1
|
Baek HW, Bae JH, Lee YG, Kim SA, Min W, Shim S, Han NS, Seo JH. Dynamic interactions of lactic acid bacteria in Korean sourdough during back-slopping process. J Appl Microbiol 2021; 131:2325-2335. [PMID: 33797823 DOI: 10.1111/jam.15097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 12/04/2020] [Revised: 03/19/2021] [Accepted: 03/28/2021] [Indexed: 11/28/2022]
Abstract
AIMS This study aimed to clarify the cause of quality reduction in Korean sourdough after successive back-slopping. METHODS AND RESULTS We investigated the dynamic changes in lactic acid bacteria during the back-slopping process using genetic fingerprinting techniques. During the initial propagation phases, the dominant lactic acid bacteria were Fructilactobacillus sanfranciscensis (<5 log CFU per g sourdough), Latilactobacillus curvatus (9·5 log CFU per g sourdough) and Levilactobacillus brevis (6·5 log CFU per g sourdough). However, after the 11th propagation, F. sanfranciscensis became more prominent (>9·0 log CFU per g sourdough), whereas L. curvatus and L. brevis rapidly decreased. Monitoring these bacteria in the co-culture system revealed that acid-tolerant F. sanfranciscensis rapidly utilized maltose (1·65 g l-1 h-1 ) and produced large amounts of lactic acid, whereas L. brevis and L. curvatus consumed maltose slowly and L. curvatus was poorly tolerant to lactic acid. CONCLUSION The results indicate that competition exists between the lactic acid bacteria in sourdough during the back-slopping process, and microbial succession by acid-tolerant species results in quality reduction of sourdough. SIGNIFICANCE AND IMPACT OF THE STUDY This study uncovered the cause of microbial changes during the propagation of Korean sourdough and proposed a strategy to develop starters to produce high-quality bakery products.
Collapse
Affiliation(s)
- H-W Baek
- Department of Agricultural Biotechnology, Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea
| | - J-H Bae
- Brain Korea 21 Center for Bio-Health Industry, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Republic of Korea
| | - Y-G Lee
- Department of Agricultural Biotechnology, Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea
| | - S-A Kim
- Brain Korea 21 Center for Bio-Health Industry, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Republic of Korea
| | - W Min
- Department of Food Science and Development, Kyungil University, Gyeongsan, Republic of Korea
| | - S Shim
- Research Institute of Food and Biotechnology, SPC Group, Seoul, Republic of Korea
| | - N S Han
- Brain Korea 21 Center for Bio-Health Industry, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Republic of Korea
| | - J-H Seo
- Department of Agricultural Biotechnology, Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea.,Research Institute of Food and Biotechnology, SPC Group, Seoul, Republic of Korea
| |
Collapse
|
2
|
Liu S, Song M, Yun W, Lee J, Lee C, Kwak W, Han N, Kim H, Cho J. Effects of oral administration of different dosages of carvacrol essential oils on intestinal barrier function in broilers. J Anim Physiol Anim Nutr (Berl) 2018; 102:1257-1265. [PMID: 29968943 DOI: 10.1111/jpn.12944] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [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: 12/04/2017] [Revised: 04/24/2018] [Accepted: 05/18/2018] [Indexed: 11/28/2022]
Abstract
Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28-day-old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 μl carvacrol essential oils at 18:00 hr every day during the 2-week experimental period. As a result of which, the gene expression of the occludin, claudin-1, claudin-5, ZO-1 and ZO-2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 μl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 μl was more effective than that of 200 μl.
Collapse
Affiliation(s)
- ShuDong Liu
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| | - MinHo Song
- Department of Animal Science and Biotechnology, Chungnam National University, Daejeon, Korea
| | - Won Yun
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| | - JiHwan Lee
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| | - ChangHee Lee
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| | - WooGi Kwak
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| | - NamSoo Han
- Department of Food Science and Biotechnology, Chungbuk National University, Cheongju-si, Korea
| | - HyeunBum Kim
- Department of Animal Resource and Science, Dankook University, Cheonan, Korea
| | - JinHo Cho
- Division of Food and Animal Science, Chungbuk National University, Cheongju-si, Korea
| |
Collapse
|
3
|
Shin NR, Moon JS, Shin SY, Li L, Lee YB, Kim TJ, Han NS. Isolation and characterization of human intestinal Enterococcus avium EFEL009 converting rutin to quercetin. Lett Appl Microbiol 2015; 62:68-74. [PMID: 26505733 DOI: 10.1111/lam.12512] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [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: 06/18/2015] [Revised: 10/14/2015] [Accepted: 10/14/2015] [Indexed: 11/27/2022]
Abstract
UNLABELLED Quercetin is a flavonol believed to have beneficial effects on human health. Rutin, found in many plants, fruits and vegetables, is metabolized by human intestinal bacteria and converted to quercetin, where it is absorbed through the intestinal epithelium. This study aimed to isolate and characterize human intestinal bacteria capable of converting rutin to quercetin. A bacterium that can metabolize rutin was isolated from human faecal samples and identified by 16S rRNA gene sequencing. The whole-cell enzymatic activities on flavonoid glycoside and the conversion profiles of the isolate were also analysed. The bacterium was identified as Enterococcus avium EFEL009 and was shown to convert rutin to isoquercetin and then to quercetin under anaerobic conditions. Microscopic analysis revealed short chains of cocci with diameters of approx. 1 μm. β-Glucosidase was shown to be constitutively expressed in Ent. avium, while α-rhamnosidase was expressed following induction by rutin. Both enzymes were mainly localized to the cell surface. This study is the first report on the isolation of a quercetin-producing Ent. avium FEEL009, which could be a potential industrial starter bacterium. SIGNIFICANCE AND IMPACT OF THE STUDY Quercetin is a member of the flavonoids family reported to have better cytoprotective abilities, stronger inhibition of lipopolysaccharide-induced nitric oxide production, and better chemoprevention than rutin. This is the first report on the isolation and characterization of Enterococcus avium EFEL009 from the human intestine which is capable of converting rutin to quercetin.
Collapse
Affiliation(s)
- N R Shin
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| | - J S Moon
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| | - S-Y Shin
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| | - L Li
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| | - Y B Lee
- Central Research Institute, Dr. Chung's Food Co. Ltd., Cheongju, Korea
| | - T-J Kim
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| | - N S Han
- Division of Animal, Horticultural, and Food Sciences, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University, Cheongju, Korea
| |
Collapse
|
4
|
Jang SK, Lee DI, Kim ST, Kim GH, Park DW, Park JY, Han D, Choi JK, Lee YB, Han NS, Kim YB, Han J, Joo SS. The anti-aging properties of a human placental hydrolysate combined with dieckol isolated from Ecklonia cava. BMC Complement Altern Med 2015; 15:345. [PMID: 26438076 PMCID: PMC4594884 DOI: 10.1186/s12906-015-0876-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 09/23/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUNDS In the present study, we aimed to examine the anti-aging properties of human placental hydrolysate (HPE) and dieckol (DE) from Ecklonia cava against free radical scavenging, muscle hypertrophy-related follistatin mRNA expression, amelioration of cognition-related genes and proteins, inhibition of collagenase-regulating genes, and elastinase activity. METHODS The anti-aging effects were examined in human fibroblast (CCD986sk), mouse myoblast (C2C12), and neuroblastoma (N2a) cell models, by employing various assays such as 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) scavenging, hydroxyl radical-mediated oxidation, quantitative real-time polymerase chain reaction, enzyme activity, and immunocytochemistry observation. RESULTS Our results show that HPE combined with DE (HPE:DE) strongly scavenged DPPH radicals and protected proteins against degradation by hydroxyl radical attack. HPE:DE effectively inhibited matrix metalloproteinase-1 expression, protein kinase C alpha expression, and elastinase activity. Furthermore, HPE:DE improved the expression of cognition-related genes (choline acetyltransferase and vesicular acetylcholine transporter). These events may proactively contribute to retard the aging processes and the abrupt physiological changes probably induced by mitochondrial dysfunction with aging. CONCLUSIONS Based on these findings, we conclude that the combined treatment of HPE:DE may be useful for anti-aging therapy in which the accumulation of oxidative damage is the main driving force.
Collapse
Affiliation(s)
- Su Kil Jang
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea
| | - Do Ik Lee
- College of Pharmacy, Chung-Ang University, Heuksuk-dong, Dongjak-gu, Seoul, 156-756, Republic of Korea
| | - Seung Tae Kim
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea
| | - Gwang Hoon Kim
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea
| | - Da Woon Park
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea
| | - Jung Youl Park
- Industry-Academic Cooperation Foundation, Hanbat National University, Daejeon, 305-719, Republic of Korea
| | - Daehee Han
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea
| | - Jae Kwon Choi
- Central Research Institute, Dr. Chung's Food Co. Ltd., Chungbuk, 361-782, Republic of Korea
| | - Yoon-bok Lee
- Central Research Institute, Dr. Chung's Food Co. Ltd., Chungbuk, 361-782, Republic of Korea
| | - Nam-Soo Han
- Chungbuk National University, Chungbuk, 361-763, Republic of Korea
| | - Yun Bae Kim
- Chungbuk National University, Chungbuk, 361-763, Republic of Korea
| | - Jeongsu Han
- DF-Dr. Han Biotech., Shaoyaojubeili, Chaoyang District, Beijing, 10029, China
| | - Seong Soo Joo
- Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon, 210-702, Republic of Korea.
| |
Collapse
|
5
|
Lu ZB, Tian JC, Han NS, Hu C, Peng YF, Stanley D, Ye GY. No direct effects of two transgenic Bt rice lines, T1C-19 and T2A-1, on the arthropod communities. Environ Entomol 2014; 43:1453-1463. [PMID: 25203669 DOI: 10.1603/en14089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A 2-yr field trial was conducted to assess the impacts of two new transgenic Bt rice lines, T1C-19 expressing Cry1C protein and T2A-1 expressing Cry2A protein, on the arthropod community sampled via vacuum. All the arthropods were classified into five guilds, including herbivores, parasitoids, predators, detritivores, and others. The seasonal density and dominance distribution of each guild and community-level indices (species richness, Shannon-Wiener diversity index, Simpson diversity index, and evenness index) were compared among rice types. Principal response curves were used to investigate the differences of entire arthropod community of Bt rice plots relative to non-Bt rice plots. The results showed no significant difference was detected in the community-level indices and dominance distribution of guilds between Bt and non-Bt rice plots. The seasonal density of herbivores, detritivores, and others as well as density of the arthropod overall community were also not significantly affected by rice types in either year, although the density of predators and parasitoids in Bt rice plots was significantly lower than those in non-Bt rice plots. The lower abundances of Braconidae, Eulophidae, Cyrtorhinus lividipennis (Reuter) (Hemiptera: Miridae), and Theridiidae in Bt rice plots are likely attributed to the lower abundances of prey species or hosts. Principal response curves revealed that arthropod community in Bt was similar with that in non-Bt rice plots. In conclusion, our findings indicate that these two tested Bt rice lines had no marked negative effects on the arthropod community in the paddy fields.
Collapse
Affiliation(s)
- Z B Lu
- State Key Laboratory of Rice Biology & Key Laboratory of Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | | | | | | | | | | | | |
Collapse
|
6
|
Li L, Shin SY, Lee KW, Han NS. Production of natural antimicrobial compound D-phenyllactic acid using Leuconostoc mesenteroides ATCC 8293 whole cells involving highly active D-lactate dehydrogenase. Lett Appl Microbiol 2014; 59:404-11. [PMID: 24888766 DOI: 10.1111/lam.12293] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [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: 03/17/2014] [Revised: 05/19/2014] [Accepted: 05/28/2014] [Indexed: 11/28/2022]
Abstract
Phenyllactic acid (PLA) is an antimicrobial compound naturally synthesized in various fermented foods and its D-form of PLA is known to be more active than the L-isomer. In this study, Leuconostoc mesenteroides ATCC 8293 cells, elaborating D-lactate dehydrogenase (D-ldh) were used to produce D-PLA from phenylpyruvic acid (PPA). When cultured in the presence of PPA (≤50 mmol l(-1)), growing cells produced a maximum yield of 35 mmol l(-1) of D-PLA, and the yields were between 75·2 and 83·3%. Higher conversion yields were obtained at pH 6·0-7·0 when growing cells were used, while the optimum pH range was broader for resting cells. The time required for the complete conversion of PPA into PLA could be shortened to 3 h using resting cells. D-ldh, an enzyme encoded by the LEUM_1756 gene of Leuc. mesenteroides ATCC 8293, was found to be responsible for the conversion of PPA into PLA. The Km and kcat values of the enzyme for PPA were found to be 15·4 mmol l(-1) and 5645 s(-1), respectively. The conditions required for the efficient production of D-PLA were optimized for both growing and resting cells of Leuc. mesenteroides, with special emphasis on achieving high stereoselectivity and conversion yield. Significance and impact of the study: This is the first study on the production of D-phenyllactic acid, which is a natural antimicrobial compound, from phenylpyruvate using Leuconostoc mesenteroides cells. The strain, ATCC 8293, that was used in the study, possesses high stereoselectivity and delivers a high yield. Therefore, it might be a promising candidate for use in large-scale production facilities and in fermented foods.
Collapse
Affiliation(s)
- L Li
- Brain Korea 21 Center for Bio-Resource Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
| | | | | | | |
Collapse
|
7
|
Kang H, Moon J, Han N. Leuconostoc citreum 61 isolated from Kimchi, a Korean traditional food, decreases IgE synthesis via suppression of non‐antigen‐specific B cell responses (LB353). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.lb353] [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: 11/11/2022]
Affiliation(s)
- Hee Kang
- East‐West Medical Science KyungHee UniversityYonginRepublic of Korea
| | - JinSeok Moon
- Chungbuk National University ChongjuRepublic of Korea
| | - NamSoo Han
- Chungbuk National University ChongjuRepublic of Korea
| |
Collapse
|
8
|
Ahn JE, Kim JK, Lee HR, Eom HJ, Han NS. Isolation and Characterization of a Bacteriocin-Producing Lactobacillus sakei B16 from Kimchi. ACTA ACUST UNITED AC 2012. [DOI: 10.3746/jkfn.2012.41.5.721] [Citation(s) in RCA: 8] [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]
|
9
|
Lee WH, Han NS, Park YC, Seo JH. Modulation of guanosine 5'-diphosphate-D-mannose metabolism in recombinant Escherichia coli for production of guanosine 5'-diphosphate-L-fucose. Bioresour Technol 2009; 100:6143-6148. [PMID: 19692232 DOI: 10.1016/j.biortech.2009.07.035] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 07/10/2009] [Accepted: 07/16/2009] [Indexed: 05/28/2023]
Abstract
Guanosine 5'-diphosphate (GDP)-L-fucose, an activated form of a nucleotide sugar, plays an important role in a wide range of biological functions. In this study, the enhancement of GDP-L-fucose production was attempted by supplementation of mannose, which is a potentially better carbon source to be converted into GDP-L-fucose than glucose, and combinatorial overexpression of the genes involved in the biosynthesis of GDP-D-mannose, a precursor of GDP-L-fucose. Supply of a mannose and glucose led to a 1.3-fold-increase in GDP-L-fucose concentration (52.5+/-0.8 mg l(-1)) in a fed-batch fermentation of recombinant E. coli BL21star(DE3) overexpressing the gmd and wcaG genes, compared with the case using glucose as a sole carbon source. A maximum GDP-L-fucose concentration of 170.3+/-2.3 mg l(-1), corresponding to a 4.4-fold enhancement compared with the control strain overexpressing gmd and wcaG genes only, was achieved in a glucose-limited fed-batch fermentation of a recombinant E. coli BL21star(DE3) strain overexpressing manB, manC, gmd and wcaG genes. Further improvement of GDP-L-fucose production was not obtained by additional overexpression of the manA gene.
Collapse
Affiliation(s)
- Won-Heong Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea
| | | | | | | |
Collapse
|
10
|
Kang H, Oh YJ, Ahn KS, Eom HJ, Han N, Kim YB, Sohn NW. Leuconostoc citreumHJ-P4 (KACC 91035) regulates immunoglobulin E in an ovalbumin-induced allergy model and induces interleukin-12 through nuclear factor-kappa B and p38/c-Jun N-terminal kinases signaling in macrophages. Microbiol Immunol 2009; 53:331-9. [DOI: 10.1111/j.1348-0421.2009.00131.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
11
|
Ryu HS, Kim HK, Choi WC, Kim MH, Park SY, Han NS, Oh TK, Lee JK. New cold-adapted lipase from Photobacterium lipolyticum sp. nov. that is closely related to filamentous fungal lipases. Appl Microbiol Biotechnol 2006; 70:321-6. [PMID: 16088345 DOI: 10.1007/s00253-005-0058-y] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 06/02/2005] [Accepted: 06/09/2005] [Indexed: 12/01/2022]
Abstract
A Photobacterium strain, M37, showing lipolytic activity, was previously isolated from an intertidal flat of the Yellow Sea in Korea and identified as Photobacterium lipolyticum sp. nov. In the present study, the corresponding gene was cloned using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (1,023 bp) corresponded to a protein of 340 amino acid residues with a molecular weight of 38,026. No sequence similarity was found with any known bacterial lipases/esterases; instead, the most similar enzymes were several filamentous fungal lipases. Although the similarity was very low (less than 16%), there were many conserved regions over the entire sequence and N-terminal oxyanion hole (RG) region, a signature sequence of filamentous fungal lipases. The novel protein M37 was produced in both a soluble and insoluble form when the Escherichia coli cells harboring the gene were cultured at 18 degrees C. The soluble protein exhibited lipase activity in a pH-stat assay using an olive oil emulsion. The M37 lipase also displayed a maximum activity at 25 degrees C and maintained its activity at a low temperature range (5-25 degrees C) with an activation energy (E(a)) of 2.07 kcal/mol. Accordingly, these results indicate that the M37 lipase from P. lipolyticum sp. nov. is a new cold-adapted enzyme.
Collapse
Affiliation(s)
- H S Ryu
- Korea Research Institute of Bioscience & Biotechnology, P.O. Box 115, Taejon, 305-600, South Korea
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
Expression with a fusion partner is now a popular scheme to produce a protein of interest because it provides a generic tool for expression and purification. In our previous study, a strong polycationic tail has been harnessed for an efficient purification scheme. Here, the same polycation tail attached to a protein of interest is shown to hold versatility for a solid-phase refolding method that utilizes a charged adsorbent as a supporting material. Cyclodextrin glycosyltransferase (CGTase) fused with 10 lysine residues at the C-terminus (CGTK10ase) retains the ability to bind to a cation exchanger even in a urea-denatured state. When the denatured and adsorbed CGTK10ase is induced to refold, the bound CGTK10ase aggregates little even at a g/L range. The renatured CGTK10ase can also be simply recovered from the solid support by adding high concentration of NaCl. The CGTK10ase refolded on a solid support retains specific enzyme activity virtually identical to that of the native CGTK10ase. Several factors that are important in improving the refolding efficiency are explored. Experimental results indicate that nonspecific electrostatic interactions between the charge of the ion exchanger and the local charge of CGTase other than the polycationic tag should be reduced to obtain higher refolding yield. The solid-phase refolding method utilizing a strong polycationic tag resulted in a remarkable increase in the refolding performance. Taken together with the previous report in which a series of polycations were explored for efficient purification, expression of a target protein fused with a strong polycation provides a straightforward protein preparation scheme.
Collapse
Affiliation(s)
- Dae-Hyuk Kweon
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea
| | | | | | | |
Collapse
|
13
|
Kweon DH, Lee DH, Han NS, Rha CS, Seo JH. Characterization of polycationic amino acids fusion systems for ion-exchange purification of cyclodextrin glycosyltransferase from recombinant Escherichia coli. Biotechnol Prog 2002; 18:303-8. [PMID: 11934300 DOI: 10.1021/bp010151l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fusion proteins with charged polycationic amino acid tails were constructed for the purpose of simple ion-exchange purification with high purity. A number of positively charged lysine and arginine tails were fused to the C-terminus of cyclodextrin glycosyltransferase (CGTase) derived from Bacillus macerans and expressed in Escherichia coli. The ionic binding forces provided by the tails allowed the selective recovery of CGTase from recombinant E. coli cell extracts, while CGTase by itself could not bind to the cation exchanger at neutral pH. The type of amino acids used and the length of the tail directly affected the purification factors. Most intracellular proteins of E. coli adsorbed on the cation exchanger could be removed by washing with 400 mM NaCl solution at pH 7.4, suggesting that a fusion partner suitable for purification purpose should be provided with high binding strength and the maintenance of adsorption by washing with NaCl solution. Among the fusion CGTases constructed, the CGTK10ase containing 10 lysine residues provided sufficiently high binding strength to allow purification to its homogeneity through simple ion-exchange chromatography.
Collapse
Affiliation(s)
- Dae-Hyuk Kweon
- School of Agricultural Biotechnology, Seoul National University, Suwon 441-744, Korea
| | | | | | | | | |
Collapse
|
14
|
|
15
|
Park KH, Kim MJ, Lee HS, Han NS, Kim D, Robyt JF. Transglycosylation reactions of Bacillus stearothermophilus maltogenic amylase with acarbose and various acceptors. Carbohydr Res 1998; 313:235-46. [PMID: 10209866 DOI: 10.1016/s0008-6215(98)00276-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
It was observed that Bacillus stearothermophilus maltogenic amylase cleaved the first glycosidic bond of acarbose to produce glucose and a pseudotrisaccharide (PTS) that was transferred to C-6 of the glucose to give an alpha-(1-->6) glycosidic linkage and the formation of isoacarbose. The addition of a number of different carbohydrates to the digest gave transfer products in which PTS was primarily attached alpha-(1-->6) to D-glucose, D-mannose, D-galactose, and methyl alpha-D-glucopyranoside. With D-fructopyranose and D-xylopyranose, PTS was linked alpha-(1-->5) and alpha-(1-->4), respectively. PTS was primarily transferred to C-6 of the nonreducing residue of maltose, cellobiose, lactose, and gentiobiose. Lesser amounts of alpha-(1-->3) and/or alpha-(1-->4) transfer products were also observed for these carbohydrate acceptors. The major transfer product to sucrose gave PTS linked alpha-(1-->4) to the glucose residue. alpha,alpha-Trehalose gave two major products with PTS linked alpha-(1-->6) and alpha-(1-->4). Maltitol gave two major products with PTS linked alpha-(1-->6) and alpha-(1-->4) to the glucopyranose residue. Raffinose gave two major products with PTS linked alpha-(1-->6) and alpha-(1-->4) to the D-galactopyranose residue. Maltotriose gave two major products with PTS linked alpha-(1-->6) and alpha-(1-->4) to the nonreducing end glucopyranose residue. Xylitol gave PTS linked alpha-(1-->5) as the major product and D-glucitol gave PTS linked alpha-(1-->6) as the only product. The structures of the transfer products were determined using thin-layer chromatography, high-performance ion chromatography, enzyme hydrolysis, methylation analysis and 13C NMR spectroscopy. The best acceptor was gentiobiose, followed closely by maltose and cellobiose, and the weakest acceptor was D-glucitol.
Collapse
Affiliation(s)
- K H Park
- Department of Food Science and Technology and Research Center for New Bio-Materials in Agriculture, Seoul National University, Suwon, South Korea.
| | | | | | | | | | | |
Collapse
|
16
|
Song SB, Lee SR, Chung HH, Han NS. [Infection status of anisakid larvae in anchovies purchased from local fishery market near southern and eastern sea in Korea]. Korean J Parasitol 1995; 33:95-9. [PMID: 7551809 DOI: 10.3347/kjp.1995.33.2.95] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A survey was carried out on the larval anisakis in anchovies (Engrauris japonica) which were caught from April to June in 1993 at the southern and eastern sea in Korea. Anisakids in anchovies were morphological classified into Anisakis type I and II and Contracaecum type B and C, after fixation in 70% alcohol and clearing in lactophenol. A total of 171 larval anisakids were collected from 150 anchovies (6.9%) out of 2,180 examined. The infection rates showed no relation with length of the anchovies. The numbers of anisakids by organs of anchovies were 96 (56.1%) from the muscle, 65 (38.0%) from the omentum, 7 (4.1%) from the intestine, 2 (1.7%) from the stomach and 1 (0.6%) from the testis. Infection rates of anchovies with anisakids by localities were 5.1% at Taebyon, 8.0% at Sokcho and 9.2% at Chungmu. The larval anisakids in anchovies may infect humans who often eat raw anchovies.
Collapse
Affiliation(s)
- S B Song
- Department of Parasitology, College of Medicine, Pusan National University, Korea
| | | | | | | |
Collapse
|