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  1. Human topoisomerase II alpha as a prognostic biomarker in cancer chemotherapy
    Ali Y, Abd Hamid S
    Tumour Biol., 2016 Jan;37(1):47-55.
    PMID: 26482620 DOI: 10.1007/s13277-015-4270-9
    Topoisomerases are nuclear enzymes that regulate topology of DNA by facilitating the temporary cleavage and ligation cycle of DNA. Among all forms of topoisomerases, TOP-IIA is extensively associated with cell proliferation and therefore is an important therapeutic target in diseases that involved cellular proliferation such as cancers. Nearly half of present-day antitumor regimens contain at least one prescription that act as a topoisomerase inhibitor. Generally, tumor cells show divergent expression of TOP-IIA compared to normal cells. The remarkable expression of TOP-IIA in various carcinomas provides a significant biomarker toward understanding the nature of malignancy. TOP-IIA expression and amplification studies help in diagnosing cancer and to observe the disease progression, overall survival (OS) of patients, and response to therapy. This review highlights the research output and analysis in exploring the standing of TOP-IIA in various carcinomas. As some reports show contradiction within the same field of interest, the outline of that may help to induce researchers for further investigation and clarification. To the best of our knowledge, this is the first overview briefly summarizing the prognostic feature of TOP-IIA in various types of cancer.
    Matched MeSH terms: DNA-Binding Proteins/metabolism*
  2. Organic-solvent stability of elastase strain K overexpressed in an Escherichia-Pseudomonas expression system
    Wong CF, Salleh AB, Basri M, Abd Rahman RN
    Biotechnol Appl Biochem, 2010 Sep;57(1):1-7.
    PMID: 20726840 DOI: 10.1042/BA20100224
    The structural gene of elastase strain K (elastase from Pseudomonas aeruginosa strain K), namely HindIII1500PstI, was successfully sequenced to contain 1497 bp. The amino acid sequence, deduced from the nucleotide sequence, revealed that the mature elastase consists of 301 amino acids, with a molecular mass of 33.1 kDa, and contains a conserved motif HEXXH, zinc ligands and residues involved in the catalysis of elastase strain K. The structural gene was successfully cloned to a shuttle vector, pUCP19, and transformed into Escherichia coli strains TOP10, KRX, JM109 and Tuner™ pLacI as well as P. aeruginosa strains PA01 (A.T.C.C. 47085) and S5, with detection of significant protein expression. Overexpression was detected from transformants KRX/pUCP19/HindIII1500PstI of E. coli and PA01/pUCP19/HindIII1500PstI of P. aeruginosa, with increases in elastolytic activity to 13.83- and 5.04-fold respectively relative to their controls. In addition, recombinant elastase strain K showed considerable stability towards numerous organic solvents such as methanol, ethanol, acetone, toluene, undecan-1-ol and n-dodecane, which typically pose a detrimental effect on enzymes; our finding provides further information to support the potential application of the enzyme in synthetic industries, particularly peptide synthesis.
    Matched MeSH terms: Recombinant Proteins/metabolism
  3. Sago pith residue as an alternative cheap substrate for fermentable sugars production
    Linggang S, Phang LY, Wasoh MH, Abd-Aziz S
    Appl Biochem Biotechnol, 2012 May;167(1):122-31.
    PMID: 22528646 DOI: 10.1007/s12010-012-9592-0
    Sago pith residue is one of the most abundant lignocellulosic biomass which can serve as an alternative cheap substrate for fermentable sugars production. This residue is the fibrous waste left behind after the starch extraction process and contains significant amounts of starch (58%), cellulose (23%), hemicellulose (9.2%) and lignin (3.9%). The conversion of sago pith residue into fermentable sugars is commonly performed using cellulolytic enzymes or known as cellulases. In this study, crude cellulases were produced by two local isolates, Trichoderma asperellum UPM1 and Aspergillus fumigatus, UPM2 using sago pith residue as substrate. A. fumigatus UPM2 gave the highest FPase, CMCase and β-glucosidase activities of 0.39, 23.99 and 0.78 U/ml, respectively, on day 5. The highest activity of FPase, CMCase and β-glucosidase by T. asperellum UPM1 was 0.27, 12.03 and 0.42 U/ml, respectively, on day 7. The crude enzyme obtained from A. fumigatus UPM2 using β-glucosidase as the rate-limiting enzyme (3.9, 11.7 and 23.4 IU) was used for the saccharification process to convert 5% (w/v) sago pith residue into reducing sugars. Hydrolysis of sago pith residue using crude enzyme containing β-glucosidase with 23.4 IU, produced by A. fumigatus UPM2 gave higher reducing sugars production of 20.77 g/l with overall hydrolysis percentage of 73%.
    Matched MeSH terms: Fungal Proteins/metabolism*
  4. Fulltext Anti-ulcerogenic activity of dentatin from clausena excavata Burm.f. against ethanol-induced gastric ulcer in rats: Possible role of mucus and anti-oxidant effect
    Sidahmed HMA, Vadivelu J, Loke MF, Arbab IA, Abdul B, Sukari MA, et al.
    Phytomedicine, 2019 Mar 01;55:31-39.
    PMID: 30668441 DOI: 10.1016/j.phymed.2018.06.036
    BACKGROUND: Clausena excavata Burm.f. (Rutaceae) has been used for the treatment of stomach disorders including peptic ulcer.

    PURPOSE: In this study, we aimed to investigate dentatin isolated from C. excavata Burm.f., for anti-ulcer activity against ethanol ulcer model in rats.

    METHODS: Gastric acid output, ulcer index, serum profile, histological evaluation using Hematoxylin and eosin (HE), periodic acid Schiff base stainings and immunohistochemical localization for heat shock proteins 70 (HSP70) were all investigated. Possible involvement of reduced glutathione (GSH), lipid peroxidation, prostaglandin E2 (PGE2), superoxide dismutase (SOD) enzymes, radical scavenging, and anti-Helicobacter pylori activity were investigated.

    RESULTS: Dentatin showed anti-secretory activity against the pylorus ligature model and protected the gastric mucosa from ethanol ulceration, as revealed by the improved macroscopic and histological appearance. Dentatin significantly increased the gastric homogenate content of PGE2 GSH and SOD. Dentatin inhibited the lipid peroxidation as revealed by the reduced gastric content of malondialdehyde (MDA). Moreover, dentatin up-regulated HSP70 expression. However, dentatin showed insignificant anti-H. pylori activity.

    CONCLUSION: Dentatin possesses gastro-protective activity, which could be attributed to the anti-secretory, mucus production, anti-oxidant, and HSP70 activities.

    Matched MeSH terms: HSP70 Heat-Shock Proteins/metabolism
  5. Thymoquinone induces apoptosis and increase ROS in ovarian cancer cell line
    Taha MM, Sheikh BY, Salim LZ, Mohan S, Khan A, Kamalidehghan B, et al.
    Cell Mol Biol (Noisy-le-grand), 2016 May 30;62(6):97-101.
    PMID: 27262811
    Nigella sativa is also known for its properties as a traditional herbal healing for many ailments. In this study, the anticancer properties of thyomquinone (TQ), the active ingredient of N. sativa, were studied using ovarian cancer cell line (Caov-3 cells). The anti-proliferative activity of TQ was determined using MTT and the apoptosis was investigated using Flowcytometry and Annexin-V Assays. Multiparameteric cytotoxicity bioassays were used to quantify the changes in cell permeability and mitochondrial membrane potential. Reactive oxygen species (ROS) and apoptosis-involved cell markers were examined to verify cell death mechanism. The MTT-assay showed that TQ induces anti-proliferative activity on Caov-3 with an IC50 of 6.0±0.03 μg/mL, without any cytotoxic activity towards WRL-68 normal hepatocytes. A significant induction of early phase of apoptosis was shown by annexin-V analysis. Treatment of Caov-3 cells with TQ induces decreases in plasma membrane permeability and mitochondrial membrane potential. Visible decrease in the nuclear area was also observed. A significant decrease is observed in Bcl-2 while Bax is down-regulated. TQ-triggered ROS-mediated has found to be associated with Hsp70 dysregulation, an indicator of oxidative injury. We found that TQ induced anti-cancer effect involves intrinsic pathway of apoptosis and cellular oxidative stress. Our results considered collectively indicated that thyomquinone may be a potential agent for ovarian cancer drug development.
    Matched MeSH terms: HSP70 Heat-Shock Proteins/metabolism
  6. The mechanistic role of active site residues in non-stereo haloacid dehalogenase E (DehE)
    Zainal Abidin MH, Abd Halim KB, Huyop F, Tengku Abdul Hamid TH, Abdul Wahab R, Abdul Hamid AA
    J Mol Graph Model, 2019 07;90:219-225.
    PMID: 31103914 DOI: 10.1016/j.jmgm.2019.05.003
    Dehalogenase E (DehE) is a non-stereospecific enzyme produced by the soil bacterium, Rhizobium sp. RC1. Till now, the catalytic mechanism of DehE remains unclear although several literature concerning its structure and function are available. Since DehE is non-stereospecific, the enzyme was hypothesized to follow a 'direct attack mechanism' for the catalytic breakdown of a haloacid. For a molecular insight, the DehE modelled structure was docked in silico with the substrate 2-chloropropionic acid (2CP) in the active site. The ideal position of DehE residues that allowed a direct attack mechanism was then assessed via molecular dynamics (MD) simulation. It was revealed that the essential catalytic water was hydrogen bonded to the 'water-bearer', Asn114, at a relatively constant distance of ∼2.0 Å after 50 ns. The same water molecule was also closely sited to the catalytic Asp189 at an average distance of ∼2.0 Å, signifying the imperative role of the latter to initiate proton abstraction for water activation. This reaction was crucial to promote a direct attack on the α-carbon of 2CP to eject the halide ion. The water molecule was oriented favourably towards the α-carbon of 2CP at an angle of ∼75°, mirrored by the formation of stable enzyme-substrate orientations throughout the simulation. The data therefore substantiated that the degradation of a haloacid by DehE followed a 'direct attack mechanism'. Hence, this study offers valuable information into future advancements in the engineering of haloacid dehalogenases with improved activity and selectivity, as well as functionality in solvents other than water.
    Matched MeSH terms: Bacterial Proteins/metabolism*
  7. Fulltext Cytotoxic Effects and Anti-Angiogenesis Potential of Pistachio (Pistacia vera L.) Hulls against MCF-7 Human Breast Cancer Cells
    Seifaddinipour M, Farghadani R, Namvar F, Mohamad J, Abdul Kadir H
    Molecules, 2018 Jan 05;23(1).
    PMID: 29303970 DOI: 10.3390/molecules23010110
    Pistachio (Pistacia vera L.) hulls (PVLH) represents a significant by-product of industrial pistachio processing that contains high amounta of phenolic and flavonoid compounds known to act as antioxidants. The current study was designed to evaluate the anti-tumor and anti-angiogenic potentials of PVLH extracts. The cytotoxic effects of hexane, ethyl acetate, methanol, and water PVLH extracts toward human colon cancer (HT-29 and HCT-116), breast adenocarcinoma (MCF-7), lung adenocarcinoma (H23), liver hepatocellular carcinoma (HepG2), cervical cancer (Ca Ski), and normal fibroblast (BJ-5ta) cells were assessed using a MTT cell viability assay. Apoptosis induction was evaluated through the different nuclear staining assays and confirmed by flow cytometry analysis. Anti-angiogenic activities were also determined using chorioallantoic membrane (CAM) assay. PVLH ethyl acetate extracts (PVLH-EAE) demonstrated a suppressive effect with an IC50 value of 21.20 ± 1.35, 23.00 ± 1.2 and 25.15 ± 1.85 µg/mL against MCF-7, HT-29 and HCT-116, respectively, after 72 h of treatment. Morphological assessment and flow cytometry analysis showed the potential of PVLH-EAE to induce apoptosis. PVLH-EAE at the highest concentration demonstrated significant inhibition of angiogenesis as comparing with control group. Also the expression of Bax increased and the expression of Bcl-2 decreased in treated MCF-7 cells. Thus, the apoptosis induction and angiogenesis potential of PVLH-EAE make it to be the most suitable for further cancer research study to deal with selective antitumor active substances to human cancers especially breast cancer.
    Matched MeSH terms: Apoptosis Regulatory Proteins/metabolism
  8. Mesua ferrea stem bark extract induces apoptosis and inhibits metastasis in human colorectal carcinoma HCT 116 cells, through modulation of multiple cell signalling pathways
    Asif M, Shafaei A, Abdul Majid AS, Ezzat MO, Dahham SS, Ahamed MBK, et al.
    Chin J Nat Med, 2017 Jul;15(7):505-514.
    PMID: 28807224 DOI: 10.1016/S1875-5364(17)30076-6
    Considering the great potential of natural products as anticancer agents, the present study was designed to explore the molecular mechanisms responsible for anticancer activities of Mesua ferrea stem bark extract against human colorectal carcinoma. Based on MTT assay results, bioactive sub-fraction (SF-3) was selected for further studies using HCT 116 cells. Repeated column chromatography resulted in isolation of less active α-amyrin from SF-3, which was identified and characterized by GC-MS and HPLC methods. α-amyrin and betulinic acid contents of SF-3 were measured by HPLC methods. Fluorescent assays revealed characteristic apoptotic features, including cell shrinkage, nuclear condensation, and marked decrease in mitochondrial membrane potential in SF-3 treated cells. In addition, increased levels of caspases-9 and -3/7 levels were also observed in SF-3 treated cells. SF-3 showed promising antimetastatic properties in multiple in vitro assays. Multi-pathway analysis revealed significant down-regulation of WNT, HIF-1α, and EGFR with simultaneous up-regulation of p53, Myc/Max, and TGF-β signalling pathways in SF-3 treated cells. In addition, promising growth inhibitory effects were observed in SF-3 treated HCT 116 tumour spheroids, which give a hint about in vivo antitumor efficacy of SF-3 phytoconstituents. In conclusion, these results demonstrated that anticancer effects of SF-3 towards colon cancer are through modulation of multiple molecular pathways.
    Matched MeSH terms: Wnt Proteins/metabolism
  9. Fulltext Radioprotective Effects of Kelulut Honey in Zebrafish Model
    Adenan MNH, Yazan LS, Christianus A, Md Hashim NF, Mohd Noor S, Shamsudin S, et al.
    Molecules, 2021 Mar 12;26(6).
    PMID: 33809054 DOI: 10.3390/molecules26061557
    Large doses of ionizing radiation can damage human tissues. Therefore, there is a need to investigate the radiation effects as well as identify effective and non-toxic radioprotectors. This study evaluated the radioprotective effects of Kelulut honey (KH) from stingless bee (Trigona sp.) on zebrafish (Danio rerio) embryos. Viable zebrafish embryos at 24 hpf were dechorionated and divided into four groups, namely untreated and non-irradiated, untreated and irradiated, KH pre-treatment and amifostine pre-treatment. The embryos were first treated with KH (8 mg/mL) or amifostine (4 mM) before irradiation at doses of 11 Gy to 20 Gy using gamma ray source, caesium-137 (137Cs). Lethality and abnormality analysis were performed on all of the embryos in the study. Immunohistochemistry assay was also performed using selected proteins, namely γ-H2AX and caspase-3, to investigate DNA damages and incidences of apoptosis. KH was found to reduce coagulation effects at up to 20 Gy in the lethality analysis. The embryos developed combinations of abnormality, namely microphthalmia (M), body curvature and microphthalmia (BM), body curvature with microphthalmia and microcephaly (BMC), microphthalmia and pericardial oedema (MO), pericardial oedema (O), microphthalmia with microcephaly and pericardial oedema (MCO) and all of the abnormalities (AA). There were more abnormalities developed from 24 to 72 h (h) post-irradiation in all groups. At 96 h post-irradiation, KH was identified to reduce body curvature effect in the irradiated embryos (up to 16 Gy). γ-H2AX and caspase-3 intensities in the embryos pre-treated with KH were also found to be lower than the untreated group at gamma irradiation doses of 11 Gy to 20 Gy and 11 Gy to 19 Gy, respectively. KH was proven to increase the survival rate of zebrafish embryos and exhibited protection against organ-specific abnormality. KH was also found to possess cellular protective mechanism by reducing DNA damage and apoptosis proteins expression.
    Matched MeSH terms: Zebrafish Proteins/metabolism
  10. Fulltext Molecular characterization of a recombinant manganese superoxide dismutase from Lactococcus lactis M4
    Tan BH, Chor Leow T, Foo HL, Abdul Rahim R
    Biomed Res Int, 2014;2014:469298.
    PMID: 24592392 DOI: 10.1155/2014/469298
    A superoxide dismutase (SOD) gene of Lactococcus lactis M4 was cloned and expressed in a prokaryotic system. Sequence analysis revealed an open reading frame of 621 bp which codes for 206 amino acid residues. Expression of sodA under T7 promoter exhibited a specific activity of 4967 U/mg when induced with 1 mM of isopropyl-β-D-thiogalactopyranoside. The recombinant SOD was purified to homogeneity by immobilised metal affinity chromatography and Superose 12 gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot analyses of the recombinant SOD detected a molecular mass of approximately 27 kDa. However, the SOD was in dimer form as revealed by gel filtration chromatography. The purified recombinant enzyme had a pI of 4.5 and exhibited maximal activity at 25°C and pH 7.2. It was stable up to 45°C. The insensitivity of this lactococcal SOD to cyanide and hydrogen peroxide established that it was a MnSOD. Although it has 98% homology to SOD of L. lactis IL1403, this is the first elucidated structure of lactococcal SOD revealing active sites containing the catalytic manganese coordinated by four ligands (H-27, H-82, D-168, and H-172).
    Matched MeSH terms: Recombinant Proteins/metabolism*
  11. Fulltext Effects of lysine and methionine in a low crude protein diet on the growth performance and gene expression of immunity genes in broilers
    Lee CY, Song AA, Loh TC, Abdul Rahim R
    Poult Sci, 2020 Jun;99(6):2916-2925.
    PMID: 32475425 DOI: 10.1016/j.psj.2020.03.013
    Globally, the poultry industry is 1 of the most advanced livestock industries. Feed contributes to the biggest proportion (65-70%) of the production cost. Most feed ingredients in Malaysia are imported, which contributes to the high food bill annually, and alternative feed formulation may help decrease the cost of poultry feed. Feed formulation are improved to efficiently meet the dietary requirements of the broilers and 1 of the ways is by reducing the level of crude protein in the diet while supplementing essential amino acids. In this study, the effects of methionine and lysine, which are the 2 most limiting amino acids in the chicken diet, were supplemented in a low crude protein diet, and its effects on the growth and expression of immunity genes such as MUC2, SLC, GAL6, and LEAP-2 were studied. A total of 300 Cobb500 broilers were tested with 10 different dietary treatments. Experimental treatment diets consist of high, standard, and low levels of methionine and lysine in the diet with reduced crude protein. The control group consists of diet with standard levels of lysine, methionine, and crude protein as recommended for Cobb500 broilers. Ribonucleic acid was extracted from the jejunum, spleen, and liver for gene expression analysis which was performed with real-time polymerase chain reaction using SYBR Green chemistry. Results of the growth performance at 6 wk showed improved feed conversion ratio when lysine was increased by 0.2% in a low crude protein diet at 1.96 ± 0.11. Gene expression of MUC2 gene in the jejunum showed a significant increase across all experimental diets with the treatment with higher lysine in low crude protein diet with the highest increase of 3.8 times as compared with the control diet. The other genes expressed in the spleen and liver were mostly downregulated. It was concluded that supplementation of high lysine with standard methionine in a low crude protein diet performed better in terms of lowest feed conversion ratio and high upregulation of MUC2 gene.
    Matched MeSH terms: Avian Proteins/metabolism
  12. Secretion of recombinant xylanase in Lactococcus lactis using signal peptides Usp45 and Spk1
    Roslan AM, Mustafa Kamil A, Chandran C, Song AA, Yusoff K, Abdul Rahim R
    Biotechnol Lett, 2020 Sep;42(9):1727-1733.
    PMID: 32335791 DOI: 10.1007/s10529-020-02894-1
    OBJECTIVE: The effect of two signal peptides, namely Usp45 and Spk1 on the secretion of xylanase in Lactococcus lactis was analysed.

    RESULTS: Xylanase was successfully expressed in Lactococcus lactis. Recombinant xylanase fused to either signal peptide Usp45 or Spk1 showed halo zone on Remazol Brilliant Blue-Xylan plates. This indicated that the xylanase was successfully secreted from the cell. The culture supernatants of strains secreting the xylanase with help of the Spk1 and Usp45 signal peptides contained 49.7 U/ml and 34.4 U/ml of xylanase activity, respectively.

    CONCLUSION: Although Usp45 is the most commonly used signal peptide when secreting heterologous proteins in Lactococcus lactis, this study shows that Spk1 isolated from Pediococcus pentosaceus was superior to Usp45 in regard to xylanase protein secretion.

    Matched MeSH terms: Recombinant Fusion Proteins/metabolism*
  13. Bioinformatics survey of the metal usage by psychrophilic yeast Glaciozyma antarctica PI12
    Foong PM, Abedi Karjiban R, Normi YM, Salleh AB, Abdul Rahman MB
    Metallomics, 2015 Jan;7(1):156-64.
    PMID: 25412156 DOI: 10.1039/c4mt00163j
    Metal ions are one of the essential elements which are extensively involved in many cellular activities. With rapid advancements in genome sequencing techniques, bioinformatics approaches have provided a promising way to extract functional information of a protein directly from its primary structure. Recent findings have suggested that the metal content of an organism can be predicted from its complete genome sequences. Characterizing the biological metal usage of cold-adapted organisms may help to outline a comprehensive understanding of the metal-partnerships between the psychrophile and its adjacent environment. The focus of this study is targeted towards the analysis of the metal composition of a psychrophilic yeast Glaciozyma antarctica PI12 isolated from sea ice of Antarctica. Since the cellular metal content of an organism is usually reflected in the expressed metal-binding proteins, the putative metal-binding sequences from G. antarctica PI12 were identified with respect to their sequence homologies, domain compositions, protein families and cellular distribution. Most of the analyses revealed that the proteome was enriched with zinc, and the content of metal decreased in the order of Zn > Fe > Mg > Mn, Ca > Cu. Upon comparison, it was found that the metal compositions among yeasts were almost identical. These observations suggested that G. antarctica PI12 could have inherited a conserved trend of metal usage similar to modern eukaryotes, despite its geographically isolated habitat.
    Matched MeSH terms: Carrier Proteins/metabolism; Fungal Proteins/metabolism
  14. Molecular dynamics of thermoenzymes at high temperature and pressure: a review
    Abedi Karjiban R, Lim WZ, Basri M, Abdul Rahman MB
    Protein J, 2014 Aug;33(4):369-76.
    PMID: 24871480 DOI: 10.1007/s10930-014-9568-8
    Lipases are known for their versatility in addition to their ability to digest fat. They can be used for the formulation of detergents, as food ingredients and as biocatalysts in many industrial processes. Because conventional enzymes are frangible at high temperatures, the replacement of conventional chemical routes with biochemical processes that utilize thermostable lipases is vital in the industrial setting. Recent theoretical studies on enzymes have provided numerous fundamental insights into the structures, folding mechanisms and stabilities of these proteins. The studies corroborate the experimental results and provide additional information regarding the structures that were determined experimentally. In this paper, we review the computational studies that have described how temperature affects the structure and dynamics of thermoenzymes, including the thermoalkalophilic L1 lipase derived from Bacillus stearothermophilus. We will also discuss the potential of using pressure for the analysis of the stability of thermoenzymes because high pressure is also important for the processing and preservation of foods.
    Matched MeSH terms: Bacterial Proteins/metabolism
  15. Fulltext Molecular Cloning, Characterization, and Application of Organic Solvent-Stable and Detergent-Compatible Thermostable Alkaline Protease from Geobacillus thermoglucosidasius SKF4
    Allison SD, AdeelaYasid N, Shariff FM, Abdul Rahman N
    J Microbiol Biotechnol, 2024 Feb 28;34(2):436-456.
    PMID: 38044750 DOI: 10.4014/jmb.2306.06050
    Several thermostable proteases have been identified, yet only a handful have undergone the processes of cloning, comprehensive characterization, and full exploitation in various industrial applications. Our primary aim in this study was to clone a thermostable alkaline protease from a thermophilic bacterium and assess its potential for use in various industries. The research involved the amplification of the SpSKF4 protease gene, a thermostable alkaline serine protease obtained from the Geobacillus thermoglucosidasius SKF4 bacterium through polymerase chain reaction (PCR). The purified recombinant SpSKF4 protease was characterized, followed by evaluation of its possible industrial applications. The analysis of the gene sequence revealed an open reading frame (ORF) consisting of 1,206 bp, coding for a protein containing 401 amino acids. The cloned gene was expressed in Escherichia coli. The molecular weight of the enzyme was measured at 28 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The partially purified enzyme has its highest activity at a pH of 10 and a temperature of 80°C. In addition, the enzyme showed a half-life of 15 h at 80°C, and there was a 60% increase in its activity at 10 mM Ca2+ concentration. The activity of the protease was completely inhibited (100%) by phenylmethylsulfonyl fluoride (PMSF); however, the addition of sodium dodecyl sulfate (SDS) resulted in a 20% increase in activity. The enzyme was also stable in various organic solvents and in certain commercial detergents. Furthermore, the enzyme exhibited strong potential for industrial use, particularly as a detergent additive and for facilitating the recovery of silver from X-ray film.
    Matched MeSH terms: Bacterial Proteins/metabolism
  16. A facile enzymatic synthesis of geranyl propionate by physically adsorbed Candida rugosa lipase onto multi-walled carbon nanotubes
    Mohamad NR, Buang NA, Mahat NA, Lok YY, Huyop F, Aboul-Enein HY, et al.
    Enzyme Microb Technol, 2015 May;72:49-55.
    PMID: 25837507 DOI: 10.1016/j.enzmictec.2015.02.007
    In view of several disadvantages as well as adverse effects associated with the use of chemical processes for producing esters, alternative techniques such as the utilization of enzymes on multi-walled carbon nanotubes (MWCNTs), have been suggested. In this study, the oxidative MWCNTs prepared using a mixture of HNO3 and H2SO4 (1:3 v/v) were used as a supportive material for the immobilization of Candida rugosa lipase (CRL) through physical adsorption process. The resulting CRL-MWCNTs biocatalysts were utilized for synthesizing geranyl propionate, an important ester for flavoring agent as well as in fragrances. Enzymatic esterification of geraniol with propionic acid was carried out using heptane as a solvent and the efficiency of CRL-MWCNTs as a biocatalyst was compared with the free CRL, considering the incubation time, temperature, molar ratio of acid:alcohol, presence of desiccant as well as its reusability. It was found that the CRL-MWCNTs resulted in a 2-fold improvement in the percentage of conversion of geranyl propionate when compared with the free CRL, demonstrating the highest yield of geranyl propionate at 6h at 55°C, molar ratio acid: alcohol of 1:5 and with the presence of 1.0g desiccant. It was evident that the CRL-MWCNTs biocatalyst could be reused for up to 6 times before a 50% reduction in catalytic efficiency was observed. Hence, it appears that the facile physical adsorption of CRL onto F-MWCNTs has improved the activity and stability of CRL as well as served as an alternative method for the synthesis of geranyl propionate.
    Matched MeSH terms: Fungal Proteins/metabolism*
  17. Melatonin improves cognitive behavior, oxidative stress, and metabolism in tumor-prone lethal giant larvae mutant of Drosophila melanogaster
    Wong KC, Sankaran S, Jayapalan JJ, Subramanian P, Abdul-Rahman PS
    Arch Insect Biochem Physiol, 2021 May;107(1):e21785.
    PMID: 33818826 DOI: 10.1002/arch.21785
    Mutant lethal giant larvae (lgl) flies (Drosophila melanogaster) are known to develop epithelial tumors with invasive characteristics. The present study has been conducted to investigate the influence of melatonin (0.025 mM) on behavioral responses of lgl mutant flies as well as on biochemical indices (redox homeostasis, carbohydrate and lipid metabolism, transaminases, and minerals) in hemolymph, and head and intestinal tissues. Behavioral abnormalities were quantitatively observed in lgl flies but were found normalized among melatonin-treated lgl flies. Significantly decreased levels of lipid peroxidation products and antioxidants involved in redox homeostasis were observed in hemolymph and tissues of lgl flies, but had restored close to normalcy in melatonin-treated flies. Carbohydrates including glucose, trehalose, and glycogen were decreased and increased in the hemolymph and tissues of lgl and melatonin-treated lgl flies, respectively. Key enzymes of carbohydrate metabolism showed a significant increment in their levels in lgl mutants but had restored close to wild-type baseline levels in melatonin-treated flies. Variables of lipid metabolism showed significantly inverse levels in hemolymph and tissues of lgl flies, while normalization of most of these variables was observed in melatonin-treated mutants. Lipase, chitinase, transaminases, and alkaline phosphatase showed an increment in their activities and minerals exhibited decrement in lgl flies; reversal of changes was observed under melatonin treatment. The impairment of cognition, disturbance of redox homeostasis and metabolic reprogramming in lgl flies, and restoration of normalcy in all these cellular and behavioral processes indicate that melatonin could act as oncostatic and cytoprotective agents in Drosophila.
    Matched MeSH terms: Drosophila Proteins/metabolism
  18. Potential serum biomarkers associated with mild and severe leptospirosis infection: A cohort study in the Malaysian population
    Tan XT, Amran FB, Thayan R, Ahmad N, Jaafar R, Haron R, et al.
    Electrophoresis, 2017 09;38(17):2141-2149.
    PMID: 28524240 DOI: 10.1002/elps.201600471
    Leptospirosis is an emerging zoonotic infectious disease in Malaysia. The symptoms of leptospirosis vary from mild nonspecific flu-like illness to a severe condition which is usually associated with serious complication and fatality. To study the protein expression profile of mild and severe leptospirosis, 15 paired sera were collected from the patients who were mildly infected and following that progressed to severe stage. The proteome profiles of mild and severe cases were studied using 2DE analysis in combination with LC-MS/MS. The expression of proteins that were significantly different and had a fold difference of at least 2 had been identified and then validated using Western blot. Our study demonstrated apolipoprotein A-I (APOA-I), serum amyloid A (SAA), transferrin (TF), haptoglobin (HP) and transthyretin (TTR) have significantly different expression between mild and severe leptospirosis. The Ingenuity Pathway Analysis software suggested the expression of these five proteins were modulated by acute phase response signaling pathway. Besides that, a functional network of lipid metabolism, molecular transport and small molecule biochemistry that interconnects these five proteins with interactomes also had been predicted by this software. In conclusion, this finding supports the potential of these five proteins to be the biomarkers for mild and severe human leptospirosis.
    Matched MeSH terms: Acute-Phase Proteins/metabolism
  19. Fulltext Biochanin a gastroprotective effects in ethanol-induced gastric mucosal ulceration in rats
    Hajrezaie M, Salehen N, Karimian H, Zahedifard M, Shams K, Al Batran R, et al.
    PLoS One, 2015;10(3):e0121529.
    PMID: 25811625 DOI: 10.1371/journal.pone.0121529
    BACKGROUND: Biochanin A notable bioactive compound which is found in so many traditional medicinal plant. In vivo study was conducted to assess the protective effect of biochanin A on the gastric wall of Spraguedawley rats` stomachs.

    METHODOLOGY: The experimental set included different animal groups. Specifically, four groups with gastric mucosal lesions were receiving either a) Ulcer control group treated with absolute ethanol (5 ml/kg), b) 20 mg/kg of omeprazole as reference group, c) 25 of biochanin A, d) 50 mg/kg of biochanin A. Histopathological sectioning followed by immunohistochemistry staining were undertaken to evaluate the influence of the different treatments on gastric wall mucosal layer. The gastric secretions were collected in the form of homogenate and exposed to superoxide dismutase (SOD) and nitric oxide enzyme (NO) and the level of malondialdehyde (MDA) and protein content were measured. Ulceration and patchy haemorrhage were clearly observed by light microscopy. The morphology of the gastric wall as confirmed by immunohistochemistry and fluorescent microscopic observations, exhibited sever deformity with notable thickness, oedematous and complete loss of the mucosal coverage however the biochanin-pretreated animals, similar to the omeprazole-pretreated animals, showed less damage compared to the ulcer control group. Moreover, up-regulation of Hsp70 protein and down-regulation of Bax protein were detected in the biochanin A pre-treated groups and the gastric glandular mucosa was positively stained with Periodic Acid Schiff (PAS) staining and the Leucocytes infiltration was commonly seen. Biochanin A displayed a great increase in SOD and NO levels and decreased the release of MDA.

    CONCLUSIONS: This gastroprotective effect of biochanin A could be attributed to the enhancement of cellular metabolic cycles perceived as an increase in the SOD, NO activity, and decrease in the level of MDA, and also decrease in level of Bax expression and increase the Hsp70 expression level.

    Matched MeSH terms: HSP70 Heat-Shock Proteins/metabolism
  20. Fulltext In vivo antioxidant and antiulcer activity of Parkia speciosa ethanolic leaf extract against ethanol-induced gastric ulcer in rats
    Al Batran R, Al-Bayaty F, Jamil Al-Obaidi MM, Abdualkader AM, Hadi HA, Ali HM, et al.
    PLoS One, 2013;8(5):e64751.
    PMID: 23724090 DOI: 10.1371/journal.pone.0064751
    BACKGROUND: The current study was carried out to examine the gastroprotective effects of Parkia speciosa against ethanol-induced gastric mucosa injury in rats.

    METHODOLOGY/PRINCIPAL FINDINGS: Sprague Dawley rats were separated into 7 groups. Groups 1-2 were orally challenged with carboxymethylcellulose (CMC); group 3 received 20 mg/kg omeprazole and groups 4-7 received 50, 100, 200 and 400 mg/kg of ethanolic leaf extract, respectively. After 1 h, CMC or absolute ethanol was given orally to groups 2-7. The rats were sacrificed after 1 h. Then, the injuries to the gastric mucosa were estimated through assessment of the gastric wall mucus, the gross appearance of ulcer areas, histology, immunohistochemistry and enzymatic assays. Group 2 exhibited significant mucosal injuries, with reduced gastric wall mucus and severe damage to the gastric mucosa, whereas reductions in mucosal injury were observed for groups 4-7. Groups 3-7 demonstrated a reversal in the decrease in Periodic acid-Schiff (PAS) staining induced by ethanol. No symptoms of toxicity or death were observed during the acute toxicity tests.

    CONCLUSION: Treatment with the extract led to the upregulation of heat-shock protein 70 (HSP70) and the downregulation of the pro-apoptotic protein BAX. Significant increases in the levels of the antioxidant defense enzymes glutathione (GSH) and superoxide dismutase (SOD) in the gastric mucosal homogenate were observed, whereas that of a lipid peroxidation marker (MDA) was significantly decreased. Significance was defined as p<0.05 compared to the ulcer control group (Group 2).

    Matched MeSH terms: HSP70 Heat-Shock Proteins/metabolism
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