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  1. γ-Tocotrienol prevents cell cycle arrest in aged human fibroblast cells through p16INK4a pathway
    Zainuddin A, Chua KH, Tan JK, Jaafar F, Makpol S
    J Physiol Biochem, 2017 Feb;73(1):59-65.
    PMID: 27743340 DOI: 10.1007/s13105-016-0524-2
    Human diploid fibroblasts (HDFs) proliferation in culture has been used as a model of aging at the cellular level. Growth arrest is one of the most important mechanisms responsible for replicative senescence. Recent researches have been focusing on the function of vitamin E in modulating cellular signaling and gene expression. Therefore, the aim of this study was to elucidate the effect of palm γ-tocotrienol (vitamin E) in modulating cellular aging through p16INK4a pathway in HDF cells. Primary culture of senescent HDFs was incubated with 70 μM of palm γ-tocotrienol for 24 hours. Silencing of p16INK4a was carried out by siRNA transfection. RNA was extracted from the different treatment groups and gene expression analysis was carried out by real-time reverse transcription polymerase chain reaction. Proteins that were regulated by p16INK4a were determined by western blot technique. The finding of this study showed that p16INK4a mRNA was overexpressed in senescent HDFs, and hypophosphorylated-pRb and cyclin D1 protein expressions were increased (p 
    Matched MeSH terms: Fibroblasts/enzymology
  2. Fulltext γ-Secretase Inhibitors and Modulators Induce Distinct Conformational Changes in the Active Sites of γ-Secretase and Signal Peptide Peptidase
    Gertsik N, Chau DM, Li YM
    ACS Chem. Biol., 2015 Aug 21;10(8):1925-31.
    PMID: 26030233 DOI: 10.1021/acschembio.5b00321
    γ-Secretase inhibitors (GSIs) and modulators (GSMs) are at the frontline of cancer and Alzheimer's disease research, respectively. While both are therapeutically promising, not much is known about their interactions with proteins other than γ-secretase. Signal peptide peptidase (SPP), like γ-secretase, is a multispan transmembrane aspartyl protease that catalyzes regulated intramembrane proteolysis. We used active site-directed photophore walking probes to study the effects of different GSIs and GSMs on the active sites of γ-secretase and SPP and found that nontransition state GSIs inhibit labeling of γ-secretase by activity-based probes but enhance labeling of SPP. The opposite is true of GSMs, which have little effect on the labeling of γ-secretase but diminish labeling of SPP. These results demonstrate that GSIs and GSMs are altering the structure of not only γ-secretase but also SPP, leading to potential changes in enzyme activity and specificity that may impact the clinical outcomes of these molecules.
    Matched MeSH terms: Alzheimer Disease/enzymology
  3. miR-608 regulates apoptosis in human lung adenocarcinoma via regulation of AKT2
    Othman N, Nagoor NH
    Int J Oncol, 2017 Dec;51(6):1757-1764.
    PMID: 29075783 DOI: 10.3892/ijo.2017.4174
    Lung cancer remains a major health problem with a low 5-year survival rate of patients. Recent studies have shown that dysregulation of microRNAs (miRNAs) are prevalent in lung cancer and these aberrations play a significant role in the progression of tumour progression. In the present study, bioinformatics analyses was employed to predict potential miR-608 targets, which are associated with signaling pathways involved in cancer. Luciferase reporter assay identified AKT2 as a novel target of miR-608, and suppression of its protein levels was validated through western blot analysis. Zebrafish embryos were microinjected with cells transfected with miR-608 to elucidate the role of miR-608 in vivo, and immunostained with antibodies to detect activated caspase-3. We present the first evidence that miR-608 behaves as a tumour suppressor in A549 and SK-LU-1 cells through the regulation of AKT2, suggesting that selective targeting of AKT2 via miR-608 may be developed as a potential therapeutic strategy for miRNA-based non-small cell lung cancer (NSCLC) therapy.
    Matched MeSH terms: Adenocarcinoma/enzymology*; Lung Neoplasms/enzymology*
  4. d-galactose and aluminium chloride induced rat model with cognitive impairments
    Chiroma SM, Mohd Moklas MA, Mat Taib CN, Baharuldin MTH, Amon Z
    Biomed Pharmacother, 2018 Jul;103:1602-1608.
    PMID: 29864948 DOI: 10.1016/j.biopha.2018.04.152
    Cognitive impairments and cholinergic dysfunctions have been well reported in old age disorders including Alzheimer's disease (AD). d-galactose (D-gal) has been reported as a senescence agent while aluminium act as a neurotoxic metal, but little is known about their combined effects at different doses. The aim of this study was to establish an animal model with cognitive impairments by comparing the effects of different doses of co-administrated D-gal and aluminium chloride (AlCl3). In this study male albino wistar rats were administered with D-gal 60 mg/kg.bwt intra peritoneally (I.P) injected and AlCl3 (100, 200, or 300 mg/kg.bwt.) was orally administered once daily for 10 consecutive weeks. Performance of the rats were evaluated through behavioural assessments; Morris water maze (MWM) and open field tests (OFT); histopathological examination was performed on the hippocampus; moreover biochemical measurements of acetylcholinesterase (AChE) and hyperphosphorylated tau protein (p-tau) were examined. The results of this experiment on rats treated with D-gal 60 + AlCl3 200 mg/kg.bwt showed near ideal cognitive impairments. The rats exhibited an obvious memory and learning deficits, marked neuronal loss in hippocampus, showed increase in AChE activities and high expression of p-tau within the tissues of the brain. This study concludes that D-gal 60 + AlCl3 200 mg/kg.bwt as the ideal dose for mimicking AD like cognitive impairments in albino wistar rats. It is also crucial to understand the pathogenesis of this neurodegenerative disease and for drug discovery.
    Matched MeSH terms: Hippocampus/enzymology
  5. beta-Lactam resistance phenotype determination in Escherichia coli isolates from University Malaya Medical Centre
    Wong JS, Mohd Azri ZA, Subramaniam G, Ho SE, Palasubramaniam S, Navaratnam P
    Malays J Pathol, 2003 Dec;25(2):113-9.
    PMID: 16196367
    beta-Lactamases have been identified as the major cause of antimicrobial resistance to beta-lactam antibiotics in Escherichia coli. The activities of ampicillin-sulbactam and amoxicillin-clavulanate as well as a range of beta-lactam antibiotics were studied with 87 clinical E. coli isolates from patients of the University Malaya Medical Center using the disc diffusion technique. Susceptible, intermediate and resistant categories were established based on the diameter of zones of inhibition set by the National Committee for Clinical Laboratory Standards (NCCLS). The isolates were then classified into 6 phenotypes according to the criteria stated in the methodology: S (susceptible to all beta-lactams); TL (resistant to aminopenicillins; amoxicillin-clavulanate susceptible and susceptible or intermediate to ampicillin-sulbactam); TI (resistant to aminopenicillins and ampicillin-sulbactam; susceptible to amoxicilin-clavulanate); TH-IRT (resistant to aminopenicillins; intermediate or resistant to amoxicillin-clavulanate; resistant to ampicillin-sulbactam); ESBL (resistant to aminopenicillins and oxyimino cephalosporins; positive results with the double-disc diffusion test); and CP (resistant to aminopenicillins, beta-lactam-beta-lactamase inhibitor combinations, oxyimino cephalosporins and cephamycins). Results showed that the TL phenotype was the commonest (40.2% of the isolates) followed by S (31%), TH-IRT (16.1%), ESBL and CP (3.4% each) and TI (2.3%). One isolate showed both ESBL and CP phenotypes while two isolates were classified as inconclusive. Representatives from each phenotype were further analysed for the presence of beta-lactamases which revealed a predominance of TEM and SHV enzyme producers. PCR-SSCP analysis of the SHV gene from all the ESBL and CP isolates revealed the predominance of SHV 5-type enzyme which was concurrent with our previous studies.
    Matched MeSH terms: Escherichia coli/enzymology
  6. beta-Galactosidase and its significance in ripening mango fruit
    Ali ZM, Armugam S, Lazan H
    Phytochemistry, 1995 Mar;38(5):1109-14.
    PMID: 7766393
    The fruit extracts of ripening cv. Harumanis mango contained a number of glycosidases and glycanases. Among the glycosidases, beta-D-galactosidase (EC 3.2.1.23) appeared to be the most significant. The enzyme activity increased in parallel with increase in tissue softness during ripening. Mango beta-galactosidase was fractionated into three isoforms, viz. beta-galactosidase I, II and III by a combination of chromatographic procedures on DEAE-Sepharose CL-6B, CM-Sepharose and Sephacryl S-200 columns. Apparent Km values for the respective beta-galactosidase isoforms for p-nitrophenyl beta-D-galactoside were 3.7, 3.3 and 2.7 mM, and their Vmax values were 209, 1024 and 62 nkat mg-1 protein. Optimum activity occurred at ca pH 3.2 for beta-galactosidase I and II, and pH 3.6 for beta-galactosidase III. Mango beta-galactosidase and its isoforms have galactanase activity, and the activity of the latter in the crude extracts generally increased during ripening. The close correlation between changes in beta-galactosidase activity, tissue softness, and increased pectin solubility and degradation suggests that beta-galactosidase might play an important role in cell wall pectin modification and softening of mango fruit during ripening.
    Matched MeSH terms: Fruit/enzymology*
  7. alpha-Tocopherol increased nitric oxide synthase activity in blood vessels of spontaneously hypertensive rats
    Newaz MA, Nawal NN, Rohaizan CH, Muslim N, Gapor A
    Am J Hypertens, 1999 Aug;12(8 Pt 1):839-44.
    PMID: 10480480
    Antioxidant protection provided by different doses of alpha-tocopherol was compared by determining nitric oxide synthase (NOS) activity in blood vessels of spontaneously hypertensive rats (SHR) treated with alpha-tocopherol. SHR were divided into four groups namely hypertensive control (C), treatment with 17 mg of alpha-tocopherol/kg diet (alpha1), 34 mg of alpha-tocopherol/kg diet (alpha2), and 170 mg of alpha-tocopherol/kg diet (alpha3). Wister Kyoto (WKY) rats were used as normal control (N). Blood pressure were recorded from the tail by physiography every other night for the duration of the study period of 3 months. At the end of the trial, animals were sacrificed. The NOS activity in blood vessels was measured by [3H]arginine radioactive assay and the nitrite concentration in plasma by spectrophotometry at wavelength 554 nm using Greiss reagent. Analysis of data was done using Student's t test and Pearson's correlation. The computer program Statistica was used for all analysis. Results of our study showed that for all the three alpha-tocopherol-treated groups, blood pressure was significantly (P < .001) reduced compared to the hypertensive control and maximum reduction of blood pressure was shown by the dosage of 34 mg of alpha-tocopherol/kg diet (C: 209.56 +/- 8.47 mm Hg; alpha2: 128.83 +/- 17.13 mm Hg). Also, NOS activity in blood vessels of SHR was significantly lower than WKY rats (N: 1.54 +/- 0.26 pmol/mg protein, C: 0.87 +/- 0.23 pmol/mg protein; P < .001). Although alpha-tocopherol in doses of alpha1, alpha2, and alpha3 increased the NOS activity in blood vessels, after treatment only that of alpha2 showed a statistical significance (P < .01). Plasma nitrite concentration was significantly reduced in SHR compared to normal WKY rats (N: 54.62 +/- 2.96 mol/mL, C: 26.24 +/- 2.14 mol/mL; P < .001) and accordingly all three groups showed significant improvement in their respective nitrite level (P < .001). For all groups, NOS activity and nitrite level showed negative correlation with blood pressure. It was significant for NOS activity in hypertensive control (r = -0.735, P = .038), alpha1 (r = -0.833, P = .001), and alpha2 (r = -0.899, P = .000) groups. For plasma nitrite, significant correlation was observed only in group alpha1 (r = -0.673, P = .016) and alpha2 (r = -0.643, P = .024). Only the alpha2 group showed significant positive correlation (r = 0.777, P = .003) between NOS activity and nitrite level. In conclusion it was found that compared to WKY rats, SHR have lower NOS activity in blood vessels, which upon treatment with antioxidant alpha-tocopherol increased the NOS activity and concomitantly reduced the blood pressure. There was correlation of lipid peroxide in blood vessels with NOS and nitric oxide, which implies that free radicals may be involved in the pathogenesis of hypertension.
    Matched MeSH terms: Blood Vessels/enzymology*; Hypertension/enzymology*
  8. Xylanase production by Aspergillus niger FTCC 5003 using palm kernel cake in fermentative bioprocess
    Abdeshahian P, Samat N, Yusoff WM
    Pak J Biol Sci, 2009 Aug 01;12(15):1049-55.
    PMID: 19943460
    The production of xylanase from palm kernel cake as a substrate was studied in solid substrate fermentation. The simultaneous effects of three independent variables, namely incubation temperature, initial moisture content of substrate and air flow rate on xylanase production were evaluated by response surface methodology using central composite face centered design. A total of 18 experiments were carried out in which Aspergillus niger FTCC 5003 was cultivated on palm kernel cake in a column bioreactor for 7 days under incubation temperature, moisture level and aeration rate determined. Test results showed that the highest xylanase activity of 174.88 U g(-1) was produced at incubation temperature, initial moisture level and aeration rate of 25 degrees C, 60% and 1.5 L min(-1), respectively. The statistical analysis of the experimental results revealed that the linear effect of incubation temperature and quadratic term of initial moisture content had highly significant effects on xylanase production (p<0.01). Statistical results also showed that interaction effect between incubation temperature and initial moisture content as well as interaction effect between moisture level and aeration rate influenced the yield ofxylanase at probability levels of 95%. Optimum conditions determined by statistical model for attaining maximum xylanase production were incubation temperature of 25 degrees C, initial moisture level of 63% and aeration rate of 1.76 L min(-1). The xylanase activity of 192.50 U g(-1) was obtained when solid substrate fermentation was performed under the optimal circumstances.
    Matched MeSH terms: Aspergillus niger/enzymology*
  9. Xanthenone-based hydrazones as potent α-glucosidase inhibitors: Synthesis, solid state self-assembly and in silico studies
    Tariq QU, Malik S, Khan A, Naseer MM, Khan SU, Ashraf A, et al.
    Bioorg Chem, 2019 03;84:372-383.
    PMID: 30530108 DOI: 10.1016/j.bioorg.2018.11.053
    Xanthenone based hydrazone derivatives (5a-n) have been synthesized as potential α-glucosidase inhibitors. All synthesized compounds (5a-n) are characterized by their FTIR, 1H NMR, 13C NMR and HRMS, and in case of 5g also by X-ray crystallographic technique. The compounds unveiled a varying degree of α-glucosidase inhibitory activity when compared with standard acarbose (IC50 = 375.38 ± 0.12 µM). Amongst the series, compound 5l (IC50 = 62.25 ± 0.11 µM) bearing a trifluoromethyl phenyl group is found to be the most active compound. Molecular modelling is performed to establish the binding pattern of the more active compound 5l, which revealed the significance of substitution pattern. The pharmacological properties of molecules are also calculated by MedChem Designer which determines the ADME (absorption, distribution, metabolism, excretion) properties of molecules. The solid state self-assembly of compound 5g is discussed to show the conformation and role of iminoamide moiety in the molecular packing.
    Matched MeSH terms: Saccharomyces cerevisiae/enzymology
  10. Fulltext X-linked chronic granulomatous disease in a male child with an X-CGD carrier, Klinefelter brother
    Gill HK, Kumar HC, Cheng CK, Ming CC, Nallusamy R, Yusoff NM, et al.
    Asian Pac J Allergy Immunol, 2013 Jun;31(2):167-72.
    PMID: 23859418 DOI: 10.12932/AP0274.31.2.2013
    BACKGROUND: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency (PID) caused by a dysfunctional respiratory burst enzyme NADPH-oxidase. The concurrence of Klinefelter’s Syndrome (KS) and CGD would be extremely rare.
    OBJECTIVE: We describe the study of a family where the youngest male child had X-linked CGD (X-CGD) while his older brother was both an X-CGD carrier and a Klinefelter.
    METHODS: Flow cytometry was used to study respiratory burst and gp91-phox expression, while genetic investigation was done by RT-PCR, PCR and X-chromosome short tandem repeat (X-STR) analysis.
    RESULTS: The Dihydrorhodamine (DHR) assay showed the patient’s neutrophils failed to produce a respiratory burst, while both the mother and an older brother showed a bimodal response. gp91-phox expression was absent in the patient’s neutrophils, and bimodal in the mother’s and brother’s neutrophils. The patient’s cDNA showed a C>T change at nucleotide 676 of the CYBB gene. The same change was seen in the patient’s gDNA, while the brother and mother were heterozygous, with C and T, in this position. The c.676C>T is a nonsense mutation that leads to premature termination of the gp91-phox protein. The brother karyotyped as 47, XXY and X chromosome analysis showed that he had inherited both his mother’s X chromosomes.
    CONCLUSIONS: This study showed that the patient had gp91-phox deficient CGD while his older brother was a CGD carrier and a Klinefelter, who had inherited both his mother’s X chromosomes. This is the first report of such a concurrence in an individual, and argues for family members to be included in PID studies.
    Key words: Chronic granulomatous disease, CYBB, gp91-phox, Klinefelter’s syndrome NADPHoxidase
    Matched MeSH terms: Granulomatous Disease, Chronic/enzymology; Klinefelter Syndrome/enzymology; Genetic Diseases, X-Linked/enzymology
  11. Fulltext Wound healing activity of Elaeis guineensis leaf extract ointment
    Sasidharan S, Logeswaran S, Latha LY
    Int J Mol Sci, 2012;13(1):336-47.
    PMID: 22312255 DOI: 10.3390/ijms13010336
    Elaeis guineensis of the Arecaceae family is widely used in the traditional medicine of societies in West Africa for treating various ailments. To validate the ethnotherapeutic claims of the plant in skin diseases, wound healing activity was studied. The results showed that E. guineensis leaf extract had potent wound healing capacity as evident from the better wound closure (P < 0.05), improved tissue regeneration at the wound site, and supporting histopathological parameters pertaining to wound healing. Matrix metalloproteinases expression correlated well with the results thus confirming efficacy of E. guineensis in the treatment of the wound. E. guineensis accelerated wound healing in rats, thus supporting its traditional use. The result of this study suggested that, used efficiently, oil palm leaf extract is a renewable resource with wound healing properties.
    Matched MeSH terms: Skin/enzymology
  12. Fulltext Why hypothetical protein KPN00728 of Klebsiella pneumoniae should be classified as chain C of succinate dehydrogenase?
    Choi SB, Normi YM, Wahab HA
    Protein J, 2009 Dec;28(9-10):415-27.
    PMID: 19859792 DOI: 10.1007/s10930-009-9209-9
    Twenty percent of genes that encode for hypothetical proteins from Klebsiella pneumoniae MGH78578 were identified, leading to KPN00728 and KPN00729 after bioinformatics analysis. Both open reading frames showed high sequence homology to Succinate dehydrogenase Chain C (SdhC) and D (SdhD) from Escherichia coli. Recently, KPN00729 was assigned as SdhD. KPN00728 thus remains of particular interest as no annotated genes from the complete genome sequence encode for SdhC. We discovered KPN00728 has a missing region with conserved residues important for ubiquinone (UQ) and heme group binding. Structure and function prediction of KPN00728 coupled with secondary structure analysis and transmembrane topology showed KPN00728 adopts SDH-(subunit C)-like structure. To further probe its functionality, UQ was docked on the built model (consisting KPN00728 and KPN00729) and formation of hydrogen bonds between UQ and Ser27, Arg31 (KPN00728) and Tyr84 (KPN00729) further reinforces and supports that KPN00728 is indeed SDH. This is the first report on the structural and function prediction of KPN00728 of K. pneumoniae MGH78578 as SdhC.
    Matched MeSH terms: Klebsiella pneumoniae/enzymology*
  13. Whole genome strategies and bioremediation insight into dehalogenase-producing bacteria
    Oyewusi HA, Wahab RA, Huyop F
    Mol Biol Rep, 2021 Mar;48(3):2687-2701.
    PMID: 33650078 DOI: 10.1007/s11033-021-06239-7
    An integral approach to decoding both culturable and uncultured microorganisms' metabolic activity involves the whole genome sequencing (WGS) of individual/complex microbial communities. WGS of culturable microbes, amplicon sequencing, metagenomics, and single-cell genome analysis are selective techniques integrating genetic information and biochemical mechanisms. These approaches transform microbial biotechnology into a quick and high-throughput culture-independent evaluation and exploit pollutant-degrading microbes. They are windows into enzyme regulatory bioremediation pathways (i.e., dehalogenase) and the complete bioremediation process of organohalide pollutants. While the genome sequencing technique is gaining the scientific community's interest, it is still in its infancy in the field of pollutant bioremediation. The techniques are becoming increasingly helpful in unraveling and predicting the enzyme structure and explore metabolic and biodegradation capabilities.
    Matched MeSH terms: Bacteria/enzymology*
  14. Water activity effect on lipase immobilized onto different compositions of poly(HEMA-MMA)
    Esa NM, Yunus WM, Ahmad MB, Basri M, Razak CN, Salleh AB
    Ann N Y Acad Sci, 1998 Dec 13;864:489-92.
    PMID: 9928130
    Matched MeSH terms: Candida/enzymology
  15. Vitamin D deficiency attenuates endothelial function by reducing antioxidant activity and vascular eNOS expression in the rat microcirculation
    Wee CL, Mokhtar SS, Banga Singh KK, Rasool AHG
    Microvasc Res, 2021 Nov;138:104227.
    PMID: 34324883 DOI: 10.1016/j.mvr.2021.104227
    This study examined the effects of vitamin D deficiency on vascular function and tissue oxidative status in the microcirculation; and whether or not these effects can be ameliorated with calcitriol, the active vitamin D metabolite. Three groups (n = 10 each) of male Sprague Dawley rats were fed for 10 weeks with control diet (CR), vitamin D-deficient diet without (DR), or with oral calcitriol supplementation (0.15 μg/kg) for the last four weeks (DSR). After 10 weeks, rats were sacrificed; mesenteric arterial rings were studied using wire myograph. Oxidative stress biomarkers malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured in the mesenteric arterial tissue. Vascular protein expression of endothelial nitric oxide synthase (eNOS) was determined by Western blotting. Acetylcholine-induced endothelium-dependent relaxation of DR was lower than CR. eNOS expression and SOD activity were lower in mesenteric arterial tissue of DR compared to CR. Calcitriol supplementation to DSR did not ameliorate the above parameters; in fact, augmented endothelium-dependent contraction was observed. Serum calcium was higher in DSR compared to CR and DR. In conclusion, vitamin D deficiency impaired microvascular vasodilation, associated with eNOS downregulation and reduced antioxidant activity. Calcitriol supplementation to vitamin D-deficient rats at the dosage used augmented endothelium-dependent contraction, possibly due to hypercalcaemia.
    Matched MeSH terms: Endothelium, Vascular/enzymology*; Vitamin D Deficiency/enzymology*; Microvessels/enzymology*
  16. Fulltext Vernonia amygdalina simultaneously suppresses gluconeogenesis and potentiates glucose oxidation via the pentose phosphate pathway in streptozotocin-induced diabetic rats
    Atangwho IJ, Yin KB, Umar MI, Ahmad M, Asmawi MZ
    BMC Complement Altern Med, 2014;14:426.
    PMID: 25358757 DOI: 10.1186/1472-6882-14-426
    This study evaluated the impact of Vernonia amygdalina (VA) on the transcription of key enzymes involved in cellular modulation of glucose in streptozotocin-induced diabetic rats in a bid to understand the possible anti-diabetic mechanism of VA.
    Matched MeSH terms: Diabetes Mellitus, Experimental/enzymology*; Liver/enzymology
  17. Venomics of Calloselasma rhodostoma, the Malayan pit viper: A complex toxin arsenal unraveled
    Tang EL, Tan CH, Fung SY, Tan NH
    J Proteomics, 2016 10 04;148:44-56.
    PMID: 27418434 DOI: 10.1016/j.jprot.2016.07.006
    The venom of Malayan pit viper (Calloselasma rhodostoma) is highly toxic but also valuable in drug discovery. However, a comprehensive proteome of the venom that details its toxin composition and abundance is lacking. This study aimed to unravel the venom complexity through a multi-step venomic approach. At least 96 distinct proteins (29 basic, 67 acidic) in 11 families were identified from the venom. The venom consists of mainly snake venom metalloproteinases (SVMP, 41.17% of total venom proteins), within which the P-I (kistomin, 20.4%) and P-II (rhodostoxin, 19.8%) classes predominate. This is followed by C-type lectins (snaclec, 26.3%), snake venom serine protease (SVSP, 14.9%), L-amino acid oxidase (7.0%), phospholipase A2 (4.4%), cysteine-rich secretory protein (2.5%), and five minor toxins (nerve growth factor, neurotrophin, phospholipase B, 5' nucleotidase and phosphodiesterase, totaling 2.6%) not reported in the proteome hitherto. Importantly, all principal hemotoxins unveiled correlate with the syndrome: SVSP ancrod causes venom-induced consumptive coagulopathy, aggravated by thrombocytopenia caused by snaclec rhodocytin, a platelet aggregation inducer, while P-II rhodostoxin mediates hemorrhage, exacerbated by P-I kistomin and snaclec rhodocetin that inhibit platelet plug formation. These toxins exist in multiple isoforms and/or complex subunits, deserving further characterization for the development of an effective, polyspecific regional antivenom.

    BIOLOGICAL SIGNIFICANCE: Advents in proteomics and bioinformatics have vigorously propelled the scientific discoveries of toxins from various lineages of venomous snakes. The Malayan pit viper, Calloselasma rhodostoma, is a medically important species in Southeast Asia as its bite can cause envenomation, while the venom is also a source of bioactive compounds for drug discovery. Detailed profiling of the venom, however, is inadequate possibly due to the complex nature of the venom and technical limitation in separating the constituents into details. Integrating a multi-step fractionation method, this study successfully revealed a comprehensive and quantitative profile of the composition of the venom of this medically important venomous snake. The relative abundance of the various venom proteins is determined in a global profile, providing useful information for understanding the pathogenic roles of the different toxins in C. rhodostoma envenomation. Notably, the principal hemotoxins were identified in great details, including the variety of toxin subunits and isoforms. The findings indicate that these toxins are the principal targets for effective antivenom neutralization, and should be addressed in the production of a pan-regional polyspecific antivenom. In addition, minor toxin components not reported previously in the venom were also detected in this study, enriching the current toxin database for the venomous snakes.

    Matched MeSH terms: Viper Venoms/enzymology
  18. Variation of several erythrocyte enzymes in the Dayaks of Sarawak
    Ganesan J, Lie-Injo LE, Ong Beng P
    Hum. Hered., 1976;26(2):124-7.
    PMID: 181317
    The Land and Sea Dayaks of Sarawak were surveyed for several erythrocyte enzymes. The gene frequency of 6PGDC in 132 Land Dayaks and 127 Sea Dayaks were 0.045 and 0.047, respectively. The gene frequency of PGM1-1 IN 285 Land Dayks and 240 Sea Dayaks were 0.716 and 0.779, respectively. The ADA2 gene frequency in 283 Land Dayaks and 188 Sea Dayaks were 0.154 and 0.090. ADA 5-1 was found once in the Land Dayaks and once in the Sea Dayaks. AK 2-1 was found once in 221 Sea Dayaks but not in any of 270 Land Dayaks. No PHI, LDH or CA variants were found among the Land or Sea Dayaks.
    Matched MeSH terms: Erythrocytes/enzymology*
  19. Utilization of palm kernel cake for production of beta-mannanase by Aspergillus niger FTCC 5003 in solid substrate fermentation using an aerated column bioreactor
    Abdeshahian P, Samat N, Hamid AA, Yusoff WM
    J Ind Microbiol Biotechnol, 2010 Jan;37(1):103-9.
    PMID: 19937085 DOI: 10.1007/s10295-009-0658-0
    The production of beta-mannanase from palm kernel cake (PKC) as a substrate in solid substrate fermentation (SSF) was studied using a laboratory column bioreactor. The simultaneous effects of three independent variables, namely incubation temperature, initial moisture content of substrate and airflow rate, on beta-mannanase production were evaluated by response surface methodology (RSM) on the basis of a central composite face-centered (CCF) design. Eighteen trials were conducted in which Aspergillus niger FTCC 5003 was cultivated on PKC in an aerated column bioreactor for seven days under SSF process. The highest level of beta-mannanase (2117.89 U/g) was obtained when SSF process was performed at incubation temperature, initial moisture level and aeration rate of 32.5 degrees C, 60% and 0.5 l/min, respectively. Statistical analysis revealed that the quadratic terms of incubation temperature and initial moisture content had significant effects on the production of beta-mannanase (P < 0.01). A similar analysis also demonstrated that the linear effect of initial moisture level and an interaction effect between the initial moisture content and aeration rate significantly influenced the production of beta-mannanase (P < 0.01). The statistical model suggested that the optimal conditions for attaining the highest level of beta-mannanase were incubation temperature of 32 degrees C, initial moisture level of 59% and aeration rate of 0.5 l/min. A beta-mannanase yield of 2231.26 U/g was obtained when SSF process was carried out under the optimal conditions described above.
    Matched MeSH terms: Aspergillus niger/enzymology*
  20. Use of response surface methodology for partitioning, one-step purification of alkaline extracellular lipase from Penicillium candidum (PCA 1/TT031)
    Alhelli AM, Abdul Manap MY, Mohammed AS, Mirhosseini H, Suliman E, Shad Z, et al.
    J Chromatogr B Analyt Technol Biomed Life Sci, 2016 Dec 15;1039:66-73.
    PMID: 27836491 DOI: 10.1016/j.jchromb.2016.10.037
    This report shows the partitioning and purification of alkaline extracellular lipase from Penicillium candidum (PCA 1/TT031) by solid-state fermentation (SSF). In the present analysis, some of the important parameters such as PEG concentration, PEG molecular mass, salt concentration and buffer concentration were optimised through the response surface methodology (RSM). The optimum aqueous two-phase systems (ATPS) environment consisted of 13.8% (w/w) phosphate buffer, 9.2% (w/w) PEG-3000 and 3.3% (w/w) NaCl at 25°C. The RSM approach was proved to be the most suitable methodology for the recovery of desired enzymes. In this method, the enzyme partitioned into the top phase of the PEG-buffer-NaCl ATPS. Under this experimental environment, the purification factor was found to be 33.9, the partition coefficient was 4.0 and the yield was found to be 84.0% of lipase. Moreover, the experimental and predicted results were in considerable agreement, which established the reliability and validity of the proposed model. The ATPS methodology is proven to be effective for the primary recovery of lipase at a low cost with a large loading capacity and possibility of linear scale up. In addition to using the existing methodologies for improving enzyme production, the use of statistical optimisation of the constituents of phases through RSM continues to be the basic and practical method.
    Matched MeSH terms: Penicillium/enzymology*
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