was 3.85%. The activity of free (extracellular) lipase in the culture supernatant (after removal of mycelia) was less than 0.2 U/ml. The MBL showed selectivity for oleic acid over palmitic acid during hydrolysis of palm olein, indicating that the lipase from G. candidum displayed high substrate selectivity for unsaturated fatty acid containing a cis-9 double bond, even in crude form. This unique specificity of MBL could be a direct, simple and inexpensive way in the fats and oil industry for the selective hydrolysis or transesterification of cis-9 fatty acid residues in natural triacylglycerols.
    Matched MeSH terms: GTP-Binding Proteins
  5. Khan AH, Bayat H, Rajabibazl M, Sabri S, Rahimpour A
    World J Microbiol Biotechnol, 2017 Jan;33(1):4.
    PMID: 27837408
    Glycosylation represents the most widespread posttranslational modifications, found in a broad spectrum of natural and therapeutic recombinant proteins. It highly affects bioactivity, site-specificity, stability, solubility, immunogenicity, and serum half-life of glycoproteins. Numerous expression hosts including yeasts, insect cells, transgenic plants, and mammalian cells have been explored for synthesizing therapeutic glycoproteins. However, glycosylation profile of eukaryotic expression systems differs from human. Glycosylation strategies have been proposed for humanizing the glycosylation pathways in expression hosts which is the main theme of this review. Besides, we also highlighted the glycosylation potential of protozoan parasites by emphasizing on the mammalian-like glycosylation potential of Leishmania tarentolae known as Leishmania expression system.
    Matched MeSH terms: Recombinant Proteins/metabolism
  6. Eskandari A, Nezhad NG, Leow TC, Rahman MBA, Oslan SN
    World J Microbiol Biotechnol, 2023 Dec 08;40(1):39.
    PMID: 38062216 DOI: 10.1007/s11274-023-03851-6
    Yeasts serve as exceptional hosts in the manufacturing of functional protein engineering and possess industrial or medical utilities. Considerable focus has been directed towards yeast owing to its inherent benefits and recent advancements in this particular cellular host. The Pichia pastoris expression system is widely recognized as a prominent and widely accepted instrument in molecular biology for the purpose of generating recombinant proteins. The advantages of utilizing the P. pastoris system for protein production encompass the proper folding process occurring within the endoplasmic reticulum (ER), as well as the subsequent secretion mediated by Kex2 as a signal peptidase, ultimately leading to the release of recombinant proteins into the extracellular environment of the cell. In addition, within the P. pastoris expression system, the ease of purifying recombinant protein arises from its restricted synthesis of endogenous secretory proteins. Despite its achievements, scientists often encounter persistent challenges when attempting to utilize yeast for the production of recombinant proteins. This review is dedicated to discussing the current achievements in the usage of P. pastoris as an expression host. Furthermore, it sheds light on the strategies employed in the expression system and the optimization and development of the fermentative process of this yeast. Finally, the impediments (such as identifying high expression strains, improving secretion efficiency, and decreasing hyperglycosylation) and successful resolution of certain difficulties are put forth and deliberated upon in order to assist and promote the expression of complex proteins in this prevalent recombinant host.
    Matched MeSH terms: Recombinant Proteins/metabolism
  7. Amjad N, Osman HA, Razak NA, Kassian J, Din J, bin Abdullah N
    World J Gastroenterol, 2010 Sep 21;16(35):4443-7.
    PMID: 20845512
    AIM: To study the presence of Helicobacter pylori (H. pylori) virulence factors and clinical outcome in H. pylori infected patients.

    METHODS: A prospective analysis of ninety nine H. pylori-positive patients who underwent endoscopy in our Endoscopy suite were included in this study. DNA was isolated from antral biopsy samples and the presence of cagA, iceA, and iceA2 genotypes were determined by polymerase chain reaction and a reverse hybridization technique. Screening for H. pylori infection was performed in all patients using the rapid urease test (CLO-Test).

    RESULTS: From a total of 326 patients who underwent endoscopy for upper gastrointestinal symptoms, 99 patients were determined to be H. pylori-positive. Peptic ulceration was seen in 33 patients (33%). The main virulence strain observed in this cohort was the cagA gene isolated in 43 patients. cagA was associated with peptic ulcer pathology in 39.5% (17/43) and in 28% (16/56) of non-ulcer patients. IceA1 was present in 29 patients (29%) and iceA2 in 15 patients (15%). Ulcer pathology was seen in 39% (11/29) of patients with iceA1, while 31% (22/70) had normal findings. The corresponding values for iceA2 were 33% (5/15) and 33% (28/84), respectively.

    CONCLUSION: Virulence factors were not common in our cohort. The incidence of factors cagA, iceA1 and iceA2 were very low although variations were noted in different ethnic groups.

    Matched MeSH terms: Bacterial Outer Membrane Proteins/genetics*; Bacterial Proteins/genetics*
  8. Yeoh LC, Loh CK, Gooi BH, Singh M, Gam LH
    World J Gastroenterol, 2010 Jun 14;16(22):2754-63.
    PMID: 20533595
    AIM: To identify differentially expressed hydrophobic proteins in colorectal cancer.

    METHODS: Eighteen pairs of colorectal cancerous tissues in addition to tissues from normal mucosa were analysed. Hydrophobic proteins were extracted from the tissues, separated using 2-D gel electrophoresis and analysed using Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS). Statistical analysis of the proteins was carried out in order to determine the significance of each protein to colorectal cancer (CRC) and also their relation to CRC stages, grades and patients' gender.

    RESULTS: Thirteen differentially expressed proteins which were expressed abundantly in either cancerous or normal tissues were identified. A number of these proteins were found to relate strongly with a particular stage or grade of CRC. In addition, the association of these proteins with patient gender also appeared to be significant.

    CONCLUSION: Stomatin-like protein 2 was found to be a promising biomarker for CRC, especially in female patients. The differentially expressed proteins identified were associated with CRC and may act as drug target candidates.

    Matched MeSH terms: Blood Proteins/chemistry; Membrane Proteins/chemistry; Neoplasm Proteins/chemistry*
  9. Alfizah H, Rukman AH, Norazah A, Hamizah R, Ramelah M
    World J Gastroenterol, 2013 Feb 28;19(8):1283-91.
    PMID: 23483193 DOI: 10.3748/wjg.v19.i8.1283
    To characterise the cag pathogenicity island in Helicobacter pylori (H. pylori) isolates by analysing the strains' vacA alleles and metronidazole susceptibilities in light of patient ethnicity and clinical outcome.
    Matched MeSH terms: Bacterial Proteins/genetics*
  10. Zahary MN, Kaur G, Abu Hassan MR, Singh H, Naik VR, Ankathil R
    World J Gastroenterol, 2012 Feb 28;18(8):814-20.
    PMID: 22371642 DOI: 10.3748/wjg.v18.i8.814
    To investigate the protein expression profile of mismatch repair (MMR) genes in suspected cases of Lynch syndrome and to characterize the associated germline mutations.
    Matched MeSH terms: Nuclear Proteins/genetics*; Adaptor Proteins, Signal Transducing/genetics*
  11. Yeoh LC, Dharmaraj S, Gooi BH, Singh M, Gam LH
    World J Gastroenterol, 2011 Apr 28;17(16):2096-103.
    PMID: 21547128 DOI: 10.3748/wjg.v17.i16.2096
    To evaluate the usefulness of differentially expressed proteins from colorectal cancer (CRC) tissues for differentiating cancer and normal tissues.
    Matched MeSH terms: Neoplasm Proteins/analysis*
  12. Ahmad Aizat AA, Siti Nurfatimah MS, Aminudin MM, Ankathil R
    World J Gastroenterol, 2013 Jun 21;19(23):3623-8.
    PMID: 23801864 DOI: 10.3748/wjg.v19.i23.3623
    To investigate the risk association of xeroderma pigmentosum group C (XPC) Lys939Gln polymorphism alone and in combination with cigarette smoking on colorectal cancer (CRC) predisposition.
    Matched MeSH terms: DNA-Binding Proteins/genetics*
  13. Gam LH, Leow CH, Man CN, Gooi BH, Singh M
    World J Gastroenterol, 2006 Aug 21;12(31):4973-80.
    PMID: 16937492
    AIM: To identify and analyze the differentially expressed proteins in normal and cancerous tissues of four patients suffering from colon cancer.

    METHODS: Colon tissues (normal and cancerous) were homogenized and the proteins were extracted using three protein extraction buffers. The extraction buffers were used in an orderly sequence of increasing extraction strength for proteins with hydrophobic properties. The protein extracts were separated using the SDS-PAGE method and the images were captured and analyzed using Quantity One software. The target protein bands were subjected to in-gel digestion with trypsin and finally analyzed using an ESI-ion trap mass spectrometer.

    RESULTS: A total of 50 differentially expressed proteins in colonic cancerous and normal tissues were identified.

    CONCLUSION: Many of the identified proteins have been reported to be involved in the progression of similar or other types of cancers. However, some of the identified proteins have not been reported before. In addition, a number of hypothetical proteins were also identified.

    Matched MeSH terms: Neoplasm Proteins/biosynthesis
  14. Sukeepaisarnjaroen W, Pham T, Tanwandee T, Nazareth S, Galhenage S, Mollison L, et al.
    World J Gastroenterol, 2015 Jul 28;21(28):8660-9.
    PMID: 26229408 DOI: 10.3748/wjg.v21.i28.8660
    To examined the efficacy and safety of treatment with boceprevir, PEGylated-interferon and ribavirin (PR) in hepatitis C virus genotype 1 (HCVGT1) PR treatment-failures in Asia.
    Matched MeSH terms: Recombinant Proteins/therapeutic use
  15. Kochuieva M, Psarova V, Ruban L, Kyrychenko N, Alypova O, Matlai O, et al.
    Wiad Lek, 2019 Aug 31;72(8):1484-1498.
    PMID: 32003208
    Introduction: The metabolic syndrome is one of the most discussed cross-disciplinary problems of modern medicine. Now there are various definitions and criteria of diagnostics of metabolic syndrome. The abdominal obesity is considered the main component of the metabolic syndrome, as a reflection of visceral obesity which degree is offered to be estimated on an indirect indicator – a waist circumference. Alongside with abdominal obesity, a number of classifications distinguish insulin resistance (IR) as a diagnostic criterion of metabolic syndrome. It is proved that IR is one of the pathophysiological mechanisms influencing the development and the course of arterial hypertension (AH), type 2 DM and obesity. There are two components in the development of IR: genetic (hereditary) and acquired. In spite of the fact that IR has the accurate genetic predisposition, exact genetic disorders of its appearance have not been identified yet, thus demonstrating its polygenic nature.

    The aim: To establish possible associations of the insulin receptor substrate-1 (IRS-1) gene polymorphism with the severity of the metabolic syndrome components in patients with arterial hypertension (AH).

    Material and methods: 187 patients with AH aged 45-55 years and 30 healthy individuals. Methods: anthropometry, reactive hyperemia, color Doppler mapping, biochemical blood analysis, HOMA-insulin resistance (IR), glucose tolerance test, enzyme immunoassay, molecular genetic method.

    Results: Among hypertensive patients, 103 had abdominal obesity, 43 - type 2 diabetes, 131 - increased blood triglycerides, 19 - decreased high density lipoproteins, 59 - prediabetes (33 - fasting hyperglycemia and 26 - impaired glucose tolerance), 126 had IR. At the same time, hypertensive patients had the following distribution of IRS-1 genotypes: Gly/Gly - 47.9%, Gly/Arg - 42.2% and Arg/Arg - 10.7%, whereas in healthy individuals the distribution of genotypes was significantly different: Gly/Gly - 86.8% (p <0.01), Gly/ Arg - 9.9% (p <0.01) and Arg/Arg - 3.3% (p <0.05). Hypertensive patients with Arg/Arg and Gly/Arg genotypes had significantly higher HOMA-IR (p <0.01), glucose, insulin and triglycerides levels (p <0.05), than in Gly/Gly genotype. At the same time, body mass index, waist circumference, blood pressure, adiponectin, HDL, interleukin-6, C-reactive protein, degree of endothelium-dependent vasodilation, as well as the frequency of occurrence of impaired glucose tolerance did not significantly differ in IRS-1 genotypes.

    Conclusions: In hypertensive patients, the genetic polymorphism of IRS-1 gene is associated with such components of the metabolic syndrome as hypertriglyceridemia and fasting hyperglycemia; it is not associated with proinflammatory state, endothelial dysfunction, dysglycemia, an increase in waist circumference and decrease in HDL.

    Matched MeSH terms: Insulin Receptor Substrate Proteins/genetics*
  16. Alam MZ, Fakhru'l-Razi A, Molla AH
    Water Res, 2003 Sep;37(15):3569-78.
    PMID: 12867323
    The biosolids accumulation and biodegradation of domestic wastewater treatment plant (DWTP) sludge by filamentous fungi have been investigated in a batch fermenter. The filamentous fungi Aspergillus niger and Penicillium corylophilum isolated from wastewater and DWTP sludge was used to evaluate the treatment performance. The optimized mixed inoculum (A. niger and P. corylophilum) and developed process conditions (co-substrate and its concentration, temperature, initial pH, inoculum size, and aeration and agitation rate) were incorporated to accelerate the DWTP sludge treatment process. The results showed that microbial treatment of higher strength of DWTP sludge (4% w/w of TSS) was highly influenced by the liquid state bioconversion (LSB) process. In developed bioconversion processes, 93.8 g/kg of biosolids was enriched with fungal biomass protein of 30 g/kg. Enrichment of nutrients such as nitrogen (N), phosphorous (P), potassium (K) in biosolids was recorded in 6.2% (w/w), 3.1% (w/w) and 0.15% (w/w) from its initial values of 4.8% (w/w), 2.0% (w/w) and 0.08% (w/w) respectively after 10 days of fungal treatment. The biodegradation results revealed that 98.8% of TSS, 98.2% of TDS, 97.3% of turbidity, 80.2% of soluble protein, 98.8% of reducing sugar and 92.7% of COD in treated DWTP sludge supernatant were removed after 8 days of microbial treatment. The specific resistance to filtration (SRF) in treated sludge (1.4x10(12) m/kg) was decreased tremendously by the microbial treatment of DWTP sludge after 6 days of fermentation compared to untreated sample (85x10(12) m/kg).
    Matched MeSH terms: Proteins/metabolism
  17. Hui YW, Narayanan K, Dykes GA
    Water Environ Res, 2016 Nov 01;88(11):2040-2046.
    PMID: 26704787 DOI: 10.2175/106143016X14504669767292
      The effect of physical shearing on the attachment of six Pseudomonas aeruginosa strains and six Burkholderia cepacia strains to glass, stainless steel, polystyrene and Teflon® was determined. A significant (p < 0.05) decrease in hydrophobicity was apparent for all P. aeruginosa strains (17-36%) and B. cepacia, MS 5 (20%) after shearing. A significant (p < 0.05) decrease in attachment of some P. aeruginosa (0.2-0.5 log CFU/cm2) and B. cepacia (0.2-0.4 log CFU/cm2) strains to some surface types was apparent after shearing. Significant (p < 0.05) correlation was observed for both numbers of flagellated cells and hydrophobicity against attachment to glass, stainless steel and polystyrene for P. aeruginosa while only hydrophobicity showed significant correlation against the same surfaces for B. cepacia. Scanning electron microscopy and protein analysis showed that shearing removed surface proteins from the cells and may have led to the observed changes in hydrophobicity and attachment to abiotic surfaces.
    Matched MeSH terms: Membrane Proteins
  18. Tham HW, Balasubramaniam VR, Tejo BA, Ahmad H, Hassan SS
    Viruses, 2014 Dec;6(12):5028-46.
    PMID: 25521592 DOI: 10.3390/v6125028
    Aedes aegypti is a principal vector responsible for the transmission of dengue viruses (DENV). To date, vector control remains the key option for dengue disease management. To develop new vector control strategies, a more comprehensive understanding of the biological interactions between DENV and Ae. aegypti is required. In this study, a cDNA library derived from the midgut of female adult Ae. aegypti was used in yeast two-hybrid (Y2H) screenings against DENV2 envelope (E) protein. Among the many interacting proteins identified, carboxypeptidase B1 (CPB1) was selected, and its biological interaction with E protein in Ae. aegypti primary midgut cells was further validated. Our double immunofluorescent assay showed that CPB1-E interaction occurred in the endoplasmic reticulum (ER) of the Ae. aegypti primary midgut cells. Overexpression of CPB1 in mosquito cells resulted in intracellular DENV2 genomic RNA or virus particle accumulation, with a lower amount of virus release. Therefore, we postulated that in Ae. aegypti midgut cells, CPB1 binds to the E protein deposited on the ER intraluminal membranes and inhibits DENV2 RNA encapsulation, thus inhibiting budding from the ER, and may interfere with immature virus transportation to the trans-Golgi network.
    Matched MeSH terms: Viral Envelope Proteins/genetics; Viral Envelope Proteins/metabolism*; Insect Proteins/genetics; Insect Proteins/metabolism*
  19. Kannan M, Zainal Z, Ismail I, Baharum SN, Bunawan H
    Viruses, 2020 07 26;12(8).
    PMID: 32722532 DOI: 10.3390/v12080803
    Numerous potyvirus studies, including virus biology, transmission, viral protein function, as well as virus-host interaction, have greatly benefited from the utilization of reverse genetic techniques. Reverse genetics of RNA viruses refers to the manipulation of viral genomes, transfection of the modified cDNAs into cells, and the production of live infectious progenies, either wild-type or mutated. Reverse genetic technology provides an opportunity of developing potyviruses into vectors for improving agronomic traits in plants, as a reporter system for tracking virus infection in hosts or a production system for target proteins. Therefore, this review provides an overview on the breakthroughs achieved in potyvirus research through the implementation of reverse genetic systems.
    Matched MeSH terms: Viral Proteins/genetics
  20. Sharma S, Chatterjee A, Kumar P, Lal S, Kondabagil K
    Viruses, 2020 04 15;12(4).
    PMID: 32326380 DOI: 10.3390/v12040444
    Micro RNAs (miRNAs) are a class of small non-coding single-stranded RNA, which play an important role in modulating host-Influenza A virus (IAV) crosstalk. The interplay between influenza and miRNA interaction is defined by a plethora of complex mechanisms, which are not fully understood yet. Here, we demonstrate that in IAV infected A549 cells, a synchronous increase was observed in the expression of mTOR up to 24 hpi and significant downregulation at 48 hpi. Additionally, NP of IAV interacts with mTOR and modulates the levels of mTOR mRNA and protein, thus regulating the translation of host cell. RNA sequencing and qPCR analysis of IAV-infected A549 cells and NP transfected cells revealed that miR-101 downregulates mTOR transcripts at later stages of infection. Ectopic expression of miR-101 mimic led to a decrease in expression of NP, a reduction in IAV titer and replication. Moreover, treatment of the cells with Everolimus, a potent inhibitor of mTOR, resulted in an increase of miR-101 transcript levels, which further suppressed the viral protein synthesis. Collectively, the data suggest a novel mechanism that IAV stimulates mTOR pathway at early stages of infection; however, at a later time-point, positive regulation of miR-101 restrains the mTOR expression, and hence, the viral propagation.
    Matched MeSH terms: Membrane Proteins/metabolism
Filters
Contact Us

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

External Links