Displaying publications 81 - 100 of 223 in total

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  1. Fulltext Discovery of a new class of inhibitors for the protein arginine deiminase type 4 (PAD4) by structure-based virtual screening
    Teo CY, Shave S, Chor AL, Salleh AB, Rahman MB, Walkinshaw MD, et al.
    BMC Bioinformatics, 2012;13 Suppl 17:S4.
    PMID: 23282142 DOI: 10.1186/1471-2105-13-S17-S4
    BACKGROUND: Rheumatoid arthritis (RA) is an autoimmune disease with unknown etiology. Anticitrullinated protein autoantibody has been documented as a highly specific autoantibody associated with RA. Protein arginine deiminase type 4 (PAD4) is the enzyme responsible for catalyzing the conversion of peptidylarginine into peptidylcitrulline. PAD4 is a new therapeutic target for RA treatment. In order to search for inhibitors of PAD4, structure-based virtual screening was performed using LIDAEUS (Ligand discovery at Edinburgh university). Potential inhibitors were screened experimentally by inhibition assays.

    RESULTS: Twenty two of the top-ranked water-soluble compounds were selected for inhibitory screening against PAD4. Three compounds showed significant inhibition of PAD4 and their IC50 values were investigated. The structures of the three compounds show no resemblance with previously discovered PAD4 inhibitors, nor with existing drugs for RA treatment.

    CONCLUSION: Three compounds were discovered as potential inhibitors of PAD4 by virtual screening. The compounds are commercially available and can be used as scaffolds to design more potent inhibitors against PAD4.

    Matched MeSH terms: Hydrolases/antagonists & inhibitors*; Hydrolases/biosynthesis; Hydrolases/chemistry
  2. Interactions of non-natural halogenated substrates with D-specific dehalogenase (DehD) mutants using in silico studies
    Sudi IY, Shamsir MS, Jamaluddin H, Wahab RA, Huyop F
    Biotechnology, biotechnological equipment, 2014 Sep 03;28(5):949-957.
    PMID: 26019583
    The D-2-haloacid dehalogenase of D-specific dehalogenase (DehD) from Rhizobium sp. RC1 catalyses the hydrolytic dehalogenation of D-haloalkanoic acids, inverting the substrate-product configuration and thereby forming the corresponding L-hydroxyalkanoic acids. Our investigations were focused on DehD mutants: R134A and Y135A. We examined the possible interactions between these mutants with haloalkanoic acids and characterized the key catalytic residues in the wild-type dehalogenase, to design dehalogenase enzyme(s) with improved potential for dehalogenation of a wider range of substrates. Three natural substrates of wild-type DehD, specifically, monochloroacetate, monobromoacetate and D,L-2,3-dichloropropionate, and eight other non-natural haloalkanoic acids substrates of DehD, namely, L-2-chloropropionate; L-2-bromopropionate; 2,2-dichloropropionate; dichloroacetate; dibromoacetate; trichloroacetate; tribromoacetate; and 3-chloropropionate, were docked into the active site of the DehD mutants R134A and Y135A, which produced altered catalytic functions. The mutants interacted strongly with substrates that wild-type DehD does not interact with or degrade. The interaction was particularly enhanced with 3-chloropropionate, in addition to monobromoacetate, monochloroacetate and D,L-2,3-dichloropropionate. In summary, DehD variants R134A and Y135A demonstrated increased propensity for binding haloalkanoic acid and were non-stereospecific towards halogenated substrates. The improved characteristics in these mutants suggest that their functionality could be further exploited and harnessed in bioremediations and biotechnological applications.
    Matched MeSH terms: Hydrolases
  3. Fulltext Genome Sequence of Anoxybacillus thermarum AF/04T, Isolated from the Euganean Hot Springs in Abano Terme, Italy
    Poli A, Nicolaus B, Chan KG, Kahar UM, Chan CS, Goh KM
    Genome Announc, 2015;3(3).
    PMID: 25999577 DOI: 10.1128/genomeA.00490-15
    Anoxybacillus thermarum AF/04(T) was isolated from the Euganean hot springs in Abano Terme, Italy. The present work reports a high-quality draft genome sequence of strain AF/04(T). This work also provides useful insights into glycoside hydrolases, glycoside transferases, and sugar transporters that may be involved in cellular carbohydrate metabolism.
    Matched MeSH terms: Glycoside Hydrolases
  4. A comparative study of the enzymatic and toxic properties of venoms of the Asian lance-headed pit viper (Genus Trimeresurus)
    Tan NH, Armugam A, Tan CS
    Comp. Biochem. Physiol., B, 1989;93(4):757-62.
    PMID: 2553329
    1. The lethalities, anticoagulant effects, hermorrhagic, thrombin-like enzyme, hyaluronidase, protease, arginine ester hydrolase, 5'-nucleotidase, L-amino acid oxidase, alkaline phosphomonoesterase, phosphodiesterase and phospholipase A activities of twenty-three samples of venoms from twelve species of Asian lance-headed pit vipers (genus Trimeresurus) were examined. 2. The results indicate that notwithstanding individual variations in venom properties, the differences in biological properties of the Trimeresurus venoms can be used for the differentiation of venoms from different species of Trimeresurus. 3. The results also suggest that differences in the biological properties of snake venoms are useful parameters in the classification of snake species. 4. Our results indicate that venoms from the species T. okinavensis exhibited biological properties markedly different from other Trimeresurus venoms examined. This observation supports the recently proposed reclassification of T. okinavensis as a member of the genus Ovophis, rather than the genus Trimeresurus.
    Matched MeSH terms: Carboxylic Ester Hydrolases/metabolism; Phosphoric Diester Hydrolases/metabolism
  5. Characterization and utilization of pulp and paper mill sludge digesting thermophilic bacteria in composting process
    Le Van Thien, Ngo Thi Tuong Chau, Pham Thi Ngoc Lan, Hiroyuki Futamata
    Sains Malaysiana, 2018;47:1051-1060.
    Pulp and paper mill sludge (PPMS) was found to be poorly colonised with thermophilic microorganisms. However,
    evidence to support the need for inoculation to facilitate PPMS composting has only been demonstrated in one instance.
    In this study, we aimed to: screen and identify PPMS digesting thermophilic bacterial strains; investigate effects of the
    mixture of selected thermophilic bacterial strains on PPMS digestion; and utilize this mixture as start inoculum in PPMS
    composting and assess the quality of compost product. The results showed that eleven thermophilic bacterial strains were
    isolated from Bai Bang PPMS by the enrichment culture method. Among these, three strains which reflected high growth
    rates on the plates of Minimal Media Agar supplemented with Bai Bang PPMS and showed hydrolytic and ligninolytic
    activities on the agar plates containing appropriate inductive substrates were selected. Based on the morphological,
    biochemical characteristics and 16S rRNA gene sequencing, they were identified as Bacillus subtilis. The inoculation
    with the mixture of selected strains enhanced remarkably Bai Bang PPMS digestion. The dry weight decrease, volatile
    suspended solids removal, dehydrogenase and protease activities in the inoculated sludge were 2.1-, 1.5-, 1.3- and 1.2-
    fold higher, respectively, compared to the non-inoculated sludge. The assessment of compost quality based on stability
    using the alkaline trap method and maturity using the germination and root elongation test showed that the inoculated
    compost was stable and mature while the non-inoculated compost was unstable and immature. These thermophilic
    bacterial strains therefore have great potential for Bai Bang PPMS composting.
    Matched MeSH terms: Peptide Hydrolases
  6. Catalysis by Glomerella cingulata cutinase requires conformational cycling between the active and inactive states of its catalytic triad
    Nyon MP, Rice DW, Berrisford JM, Hounslow AM, Moir AJ, Huang H, et al.
    J Mol Biol, 2009 Jan 9;385(1):226-35.
    PMID: 18983850 DOI: 10.1016/j.jmb.2008.10.050
    Cutinase belongs to a group of enzymes that catalyze the hydrolysis of esters and triglycerides. Structural studies on the enzyme from Fusarium solani have revealed the presence of a classic catalytic triad that has been implicated in the enzyme's mechanism. We have solved the crystal structure of Glomerella cingulata cutinase in the absence and in the presence of the inhibitors E600 (diethyl p-nitrophenyl phosphate) and PETFP (3-phenethylthio-1,1,1-trifluoropropan-2-one) to resolutions between 2.6 and 1.9 A. Analysis of these structures reveals that the catalytic triad (Ser136, Asp191, and His204) adopts an unusual configuration with the putative essential histidine His204 swung out of the active site into a position where it is unable to participate in catalysis, with the imidazole ring 11 A away from its expected position. Solution-state NMR experiments are consistent with the disrupted configuration of the triad observed crystallographically. H204N, a site-directed mutant, was shown to be catalytically inactive, confirming the importance of this residue in the enzyme mechanism. These findings suggest that, during its catalytic cycle, cutinase undergoes a significant conformational rearrangement converting the loop bearing the histidine from an inactive conformation, in which the histidine of the triad is solvent exposed, to an active conformation, in which the triad assumes a classic configuration.
    Matched MeSH terms: Carboxylic Ester Hydrolases/antagonists & inhibitors; Carboxylic Ester Hydrolases/metabolism*; Carboxylic Ester Hydrolases/chemistry*
  7. Expression of the serum opacity factor gene and the variation in its upstream region in Streptococcus dysgalactiae isolates from fish
    Nishiki I, Minami T, Chen SC, Itami T, Yoshida T
    J Gen Appl Microbiol, 2012;58(6):457-63.
    PMID: 23337581
    Group C Streptococcus dysgalactiae (GCSD) is a pathogen of farmed fish. Almost all GCSD isolates from Asian countries, including Japan, Taiwan, Malaysia, and China, have a serum opacity factor (SOF-FD). Although the SOF-FD sequences in different GCSD isolates are identical, different opacification activities are observed. Three types of variations were observed in the upstream sequence of the sof-FD gene in GCSD isolates with different SOF-FD activities. Type 1 was characterized by insertion of an IS981-like element into the upstream region of the sof-FD gene. In Type 2, an IS981-like element was inserted into the upstream region in a direction opposite to that in Type 1. In Type 3, no IS element was inserted. Type 1 was predominant among Japanese isolates (129 of 133). Isolates from other Asian countries were generally Type 3 (13 of 16). Except for 1 strain, Type 1 strains exhibited opacification activities with optical densities (ODs)>0.6, while Type 2 and Type 3 strains have low opacification activities (ODs >0.2). Only Type 1 strains have putative -10 and -35 promoter regions upstream of the sof-FD gene, and the expression level of the sof-FD gene was higher in Type 1 strains than in Type 2 and Type 3 strains.
    Matched MeSH terms: Peptide Hydrolases/genetics; Peptide Hydrolases/metabolism*; Peptide Hydrolases/chemistry
  8. High level expression of Glomerella cingulata cutinase in dense cultures of Pichia pastoris grown under fed-batch conditions
    Seman WM, Bakar SA, Bukhari NA, Gaspar SM, Othman R, Nathan S, et al.
    J Biotechnol, 2014 Aug 20;184:219-28.
    PMID: 24910973 DOI: 10.1016/j.jbiotec.2014.05.034
    A Pichia pastoris transformant carrying the cutinase cDNA of Glomerella cingulata was over-expressed in a 5L bioreactor (2.0L working volume) under fed-batch conditions. Bioreactor experiments rely on varying selected parameters in repeated rounds of optimisation: here these included duration of induction, pH and temperature. Highest cell densities (320gL(-1) wet cell weight) with a cutinase production of 3800mgL(-1) and an activity of 434UmL(-1) were achieved 24h after induction with methanol in basal salt medium (at pH 5 and 28°C). Characterisation of the cutinase showed that it was stable between pH 6 and pH 11, had an optimum pH of 8.0 and retained activity for 30min at 50°C (optimum temperature 25°C).The preferred substrates of G. cingulata cutinase were the medium- to long-chain ρ-nitrophenyl esters of ρ-nitrophenylcaprylate (C8), ρ-nitrophenyllaurate (C12) and ρ-nitrophenylmyristate (C14), with the highest catalytic efficiency, kcat/Km of 7.7±0.7mM(-1)s(-1) for ρ-nitrophenylcaprylate. Microscopic analyses showed that the G. cingulata cutinase was also capable of depolymerising the high molecular weight synthetic polyester, polyethylene terephthalate.
    Matched MeSH terms: Carboxylic Ester Hydrolases/biosynthesis*; Carboxylic Ester Hydrolases/metabolism; Carboxylic Ester Hydrolases/chemistry
  9. Phosphodiesterase as a Target for Cognition Enhancement in Schizophrenia
    Al-Nema MY, Gaurav A
    Curr Top Med Chem, 2020;20(26):2404-2421.
    PMID: 32533817 DOI: 10.2174/1568026620666200613202641
    Schizophrenia is a severe mental disorder that affects more than 1% of the population worldwide. Dopamine system dysfunction and alterations in glutamatergic neurotransmission are strongly implicated in the aetiology of schizophrenia. To date, antipsychotic drugs are the only available treatment for the symptoms of schizophrenia. These medications, which act as D2-receptor antagonist, adequately address the positive symptoms of the disease, but they fail to improve the negative symptoms and cognitive impairment. In schizophrenia, cognitive impairment is a core feature of the disorder. Therefore, the treatment of cognitive impairment and the other symptoms related to schizophrenia remains a significant unmet medical need. Currently, phosphodiesterases (PDEs) are considered the best drug target for the treatment of schizophrenia since many PDE subfamilies are abundant in the brain regions that are relevant to cognition. Thus, this review aims to illustrate the mechanism of PDEs in treating the symptoms of schizophrenia and summarises the encouraging results of PDE inhibitors as anti-schizophrenic drugs in preclinical and clinical studies.
    Matched MeSH terms: Phosphoric Diester Hydrolases
  10. Fulltext Biochemical Properties and Potential Application of Proteases from Alkalophilic Bacillus lehensis G1
    Nur Zazarina Ramly, Nor Muhammad Mahadi, Noorul Aini Sulaiman
    Trop Life Sci Res, 2019;30(2):1-14.
    MyJurnal
    Pencirian enzim ekstraselular protease daripada bakteria Alkalophilic Bacillus lehensis G1 dari Malaysia telah dikaji. Enzim protease yang dirembeskan diuji pada agar susu skim 2%. Keputusan menunjukkan protease ekstraselular mampu mengekalkan aktiviti sehingga suhu 60°C di dalam julat pH yang luas iaitu 3 hingga 11 dengan suhu optimum pada 40°C dan pH optimum pada 7.0. Aktiviti enzim juga diperhatikan akan meningkat dengan penambahan beberapa ion iaitu Mn2+, Fe2+, Cu2+, Mg2+ dan Co2+. Manakala aktiviti protease didapati sedikit direncat dengan kehadiran ion Ca2+, K+ dan Ni2+ dengan baki aktiviti sebanyak 85%, 81% dan 75%. Protease ekstraselular juga didapati serasi dengan beberapa cecair detergen komersial dari Malaysia, yang menunjukkan protease ini boleh dimanfaatkan sebagai pembersih kotoran pada pakaian. Selain itu, potensi kegunaan protease yang dihasilkan oleh B. lehensis G1 ke atas penguraian gelatin dari filem X-ray yang telah digunakan juga telah dilakukan di dalam kajian ini.
    Matched MeSH terms: Peptide Hydrolases
  11. Fulltext Enzymatic preparation of palm kernel expeller protein hydrolysate (PKEPH)
    Ng, K.L., Mohd Khan, A.
    International Food Research Journal, 2012;19(2):721-725.
    MyJurnal
    Utilization of palm kernel expeller (PKE), a palm oil milling by-product, may be diversified through the exploitation of its protein component. The PKE protein could be effectively extracted using an alkaline
    solution and followed by enzymatic hydrolysis to produce PKE protein hydrolysates or crude PKE peptide. The extraction of PKE protein was successfully carried out using an alkaline solution at pH11, at ratio of 1:10 (g/ml), PKE powder to alkaline solution with continuous shaking, 150 rpm, in a water bath operating at 50°C for 30 min. The extracted protein powder (PKEP) had 68.50±3.08% crude protein, 0.54±0.03% fat and 0.73±0.02% ash. The freeze-dried PKEP was re-suspend in particular buffer and hydrolyzed with proteolytic enzymes (Alcalase® 2.4L, Flavourzyme® 500MG, pepsin or trypsin) to obtain PKEP hydrolysate (PKEPH). The effect of enzyme concentration (0, 2, 4, 6, 8 & 10%) and time of hydrolysis (0, 6, 12, 24, 48 h) was studied to determine the most efficient hydrolytic conditions. Results showed that all enzymes tested were capable of hydrolyzing the PKEP and producing hydrolysates with different degree of hydrolysis (DH%). At 8.0% concentration, Alcalase®2.4L hydrolyzed PKEP into the highest DH (75.96%) hydrolysate (PKEPH) after 1h hydrolysis. Although only with 2.0% Alcalase 2.4 L concentration, it was sufficient to produce PKEP hydrolysate of 81.35% DH %, but it required 12 h to hydrolyze the protein. Pepsin was relatively the least efficient protease to hydrolyze the PKEP.
    Matched MeSH terms: Peptide Hydrolases
  12. Fulltext Degree of hydrolysis and free tryptophan content of Skipjack Tuna (Katsuwonus pelamis) protein hydrolysates produced with different type of industrial proteases
    Herpandi, Huda, N., Rosma, A., Wan Nadiah W. A.
    International Food Research Journal, 2012;19(3):863-867.
    MyJurnal
    Protein-rich by-products from the canning industry, especially dark flesh of skipjack, have limited uses due to several factors such as darken color, susceptibility to oxidation and off flavour. Protein hydrolysates from skipjack dark flesh was produced with different type of industrial proteases (Alcalase®2.4L FG, Protamex®, Neutrase®1.5MG and Flavourzyme®500MG) for 60, 120, 180 and 240 min with level of proteases used of 0.5, 1, 1.5 and 2% per weight of raw material. The degree of hydrolysis and free tryptophan content of hydrolysate were investigated. The results shows longer time with higher concentration of enzyme has increased the degree of hydrolysis. Alcalase®2.4L FG had the highest degree of hydrolysis among all proteases followed by Protamex®, Flavourzyme®500MG and Neutrase® 1.5MG. All enzymes increase free tryptophan content linearly with the increament of protease enzyme level. The longer the hydrolysis time, the higher the content of free tryptophan produced.
    Matched MeSH terms: Peptide Hydrolases
  13. Fulltext Rapid ecotoxicological tests using bioassay systems - a review
    Halmi, M.I.E.
    Journal of Biochemistry, Microbiology and Biotechnology, 2016;4(1):29-37.
    MyJurnal
    The rise in pollution cases globally is expected to increase in line with industrialization.
    Monitoring activities for pollutants have been hampered by the astronomical costs of
    instrumental-based approach. This has resulted in the intense research on low cost
    biomonitoring systems using enzymes, organisms including microorganisms. Only positive
    samples are sent for instrumental analysis; dramatically cutting the cost of instrumental
    analysis. This review attempts to outline and give due recognition to several selected bioassay
    systems that have been tested for their applicability using polluted water samples as a routine
    first line-of-defense. This includes small aquatic organisms-based assays, enzymes especially
    proteases and bacterial-based systems using respiratory dye or luminescence systems as a
    method for toxicant detection.
    Matched MeSH terms: Peptide Hydrolases
  14. Fulltext Near real-time biomonitoring of copper from an industrial complex effluent discharge site using a plant protease inhibitive assay
    Halmi, M.I.E., Khayat, M.E., Rahman, M.F.A., Gunasekaran, B., Masdor, N.A.
    Bioremediation Science and Technology Research, 2016;4(1):10-13.
    MyJurnal
    In this work, a temporal monitoring work for heavy metals from an effluent discharge point in
    the Juru Industrial Estate was carried out using the protease extracted from garlic (Allium
    sativum) as the principal bioassay system. casein-Coomassie-dye binding assay method has
    utilized this purpose. The periodic sampling results for one day of a location in the Juru
    Industrial Estate showed temporal variation of copper concentration coinciding with garlic
    protease inhibition with the highest concentrations of copper occurring between 12.00 and 16.00
    hours of between 3 and 3.5 mg/L copper. The crude proteases extracted from Allium sativum
    successfully detect temporal variation of copper form this location. In conclusion, this assay
    method has the potential to be a rapid, sensitive, and economic inhibitive assay for the largescale
    biomonitoring works for the heavy metal copper from this area.
    Matched MeSH terms: Peptide Hydrolases
  15. Pengenalpastian dan pencirian gen trichoderma virens ukm1 mengekod enzim terlibat dalam pencuraian kitin krustasea
    Abdul Munir Abdul Murad, Rafidah Badrun, Sakina Shahabudin, Shazilah Kamaruddin, Madihah Ahmad Zairun, Farahayu Khairuddin, et al.
    Sains Malaysiana, 2013;42:715-724.
    Kitin merupakan polisakarida struktur yang dapat dicurai oleh enzim kitinolisis kepada pelbagai terbitan yang boleh digunakan dalam bidang perubatan, pertanian dan rawatan air. Pengenalpastian dan pencirian gen-gen Trichoderma virens UKM1 mengekod enzim terlibat dalam pencuraian kitin krustasea telah dilakukan melalui penjanaan penanda jujukan terekspres (ESTs) dan analisis pengekspresan gen menggunakan mikroatur DNA. Sebanyak tiga perpustakaan cDNA T. virens UKM1 yang masing-masing diaruh oleh kitin, glukosamina dan kitosan telah dibina. Sejumlah 1536 klon cDNA telah dijujuk dan sebanyak 1033 ESTs berkualiti telah dijana. Seterusnya, perbezaan pengekspresan gen apabila pertumbuhan kulat diaruh dengan kehadiran kitin krustasea dan tanpa kitin pada hari ketiga dan kelima telah ditentukan. Sebanyak 1824 klon cDNA telah dititik ke atas slaid kaca dan dihibrid bersama dengan cDNA terlabel Cy3 atau Cy5 yang disintesis daripada mRNA yang dipencil daripada kulat yang ditumbuhkan dalam medium mengandungi kitin krustasea atau glukosa (kawalan). Sebanyak 91 dan 61 gen, masing-masing bagi hari ketiga dan kelima didapati terekspres melebihi dua gandaan apabila kulat menggunakan kitin krustasea sebagai sumber karbon. Beberapa gen mengekod kitinase seperti ech1 dan cht3 (endokitinase), nag1 (eksokitinase) dan nagB (glukosamina 6-P-deaminase) didapati terekspres dengan tinggi pada kedua-dua hari. Selain daripada itu, gen mengekod protein hidrofobin, protease serina dan beberapa protein hipotetik juga terekspres dengan tinggi dengan kehadiran kitin krustasea. Protein-protein ini dijangka memainkan peranan penting dalam membantu pencuraian kitin krustasea.
    Matched MeSH terms: Peptide Hydrolases
  16. In-Silico Characterization of Glycosyl Hydrolase Family 1 β-Glucosidase from Trichoderma asperellum UPM1
    Mohamad Sobri MF, Abd-Aziz S, Abu Bakar FD, Ramli N
    Int J Mol Sci, 2020 Jun 04;21(11).
    PMID: 32512945 DOI: 10.3390/ijms21114035
    β-glucosidases (Bgl) are widely utilized for releasing non-reducing terminal glucosyl residues. Nevertheless, feedback inhibition by glucose end product has limited its application. A noticeable exception has been found for β-glucosidases of the glycoside hydrolase (GH) family 1, which exhibit tolerance and even stimulation by glucose. In this study, using local isolate Trichoderma asperellum UPM1, the gene encoding β-glucosidase from GH family 1, hereafter designated as TaBgl2, was isolated and characterized via in-silico analyses. A comparison of enzyme activity was subsequently made by heterologous expression in Escherichia coli BL21(DE3). The presence of N-terminal signature, cis-peptide bonds, conserved active site motifs, non-proline cis peptide bonds, substrate binding, and a lone conserved stabilizing tryptophan (W) residue confirms the identity of Trichoderma sp. GH family 1 β-glucosidase isolated. Glucose tolerance was suggested by the presence of 14 of 22 known consensus residues, along with corresponding residues L167 and P172, crucial in the retention of the active site's narrow cavity. Retention of 40% of relative hydrolytic activity on ρ-nitrophenyl-β-D-glucopyranoside (ρNPG) in a concentration of 0.2 M glucose was comparable to that of GH family 1 β-glucosidase (Cel1A) from Trichoderma reesei. This research thus underlines the potential in the prediction of enzymatic function, and of industrial importance, glucose tolerance of family 1 β-glucosidases following relevant in-silico analyses.
    Matched MeSH terms: Hydrolases
  17. Fulltext The Efficacy of Traditional Medicinal Plants in Modulating the Main Protease of SARS-CoV-2 and Cytokine Storm
    Choe J, Har Yong P, Xiang Ng Z
    Chem Biodivers, 2022 Nov;19(11):e202200655.
    PMID: 36125969 DOI: 10.1002/cbdv.202200655
    Selected traditional medicinal plants exhibit therapeutic effects in coronavirus disease (Covid-19) patients. This review aims to identify the phytochemicals from five traditional medicinal plants (Glycyrrhiza glabra, Nigella sativa, Curcuma longa, Tinospora cordifolia and Withania somnifera) with high potential in modulating the main protease (Mpro) activity and cytokine storm in Covid-19 infection. The Mpro binding affinity of 13 plant phytochemicals were in the following order: Withanoside II>withanoside IV>withaferin A>α-hederin>withanoside V>sitoindoside IX>glabridin>liquiritigenin, nigellidine>curcumin>glycyrrhizin>tinocordiside>berberine. Among these phytochemicals, glycyrrhizin, withaferin A, curcumin, nigellidine and cordifolioside A suppressed SARS-CoV-2 replication and showed stronger anti-inflammatory activities than standard Covid-19 drugs. Both preclinical and clinical evidences supported the development of plant bioactive compounds as Mpro inhibitors.
    Matched MeSH terms: Peptide Hydrolases
  18. Fulltext Application of membrane-based technology for purification of bromelain
    Nor, M. Z. M., Ramchandran, L., Duke, M., Vasiljevic, T.
    International Food Research Journal, 2017;24(4):1685-1696.
    MyJurnal
    About 60% of world’s commercial enzyme products are proteases, giving promising opportunity
    to derive such enzymes sustainably from waste sources. Bromelain is a crude protease occurring
    naturally in pineapple, and it possesses properties of benefit for pharmaceutical, medical and food products. The production of bromelain involves a purification stage, normally performed by small-scale conventional operations which lead to high operating cost and low product recovery, while being difficult to scale up and produce polluting by-products. Membrane-based technology offers an alternative to produce high quality purified bromelain in a more efficient and sustainable process. This review identified the current state and future needs for utilising membrane processes for sustainable bromelain production at larger scales. It was found that declining membrane flux due to fouling have been reported, but may be effectively overcome with more appropriate (and advanced) membrane types and/or processing conditions. For example, interactions between macromolecules present in the pineapple derived bromelain mixture (particularly polysaccharides) and the membrane may cause performance limiting fouling, but can be overcome by enzymatic pre-treatment. Membrane fouling can be further reduced by the employment of ceramic membrane filters operating at optimised trans-membrane pressure, cross-flow velocity, feed pH and temperature. Two-stage ultrafiltration together with diafiltration or gas sparging was suggested as a means to reduce fouling and improve enzyme purity. Despite these promising technical findings, the review identified the need for a valid economic assessment to properly guide further work towards purifying bromelain from pineapple waste for sustainable production of commercial proteases.
    Matched MeSH terms: Peptide Hydrolases
  19. Fulltext Protease-targeting peptide-functionalized porous silicon nanoparticles for cancer fluorescence imaging
    Kanathasan JS, Palanisamy UD, Radhakrishnan AK, Chakravarthi S, Thong TB, Swamy V
    Nanomedicine (Lond), 2022 Sep;17(21):1511-1528.
    PMID: 36382634 DOI: 10.2217/nnm-2022-0017
    Background: Porous silicon (pSi) nanoparticles (NPs) functionalized with suitable targeting ligands are now established cancer bioimaging agents and drug-delivery platforms. With growing interest in peptides as tumor-targeting ligands, much work has focused on the use of various peptides in combination with pSi NPs for cancer theranostics. Here, the authors investigated the targeting potential of pSi NPs functionalized with two types of peptide, a linear 10-mer peptide and its branched (Y-shaped) equivalent, that respond to legumain activity in tumor cells. Results: In vitro experiments established that the linear peptide-pSi NP conjugate had better aqueous stability under tumor conditions and higher binding efficiency (p  0.05) of linear peptide-conjugated pSi NPs in the tumor site within 4 h compared with nonconjugated pSi NPs. These results suggest that the linear peptide-pSi NP formulation is a nontoxic, stable and efficient fluorescence bioimaging agent and potential drug-delivery platform.
    Matched MeSH terms: Peptide Hydrolases
  20. Fulltext Production, purification and evaluation of biodegradation potential of PHB depolymerase of Stenotrophomonas sp. RZS7
    Sayyed RZ, Wani SJ, Alarfaj AA, Syed A, El-Enshasy HA
    PLoS One, 2020;15(1):e0220095.
    PMID: 31910206 DOI: 10.1371/journal.pone.0220095
    There are numerous reports on poly-β-hydroxybutyrate (PHB) depolymerases produced by various microorganisms isolated from various habitats, however, reports on PHB depolymerase production by an isolate from plastic rich sites scares. Although PHB has attracted commercial significance, the inefficient production and recovery methods, inefficient purification of PHB depolymerase and lack of ample knowledge on PHB degradation by PHB depolymerase have hampered its large scale commercialization. Therefore, to ensure the biodegradability of biopolymers, it becomes imperative to study the purification of the biodegrading enzyme system. We report the production, purification, and characterization of extracellular PHB depolymerase from Stenotrophomonas sp. RZS7 isolated from a dumping yard rich in plastic waste. The isolate produced extracellular PHB depolymerase in the mineral salt medium (MSM) at 30°C during 4 days of incubation under shaking. The enzyme was purified by three methods namely ammonium salt precipitation, column chromatography, and solvent purification. Among these purification methods, the enzyme was best purified by column chromatography on the Octyl-Sepharose CL-4B column giving optimum yield (0.7993 Umg-1mL-1). The molecular weight of purified PHB depolymerase was 40 kDa. Studies on the assessment of biodegradation of PHB in liquid culture medium and under natural soil conditions confirmed PHB biodegradation potential of Stenotrophomonas sp. RZS7. The results obtained in Fourier-Transform Infrared (FTIR) analysis, High-Performance Liquid Chromatography (HPLC) study and Gas Chromatography Mass-Spectrometry (GC-MS) analysis confirmed the biodegradation of PHB in liquid medium by Stenotrophomonas sp. RZS7. Changes in surface morphology of PHB film in soil burial as observed in Field Emission Scanning Electron Microscopy (FESEM) analysis confirmed the biodegradation of PHB under natural soil environment. The isolate was capable of degrading PHB and it resulted in 87.74% biodegradation. A higher rate of degradation under the natural soil condition is the result of the activity of soil microbes that complemented the biodegradation of PHB by Stenotrophomonas sp. RZS7.
    Matched MeSH terms: Carboxylic Ester Hydrolases/biosynthesis; Carboxylic Ester Hydrolases/isolation & purification; Carboxylic Ester Hydrolases/chemistry*
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