• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1389-1396
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• 2014

The entire nucleotide sequence of the TKL1 gene encoding transketolase (TKL) in an erythritol-producing yeast of Candida magnoliae was determined by degenerate polymerase chain reaction and genome walking. Sequence analysis revealed an open reading frame of C. magnoliae TKL1 (CmTKL1) that spans 2,088 bp and encodes 696 amino acids, sharing 61.7% amino acid identity to Kluyveromyces lactis TKL. Functional analysis showed that CmTKL1 complemented a Saccharomyces cerevisiae tkl1 tkl2 double mutant for growth in the absence of aromatic amino acids and restored transketolase activity in this mutant. An enzyme activity assay and RT-PCR revealed that the expression of CmTKL1 is induced by fructose, $H_2O_2$, and KCl. The GenBank accession number for C. magnoliae TKL1 is KF751756.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.248.2-248.2
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• 2000

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.668-676
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• 2001

Pseudomonas sp. strain SY5 is a PCB-degrading bacterium [24] that includes two different enzymes (BphC1 and BphC2) encoding 2,3-dihdroxybiphenyl 1,2-dioxygenase and BphD encoding 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase. The bphC1 and bphC2 genes were found to consist of 897 based encoding 299 amino acids and 882 bases encoding 294 amino acids, respectively, whereas the bphD gene consisted of 861 bases encoding 287 amino acids. According to a homology search, a 50% and 39% similarity between the bphC1 and bphC2 genes at the nucleotide and amino acid level was shown, respectively. The bphC1 gene showed a 38% and 45% similarity at the amino acid level to Alcaligenes eutrophus A5 and Rhodococcus rhodochrous, respectively, whereas, bphC2 showed a 95% and 43% similarity, respectively. A comparison of the deduced amino acid sequence of the bphD product of Pseudomonas sp. SY5 with that of A. eutrophus A5, Pseudomons sp. KKS102, and LB400 showed a sequence identity of 92, 92, and 79%, respectively. Strain SY5 was originally isolated from municipal sewage containing recalcitrant organic compounds an found to have a high degradability of various aromatic compounds [23]. The current study found that strain SY5 had two extradiol-type dioxygenases, which did not hybridize with each other as they had a low similarity, yet a similar structure of evolutionarily conserved amino acids residues for catalytic activity between BphC1 and BphC2 was observed.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.964-971
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• 1995

Volatile flavor compounds and free amino acids in untreated and hydrolysate pen shell by-product produced with APL 440 protease were compared by vacuum simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. A total of 109 volatile flavor compounds were detected in hydrolysate (65 compounds) or the 109 volatile flavor compounds were detected in untreated pen shell by-product (88). These compounds were composed of aldehydes(16), ketones(17), alcohols(31), nitrogen containing compounds (16), aromatic hydrocarbon compounds(8), esters(3), and miscellaneous compounds (17). Levels of aldehydes and aromatic hydrocarbons decreased after hydrolysis, whereas levels of nitrogen containing compounds increased 3 times than in untreated pen shell by-product. Taurine, known to be having a physiological function, was accounted for 31.25% of total amino acids in hydrolysate.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.247-251
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• 1997

Effects of amino acids on the lactic acid bacteria in kimchi were studied. 73 different lactic acid bacteria have been isolated during the kimchi fermentation at $15^{\circ}C$. Among these bacteria, dextran formers were occupied by 69.9%, of which Leuconostoc and Lactobacillus were 4.1% and 65.8%, respectively. All isolates didn't grow in a medium added with 500 ppm of tyrosine, whereas such an inhibition was not exhibited in kimchi with the same concentration of tyrosine. In kimchi added with tyrosine the lactic acid bacteria were less diverse than in the natural kimchi but the ratio of dextran formers were similar. As contrasted with natural kimchi, Leuconostoc was rather increased up to 41.4% and Lactobacillus was decreased down to 29.3%. Dominant species in each genus were Leu. mesenteroides and Lac. minor. Thus it is believed that tyrosine had inhibition effect for the growth of most Lactobacillus in kimchi.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.306-315
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• 2009

Due to the depleting petroleum reserve, recurring energy crisis, and global warming, it is necessary to study the development of white biotech-based aromatic chemical feedstock from renewable biomass for replacing petroleum-based one. In particular, the production of aromatic intermediates and derivatives in biosynthetic pathway of aromatic amino acids from glucose might be replaced by the production of petrochemical-based aromatic chemical feedstock including benzene-derived aromatic compounds. In this review, I briefly described the production technology for hydroquinone, catechol, adipic acid, shikimic acid, gallic acid, pyrogallol, vanillin, p-hydroxycinnamic acid, p-hydroxystyrene, p-hydroxybenzoic acid, indigo, and indole 3-acetic acid using metabolic engineering, bioconversion, and chemical process. The problems and possible solutions regarding development of production technology for competitive white biotech-based aromatic compounds were also discussed.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.129-135
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• 1976

The amino acid compositions of polished barley grain were investigated for 16 varieties by using amino acid autoanalyzer and simple correlation analysis between them and between protein and amino acid per protein was done. 1) Limiting amino acid is lysine, leucine and phenylalanine are high but threonine and tyrosine are low. Total essential amino acids is high. 2) Protein is significantly correlated negatively with lysine arginine, total basic amino acids (at p=0.01) and threonine, alanine, aspartic acid (at p=0.05) and positively with phenylalanine (at p=0.01) proline and cystine (at p=0.05). 3) Lysine is positively and significantly correlated with arginine and aspartic acid indicating that aspartic acid is probable precursor of lysine and that high yielding varieties or fertilization for high yielding decrease aspartic acid pool resulting low lysine. 4) Lysine content is positively correlated with dye binding capacity (at p=0.01). 5) Tryptophan is positively (at p=0.01) and significantly correlated with histidine, total basic amino acids and arginine. 6) In essential amino acids lysine, tryptophan, threonine and valine simultaneously increase or decrease while aromatic amino acids, sulfur contained amino acids, isoleucine and leucine do so together.

• Analytical Science and Technology
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• v.25 no.3
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• pp.171-177
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• 2012

A determination method of aromatic amino acids such as trytophan (Trp), tyrosine (Tyr), and phenylalanine (Phe) using luminol-$H_2O_2$-Cu(II) system has been presented. In the presence of an aromatic amino acid, the enhanced chemiluminescence (CL) intensity of luminol-$H_2O_2$-Cu(II) system was obtained by forming a complex between Cu(II) and the amino acid. Based on the above phenomenon, a sensitive and fast determination of three aromatic amino acids was performed using the CL method in batch-type detection system. To optimize determination conditions, the kinetic influence of an aromatic amino acid on the luminol-$H_2O_2$-Cu(II) system and the effects of $H_2O_2$ and Cu(II) concentration, pH, and buffers were investigated. Under the optimized conditions, the calibration curve was linear over the range from $1.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Trp, $1.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Try, and $2.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Phe, respectively. In this range, reproducibility (RSD, n = 4) of Trp, Try, and Phe were 3.21%, 2.64%, and 2.48%, respectively. The limit of detection ($3{\sigma}/s$) was calculated to be $6.8{\times}10^{-7}\;M$ for Trp, $5.7{\times}10^{-7}\;M$ for Try, and $9.6{\times}10^{-7}\;M$ for Phe.

• Journal of Animal Science and Technology
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• v.63 no.5
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• pp.1169-1181
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• 2021

We investigated the comparative physicochemical attributes, oxidative stability, and microbial characteristics of 28 days dry-aged meat in between boneless sirloin (gluteus medius) and bone-in T-bone steaks (infraspinatus) muscles from Korean Native Hanwoo Steer (KNHS). Results reveal that regardless of the muscles, dry-aging increased protein content and water-holding capacity (WHC) (p < 0.05). Meat from infraspinatus-aged muscle led to darker meat with higher pH values than un-aged meat (p < 0.05). However, fat content, CIE a^*, and CIE b^* remained unchanged in both muscles at aging. At aged meat, thiobarbituric acid reactive substances (TBARS) values from bone-in infraspinatus muscle was 2.5-fold higher than boneless gluteus medius muscle (p < 0.05). Dry-aging led to an increase in the contents of total unsaturated fatty acids (UFAs), monounsaturated fatty acids (MUFAs), and UFA/saturated fatty acids (SFA) in both muscles (p < 0.05). Furthermore, gluteus medius aged muscle concentrated with olic acid (C18:1) compared to infraspinatus aged muscle. Irrespective of the muscles, dry-aging enhanced the total free amino acids (FAAs) as well as tasty, and bitter amino acid contents whereas decreased the tasty/bitter amino acids (p < 0.05). Aromatic amino acid, tryptophan that converted to serotonin was 2-fold higher in boneless gluteus medius muscle than bone-in infraspinatus muscle at pre and post aging processes (p < 0.05). Aged Infraspinatus muscle increased total bacteria (p < 0.05) while no salmonella spp. was detected in both muscles. Taken together, our study confirms that 28 days dry-aging profiling the quality characteristics of boneless sirloin (gluteus medius) and bone-in T-bone steaks (infraspinatus) distinctly while gluteus medius aged steak performs better owing to oxidative stability and functional compounds than infraspinatus aged steak.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.29-30
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• 2006

The synthesis of dendritic dipeptides $(4-3,4-3,5)12G2-CH_{2}-Boc-_{L}-Tyr-X-OMe\;where\;X\;=\;Gly,\;_{L}-Val,\;_{L}-Leu,\;_{L}-Ile,\;_{L}-Phe$, and L-Pro will be discussed. Their self-assembly in bulk and in solution and the structural and retrostructural analysis of their periodic assemblies will be compared to that of the previously reported and currently reinvestigated dendritic dipeptide with $X=_{L}-Ala$. All dendritic dipeptides containing as X nonpolar ${\alpha}-amino$ acids self-assemble into helical porous columns. The principles via which the aliphatic and aromatic substituents of X program the structure of the helical pores indicate synthetic pathways to helical pores with bioinspired functions based on artificial nonpolar ${\alpha}-amino$ acids will be discussed.