• Applied Biological Chemistry
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• v.24 no.2
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• pp.101-104
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• 1981

Changes in free amino acid composition in cotyledon and axis was investigated during growth of soybean sprout. Free amino acid increased with sprout-growth, especially in axis. Arginine, proline and methionine did not appear in axis throughout. Free amino acids in total amino acids was 0.11% for soybean and 8.8% for 8 day-sprout. Free amino acid change in the course of culture was in order of Asp>His>Val>Ile>Thr>Ser>Lys>Tyr>Phe>Leu>Ala>Gly>Pro>Arg>Glu>Met. The content of free amino acid in 4 day-sprout was in order of Asp>Ser>Val>His>Ala>Ile>Lys>Thr>Arg>Leu>Glu>Phe>Tyr>Gly>Cys>Met>Pro.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.524-531
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• 2005

Two experiments were conducted to standardize in ovo injection of amino acids (AA) and to evaluate the effect of in ovo injection of limiting AA(s) on pre and post hatch growth performance, immune response and development of digestive organs. Combinations of essential and non-essential amino acids (Lys+Arg, Lys+Met+Cys, Thr+Gly+Ser, Ile+Leu+Val and Gly+Pro) were injected into 50 eggs in each treatment group at 14 d of embryonic age. Standardization of injection site, needle length and embryonic age revealed that when AA were injected in to the broad end of the egg with a 11 mm needle and at the narrow end with a 24 mm needle both at the 7$^{th}$ and 14$^{th}$ d of incubation there was poor hatchability. However, better hatchability was recorded when the AA were injected in the narrow end of the egg with a 11 mm needle and in the broad end with a 24 mm needle on the 14$^{th}$ d of incubation. The chick to egg weight ratio was higher (p<0.018) when AA were injected on the 14$^{th}$ d of incubation. When a combination of amino acids were injected a 63.6 or 63.2 g difference in body weight of bird at 21 d was recorded between uninjected control and Ile+Leu+Val or Gly+Pro group, respectively. Higher feed intake (p<0.047) was recorded in the AA injected groups and feed conversion ratio (FCR) was numerically better in Gly+Pro, Lys+Met+Cys AA injected groups than in the uninjected control. Significantly higher immune response to cell mediated (p<0.033) and humoral (p<0.002) immunity was observed in in ovo amino acid injected birds, especially in Lys+Met+Cys, Thr+Gly+Ser or Ile+leu+Val groups. The digestive organ weights at 21 d did not differ between specific AA injected groups and the uninjected control. In ovo injected amino acids may act as immunomodulators and their role in gastrointestinal development needs further research.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.83-90
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• 2005

ACE-inhibitory peptides derived from goat's whey hydrolyzed by various proteolytic enzymes were separated and purified for antihypertension materials. The highest ACE-inhibitory activity of goat's whey hydrolysates was 85.5 % by pepsin for 72 hrs. Also the highest ACE-inhibitory activity of goat's whey hydrolysates was F-4 by pepsin for 72 hrs by Sephadex G-25 gel chromatograms. F-4e and F-4ed from F-4 by RP-HPLC to first and second purification were the highest in ACE-inhibitory activity, respectively. The most abundant amino acid was leucine(I 8.54 %) in F-4ed of ACE-inhibitory peptides after second purification. Amino acid sequence of F-4ed of ACE-inhibitory peptides showed Leu-Lys-Asp-Tyr-Gly-GlyVal- Ser-Leu and Leu-Gly-Asp-Gly-Ala-Gly- Asp-Val-Ala-Phe. $IC_{50}$ calibrated in peptic hydrolysates(72 hrs), F-4, F-4e and F-4ed from goat's whey hydrolysates by pepsin for 72 hrs were 33.93, 28.75, 11.74 and 1.09 mg/ml, respectively. From the results of this experiment, goat's whey hydrolysate by pepsin was shown to have ACE-inhibitory activity.

• BMB Reports
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• v.35 no.2
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• pp.228-235
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• 2002

Methionine aminopeptidase (MetAP) catalyzes the removal of an amino-terminal methionine from a newly synthesized polypeptide. The enzyme was purified to homogeneity from Bacillus stearothermophilus (KCTC 1752) by a procedure that involves heat precipitation and four sequential chromatographs (including DEAE-Sepharose ion exchange, hydroxylapatite, Ultrogel AcA 54 gel filtration, and Reactive red 120 dye affinity chromatography). The apparent molecular masses of the enzyme were 81,300 Da and 41,000 Da, as determined by gel filtration chromatography and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively. This indicates that the enzyme is comprised of two identical subunits. The MetAP specifically hydrolyzed the N-terminal residue of Met-Ala-Ser that was used as a substrate, and exhibited a strong preference for Met-Ala-Ser over Leu-Gly-Gly, Leu-Ser-Phe, and Leu-Leu-Tyr. The enzyme has an optimal pH at 8.0, an optimal temperature at $80^{\circ}C$, and pI at 4.1. The enzyme was heat-stable, as its activity remained unaltered when incubated at $80^{\circ}C$ for 45 min. The Km and Vmax values of the enzyme were 3.0mM and 1.7 mmol/min/mg, respectively. The B. stearothernmophilus MetAP was completely inactivated by EDTA and required $Co^{2+}$ ion(s) for activation, suggesting the metal dependence of this enzyme.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.261-265
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• 1993

For the purpose of supplying the information to improve the acceptability of soy paste as the condi-ment, the changes of peptide were determined. The results were as follows; Average peptide length were decreased. It was 102 at 0 day, 15 at 10 day and 4.1 at 180 day. Peptide fraction were the same as in 60 day and 180 day. Low molecular weight peptide were not changed greatly during fermention. Peptide identified in 180 day fermentation were Ala-Ser, Gly-Glu, Glu-Ser, Asp-Glu, Asp- Tyr, Asp-Ala-Ser, Ala-Ser-Glu, Glu-Ser-Ala, and Ala-Lys-Met. In the characteristics of bitter peptide in 180 day fermentation, soy paste itself didn't show bitter taste', solvent extration fraction I'showed bitter taste. After gel chromatography, fraction I, fraction II and fraction III were obtained and fraction II were bitter peptide of low molecular weight. After gel chromatography', solvent extration fraction 2'(water extration) were divided into fraction IV, V, VI,VII and VIII. Fraction IV, V and VI showed bitter taste. Amino acids composition of the fractions showing bitter taste were like that; fr. 1: Glu- (Asp, Pro, Val, lie or Leu)-Met fr. II Pro-(Glu, Val, Phe)-lle or Leu fr. IV: Glu-(Asp, Ala, Tyr, Leu of lie)-Phe fr. V: Ala-(Met, Glu, Pro)-lle or Leu fr. VI: Asp-(Phe, Ser, fly)-Val.

• Applied Biological Chemistry
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• v.9
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• pp.83-90
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• 1968

In order to elucidate the differences among the parts of internal organs of salted fishes (Chang Zut), five parts of the organs were examined for their chemical constituents including amino acids. The moisture content varied from 59.8% to 72.8% Crude protein; 7.13% to 11.19%, Crude ash; to 16.1%, 24.8%, Sodium chloride; 15.3% to 22.4% and ash; 0.8% to 2.2%. Seven essential amino acids including leucine, isoleucine, phenylalanine, tryptophan, threonine, lysine and methionine except valine were existed in the every part of the organ. The contents of tyrosine and hydroxyproline were relatively high, on the other hand, tryptophan was trace amount in the every parts.

• BMB Reports
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• v.31 no.1
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• pp.37-43
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• 1998

The catabolic ${\alpha}$-acetolactate synthase was purified to homogeneity from Serratia marcescens ATCC 25419 using ammonium sulfate fractionation, DEAE-Sepharose, Phenyl-Sepharose, and Hydroxylapatite column chromatography. The native molecular weight of the enzyme was approximately 150 kDa and composed of two identical subunits with molecular weights of 64 kDa each. The N-terminal amino acid sequence of the enzyme was determined to be Ala-Gln-Glu-Lys-Thr-Gly-Asn-Asp-Trp-Gln-His-Gly-Ala-Asp-Leu-Val-Val-Lys-Asn-Leu. It was not inhibited by the branched chain amino acids and sulfometuron methyl herbicide. The optimum pH of the enzyme was around pH 5.5 and the pI value was 6.1. The catabolic ${\alpha}$-acetolactate synthase showed weak immunological relationships with recombinant tobacco ALS, barley ALS, and the valine-sensitive ALS isozyme from Serratia marcescens.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.287-292
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• 1988

The interaction between Lactobacillus acidophilus and Kluyveromyces fragilis on the utilization of amino acids in soymilk was investigated. K. fragilis assimilated relatively well various amino acids such as Met., ILe., Phe., Leu., Thr., Lys., Val., Arg., Tyr., Ser., Asp., Ala. and Glu. that existed only in trace amounts in soymilk. K. fragilis did not utilized Gly., while hi accumulated His. L. acidophilus hydrolyzed soyprotein to liberate various amino acids. Among various amino acids, it utilized Met., ILe., Thr., Tyr., Ser., Val. and His. as growth factors and accumulated Leu., Phe., Lys., Arg., Glu., Asp. and Ala. among the essential amino acids required by K. fragilis and Gly. These results implied that K. fragilis grew on amino acids that existed only in trace amounts in soymilk, but it's growth was stimulated by amino acids such as Leu., Phe., Lys., Arg., Glu., Asp. and Ala. ac-cumulated by L. acidophilus.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.409-414
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• 2009

Novel binol aldehydes derivatized at 2' hydroxy position with both uryl and acetamide groups (2), and diuryl groups (3) have been synthesized. Both were designed for streospecific binding and chirality conversion of general dipeptides with support of multiple hydrogen bonding donor sites in the receptors. The receptors, 2 and 3, converted the chirality of N-terminal amino acids of peptides such as Ala-Gly, Met-Gly, Leu-Gly and His-Gly with stereoselectivity on D-form over L-form. The stereoselectivity ratios were in the range of 5-11, somewhat higher than those of the binol receptor with mono uryl group (1). The DFT calculation at the B3LYP/6-31G$^*$//MPWB1K/6-31G$^*$ level revealed that 3-D-Ala-Gly was 2.2 kcal/mol more stable than 3-L-Ala-Gly. The considerable steric hindrance between the methyl group of the alanine and the imine CH moiety of the receptor seems to be the main contributing factor for the thermodynamic preference.

• BMB Reports
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• v.32 no.3
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• pp.239-246
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• 1999

A tripeptidase (PepT) was purified to homogeneity from Bacillus subtilis through four sequential chromatographies including DEAE-Sepharose ion exchange, hydroxylapatite, mono-Q FPLC ion exchange, and Superose-12 FPLC gel filtration. The apparent molecular mass of the enzyme was 49,200 Da and 51,400 Da as determined by sodium dodecylsulfatepolyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration chromatography, respectively, and the enzyme exists in a monomeric form. The physicochemical properties of the enzyme were as follows: optimum pH at 7.5, optimum temperature at $60^{\circ}C$, and pI at 4.9. The $K_m$ and $V_{max}$ values of the enzyme were 4.3 mM and 2.5 mmol/min/mg, respectively, with MetAla-Ser as substrate. The B. subtilis PepT requires $Co^{2+}$ ion(s) for activation, while it is inactivated by EOTA and 1,10-phenanthroline, suggesting that it is a metalloprotein. The enzyme was not inhibited by any of serine protease, aspartic protease, or leucine aminopeptidase inhibitors. The enzyme showed comparable activities towards four different substrates including Met-Ala-Ser, Leu-Gly-Gly, Leu-Ser-Phe, and Leu-Leu-Tyr. The amino terminal sequence of PepT determined by Edman degradation was found to be MKEEIIERFTTYVXV and turned out to be identical to that of PepT deduced from a cloned B. subtilis pepT.