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Tue NH, Phuc NH, Hoa PTB, Tien NQD, Loc NH. Partitioning recombinant chitinase from Nicotiana benthamiana by an aqueous two-phase system based on polyethylene glycol and phosphate salts. Int J Biol Macromol 2024; 269:131924. [PMID: 38688335 DOI: 10.1016/j.ijbiomac.2024.131924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/02/2024]
Abstract
The objectives of this study were to purify 42 kDa chitinase derived from Trichoderma asperellum SH16 produced in Nicotiana benthamiana by a polyethylene glycol (PEG)/salt aqueous two-phase system (ATPS). The specific activities of the crude chitinase and the partially purified chitinase from N. benthamiana were about 251 unit/mg and 386 unit/mg, respectively. The study found the 300 g/L PEG 6000 + 200 g/L potassium phosphate (PP) and 300 g/L PEG 6000 + 150 g/L sodium phosphate (SP) systems had the highest partitioning efficiency for each salt in primary extraction. However, among the two types of salt, PP displayed higher efficiency than SP, with a partitioning coefficient K of 4.85 vs. 3.89, a volume ratio V of 2.94 vs. 2.68, and a partitioning yield Y of approximately 95 % vs. 83 %. After back extraction, the enzymatic activity of purified chitinase was up to 834 unit/mg (PP) and 492 unit/mg (SP). The purification factors reached 3.32 (PP) and 1.96 (SP), with recovery yields of about 59 % and 61 %, respectively. SDS-PAGE and zymogram analysis showed that the recombinant chitinase was significantly purified by using ATPS. The purified enzyme exhibited high chitinolytic activity, with the hydrolysis zone's diameter being around 2.5 cm-3 cm. It also dramatically reduced the growth of Sclerotium rolfsii; the colony diameter after treatment with 60 unit of enzyme for 104 spores was only about 1 cm, compared to 3.5 cm in the control. The antifungal effect of chitinase suggests that this enzyme has great potential for applications in agricultural production as well as postharvest fruit and vegetable preservation.
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Affiliation(s)
- Nguyen Hoang Tue
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue St., Hue 49000, Viet Nam
| | - Nguyen Hoang Phuc
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue St., Hue 49000, Viet Nam
| | - Phung Thi Bich Hoa
- Department of Biology, University of Education, Hue University, 34 Le Loi St., Hue 49000, Viet Nam
| | - Nguyen Quang Duc Tien
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue St., Hue 49000, Viet Nam
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue St., Hue 49000, Viet Nam.
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Thuan NH, Tatipamula VB, Viet TT, Tien NQD, Loc NH. Bioproduction of eriodictyol by Escherichia coli engineered co-culture. World J Microbiol Biotechnol 2022; 38:112. [DOI: 10.1007/s11274-022-03294-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/22/2022] [Indexed: 10/18/2022]
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Minh NH, Trang HTQ, Van TB, Loc NH. Production and purification of nattokinase from Bacillus subtilis. FOOD BIOTECHNOL 2022. [DOI: 10.1080/08905436.2021.2005622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Nguyen Hoang Minh
- Clinical Skills Laboratory, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
| | | | - Tran Bao Van
- Department of Biotechnology, University of Sciences, Hue University, Hue, Vietnam
| | - Nguyen Hoang Loc
- Department of Biotechnology, University of Sciences, Hue University, Hue, Vietnam
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Tien NQD, Ma X, Man LQ, Chi DTK, Huy NX, Nhut DT, Rombauts S, Ut T, Loc NH. De novo whole-genome assembly and discovery of genes involved in triterpenoid saponin biosynthesis of Vietnamese ginseng ( Panax vietnamensis Ha et Grushv.). Physiol Mol Biol Plants 2021; 27:2215-2229. [PMID: 34744362 PMCID: PMC8526660 DOI: 10.1007/s12298-021-01076-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/13/2021] [Accepted: 09/17/2021] [Indexed: 05/04/2023]
Abstract
UNLABELLED Vietnamese ginseng (Panax vietnamensis Ha et Grushv.), also known as Ngoc Linh ginseng, is a high-value herb in Vietnam. Vietnamese ginseng has been proven to be effective in enhancing the immune system, human memory, anti-stress, anti-inflammatory, anti-cancer, and prevent aging. The present study reports the first draft whole-genome of Vietnamese ginseng and the identification of potential genes involved in the triterpenoid metabolic pathway. De novo whole-genome assembly was performed successfully from a data of approximately 139 Gbps of 394,802,120 high quality reads to generate 9815 scaffolds with an N50 value of 572,722 bp from the leaf of Vietnamese ginseng. The assembled genome of Vietnamese ginseng is 3,001,967,204 bp long containing 79,374 gene models. Among them, there are 55,012 genes (69.30%) were annotated by various public molecular biology databases. The potential genes involved in triterpenoid saponin biosynthesis in Vietnamese ginseng and their metabolic pathway were also predicted." Three genes encoding squalene monooxygenase isozymes in Vietnamese ginseng were cloned, sequenced and characterized. Moreover, expression levels of several key genes involved in terpenoid biosynthesis in different parts of Vietnamese ginseng were also analyzed. The SSR markers were detected by various programs from both of assembly full dataset of Vietnamese ginseng genome and predicted genes. The present work provided important data of the draft whole-genome of Vietnamese ginseng for further studies to understand the role of genes involved in ginsenoside biosynthesis and their metabolic pathway at the molecular level of this rare medicinal species. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s12298-021-01076-1.
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Affiliation(s)
- Nguyen Quang Duc Tien
- Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
- Department of Biology, Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
| | - Xiao Ma
- VIB-UGent Center for Plant Systems Biology, Ghent University, 9000 Ghent, Belgium
| | - Le Quang Man
- Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
| | - Duong Thi Kim Chi
- Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
| | | | - Duong-Tan Nhut
- Tay Nguyen Institute of Scientific Research, Vietnam Academy of Science and Technology, Dalat, 670000 Vietnam
| | - Stephane Rombauts
- VIB-UGent Center for Plant Systems Biology, Ghent University, 9000 Ghent, Belgium
| | - Tran Ut
- Ngoc Linh Ginseng and Medicinal Materials Development Center, Quang Nam Quang Ngai, 51000 Vietnam
| | - Nguyen Hoang Loc
- Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
- Department of Biology, Bioactive Compound Institute, University of Sciences, Hue University, Hue, 530000 Vietnam
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Luong NN, Tien NQD, Huy NX, Tue NH, Man LQ, Sinh DDH, Van Thanh D, Chi DTK, Hoa PTB, Loc NH. Expression of 42 kDa chitinase of Trichoderma asperellum (Ta-CHI42) from a synthetic gene in Escherichia coli. FEMS Microbiol Lett 2021; 368:6355433. [PMID: 34415008 DOI: 10.1093/femsle/fnab110] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/18/2021] [Indexed: 11/14/2022] Open
Abstract
Chitinases are enzymes that catalyze the degradation of chitin, a major component of the cell walls of pathogenic fungi and cuticles of insects, gaining increasing attention for the control of fungal pathogens and insect pests. Production of recombinant chitinase in a suitable host can result in a more pure product with less processing time and a significantly larger yield than that produced by native microorganisms. The present study aimed to express the synthetic chi42 gene (syncodChi42), which was optimized from the chi42 gene of Trichoderma asperellum SH16, in Escherichia coli to produce 42 kDa chitinase (Ta-CHI42); then determined the activity of this enzyme, characterizations and in vitro antifungal activity as well as its immunogenicity in mice. The results showed that Ta-CHI42 was overexpressed in E. coli. Analysis of the colloidal chitin hydrolytic activity of purified Ta-CHI42 on an agar plate revealed that this enzyme was in a highly active form. This is a neutral chitinase with pH stability in a range of 6-8 and has an optimum temperature of 45°C with thermal stability in a range of 25-35°C. The chitinolytic activity of Ta-CHI42 was almost completely abolished by 5 mM Zn2+ or 1% SDS, whereas it remained about haft under the effect of 1 M urea, 1% Triton X-100 or 5 mM Cu2+. Except for ions such as Mn2+ and Ca2+ at 5 mM that have enhanced chitinolytic activity; 5 mM of Na+, Fe2+ or Mg2+ ions or 1 mM EDTA negatively impacted the enzyme. Ta-CHI42 at 60 U/mL concentration strongly inhibited the growth of the pathogenic fungus Aspergillus niger. Analysis of western blot indicated that the polyclonal antibody against Ta-CHI42 was greatly produced in mice. It can be used to analyze the expression of the syncodChi42 gene in transgenic plants, through immunoblotting assays, for resistance to pathogenic fungi.
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Affiliation(s)
- Nguyen Ngoc Luong
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Nguyen Quang Duc Tien
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Nguyen Xuan Huy
- Department of Biology, University of Education, 34 Le Loi st, Hue 530000, Vietnam
| | - Nguyen Hoang Tue
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Le Quang Man
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Duong Duc Hoang Sinh
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Dang Van Thanh
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Duong Thi Kim Chi
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
| | - Phung Thi Bich Hoa
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam.,Department of Biology, University of Education, 34 Le Loi st, Hue 530000, Vietnam
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, 77 Nguyen Hue st, Hue 530000, Vietnam
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Tuan LC, Thanh LTH, Duc Huy N, Thuy Trang DT, Nhat Le BN, Nhat Linh NL, Khanh NV, Nu Bao Tien HT, Hoang Loc N. Antagonistic Activity Against Pathogenic Vibrio Isolates of Bioflocculant-Producing Bacteria Isolated from Shrimp Ponds. Pak J Biol Sci 2021; 24:1322-1332. [PMID: 34989209 DOI: 10.3923/pjbs.2021.1322.1332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
<b>Background and Objectives:</b> Biofloc culture system has been used in aquaculture as an effective technology for water treatment due to many advantages of being biodegradable and environmentally friendly. This study aims to isolate bioflocculant-producing bacteria antagonistic to pathogenic <i>Vibrio</i> species from Pacific white shrimp ponds in Thua Thien Hue, Vietnam. <b>Materials and Methods:</b> <i>Vibrio</i> isolates were isolated by screening on medium with and without antibiotics. The resistance of <i>Vibrio</i> to antimicrobial agents was assessed by Minimum Inhibitory Concentration (MIC). Bioflocs formed in shrimp cultures were used to screen bioflocculant-producing bacteria. The identification of bacteria was performed by 16S rRNA sequencing. The flocculating activity was measured by a test with kaolin clay suspension. To evaluate the antagonistic activity against <i>Vibrio</i> isolates, an agar well diffusion assay was used. <b>Results:</b> The screening results have found that <i>Vibrio</i> isolates such as <i>V. parahaemolyticus</i> KS02 and <i>V. alginolyticus</i> KS08 from shrimp ponds can be resistant to many antibiotics with the highest resistance rate up to 66.49%. Four bioflocculant-producing isolates were obtained and identified as <i>Bacillus</i> species. Among them, <i>Bacillus velezensis </i>B9 when grown in YPG medium supplemented with 3% sucrose and 0.7% peptone had the highest bioflocculation with an activity of 49.2%. Two isolates of <i>B. subtilis</i> B2 and <i>Bacillus</i> sp. B6 had quite strong antagonistic activities against vibriosis shown in the zones of inhibition on the assay plates with diameters of about 20 mm. <b>Conclusion:</b> The present study has found some <i>Bacillus</i> isolates had bioflocculant-producing efficiency and inhibited pathogenic <i>Vibrio</i> bacteria. These <i>Bacillus</i> isolates will potentially be used as inoculum for bioflocculation to improve shrimp production.
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Loc NH, Sinh DDH, Tue NH, Huy ND, Ngoc Thi TV, Ha Thanh LT. HETEROLOGOUS EXPRESSION OF A GENE ENCODING BIPHENYL 2,3-DIOXYGENASE FROM BURKHOLDERIA CEPACIA IN ESCHERICHIA COLI. J microb biotech food sci 2020. [DOI: 10.15414/jmbfs.2020.10.3.490-492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Biphenyl 2,3-dioxygenase (BphA) is an enzyme that participates in initiation step of the pathway of biphenyl degradation in bacteria. Biphenyl is an aromatic hydrocarbon including two benzene rings that causes a serious environmental pollution. This report presents the preliminary results on the cloning and expression of BphA gene of B. cepacia strains DF2 and DF4 which were isolated from dioxin contaminated soil in Vietnam. The coding DNA sequences of BphA genes are 897 bp long and 99% identical. Recombinant BphA enzyme (33 kDa) has strongly expressed in E. coli M15 after induction of 0.5 mM IPTG for 4 h at 37ºC.
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Ngoc Thi TV, Hoang Sinh DD, Ha Thanh LT, Huy ND, Tue NH, Shintani M, Kimbara K, Loc NH. Cloning, expression and characterization of catechol 1,2-dioxygenase from Burkholderia cepacia. J GEN APPL MICROBIOL 2020; 66:188-194. [PMID: 31723074 DOI: 10.2323/jgam.2019.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The present study reports on the cloning, expression and characterization of catechol 1,2-dioxygenase (CAT) of bacterial strains isolated from dioxin-contaminated soils in Vietnam. Two isolated bacterial strains DF2 and DF4 were identified as Burkholderia cepacia based on their 16S rRNA sequences. Their genes coding CAT was amplified with a specific pair of primers. Recombinant CAT (rCAT) was expressed in E. coli M15 cells and its activity was confirmed by the detection of cis,cis-muconic acid, a product from catechol, by high-performance liquid chromatography (HPLC) analysis. The rCAT of DF4 had an optimal pH and temperature of 7 and 30°C, respectively. Metal ions, such as Zn2+ and Mn2+, and surfactants, such as SDS, Tween 20 and Triton X100, strongly inhibited enzyme activity, while K+ slightly increased the activity.
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Affiliation(s)
- Tran Vu Ngoc Thi
- Department of Applied Chemistry and Biochemical Engineering, Shizuoka University.,Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University
| | - Duong Duc Hoang Sinh
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University
| | - Le Thi Ha Thanh
- Department of Applied Chemistry and Biochemical Engineering, Shizuoka University.,Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University
| | - Nguyen Duc Huy
- Department of Microbial Biotechnology, Institute of Biotechnology, Hue University
| | - Nguyen Hoang Tue
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University
| | - Masaki Shintani
- Department of Applied Chemistry and Biochemical Engineering, Shizuoka University
| | - Kazuhide Kimbara
- Department of Applied Chemistry and Biochemical Engineering, Shizuoka University
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University
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Miyazawa D, Thanh LTH, Tani A, Shintani M, Loc NH, Hatta T, Kimbara K. Isolation and Characterization of Genes Responsible for Naphthalene Degradation from Thermophilic Naphthalene Degrader, Geobacillus sp. JF8. Microorganisms 2019; 8:microorganisms8010044. [PMID: 31878343 PMCID: PMC7023095 DOI: 10.3390/microorganisms8010044] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/18/2019] [Accepted: 12/19/2019] [Indexed: 11/26/2022] Open
Abstract
Geobacillus sp. JF8 is a thermophilic biphenyl and naphthalene degrader. To identify the naphthalene degradation genes, cis-naphthalene dihydrodiol dehydrogenase was purified from naphthalene-grown cells, and its N-terminal amino acid sequence was determined. Using a DNA probe encoding the N-terminal region of the dehydrogenase, a 10-kb DNA fragment was isolated. Upstream of nahB, a gene for dehydrogenase, there were two open reading frames which were designated as nahAc and nahAd, respectively. The products of nahAc and nahAd were predicted to be alpha and beta subunit of ring-hydroxylating dioxygenases, respectively. Phylogenetic analysis of amino acid sequences of NahB indicated that it did not belong to the cis-dihydrodiol dehydrogenase group that includes those of classical naphthalene degradation pathways. Downstream of nahB, four open reading frames were found, and their products were predicted as meta-cleavage product hydrolase, monooxygenase, dehydrogenase, and gentisate 1,2-dioxygenase, respectively. A reverse transcriptase-PCR analysis showed that transcription of nahAcAd was induced by naphthalene. These findings indicate that we successfully identified genes involved in the upper pathway of naphthalene degradation from a thermophilic bacterium.
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Affiliation(s)
- Daisuke Miyazawa
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan; (D.M.); (A.T.)
| | - Le Thi Ha Thanh
- Department of Environment and Energy System, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8011, Japan;
- Institute of Bioactive Compounds, University of Sciences, Hue University, Hue, Thua Thien Hue 530000, Vietnam;
| | - Akio Tani
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan; (D.M.); (A.T.)
| | - Masaki Shintani
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, Shizuoka 422-8529, Japan
- Correspondence: (M.S.); (K.K.); Tel.: +81-53-478-1181 (M.S.); +81-53-478-1170 (K.K.)
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds, University of Sciences, Hue University, Hue, Thua Thien Hue 530000, Vietnam;
| | - Takashi Hatta
- Department of Biomedical Engineering, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 703-8232, Japan;
| | - Kazuhide Kimbara
- Department of Environment and Energy System, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8011, Japan;
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Correspondence: (M.S.); (K.K.); Tel.: +81-53-478-1181 (M.S.); +81-53-478-1170 (K.K.)
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Loc NH, Huy ND, Quang HT, Lan TT, Thu Ha TT. Characterisation and antifungal activity of extracellular chitinase from a biocontrol fungus, Trichoderma asperellum PQ34. Mycology 2019; 11:38-48. [PMID: 32128280 PMCID: PMC7033689 DOI: 10.1080/21501203.2019.1703839] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 09/10/2019] [Indexed: 11/27/2022] Open
Abstract
Trichoderma species were known as biological control agents against phytopathogenic fungi because they produce a variety of chitinases. Chitinases are hydrolytic enzymes that break down glycosidic bonds in chitin, a major component of the cell walls of fungi. The present study shows that extracellular chitinase activity reached a maximum value of approximately 22 U/mL after 96 h of T. asperellum PQ34 strain culture. The optimal temperature and pH of enzyme are 40°C and 7, respectively, whereas the thermal and pH stability range from 25°C to 50°C and 4 to 10, respectively. Chitinase at 60 U/mL inhibited nearly completely in vitro growth of Colletotrichum sp. (about 95%) and Sclerotium rolfsii (about 97%). In peanut plants, 20 U/mL of chitinase significantly reduced the incidence of S. rolfsii infection compared to controls. The fungal infection incidence of seeds before germination and 30 days after germination was only 2.22% and 2.38%, while the control was 13.33% and 17.95%. Besides, chitinase from T. asperellum PQ34 can also prevent anthracnose that is caused by Colletotrichum sp. on both mango and chilli fruits up to 72 h after enzyme pre-treatment at 40 U/mL. In mango and chilli fruits infected with anthracnose, 40 U/mL dose of chitinase inhibited the growth of fungi after 96 h of treatment, the diameter of lesion was only 0.88 cm for mango and 1.45 cm for chilli, while the control was 1.67 cm and 2.85 cm, respectively.
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Affiliation(s)
- Nguyen Hoang Loc
- Institute of Bioactive Compounds and Department of Biotechnology, University of Sciences, Hue University, Hue, Vietnam
| | - Nguyen Duc Huy
- Department of Applied Biology and Biotechnology, Institute of Biotechnology, Hue University, Hue, Vietnam
| | - Hoang Tan Quang
- Department of Applied Biology and Biotechnology, Institute of Biotechnology, Hue University, Hue, Vietnam
| | - Tran Thuy Lan
- Department of Applied Biology and Biotechnology, Institute of Biotechnology, Hue University, Hue, Vietnam
| | - Tran Thi Thu Ha
- Department of Plant Protection, University of Agriculture and Forestry, Hue University, Hue, Vietnam
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Thanh LTH, Thi TVN, Shintani M, Moriuchi R, Dohra H, Loc NH, Kimbara K. Isolation and characterization of a moderate thermophilic Paenibacillus naphthalenovorans strain 4B1 capable of degrading dibenzofuran from dioxin-contaminated soil in Vietnam. J Biosci Bioeng 2019; 128:571-577. [DOI: 10.1016/j.jbiosc.2019.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/19/2019] [Accepted: 05/07/2019] [Indexed: 10/26/2022]
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Lan TTP, Huy ND, Luong NN, Nghi NV, Tan TH, Quan LV, Loc NH. Identification and Characterization of Genes in the Curcuminoid Pathway of Curcuma zedoaria Roscoe. Curr Pharm Biotechnol 2018; 19:839-846. [DOI: 10.2174/1389201019666181008112244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 09/28/2018] [Accepted: 10/01/2018] [Indexed: 11/22/2022]
Affiliation(s)
- Truong Thi Phuong Lan
- Institute of Bioactive Compounds, College of Sciences, Hue University, 77 Nguyen Hue St., Hue, Vietnam
| | - Nguyen Duc Huy
- Institute of Biotechnology, Hue University, Phu Thuong, Phu Vang, Thua Thien Hue, Vietnam
| | - Nguyen Ngoc Luong
- Institute of Bioactive Compounds, College of Sciences, Hue University, 77 Nguyen Hue St., Hue, Vietnam
| | - Nguyen Van Nghi
- Institute of Bioactive Compounds, College of Sciences, Hue University, 77 Nguyen Hue St., Hue, Vietnam
| | - Trinh Huu Tan
- Institute of Biotechnology, Hue University, Phu Thuong, Phu Vang, Thua Thien Hue, Vietnam
| | - Le Viet Quan
- Institute of Bioactive Compounds, College of Sciences, Hue University, 77 Nguyen Hue St., Hue, Vietnam
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds, College of Sciences, Hue University, 77 Nguyen Hue St., Hue, Vietnam
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Abstract
CONTEXT Eurycomanone is found in the Eurycoma longifolia Jack (Simaroubaceae) tree, exhibits significant antimalarial activity, improves spermatogenesis, suppresses expression of lung cancer cell tumour markers and regulates signalling pathways involved in proliferation, cell death and inflammation. OBJECTIVES Establishment of cell suspension culture of E. longifolia to determine the eurycomanone accumulation during cultures. MATERIALS AND METHODS Callus of E. longifolia was cultured in MS medium supplemented with 0.8% agar, 30/L sucrose, 1.25 mg/L NAA and 1 mg/L KIN for biomass production. Cell suspension culture was established by transferring friable calli to the same medium without agar. Eurycomanone content during cell culture was determined by HPLC with a C18 column, flow rate of 0.8 mL/min, run time of 17.5 min, detector wavelength of 254 nm. The stationary phase was silica gel and the mobile phase was acetonitric:H2O. Roots of 5 year-old trees were used as the control. RESULTS The cells from 3 g of inoculum increased in biomass with a maximum value of 16 g fresh weight (0.7 g dry weight) at 14th day of culture. The cell growth then decreased from day 14 to day 20. Eurycomanone was produced during culture from the beginning to 20th day, its highest content (1.7 mg/g dry weight) also obtained at 14th day (the control is 2.1 mg/g dry weight). DISCUSSION AND CONCLUSIONS Cell suspension culture of E. longifolia is a suitable procedure to produce eurycomanone. The yield of eurycomanone biosynthesis in 14 days-old cells are relatively high, approximately 0.8 times the control.
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Affiliation(s)
- Nguyen Huu Nhan
- College of Sciences, Institute of Bioactive Compounds, Hue University, Hue, Vietnam
- College of Food Industry, Da Nang, Vietnam
| | - Nguyen Hoang Loc
- College of Sciences, Institute of Bioactive Compounds, Hue University, Hue, Vietnam
- CONTACT Nguyen Hoang Loc College of Sciences, Institute of Bioactive Compounds, Hue University, Hue, Vietnam
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Loc NH. Accumulation of madecassoside - a major component of centelloside - in centella (Centella asiatica (L.) Urban) cells elicited by salicylic acid. PERIOD BIOL 2017. [DOI: 10.18054/pb.v119i1.4386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Loc NH, Giang NT, Huy ND. Effect of salicylic acid on expression level of genes related with isoprenoid pathway in centella (Centella asiatica (L.) Urban) cells. 3 Biotech 2016; 6:86. [PMID: 28330156 PMCID: PMC4779453 DOI: 10.1007/s13205-016-0404-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 02/14/2016] [Indexed: 12/04/2022] Open
Abstract
In this study, we report the expression level of CaSQS, CabAS and CaCYS, the genes involved in phytosterol and triterpene metabolic pathway of centella (Centella asiatica (L.) Urban), in cells elicited with salicylic acid (50–200 µM). Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis indicated CaSQS, CabAS, and CaCYS genes expressed in both the wild-type and cultured cells (with and without elicitation). In elicited cells, expressions of CaSQS, CabAS, and CaCYS genes showed strong dependence on salicylic acid concentration and elicitation day. The highest expression of CabAS gene was found in the cells elicited with 100 µM salicylic acid on day 10 of inoculation. Salicylic acid treatment (50–200 µM) decreased expression level of CaCYS and CaSQS genes in elicited cells compared with the control.
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Phuoc LH, Hu B, Wille M, Hien NT, Phuong VH, Tinh NTN, Loc NH, Sorgeloos P, Bossier P. Priming the immune system of Penaeid shrimp by bacterial HSP70 (DnaK). J Fish Dis 2016; 39:555-564. [PMID: 26096017 DOI: 10.1111/jfd.12388] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/13/2015] [Accepted: 04/14/2015] [Indexed: 06/04/2023]
Abstract
This study was conducted to test the effect of DnaK on priming immune responses in Penaeid shrimp. Juvenile-specific pathogen-free (SPF) P. vannamei shrimp were injected with 0.05 μg recombinant DnaK. One hour post-DnaK priming, a non-lethal dose of Vibrio campbellii (10(5) CFU shrimp(-1)) was injected. Other treatments include only DnaK or V. campbellii injection or control with blank inocula. The haemolymph of three shrimp from each treatment was collected at 1.5, 6, 9 and 12 h post-DnaK priming (hpp). It was verified that injection with DnaK and V. campbellii challenge affected the transcription of 3 immune genes, transglutaminase-1 (TGase-1), prophenoloxidase-2 (proPO-2) and endogenous HSP70 (lvHSP70). In P. monodon, shrimp were first injected with DnaK at a dose of 10 μg shrimp(-1) and one hour later with 10(6) CFU of V. harveyi (BB120) shrimp(-1). Shrimp injected with DnaK showed a significant increase in proPO expression compared to the control (P < 0.05). Yet a double injection (DnaK and Vibrio) seemed to cause an antagonistic response at the level of expression, which was not equalled at the level of PO activity. Those results suggest that DnaK is able to modulate immune responses in P. vannamei and P. monodon.
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Affiliation(s)
- L H Phuoc
- Research Institute for Aquaculture No2, Ho Chi Minh City, Vietnam
| | - B Hu
- Laboratory for Aquaculture & Artemia Reference Center, Ghent University, Gent, Belgium
| | - M Wille
- Laboratory for Aquaculture & Artemia Reference Center, Ghent University, Gent, Belgium
| | - N T Hien
- Research Institute for Aquaculture No2, Ho Chi Minh City, Vietnam
| | - V H Phuong
- Research Institute for Aquaculture No2, Ho Chi Minh City, Vietnam
| | - N T N Tinh
- Research Institute for Aquaculture No2, Ho Chi Minh City, Vietnam
| | - N H Loc
- Research Institute for Aquaculture No2, Ho Chi Minh City, Vietnam
| | - P Sorgeloos
- Laboratory for Aquaculture & Artemia Reference Center, Ghent University, Gent, Belgium
| | - P Bossier
- Laboratory for Aquaculture & Artemia Reference Center, Ghent University, Gent, Belgium
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Loc NH, Ngoc LMT, Tam DT, Quang HT, Lan DTB, Long PT. Cloning and expression of gene FanC-2NT encoding K99-2NT fimbrial antigen of enterotoxigenic Escherichia coli from diarrheic post-weaning piglets. PERIOD BIOL 2016. [DOI: 10.18054/pb.v117i3.3090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background and Purpose: The K99 (F5) is one pilus adhesin that mediates the attachment of enterotoxigenic E. coli (ETEC) strains to small intestines to cause to diarrhea in piglets, lambs and newborn calves. In this work, we carried out cloning and expression of the mature peptide of FanC subunit, K99 fimbriae, one of the most common adhesive antigens in E. coli. Materials and Methods: E. coli 2NT strain was isolated from fecal samples of post-weaning piglets with diarrhea. The coding sequence of the mature peptide of K99-2NT subunit was isolated by PCR amplification and cloned into pGEM®-T Easy vector for sequencing using fluorescent dideoxy-terminator method. Expression of K99-2NT protein which was inserted into pET200/D-TOPO vector induced with IPTG. The PCR product and expression level of protein was examined by agarose gel electrophoresis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively. Results and Conclusions: We cloned and expressed successfully the mature peptide of K99 subunit with molecular weight of approximately 17.5 kDa from E. coli 2NT strain (named K99-2NT). Nucleotide sequence of the K99-2NT subunit coding region of fanC-2NT gene is 477 bp in length and is 99% similarity with that of fanC gene (accession no: M35282). Highest expression level occurred after 12 h of induction with 0.75 mM IPTG at 37oC. This subunit antigen will be tested for immune response of rat in the next time.
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Loc NH. Cloning and expression of gene FanC-2NT encoding K99-2NT fimbrial antigen of enterotoxigenic Escherichia coli from diarrheic post-weaning piglets. PERIOD BIOL 2016. [DOI: 10.18054/pb.2015.117.3.3090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Loc NH, Ngoc LMT, Quang HT, Huy ND, Luong NN. Cloning and expression of two genes coding endo-β-1,4-glucanases from Trichoderma asperellum PQ34 in Pichia pastoris. Chemical Papers 2016. [DOI: 10.1515/chempap-2015-0210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractTwo genes coding endo-β-1,4-glucanases were cloned from Trichoderma asperellum PQ34 which was isolated from Thua Thien Hue province, Vietnam. The expression of these genes in Pichia pastoris produced two enzymes with molecular masses of approximately 46 kDa (about 42 kDa of enzymes and 4 kDa of signal peptide). The effects of induction time and temperature, inducer concentration, and culture medium on the endo-β-1,4-glucanase activity were investigated. The results showed that the highest total activities of two endo-β-1,4-glucanases were approximately 4.7 × 10
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Huy ND, Nguyen CL, Park HS, Loc NH, Choi MS, Kim DH, Seo JW, Park SM. Characterization of a novel manganese dependent endoglucanase belongs in GH family 5 from Phanerochaete chrysosporium. J Biosci Bioeng 2015; 121:154-9. [PMID: 26173955 DOI: 10.1016/j.jbiosc.2015.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 05/31/2015] [Accepted: 06/18/2015] [Indexed: 01/22/2023]
Abstract
The cDNA encoding a putative glycoside hydrolase family 5, which has been predicted to be an endoglucanase (PcEg5A), was cloned from Phanerochaete chrysosporium and expressed in Pichia pastoris. PcEg5A contains a carbohydrate-binding domain and two important amino acids, E209 and E319, playing as proton donor and nucleophile in substrate catalytic domain. SDS-PAGE analysis indicated that the recombinant endoglucanase 5A (rPcEg5A) has a molecular size of 43 kDa which corresponds with the theoretical calculation. Optimum pH and temperature were found to be 4.5-6.0, and 50°C-60°C, respectively. Moreover, rPcEg5A exhibited maximal activity in the pH range of 3.0-8.0, whereas over 50% of activity still remained at 20°C and 80°C. rPcEg5A was stable at 60°C for 12 h incubation, indicating that rPcEg5A is a thermostable enzyme. Manganese ion enhanced the enzyme activity by 77%, indicating that rPcEg5A is a metal dependent enzyme. The addition of rPcEg5A to cellobiase (cellobiohydrolase and β-glucosidase) resulted in a 53% increasing saccharification of NaOH-pretreated barley straw, whereas the glucose release was 47% higher than that cellobiase treatment alone. Our study suggested that rPcEg5A is an enzyme with great potential for biomass saccharification.
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Affiliation(s)
- Nguyen Duc Huy
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea; Institute of Biotechnology, Hue University, Hue 530000, Viet Nam
| | - Cu Le Nguyen
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea
| | - Han-Sung Park
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea
| | | | - Myoung-Suk Choi
- Institute of Molecular Biology and Genetics, College of Natural Sciences, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea
| | - Dae-Hyuk Kim
- Institute of Molecular Biology and Genetics, College of Natural Sciences, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea
| | - Jeong-Woo Seo
- Applied Microbiology Research Center, Bio-Materials Research Institute, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeongeup, Jeonbuk 580-185, Republic of Korea
| | - Seung-Moon Park
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea.
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Loc NH, Ngoc LMT, Lan TT, Viet LQ, Thao LD, Quang HT, Lan DTB, Long PT. Cloning and Expression of Genes Encoding F107-C and K88-1NT Fimbrial Proteins of Enterotoxigenic Escherichia coli from Piglets. Indian J Microbiol 2013; 53:488-91. [PMID: 24426156 DOI: 10.1007/s12088-013-0386-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Accepted: 03/06/2013] [Indexed: 11/27/2022] Open
Abstract
We cloned two genes coding F107-C and K88-1NT fimbrial subunits from strains E. coli C and 1NT isolated from Thua Thien Hue province, Vietnam. The mature peptide of faeG gene from strain E. coli 1NT (called faeG-1NT) is 100 % similarity with faeG gene, while the CDS of fedA gene from strain C (called fedA-C) has a similarity of 97 % with the fedA gene. Expression of the faeG-1NT and fedA-C genes in E. coli BL21 Star™ (DE3) produced proteins of ~31 and 22 kDa, respectively. The effect of IPTG concentration on the K88-1NT and F107-C fimbriae production was investigated. The results showed that 0.5 mM IPTG is suitable for higher expression of K88-1NT subunit, while 0.75 mM IPTG strongly stimulated expression of F107-C subunit. The optimal induction time for expression was also examined. Generally, highest expression of K88-1NT subunit occurred after 6 h of induction, while that of F107-C subunit is after 14 h.
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Affiliation(s)
- Nguyen Hoang Loc
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Le My Tieu Ngoc
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Tran Thuy Lan
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Le Quoc Viet
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Le Duc Thao
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Hoang Tan Quang
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Dinh Thi Bich Lan
- Institute of Resources, Environment and Biotechnology, Hue University, Hue, 47000 Vietnam
| | - Phung Thang Long
- College of Agriculture and Forestry, Hue University, Hue, 47000 Vietnam
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Loc NH, Quang HT, Hung NB, Huy ND, Phuong TTB, Ha TTT. Trichoderma asperellumChi42 Genes Encode Chitinase. Mycobiology 2011; 39:182-6. [PMID: 22783101 PMCID: PMC3385114 DOI: 10.5941/myco.2011.39.3.182] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 08/09/2011] [Indexed: 05/03/2023]
Abstract
Four Trichoderma strains (CH2, SH16, PQ34, and TN42) were isolated from soil samples collected from Quang Tri and Thua Thien Hue provinces in Vietnam. The strains exhibited high chitinolytic secretion. Strain PQ34 formed the largest zone of chitinase-mediated clearance (> 4 cm in diameter) in agar containing 1% (w/v) colloidal chitin. Analysis of the internal transcribed spacer regions of these strains indicated that they were Trichoderma asperellum. The molecular weights of the chitinases were approximately 42 kDa. Chitinase genes (chi42) of T. asperellum strains TN42, CH2, SH16, and PQ34 were 98~99% homologous to the ech42 gene of T. harzianum CB-Pin-01 (accession No. DQ166036). The deduced amino acid sequences of both T. asperellum strains SH16 and TN42 shared 100% similarity.
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Affiliation(s)
- Nguyen Hoang Loc
- Institute of Resources, Environment and Biotechnology, Hue University, 27 Phan Dinh Phung St., Hue, Vietnam
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Loc NH, Thinh LT, Yang MS, Kim TG. Highly expressed cholera toxin B subunit in the fruit of a transgenic tomato (Lycopersicon esculentum L.). BIOTECHNOL BIOPROC E 2011. [DOI: 10.1007/s12257-010-0195-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Loc NH, Mien NTT, Thuy DTB. Purification of extracellular α-amylase from Bacillus subtilis by partitioning in a polyethylene glycol/potassium phosphate aqueous two-phase system. ANN MICROBIOL 2010. [DOI: 10.1007/s13213-010-0100-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Loc NH, Bach NH, Kim TG, Yang MS. Tissue culture and expression of Escherichia coli heat-labile enterotoxin B subunit in transgenic Peperomia pellucida. Protein Expr Purif 2010; 72:82-6. [DOI: 10.1016/j.pep.2010.02.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 02/16/2010] [Accepted: 02/16/2010] [Indexed: 10/19/2022]
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