• Journal of Microbiology and Biotechnology
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• v.5 no.2
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• pp.68-73
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• 1995

Pseudomonas sp. P20 was shown to be capable of degrading biphenyl and 4-chlorobiphenyl (4CB) to produce the corresponding benzoic acids wnich were not further degraded. But the potential of the strain for biodegradation of 4CB was shown to be excellent. The pcbA, B, C and D genes responsible for the aromatic ring-cleavage of biphenyl and 4CB degradation were cloned from the chromosomal DNA of the strain. In this study, the pebC and D genes specifying degradation of 2, 3-dihydroxybiphenyl (2, 3-DHBP) produced from biphenyl by the pebAB-encoded enzymes were cloned by using pBluescript SK(＋) as a vector. From the pCK102 (9.3 kb) containing pebC and D genes, pCK1022 inserted with a EcoRI-HindIII DNA fragment (4.1 kb) carrying pebC and D and a pCK1092 inserted with EcoRI-XbaI fragment (1.95 kb) carrying pebC were constructed. The expression of pcbC and D' in E. coli CK102 and pebC in E. coli CK1092 was examined by gas chromatography and UV-vis spectrophotometry. 2.3-dihydroxybiphenyl was readily degraded to produce meta-cleavage product (MCP) by E. coli CK102 after incubation for 10 min, and then only benzoic acid(BA) was detected in the 24-h old culture. The MCP was detected in E. coli CK1022 containing pebC and 0 genes (by the resting cells assay) for up to 3 h after incubation and then diminished completely in 8 h, whereas the MCP accumulated in the E. coli CK1092 culture even after 6 h of incubation. The 2, 3-DHBP dioxygenases (product of pebC gene) produced by E. coli CK1, CK102, CK1023, and CK1092 strains were measured by native PAGE analysis to be about 250 kDa in molecular weight, which were about same as those of Pseudomonas sp. DJ-12, P. pseudoa1caligenes KF707, and P. putida OU83.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.155-161
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• 2001

A bactriocin produced by Lactrococcus sp. HY449 was purified by sequential purfication steps such as n-propanol-acetone precipitation ion -exchange chromatography using CM-Sequential CL6B. gel filtration chromatography using Sephacry HR100 and reverse-phase chromatography using pro RPC HR 5/10. Reverse-phase chromatography the final step of the purfication yielded a single symmetrical peak of bacteriocin activity The purification resulted in final yield of 3.25% and 413.35 fold increase of the specific activity of bacteriocin. The active fraction from reverse-phase chromatography was used for N-terminal amino acid analysis . The purified bacteriocin contained isoleucine, leucine, methionine, and glycine at but N-terminal end no aromatic amino acids. Calculation of the number of amino acid residues in the bacteriocin revealed that it is consisted of 32 residues assuming the molecular weight of bacteriocin to be about 3.6kDa. Edman degrandation elucidated amino acid residues of the first four of the N-terminus to be $NH_2$-Ile-Leu-Pro-GIn.

• KSBB Journal
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• v.16 no.6
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• pp.562-567
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• 2001

Aspergillus niger LK harboring the enantioselective epoxide hydrolase (EHase) activity was isolated, and enantioselectivity of EHase was tested for various racemic aromatic epoxides. The gene encoding epoxide hydrolase was cloned from cDNA library generated by reverse transcriptase-polymerase chain reaction of the isolated total mRNA. Sequence analysis showed that the cloned gene encodes 398 amino acids with a deduced molecular mass of 44.5 kDa. Database comparison of the amino acid sequence reveals that it is similar to fungal EHase, whereas the sequence identity with bacterial EHase is very low. Recombinant expression of the cloned EHase in Escherichia coli BL21 yielded an active EHases, which can offer a potential biocatalyst for the production of chiral epoxides.

• Analytical Science and Technology
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• v.17 no.2
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• pp.163-172
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• 2004

The molecular size distribution and fluorescence properties of soil fulvic acids (FA) were characterized by using gel filtration chromatography (GFC) and luminescence spectroscopy. The objectives of this work were to fractionate the FA extracted from a forest soil into different nominal molecular size using GFC system and to characterize the fluorescence properties (excitation, emission and synchronous) of these fractions using luminescence spectrometer. The GFC column was calibrated with polyethylene glycols, acetone and dextrane Blue. The total permeation volume of the GFC system was 404 mL and the void volume 130 mL. The GFC molecular weight of the soil FA was in the range of 190~8,900 Dalton and the molecular weight at the peak on the chromatogram was 930 Dalton. The fluorescence intensity ratio ($I_{498nm}/I_{390nm}$) was found to be increased with an increasing molecular weight. This results may suggest that the fulvic acid fractions with high molecular weight have large amount of the condensed aromatic compound.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.470-475
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• 2006

In order to elucidate the differences of protein profiles among soybean cultivars, the protein composition of three conventional domestic soybean cultivars and two imported ones including glyphosate-tolerant HS2906 was analyzed by total nitrogen measurement, amino acid analysis and PAGE/densitometry. There were no statistically significant differences in the levels of any amino acid, including aromatic amino acids, between glyphosale-tolerant soybean and the conventional soybean WS82. In the extraction of protein, the SDS/buffer system was more efficient than the defatting/water system. The SDS-PAGE/densitometry analysis showed that there was a similar profile of proteins among cultivars, although the amount of total protein ranged from 380.2 mg/g to 423.9 mg/g. In addition, there was no discernable difference of protein profile between glyphosate- tolerant soybean (total protein amount, 380.2 mg/g) and the conventional soybean WS82 (390.2 mg/g), although the amount of ${\beta}$-conglycinin (55 kDa) was lower in glyphosate-tolerant soybean. Meanwhile, the amount of 25 kDa protein was greater in domestic soybean cultivars than imported ones. Thus, normal PAGE/ densitometry method would be useful to analyze the difference in protein profiles of soybean proteins, and furthermore Evaluate the protein profile of proteins between GMO and conventional soybean.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.548-552
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• 2005

Volatile fragrance components in 5 kinds of Korean native Lilium were investigated and compared. The volatile components were extracted by SDE (simultaneous steam distillation and extraction) and identified by CC and GC-MS. As a result of the analysis of volatile aromatic ingredient of L. leichtlinii var. tigrinum Nickels., L. concolor var. parthneion Bak., L. tsingtauense Gilg., L. hansonii Leichtl., and L. amabile Palibin., using frozen materials, 60 kinds of volatile compound were identified, which were 28 aldehydes, 9 ketones, 8 alcohols, 5 esters, 5 acids, 3 furans and 2 others. The GC patterns of the aroma components of all samples resembled but the peak areas were different according to species, though all of them are Korean native Liliums.

• Food Science and Preservation
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• v.30 no.2
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• pp.287-299
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• 2023

In vitro luwak coffee was produced using enzyme­microbial complexes. The coffee quality of non-fermented coffee beans (NFC) and fermented coffee beans (FC) was compared. The total free amino acid content was higher in FC than in NFC. The levels of glutamic acid and γ-amino-n-butyric acid in NFC were higher than those in FC; however, the contents of essential amino acids, such as lysine, leucine, and valine, in FC were higher than in NFC. During fermentation, the sucrose content decreased, whereas the fructose and glucose contents increased (p<0.001). The chromaticity of the coffee extract showed higher lightness (L), redness (a), and yellowness (b) values in FC than those in NFC. The caffeine content was significantly lower in FC (696.94±0.04 ㎍/mL) compared to that in NFC (1,130.22±1.55 ㎍/mL) (p<0.001). Conversely, the polyphenol and chlorogenic acid contents were significantly higher in NFC than in FC (p<0.001). Electronic nose analysis indicated considerable differences between the volatile aromatic components in NFC and FC. Sensory scores were significantly higher for FC than those for NFC. Therefore, the fermentation of coffee beans using enzyme­microbial complexes altered the chemical components, which promoted the Maillard reaction during the coffee bean roasting process. These results suggest the possibility of producing in vitro luwak coffee with better flavor and lower caffeine content.

• Journal of Life Science
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• v.24 no.11
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• pp.1168-1173
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• 2014

The homogentisate 1,2-dioxygenase (HGD) gene, which consists of 14 exons and spans approximately 42630bp on Bos taurus autosome 1 (BTA 1), is one of the six enzymes required for catabolism of the aromatic amino acids tyrosine and phenylalanine. It has been reported that BTA1 harbors quantitative trait loci that effect marbling score (MS), carcass weight (CW), and longissimus muscle area (LMA) in cattle. The aim of this study was to identify the single nucleotide polymorphisms (SNPs) in the HGD gene and to analyze their association with economic traits in Korean cattle (Hanwoo). Genetic polymorphisms were screened by direct sequencing, which detected 10 SNPs (T11187C, T11301A, T11398G, G29833A, G34256T, G34257C, T34284C, T42333G, T42348C, and T42468C). Six polymorphic sites were selected for genotyping, and economic traits were analyzed using a general linear model in Korean cattle (n=90). The observed genotype frequencies for G34256T were 0.5843(GG), 0.3708(GT), and 0.0449(TT). In addition, 0.3596(GG), 0.3708(GC), and 0.2697(CC) were observed for the G34257C mutation. Statistical association analysis revealed that G34256T polymorphisms were significantly associated with MS, and G34257C polymorphisms were significantly associated with MS and LMA (p<0.05). Further study is needed in order to use the genetic variant as a marker for marker-assisted selection in Korean cattle.

• Journal of Life Science
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• v.20 no.8
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• pp.1193-1200
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• 2010

The cDNA cloning and developmental profiles of the mRNA for A. pernyi arylphorin was determined. The complete A. pernyi arylphorin cDNA sequence comprised 2,234 bp (without the poly $A^+$ tail), including an open reading frame of 2,112 bp beginning with a methionine ATG at bp34. The A. pernyi arylphorin contained 704 amino acids which are highly enriched in aromatic amino acids, phenylalanine and tyrosine. The calculated molecular mass of the A. pernyi arylphorin from the ORF was 83,439 Da. The deduced amino acid sequence of A. pernyi arylphorin showed 78, 71, 62 and 64% identity with those of H. cecropia, M. sexta $\alpha$ subunit, M. sexta $\beta$ subunit and B. mori storage protein. In Northern blot analysis, the A. pernyi arylphorin mRNA only in the fat body of the 5th instar larvae was responsible for gene expression of the protein, and the synthetic activity of the mRNA was detected strongly in the early larvae, but not in the middle or late-stage larvae. In addition, a very weak signal in mRNA activity was detected in pupal stages, but this was considered to be inactive mRNA after reviewing the results of the labeling experiment of this protein.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.648-655
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• 2010

This study is the first comprehensive report on the molecular cloning, structural characterization, sequence comparison between wild and mutant types, copy number in the genome, expression features and activities of a gene encoding 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in Korean lawn grass ($Zoysia$ $japonica$). The full length cDNA of the EPSPS from Korean lawn grass ($zj$EPSPS) obtained from a 3' and 5' RACE method was 1540 bp, containing a 1176 bp ORF, a 144 bp leader sequence (5' UTR) and a 220 bp 3' UTR, which was eventually decoded 391 amino acid residues with a molecular mass of 41.74 kDa. The Southern blot detection of the $zj$EPSPS showed that the gene exists as a single copy in the Korean lawn grass genome. Sequence comparison of the $zj$EPSPS gene demonstrated that the glyphosate-tolerant mutant (GT) having a Pro-53 to Ser substitution in the gene seems to have a preferred binding activity of the enzyme to phosphoenol pyruvate(PEP) over glyphosate, which allows the continuous synthesis of aromatic amino acids in the shikimate pathway. From the Northern blotting analysis, the $zj$EPSPS was found to be highly expressed, with continuous increase until 36 hours after 0.5% glyphosate treatment in both wild and mutant samples, but 1.5-fold higher EPSP synthase activity was observed in the tolerant mutant when exposed to the glyphosate treatment. The molecular information of the $zj$EPSPS gene obtained from this study needs to be further dissected to be more effectively applied to the development of gene-specific DNA markers and zoysiagrass cultivars; nevertheless, the glyphosate-tolerant mutant having the featured $zj$EPSPS gene can be provided to turfgrass managers for weed problems with timely adoptable management options.