Displaying publications 961 - 980 of 4089 in total

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  1. Enhanced secretory production of hemolysin-mediated cyclodextrin glucanotransferase in Escherichia coli by random mutagenesis of the ABC transporter system
    Low KO, Mahadi NM, Abdul Rahim R, Rabu A, Abu Bakar FD, Abdul Murad AM, et al.
    J Biotechnol, 2010 Dec;150(4):453-9.
    PMID: 20959127 DOI: 10.1016/j.jbiotec.2010.10.001
    The hemolysin transport system was found to mediate the release of cyclodextrin glucanotransferase (CGTase) into the extracellular medium when it was fused to the C-terminal 61 amino acids of HlyA (HlyAs(61)). To produce an improved-secretion variant, the hly components (hlyAs, hlyB and hlyD) were engineered by directed evolution using error-prone PCR. Hly mutants were screened on solid LB-starch plate for halo zone larger than the parent strain. Through screening of about 1 × 10(4) Escherichia coli BL21(DE3) transformants, we succeeded in isolating five mutants that showed a 35-217% increase in the secretion level of CGTase-HlyAs(61) relative to the wild-type strain. The mutation sites of each mutant were located at HlyB, primarily along the transmembrane domain, implying that the corresponding region was important for the improved secretion of the target protein. In this study we describe the finding of novel site(s) of HlyB responsible for enhancing secretion of CGTase in E. coli.
    Matched MeSH terms: Hemolysin Proteins/metabolism*; Escherichia coli Proteins/metabolism*
  2. The full-length clone of cucumber green mottle mosaic virus and its application as an expression system for Hepatitis B surface antigen
    Ooi A, Tan S, Mohamed R, Rahman NA, Othman RY
    J Biotechnol, 2006 Feb 24;121(4):471-81.
    PMID: 16271415
    A cucumber green mosaic mottle virus (CGMMV) full-length clone was developed for the expression of Hepatitis B surface antigen (HBsAg). The expression of the surface displayed HBsAg by the chimeric virus was confirmed through a double antibody sandwich ELISA. Assessment of the coat protein composition of the chimeric virus particles by SDS-PAGE analysis showed that 50% of the coat proteins were fused to the HBsAg. Biological activity of the expressed HBsAg was assessed through the stimulation of in vitro antibody production by cultured peripheral blood mononuclear cells (PBMC). PBMC that were cultured in the presence of the chimeric virus showed up to an approximately three-fold increase in the level of anti HBsAg immunoglobulin thus suggesting the possible use of this new chimeric virus as an effective Hepatitis B vaccine.
    Matched MeSH terms: Recombinant Proteins/biosynthesis*; Recombinant Proteins/genetics; Recombinant Proteins/immunology
  3. Synthesis of conjugated linoleic acid-rich triacylglycerols by immobilized mutant lipase with excellent capability and recyclability
    Lian W, Li D, Zhang L, Wang W, Faiza M, Tan CP, et al.
    Enzyme Microb Technol, 2018 Oct;117:56-63.
    PMID: 30037552 DOI: 10.1016/j.enzmictec.2018.06.007
    Conjugated linoleic acid (CLA)-rich triacylglycerols (TAG) have received significant attention owing to their health promoting properties. In this study, CLA-rich TAG were successfully synthesized by an immobilized mutant lipase (MAS1-H108A)-catalyzed esterification of CLA-rich fatty acids and glycerol under vacuum. MAS1-H108A was first immobilized onto ECR1030 resin. Results showed that the lipase/support ratio of 41 mg/g was suitable for the immobilization and the thermostability of immobilized MAS1-H108A was greatly enhanced. Subsequently, the immobilized MAS1-H108A was employed for the synthesis of CLA-rich TAG and 95.21% TAG with 69.19% CLA was obtained under the optimized conditions. The TAG content (95.21%) obtained by immobilized MAS1-H108A is the reported highest value thus far, which was significantly higher than that (9.26%) obtained by Novozym 435 under the same conditions. Although the TAG content comparable to the results obtained in this study could also be obtained by Novozym 435, the used enzyme amount is approximately 5-fold of the immobilized MAS1-H108A. Additionally, the immobilized MAS1-H108A exhibited excellent recyclability during esterification retaining 95.11% of its initial activity after 10 batches. Overall, such immobilized mutant lipase with superior esterification activity and recyclability has the potential to be used in oils and fats industry.
    Matched MeSH terms: Fungal Proteins/genetics; Fungal Proteins/metabolism*; Fungal Proteins/chemistry
  4. Fulltext Dose-and time-dependent suppression of Rac1 and STIM1 in acute myeloid leukaemia cell line model
    Eman S. Algariri, Rabiatul Basria S.M.N. Mydin, Emmanuel Jairaj Moses, Simon Imakwu Okekpa, Nur Arzuar Abdul Rahim, Narazah Mohd Yusoff
    Malaysian Journal of Medicine and Health Sciences, 2020;16(3):238-242.
    MyJurnal
    Introduction: Rac1 and STIM1 genes are emerging therapeutic targets for cancers. However, their roles in acute my- eloid leukaemia (AML) are not well understood. The goal of this study was to evaluate the effects of dose and time on Rac1 and STIM1 knockdown in the AML cell line model (THP-1 cells). Methods: THP-1 cells were transfected with siRac1 at doses of 50, 100, and 200 nM or dsiSTIM1 at doses of 2, 5, and 10 nM. Expression level of Rac1 and STIM1 then were assessed at time points between 12 and 72 h post-transfection using real-time reverse transcription poly- merase chain reaction. Results: Compared to the control, 87% Rac1 knockdown was attained with 50 nM siRac1 at 24 h post-transfection, and 70% STIM1 knockdown was achieved with 10 nM dsiSTIM1 at 48 h post-transfection. Conclusion: These results show that effective knockdown of Rac1 and STIM1 is possible, and therapy that includes Rac1 and STIM1 inhibitors eventually could provide a new and highly effective strategy for AML treatment.
    Matched MeSH terms: Neoplasm Proteins
  5. Role of the cell envelope in the antibacterial activities of polymyxin B and polymyxin B nonapeptide against Escherichia coli
    Sahalan AZ, Dixon RA
    Int J Antimicrob Agents, 2008 Mar;31(3):224-7.
    PMID: 18083010
    The role of membrane permeabilisation and disruption in the mechanism of action of some polymyxin analogues against Gram-negative organisms is contentious. The effects of polymyxin B (PMB) and its analogue polymyxin B nonapeptide (PMBN) on Escherichia coli envelopes should correlate, but previous work by other workers suggests that PMBN has a different mode of action. This study has reassessed the biochemical techniques used previously and has shown that, in contrast to previous studies, PMBN (a well-characterised antibacterial synergist) readily releases periplasmic proteins and lipopolysaccharide from treated E. coli at subinhibitory concentrations in normal physiological buffer conditions. We conclude that, when tested with appropriate methodology, PMBN closely correlates with the early effects of PMB on the cell envelope of E. coli and this study shows that it is now consistent with the accepted interactions of membrane-active agents against Gram-negative cells.
    Matched MeSH terms: Escherichia coli Proteins/metabolism; Periplasmic Proteins/metabolism
  6. Epitope mapping of the Sta58 major outer membrane protein of Rickettsia tsutsugamushi
    Lachumanan R, Devi S, Cheong YM, Rodda SJ, Pang T
    Infect Immun, 1993 Oct;61(10):4527-31.
    PMID: 7691753
    Binding studies of 160 overlapping, synthetic octapeptides from the hydrophilic regions of the Sta58 major outer membrane protein of Rickettsia tsutsugamushi with sera from patients with scrub typhus revealed 15 immunodominant peptides which are recognized by all the sera tested. Further analysis of the specificity of peptide binding with five of these peptides indicated that the peptides showed significantly stronger binding to scrub typhus patients' sera than they did to sera from patients with other febrile illnesses common in the region, i.e., malaria, dengue fever, typhoid fever, and leptospirosis. The main antibody class binding to these peptides appears to be immunoglobulin M, and there appears to be little correlation between reactivity with peptides and antibody titers measured by the indirect immunoperoxidase test.
    Matched MeSH terms: Bacterial Outer Membrane Proteins/immunology*; Bacterial Proteins/immunology*
  7. Fulltext Evaluation of CERS2 Gene as a Potential Biomarker for Bladder Cancer
    Aldoghachi AF, Baharudin A, Ahmad U, Chan SC, Ong TA, Yunus R, et al.
    Dis Markers, 2019;2019:3875147.
    PMID: 31636736 DOI: 10.1155/2019/3875147
    The ceramide synthase 2 (CERS2) gene has been linked to tumour recurrence and invasion in many different types of cancers including bladder cancer. In this study, the expression levels of CERS2 in bladder cancer cell lines were analysed using qRT-PCR and the protein expression in clinical bladder cancer histopathological specimens were examined via immunohistochemistry. The potential utility of CERS2 as a predictive biomarker of response to oncolytic virotherapy was assessed by correlating the CERS2 mRNA expression to IC50 values of cells treated with the Newcastle disease virus (NDV), AF2240 strain. This study demonstrates that CERS2 is differentially expressed in different types of bladder cancer cell lines and that the siRNA-mediated downregulation of the expression of CERS2 reduces the migratory potential of UMUC1 bladder cancer cells. However, there were no significant correlations between the expression levels of the CERS2 protein with bladder cancer grade/stage or between the IC50 values of cells treated with NDV and CERS2 expression. Although the utility of CERS2 expression may be limited, its potential as an antimigration cancer therapeutic should be further examined.
    Matched MeSH terms: Membrane Proteins/metabolism*; Tumor Suppressor Proteins/metabolism*
  8. First molecular genotyping of insensitive acetylcholinesterase associated with malathion resistance in Culex quinquefasciatus Say populations in Malaysia
    Low VL, Chen CD, Lim PE, Lee HL, Lim YA, Tan TK, et al.
    Pest Manag Sci, 2013 Dec;69(12):1362-8.
    PMID: 23404830 DOI: 10.1002/ps.3512
    Given that there is limited available information on the insensitive acetylcholinesterase in insect species in Malaysia, the present study aims to detect the presence of G119S mutation in the acetylcholinesterase gene of Culex quinquefasciatus from 14 residential areas across 13 states and a federal territory in Malaysia.
    Matched MeSH terms: Insect Proteins/antagonists & inhibitors; Insect Proteins/genetics*; Insect Proteins/metabolism
  9. In silico and saturation transfer difference NMR approaches to unravel the binding mode of an andrographolide derivative to K-Ras oncoprotein
    Quah SY, Tan MS, Ho KL, Manan NA, Gorfe AA, Deb PK, et al.
    Future Med Chem, 2020 09;12(18):1611-1631.
    PMID: 32892640 DOI: 10.4155/fmc-2020-0104
    Background: Andrographolide and its benzylidene derivatives, SRJ09 and SRJ23, potentially bind oncogenic K-Ras to exert anticancer activity. Their molecular interactions with K-Ras oncoproteins that lead to effective biological activity are of major interest. Methods & results: In silico docking and molecular dynamics simulation were performed using Glide and Desmond, respectively; while saturation transfer difference NMR was performed using GDP-bound K-RasG12V. SRJ23 was found to bind strongly and selectively to K-RasG12V, by anchoring to a binding pocket (namely p2) principally via hydrogen bond and hydrophobic interactions. The saturation transfer difference NMR analysis revealed the proximity of protons of functional moieties in SRJ23 to K-RasG12V, suggesting positive binding. Conclusion: SRJ23 binds strongly and interacts stably with K-RasG12V to exhibit its inhibitory activity.
  10. Fulltext Mutation-specific pathophysiological mechanisms define different neurodevelopmental disorders associated with SATB1 dysfunction
    den Hoed J, de Boer E, Voisin N, Dingemans AJM, Guex N, Wiel L, et al.
    Am J Hum Genet, 2021 02 04;108(2):346-356.
    PMID: 33513338 DOI: 10.1016/j.ajhg.2021.01.007
    Whereas large-scale statistical analyses can robustly identify disease-gene relationships, they do not accurately capture genotype-phenotype correlations or disease mechanisms. We use multiple lines of independent evidence to show that different variant types in a single gene, SATB1, cause clinically overlapping but distinct neurodevelopmental disorders. Clinical evaluation of 42 individuals carrying SATB1 variants identified overt genotype-phenotype relationships, associated with different pathophysiological mechanisms, established by functional assays. Missense variants in the CUT1 and CUT2 DNA-binding domains result in stronger chromatin binding, increased transcriptional repression, and a severe phenotype. In contrast, variants predicted to result in haploinsufficiency are associated with a milder clinical presentation. A similarly mild phenotype is observed for individuals with premature protein truncating variants that escape nonsense-mediated decay, which are transcriptionally active but mislocalized in the cell. Our results suggest that in-depth mutation-specific genotype-phenotype studies are essential to capture full disease complexity and to explain phenotypic variability.
    Matched MeSH terms: Matrix Attachment Region Binding Proteins/genetics*; Matrix Attachment Region Binding Proteins/metabolism; Matrix Attachment Region Binding Proteins/chemistry
  11. Fulltext Efficiency of different sampling tools for aquatic macroinvertebrate collections in Malaysian streams
    Wan Mohd Hafezul Wan Abdul Ghani, Che Salmah Md Rawi, Suhaila Abd. Hamid, Al-Shami, Salman Abdo
    Trop Life Sci Res, 2016;27(1):115-133.
    MyJurnal
    This study analyses the sampling performance of three benthic sampling tools
    commonly used to collect freshwater macroinvertebrates. Efficiency of qualitative D-frame
    and square aquatic nets were compared to a quantitative Surber sampler in tropical
    Malaysian streams. The abundance and diversity of macroinvertebrates collected using
    each tool evaluated along with their relative variations (RVs). Each tool was used to
    sample macroinvertebrates from three streams draining different areas: a vegetable farm,
    a tea plantation and a forest reserve. High macroinvertebrate diversities were recorded using the square net and Surber sampler at the forested stream site; however, very low
    species abundance was recorded by the Surber sampler. Relatively large variations in the
    Surber sampler collections (RVs of 36% and 28%) were observed for the vegetable farm
    and tea plantation streams, respectively. Of the three sampling methods, the square net
    was the most efficient, collecting a greater diversity of macroinvertebrate taxa and a
    greater number of specimens (i.e., abundance) overall, particularly from the vegetable
    farm and the tea plantation streams (RV
    Matched MeSH terms: Norepinephrine Plasma Membrane Transport Proteins
  12. Fulltext Bird species composition and feeding guilds based on point count and mist netting methods at the Paya Indah Wetland Reserve, Peninsular Malaysia
    Mohamed Zakaria, Muhammad Nawaz Rajpar
    Trop Life Sci Res, 2010;21(2):-.
    MyJurnal
    A comparison study was conducted to determine the bird species composition, relative abundance, species diversity and feeding guilds based on point count (PC) and mist netting (MN) at the Paya Indah Wetland Reserve (PIWR), Peninsular Malaysia. A total of 13872 bird observations belonging to 100 species and 38 families were recorded using the PC method over 15 consecutive months, and a total of 1478 bird individuals
    belonging to 65 species and 33 families were captured using the MN method over 1260 netting hours. The results showed that Treron vernans (1723 observations; 12.42%) was the most abundant bird species using the PC method, whereas Pycnonotus goiavier (378 individuals; 25.64%) was the most abundant bird species using the MN method. The Ardeidae (9 species; 23.68%) was the most dominant family using the PC method, but the Rallidae (6 species; 18.18%) was the most dominant family using the MN method. The PC method produced higher species diversity (Shannon’s N1 = 31.22) and richness (Margalef’s R1 = 10.42) than MN, whereas the MN method produced higher species evenness (McIntosh’s E = 0.86) than the PC method. Frugivore/insectivore comprised of bulbuls, orioles, pigeons and starlings was the most dominant feeding guild in both methods (PC = 27.81% and MN = 32.88%). In contrast, carnivore was the rarest feeding guild in both methods (i.e. PC = 0.17% and MN = 0.20%). These findings indicate that the PC method is more efficient and produces better results than the MN method.
    Matched MeSH terms: Norepinephrine Plasma Membrane Transport Proteins
  13. Fulltext Conchology Variations in Species Identification of Pachychilidae (Mollusca, Gastropoda, Cerithiodea) through Multivariate Analysis
    Hamli H, Hamed NA, Azmai SHS, Idris MH
    Trop Life Sci Res, 2020 Jul;31(2):145-158.
    PMID: 32922672 DOI: 10.21315/tlsr2020.31.2.7
    Pachychilidae is one of the freshwater gastropod family which was previously known under the Potamididae and Thiaridae families. Studies on freshwater gastropods especially on conchcology examinantions are still inadequate compared to marine gastropods. Morphological and morphometric studies of gastropods are practically used to identify and differentiate between species and necessary to complement molecular studies due to its low cost and tolerable resolving power of discrimination. The aim of the current study is to provide information on morphological and morphometric characteristics of Pachychilidae in Bintulu, Sarawak stream. A total of 20 individuals from each species of Sulcospira testudinaria, Sulcospira schmidti, Brotia siamensis, and Tylomelania sp. from Pachychilidae familiy were collected at three different sites from a small stream within the Bintulu area. Fourteen measurement of shell morphometrics were converted into proportioned ratios and analysed for univariate and multivariate analysis. Three shell morphometric (Aperture width, AW; Whorl width, WW2; and, Interior anterior length, AINL) of Pachychilidae indicated significant differences (P < 0.05) between species. However, multivariate analysis revealed that these shell morphometrics are pre-eminent factors to discriminate genus Sulcospira, Brotia and Tylomelania, as well as between Sulcospira species. This current study also suggests that these three characteristics are unique to Sulcospira species due to strong distinction among species. Findings on these three characteristics are significant for Sulcospira spp. as this study is the first shell morphometric report on the Pachychilidae species in Sarawak.
    Matched MeSH terms: Complement System Proteins
  14. CIP2A expression in high grade prostatic intraepithelial neoplasia and prostate adenocarcinoma: a tissue mıcroarray study
    Celikden SG, Baspinar S, Ozturk SA, Karaibrahimoglu A
    Malays J Pathol, 2020 Aug;42(2):227-236.
    PMID: 32860375
    INTRODUCTION: CIP2A is an oncoprotein involved in the progression of several human malignancies. It has recently been described as a prognostic marker in many cancers. The present study aimed to investigate the immunohistochemical expression of CIP2A in benign prostatic hyperplasia (BPH), high grade prostatic intraepithelial neoplasia (HGPIN) and prostate cancer (PC), and to analyse the association with the clinicopathological parameters in PC cases to define its role in the development and progression of PC.

    MATERIALS AND METHODS: Immunohistochemical staining for CIP2A was performed on the tissue microarray sections of 105 PC, 27 HGPIN and 27 BPH tissues. The CIP2A expression scores were compared with several clinicopathological parameters.

    RESULTS: CIP2A was expressed in 96,2% of PC, 55,6% of HGPIN and 40,7% of BPH tissues. The expression of CIP2A in PC was significantly higher than in HGPIN (p<0.0001) and BPH (p<0.0001) cases. CIP2A expression score was significantly associated with Gleason score (p=0.032) and lymphovascular invasion (p=0.039). Nevertheless, there was no statistically significant association between the expression of CIP2A and perineural invasion, pT stage, metastasis and recurrence (p>0.05). Multivariate analysis indicated that GS, lymphovascular invasion, distant metastasis were independent prognostic factors for PC patients but, CIP2A expression score was not found to be a prognostic factor. Additionally, there was no significant difference between the survival times of patients according to CIP2A expression (p=0.174).

    CONCLUSIONS: According to our results, the expression of CIP2A protein is increased in PC and its expression may be involved in the development, differentiation, and aggressiveness of PC. However, further studies are needed to confirm our findings and to clarify the role of CIP2A in the development of PC.

    Matched MeSH terms: Membrane Proteins/metabolism*; Intracellular Signaling Peptides and Proteins/metabolism*
  15. Development and structural characterisation of human scFv targeting MDM2 spliced variant MDM215kDa
    Lim CC, Chan SK, Lim YY, Ishikawa Y, Choong YS, Nagaoka Y, et al.
    Mol Immunol, 2021 07;135:191-203.
    PMID: 33930714 DOI: 10.1016/j.molimm.2021.04.016
    The murine double minute 2 (MDM2) protein is a major negative regulator of the tumour suppressor protein p53. Under normal conditions, MDM2 constantly binds to p53 transactivation domain and/or ubiquinates p53 via its role as E3 ubiquitin ligase to promote p53 degradation as well as nuclear export to maintain p53 levels in cells. Meanwhile, amplification of MDM2 and appearance of MDM2 spliced variants occur in many tumours and normal tissues making it a prognostic indicator for human cancers. The mutation or deletion of p53 protein in half of human cancers inactivates its tumour suppressor activity. However, cancers with wild type p53 have its function effectively inhibited through direct interaction with MDM2 oncoprotein. Here, we described the construction of a MDM2 spliced variant (rMDM215kDa) consisting of SWIB/MDM2 domain and its central region for antibody generation. Biopanning with a human naïve scFv library generated four scFv clones specific to rMDM215kDa. Additionally, the selected scFv clones were able to bind to the recombinant full length MDM2 (rMDM2-FL). Computational prediction showed that the selected scFv clones potentially bind to exon 7-8 of MDM2 while leaving the MDM2/SWIB domain free for p53 interaction. The developed antibodies exhibit good specificity can be further investigated for downstream biomedical and research applications.
    Matched MeSH terms: Proto-Oncogene Proteins c-mdm2/genetics*; Proto-Oncogene Proteins c-mdm2/immunology*; Proto-Oncogene Proteins c-mdm2/metabolism
  16. Fulltext Regulation of Proteolytic Activity to Improve the Recovery of Macrobrachium rosenbergii Nodavirus Capsid Protein
    Selvaraj BA, Mariatulqabtiah AR, Ho KL, Ng CL, Yong CY, Tan WS
    Int J Mol Sci, 2021 Aug 13;22(16).
    PMID: 34445426 DOI: 10.3390/ijms22168725
    The causative agent of white tail disease (WTD) in the giant freshwater prawn is Macrobrachium rosenbergii nodavirus (MrNV). The recombinant capsid protein (CP) of MrNV was previously expressed in Escherichia coli, and it self-assembled into icosahedral virus-like particles (VLPs) with a diameter of approximately 30 nm. Extensive studies on the MrNV CP VLPs have attracted widespread attention in their potential applications as biological nano-containers for targeted drug delivery and antigen display scaffolds for vaccine developments. Despite their advantageous features, the recombinant MrNV CP VLPs produced in E. coli are seriously affected by protease degradations, which significantly affect the yield and stability of the VLPs. Therefore, the aim of this study is to enhance the stability of MrNV CP by modulating the protease degradation activity. Edman degradation amino acid sequencing revealed that the proteolytic cleavage occurred at arginine 26 of the MrNV CP. The potential proteases responsible for the degradation were predicted in silico using the Peptidecutter, Expasy. To circumvent proteolysis, specific protease inhibitors (PMSF, AEBSF and E-64) were tested to reduce the degradation rates. Modulation of proteolytic activity demonstrated that a cysteine protease was responsible for the MrNV CP degradation. The addition of E-64, a cysteine protease inhibitor, remarkably improved the yield of MrNV CP by 2.3-fold compared to the control. This innovative approach generates an economical method to improve the scalability of MrNV CP VLPs using individual protease inhibitors, enabling the protein to retain their structural integrity and stability for prominent downstream applications including drug delivery and vaccine development.
    Matched MeSH terms: Capsid Proteins/genetics*; Capsid Proteins/metabolism*; Capsid Proteins/chemistry
  17. Fulltext Differential scanning calorimetry as tool in observing thermal and storage stability of recombinant bromelain
    Nurul, A.I., Azura, A.
    International Food Research Journal, 2012;19(2):727-731.
    MyJurnal
    Knowledge about the thermal and storage behavior of produced protein is important for the purpose of storage, transport and shelve life during industrial application. Recombinant bromelain thermal and storage stability were measured and compared to the commercial bromelain using Differential Scanning Calorimetry (DSC). Recombinant bromelain is more stable than commercial bromelain at higher temperature but the stability was reduced after 7 days of storage at 4oC. Higher energy is needed to break the bond between amino acid chains in recombinant bromelain as shown by the enthalpy obtained, suggesting that recombinant bromelain has good protein structure and conformation compared to commercial.
    Matched MeSH terms: Proteins
  18. Pembuktian dan pengukuhan teori "The New Malay Homeland" berdasarkan rekonstruksi dan klasifikasi bahasa Iban purba Sarawak
    Rahim Aman, Muhammad. Nur Latif
    CREAM : Current Research in Malaysia (Penyelidikan Terkini di Malaysia), 2012;1(1):51-72.
    MyJurnal
    Kajian ini untuk menunjukkan bahawa penentuan tanah air umat Melayu perlu dilihat dalam perspektif pendekatan atau teori yang baru, yakni teori 'The New Malay Homeland'. Ahli Linguistik sejarah pada abad ke-20 dan pada abad ini, iaitu pada abad ke-21 banyak telah melakukan kajian untuk membuktikan bahawa sebenarnya umat Melayu bukan bermigrasi daripada Yunan, sebaliknya daripada Taiwan dan kemudiannya menjadikan Borneo sebagai tanah air kedua umat Melayu. Untuk menjitukan lagi teori ini, maka kajian rekonstruksi dan klasifikasi bahasa Iban di Sarawak dilakukan agar maklumat-maklumat fosil linguistik yang wujud dalam bahasa Iban pada peringkat purbanya dapat membuktikan dan memperkukuhkan hujah bahawa teori di atas adalah benar. Dua kaedah kajian diaplikasi dalam penelitian ini, iaitu kaedah kepustakaan dan kaedah lapangan. Kaedah kajian kepustakaan lebih melihat kepada aspek pembacaan untuk mendapatkan maklumat berkaitan bidang kajian. Kajian-kajian awal ke atas bahasa Iban sejak abad ke-18 sehinga abad ke-21 telah diselidiki. Maklumat berkaitan bidang ilmu linguistik bandingan juga telah dibaca secara seksama. Berkaitan kaedah kajian lapangan, metode semak dan metode cakap dengan pengaplikasian teknik-teknik khas telah dilakukan. Berdasarkan lokasi kajian, tujuh varian bahasa Iban telah diteliti, yakni varian Iban Sri Aman (SA), Betong (BTG), Sarikei (SKEI), Sibu (SBU), Kapit (KPT), Bintulu (BTL) dan Limbang (LMBG) . Hasil penelitian menunjukkan bahawa bahasa Iban Purba Sarawak (IPS) memiliki enam fonem vokal *a, *a, *i, *u, *e, *o; tiga diftong *-uy, *-ay, *-aw dan sembilan belas konsonan, iaitu *p, *b, *t, *d, *k, *g, */, *s, *h, *1, *r, *m, *n, *0, *N, *dZ, *tS, *w, dan *y. Beberapa inovasi fonologi juga diperoleh apabila perbandingan dilakukan antara IPS dengan Bahasa Melayik Purba (BMP), iaitu i) BMP *h > IPS */; ii) BMP *-d > IPS *zero, iii) BMP *-g > IPS *zero, iv), dan BMP *r, *1 > IPS *r. Pada tahap morfologi wujud inovasi dan retensi antara IPS dan BMP, iaitu BMP *ni/di > IPS *ba/ dan morfem BMP *{une (N)}, *{be(R)} dan *ite(R)1 diretensi sepenuhnya dalam IPS. Berdasarkan dapatan daripada kajian ini membuktikan bahawa terdapat ikatan rapat antara BMP dengan IPS dapatan ini juga membuktikan bahawa Borneo adalah tanah air kedua umat Melayu setelah umat ini bermigrasi keluar daripada Taiwan.
    Matched MeSH terms: Bone Morphogenetic Proteins
  19. Response Surface Methodology Modelling of an Aqueous Two-Phase System for Purification of Protease from Penicillium candidum (PCA 1/TT031) under Solid State Fermentation and Its Biochemical Characterization
    Alhelli AM, Abdul Manap MY, Mohammed AS, Mirhosseini H, Suliman E, Shad Z, et al.
    Int J Mol Sci, 2016 Nov 11;17(11).
    PMID: 27845736
    Penicillium candidum (PCA 1/TT031) synthesizes different types of extracellular proteases. The objective of this study is to optimize polyethylene glycol (PEG)/citrate based on an aqueous two-phase system (ATPS) and Response Surface Methodology (RSM) to purify protease from Penicillium candidum (PCA 1/TT031). The effects of different PEG molecular weights (1500-10,000 g/mol), PEG concentration (9%-20%), concentrations of NaCl (0%-10%) and the citrate buffer (8%-16%) on protease were also studied. The best protease purification could be achieved under the conditions of 9.0% (w/w) PEG 8000, 5.2% NaCl, and 15.9% sodium citrate concentration, which resulted in a one-sided protease partitioning for the bottom phase with a partition coefficient of 0.2, a 6.8-fold protease purification factor, and a yield of 93%. The response surface models displayed a significant (p ≤ 0.05) response which was fit for the variables that were studied as well as a high coefficient of determination (R²). Similarly, the predicted and observed values displayed no significant (p > 0.05) differences. In addition, our enzyme characterization study revealed that Penicillium candidum (PCA 1/TT031) produced a slight neutral protease with a molecular weight between 100 and 140 kDa. The optimal activity of the purified enzyme occurred at a pH of 6.0 and at a temperature of 50 °C. The stability between different pH and temperature ranges along with the effect of chemical metal ions and inhibitors were also studied. Our results reveal that the purified enzyme could be used in the dairy industry such as in accelerated cheese ripening.
    Matched MeSH terms: Fungal Proteins/antagonists & inhibitors; Fungal Proteins/isolation & purification*; Fungal Proteins/chemistry
  20. Fulltext A High-Yield Two-Hour Protocol for Extraction of Human Hair Shaft Proteins
    Wong SY, Lee CC, Ashrafzadeh A, Junit SM, Abrahim N, Hashim OH
    PLoS One, 2016;11(10):e0164993.
    PMID: 27741315 DOI: 10.1371/journal.pone.0164993
    Proteome analysis of the human hair remains challenging due to the poor solubility of hair proteins and the difficulty in their extraction. In the present study, we have developed a rapid extraction protocol for hair shaft protein using alkaline-based buffer. The new protocol accelerated the procedure by reducing the extraction time from at least a day to less than two hours and showed a protein recovery of 47.3 ± 3.72%. Further analyses of the extracted protein sample through sodium dodecyl sulfate polyacrylamide gel electrophoresis and Quadrupole-time-of-flight mass spectrometry analysis unveiled a total of 60 proteins, including 25 that were not previously reported. Identification of these proteins is anticipated to be crucial in helping to understand the molecular basis of hair for potential applications in the future.
    Matched MeSH terms: Proteins/analysis*; Proteins/isolation & purification; Proteins/metabolism
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