• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.671-677
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• 1995

An extracellular enzyme showing lytic activity on E. coli peptidoglycan had been isolated from Bacillus sp. BL-29. The lytic enzyme was purified to homogeneity by ion-exchange chromatography and gel filtration, with a recovery of 5%. The enzyme was monomeric and had an estimated molecular weight of 31,000 Da. The mode of action of the purified enzyme was also investigated. When the purified lytic enzyme was incubated with cell wall peptidoglycan, N-terminal amino groups were released without the release of reducing groups. The N-terminal amino acid released was identified as dinitrophenylalanine (DNP-alanine) by analysis of terminal amino acid by dinitrophenylation method. This result suggests that the lytic enzyme should be a kind of N-acetylmura-myl-L-alanine amidase.

• BMB Reports
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• v.39 no.5
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• pp.511-515
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• 2006

Alanine aminotransferase (AAT) is mainly synthesized in the liver, and its level in mammalian serum is elevated after acute phase induction. Here we demonstrated that sheep anti-human AAT antibody cross-reacted with amphioxus humoral fluids as well as human serum; and the concentration of AAT in the humoral fluids in amphioxus increased after the acute challenge with lipopolysaccharide, while the level of total proteins remains unchanged. These suggest the presence of the same acute phase response pattern in amphioxus, as observed in some mammalian species. Immunohistochemically, AAT was localized in the hepatic diverticulum, ovary and testis. It appears that the hepatic diverticulum in amphioxus is functionally homologous to the vertebrate liver in respect of AAT synthesis, supporting the hypothesis that the vertebrate liver evolved from the hepatic diverticulum of an amphioxus-like ancestor during early chordate evolution.

• The Korean Journal of Zoology
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• v.3 no.2
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• pp.5-8
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• 1960

Paper partition chromatography has been applied to estimate the amino acids in the liver of Bombina orientalis Boulenger. The results obtained are as follows : 1) The presence of cystine, serine, glycine, threonine, alanine, $\beta$-alanine, tyrosine, histidine, asparagine, tryptophane, methionine, valine, phenylalanine, leucine and an unknown substance has been demonstrated in the alcoholic extracts of the material. 2) The presence of glutamine, cystine, serine , glycine, arginine, threonine, histidine, alanine, methionine, proline, valine ,phenylalanine, leucine, and two unknown substances has been demonstrated in the acid-hydrolyzed liver. 3) Tyrosine, asparagine, and trypotphane have been demonstrated only in the alcoholic extract. 4) Proline, glutamine and arginine have been demonstrated only in the acid-jydrolyzed liver.

• Advances in Traditional Medicine
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• v.3 no.1
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• pp.18-20
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• 2003

The purpose of this study was to examine the effect of supplementary highly purified chitosan (HPC) on blood alcohol concentration in healthy human. The human study was performed with two sections. Each section of the study was conducted by two-phase cross-over design with a week wash-out period. All volunteers took HPC in one phase, and took a placebo in the next phase. Blood alcohol concentrations were different between in those taking HPC and in those taking the placebo in the human. And the concentration of serum aspartate aminotransferase (AST, GOT) and alanine aminotransferase (ALT, GPT), the indicator of liver cell damage, was lowered in those taking HPC, compared to those taking the placebo. In conclusion, taking HPC prior to drinking alcohol can somewhat reduce alcohol concentration in human blood and liver cell damage.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.989-992
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• 2005

Dynamic kinetic resolution of $\alpha$-bromo carboxylic acid derivatives in nucleophilic substitution with chiral $\alpha$-amino ester nucleophiles in the presence of TBAI and DIEA has been investigated for stereoselective syntheses of 1,1'-iminodicarboxylic acid derivatives. Nucleophilic substitutions with various chiral $\alpha$-amino esters gave iminodiacetates 2-8 with stereoselectivities up to 87 : 13 dr. Also, the reactions of N-($\alpha$-bromo-$\alpha$-phenylacetyl)-L-alanine methyl ester with L-alanine, D-alanine and glycine methyl ester nucleophiles afforded N-carboxyalkyl dipeptide analogues 10-12 up to 90 : 10 dr.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.15-17
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• 1961

A ninhydrin positive substance(formed during germination of Mung Bean) which on a 2-dimensional chromatography(BuOH-HAc, and$ PhOH-NH_2$ gave a spot above glutamic acid was isolated by cutting out the appropriate spot on the paper and extracting the paper with water. Hydrolysis of this substance with $2N H_2SO_4\;or\;3N\;HCl\;at\;120^{\circ}C$ for 15 hours gave the spot of mainly glutamic acid, alanine and very faint of glycine and cysteine on a paper chromatography. It is suggested that the reaction of ${\gamma}$-glutamyl-cysteinecyl-glycine + L-alanine in the presence of ${\gamma}$-glutamyle transferase ${\rightarrow}$ ${\gamma}$-glutamyl-alanine + cysteinyl-glycine, takes place in germinated Mung Bean.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.2
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• pp.87-91
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• 2010

Silk fibroin model peptide, alanine pentamer was synthesized through solid-phase method and modified with poly(ethylene glycol). Nuclear magnetic resonance spectrometry and Fourier-transform infrared spectroscopy showed the conformation of alanine pentamer, $\beta$-sheet structure and random coil conformation were not changed with PEGylation. Differential scanning calorimetry showed that relatively strong exothermic peak around $180^{\circ}C$ by PEGylation. No cytotoxicity of PEGylated pentamer was observed by L929 cell proliferation test.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.425-430
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• 2022

L-alanine (LA, as an amino acid residue) pentamer model was used to investigate changes in the dihedral angle, intramolecular hydrogen bonding and formation energies during structural optimization. LA pentamers having four conformation types [𝛽: 𝜑/𝜓=t-/t+, 𝛼: 𝜑/𝜓=g-/g-, PP_II: 𝜑/𝜓=g-/t+ and P-like: 𝜑/𝜓= g-/g+] were carried out by quantum chemical calculations (QCC) [B3LYP/6-31G(d,p)]. In LA, 𝛽, 𝛼, and P-like types did not change by optimization, having an intra-molecular hydrogen bond: NH⋯OC (H-bond), and PP_II types in the absence of H-bond were transformed into P-like at the designated 𝜓 of 140°, and to 𝛽 at that of 160° or 175°. P-like and 𝛼 were about 0.5 kcal/mol/mu more stable than 𝛽. In order to understand the processes of the transformations, the changes of 𝜑/𝜓, distances of NH-OC (d_NH/CO) and formation energies (𝜟E, kcal/mol/mu) were examined.

• Analytical Science and Technology
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• v.7 no.1
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• pp.53-64
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• 1994

After establishment of methodology for the separation and quantitation of optical isomer existed in food or biomaterial, the relationship between isomer and nutrient or biological sample was investigated. The optical isomers of standard amino acids and free amino acids were quantitized and the protein was assayed from the Korean bean, pasted bean, soy sauce, gochujang, powderd milk and cataract followed by hydrolysis and dervatization with TFA-IPA for GLC analysis with chirasil val column. Amino acids showing the racemization were alanine, aspartic acid, glutamic acid and phenyl alanine. The most convenient amino acid deducing age and biological activity was aspartic acid. Glutamic acid and phenyl alanine have shown poor resolution with less racemization. The ratio of d-form amino acids was 3~6% for home made pasted bean, about 3% for commerical pasted bean, 2~4% for soy sauce, about 1% for bean, 1~2% for cataract, 1.0~1.5% for powdered milk. The racemization during fermentation process was significant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.27-31
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• 1980

Yellow sea bream, Branchiostegus japonicus, has been one of the widely consumed food fish in Jeju-Do, Korea. This study was attempted to establish the basic data for evaluating changes of taste compounds of the yellow sea bream during dehydration. The free amino acids were analysed by amino acid autoanalyser. The free amino acid composition of the raw yellow sea bream, abundant amino acids were lysine, alanine, threonine and arginine and then taurine, serine, proline, glycine, glutamic acid, leucine in order. Such amino acids as valine, methionine, tyrosine, isoleucine, phenylalanine were poor in content. The changes of free anino acid composition in the extract of the yellow sea bream during dehydration was not found. In the extract of dried product, lysine, alanine, glutamic acid and arginine were dominant holding $18.4\%,\;14.7\%\;8.0\%\;and\;7.3\%$ and $7.3\%$ of total amino acids respectively. The amount of total free amino acids of the yellow sea bream increased to more than 1.4 times during dehydration process, that of raw sample especially aspartic and glutamic acids increased to more than 2.9 times and 2. 1 times whereas taurine and histidine decreased ranging $40-50\%$ of the original content. It is presumed that the characteristic flavor of dried yellow sea bream was attributed to such amino acids like lysine and alanine known as sweet compounds, glutamic acid as meaty taste and TMAO known as plain sweet taste.