• Journal of the Korean Society of Industry Convergence
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• v.2 no.1
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• pp.77-83
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• 1999

Grown in the secondary broth of production media, the strain Streptomyces albulus has increased more the production of its metabolite ${\varepsilon}$-poly-L-lysine, one of poly(amino acid)s used as disinfecting food additives, than the strain in the primary culture of growth nutrients. Having the strain removed, the large concentrate obtained by ultrafiltrating the secondary culture broth. The concentrated production broth exchanged into followed by detecting in UV flowcell at 220nm the peptide bond of the components eluting the adsorbed proteins and polylysine with NaCl salt of gradient concentration, and has separated into five components. Among them the component in the fourth peak fraction has proved to be the pure ${\varepsilon}$-poly-L-lysine after the portion being hydrolyzed the fraction with HCl into amino acid followed by being the composing amino acid analysis.

• Mass Spectrometry Letters
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• v.6 no.3
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• pp.80-84
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• 2015

Here, we demonstrate the use of MALDI-TOF as a fast and simple analytical approach to evaluate the DNA-binding capability of various peptides. Specifically, by varying the amino acid sequence of the peptides consisting of lysine (K) and tryptophan (W), we identified peptides with strong DNA-binding capabilities using MALDI-TOF. Mass spectrometric analysis reveals an interesting novel finding that lysine residues show sequence selective preference, which used to be considered as mediator of electrostatic interactions with DNA phosphate backbones. Moreover, tryptophan residues show higher affinity to DNA than lysine residues. Since there are numerous possible combinations to make peptide oligomers, it is valuable to introduce a simple and reliable analytical approach in order to quickly identify DNA-binding peptides.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.802-805
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• 2001

The dapD gene of Brevibacterium lactofermentum encoding tetrahydrodipicolinate N-succinyl transferase, one of the enzymes involved in lysine biosynthesis, was cloned by complementation of Escherichia coli dapD mutnat. The recombinant plasmid pLS1 was found to contain a 3.6 kb DNA fragment. Southern hybridization analysis confirmed that the cloned DNA fragment originated from B. lactofermentum. The data of L-lysine production showed that the B. lactofermentum dapD gene was expressed in E. coli.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1529-1536
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• 2008

Acetylation of lysine residues in proteins is a reversible and highly regulated posttranslational modification. However, it has not been systematically studied in prokaryotes. By affinity immunoseparation using an anti-acetyllysine antibody together with nano-HPLC/MS/MS, we identified 125 lysine-acetylated sites in 85 proteins among proteins derived from Escherichia coli. The lysine-acetylated proteins identified are involved in diverse cellular functions including protein synthesis, carbohydrate metabolism, the TCA cycle, nucleotide and amino acid metabolism, chaperones, and transcription. Interestingly, we found a higher level of acetylation during the stationary phase than in the exponential phase; proteins acetylated during the stationary phase were immediately deacetylated when the cells were transferred to fresh LB culture medium. These results demonstrate that lysine acetylation is abundant in E. coli and might be involved in modifying or regulating the activities of various enzymes involved in critical metabolic processes and the synthesis of building blocks in response to environmental changes.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.356-359
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• 2000

The study was conducted to evaluate the nutritional value of seeds and various seed fractions of different varieties of cotton (MNH 147, CIM 240, NIAB 78, FH 87, CIM 109, MNH 93, FH 682, GOHAR 87, SLS I and B 557). Linter, hull, kernel and meal were obtained from cottonseed by physical and chemical methods. Free gossypol and available lysine contents of seed and it's fractions were determined. In vitro protein digestibility of cottonseed meal was also determined. Free gossypol and available lysine contents ranged between 0.22-2.26% and 0.64-1.32% in seed, and 0.03-0.29% and 1.38-2.36% in meal, respectively. FH 87 was highest both in free gossypol and available lysine content, and NIAB 78 was lowest in free gossypol content and FH 862 was lowest in available lysine content. In vitro protein digestibility of cottonseed meal ranged between 66,02-79,96%. Statistical analysis revealed significant (p<0.05) varietal differences in free gossypol, available lyslne and in vitro protein digestibility of cottonseed and derived products.

• Journal of Nutrition and Health
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• v.12 no.2
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• pp.65-74
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• 1979

In order to observe the contents of some essential amino acids in Korean foods, total and free tryptophan, and available lysine in fifty kinds of Korean foods were analyzed by the sfectrophotometry. The results obtained are summarized as follows : 1) The tryptophan contents per 100g of soybean, wet green laver and skim milk were over 250 mg, and the contents Per g nitrogen in ginger, dried persimmon and chestnut were over 150 mg. 2) The free tryptophan contents per 100 g of soybean, small red bean, dried persimmon, ginseng stem were over 100 mg, ana the contents per g nitrogen in dried persimmon was over 150 mg. 3) The available lysine contents Per 100g of soybean, wet green laver and skim milk, fish(auchovy), dried yeast, casein and silkworm pupa were over 1000 mg, and the contents per g nitrogen in potato, perilla(wild sesame), red pepper, sausage and skim milk were over 300mg. 4) The contents of tryptophan and available lysine in soybean, green laver and skim milk were higher than in other samples. 5) In general, the contents of tryptophan and available lysine were abundant in seaweeds.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.385-395
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• 2010

The objective of this study was to determine optimal lysine requirement of lactating Mong Cai sows and their piglets. An experiment was conducted using 30 Mong Cai sows in a factorial randomized design with 5 dietary total lysine levels (0.60, 0.70, 0.85, 1.0 and 1.15%) for one-week pre-partum and 5 dietary total lysine levels (0.60, 0.75, 0.90, 1.05 and 1.2%) for lactation diets. Mong Cai sows were about 1 to 2 years old and had an initial body weight of 120 kg (sd = 2.5) after farrowing. Sows were restrictively fed 1.7 kg feed during gestation and were fed ad libitum during lactation. Diets of sows contained about 12% CP during pregnancy and about 14% CP for the lactation period. DE concentration of the diets ranged between 12.5-13.0 MJ of DE. Water was supplied at up to 8 liters per sow per day in a basin. Studied traits were related to both sows and their progeny. Sows were weighed at 107 days of gestation, after farrowing and at weaning. Sow back-fat depth was measured at 110 days of gestation, after farrowing, at 21 days of lactation and at weaning. Number of piglets born, at 24 h after birth, at 21 days of age and at weaning were recorded. Piglets were weighte at birth, at 21 days and at weaning. Supplying lysine one week pre-partum had no effect on the number of piglets born nor litter weight at birth (p = 0.776 and p = 0.224). A positive effect of increasing dietary lysine level during lactation from 0.60 to 1.20% was observed with regard to less sow weight loss, and increased piglet weight at 21 days and at weaning. The level of lysine that resulted in the lowest sow backfat loss and the highest weaned piglet weight was 1.05%; this may be the optimum level of lysine for the diet of lactating Mong Cai sows. At this lysine level, the number of weaned piglets was also highest.

• Journal of Life Science
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• v.14 no.3
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• pp.478-483
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• 2004

In a model reaction using lysyl oxidase purified partilally from bovine aorta, effect of L-ascorbic acid AsA on the oxidative reaction of lysine in collagen was investigated. Addition of Ash to the reaction mixture under aerobic conditions resulted in the decrease of enzymatic activity. In order to examine the specificity of AsA in the oxidative reaction of lysine, other reductants including A derivatives instead of AsA were added to the reaction mixture. Thiol such as glutathione had no effect on the activities of lysyl oxidase. on the other hand, it was observed that erythorbic acid, which was a stereoisomer of AsA, had the same inhibitory effect on this oxidative reaction as AsA. Moreover, by the addition of 3,4-dihydroxybenzoate, which was structural analog of AsA, the activities decreased in a similar manner to that of AsA. These results indicate that the regulatory effect of AsA on lysyl oxidase is attributed to characteristics of the structure. From the determination of Ash remained in the reaction mixture, it is shown that AsA concentration remarkably decreased by lysyl oxidase of the reaction mixture. It is hypothesized that endiol groups reduces the enzyme-bound $Cu^{+2}$ required for further progress of the reaction, and suggests that AsA regulates specifically the reduction of $Cu^{+2}$ required to oxidize lysyl oxidase. This findings support that AsA has an important regulatory role on the oxidative reaction of lysine and on changes of collagen cross-links with aging.

• Journal of Nutrition and Health
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• v.21 no.4
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• pp.197-212
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• 1988

To study the effect of preventing the browning reaction between casein and glucose by protecting the reactants using corn starch with coating material, rats were fed for 30 days nonbrowning diet, nonprotected browning diet, browning diet protected only casein, browning diet protected both casein and glucose and browning diet supplement sucrose simultaneously with protecting both casein and glucose. The amounts of fructosyl-lysine excreted through urine were greater than those through feces regardless of diets and the both side of the excreted amounts of fructosly-lysine through urine or feces were greater for rats fed browning diets regardless protecting compared to rats fed the nonbrowning diet. Through urine, the excreted amounts of fructosyl-lysine were decreased for rats fed the browning diet supplemented sucrose simultaneously with protecting both casein and glucose than those for rats fed the nonprotected browning diet and through feces, were decreased for rats fed protected browning diets regardless of protecting method than the nonprotected browning diet. The excreted amounts of all individual essential free amino acids through feces were increased for rats fed browning diets irrespective of protecting compared to the nonbrowning diet, but through urine, were increased or similar level for rate fed the nonbrowning diet compared to browning diets except histidine. The excreted amount of free lysine through feces were decreased for rats fed protected browning diets than nonprotected browning diet. Fructosyl-lysine contents of serum, liver and small intestinal digesta were increased for rats fed browning diets regardless of protecting by starch compared to nonbrowning diet but, of serum and small intestinal digesta were decreased for rats fed protected browning diets than the nonprotected browning diet.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.564-572
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• 2013

Two trials were conducted to investigate the effect of decreasing the crude protein (CP) content of diets for finishing pigs containing two levels of available lysine on nutrient digestibility, nitrogen (N) balance and production performance. Ten finishing diets containing five levels of CP (on average 144, 155, 168, 182 and 193 g/kg fresh basis) and two levels of available lysine (6.9 and 8.2 g/kg fresh basis) were formulated. The diets were offered to pigs on a performance trial (n = 800 Large White (LW)${\times}$Landrace (LR) pigs) from 10 wk of age until finish at 21 wks+5 d of age. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated. In addition, a digestibility/N balance trial was conducted using pigs (n = 80 $LW{\times}LR$) housed in metabolism crates. Digestibility of dry matter (DM), CP, oil, fibre and energy was determined. N balance values were determined through analysis of N content of urine and faeces ('as determined'). N balance values were also calculated using ADG values and assuming that 16% of growth is protein deposition ("as calculated"). Pig performance was poor between 10 and 13 wk of age which indicated that the dietary treatments were nutritionally inadequate for pigs less than 40 kg. There was a significant (p<0.01) quadratic effect of increasing CP level on feed intake, ADG and FCR from 10 to 13 wk which indicated that the lower CP levels did not supply adequate levels of essential or non-essential amino acids. There was no effect of increasing available lysine level throughout the early period, which in conjunction with the response in older pigs, suggested that both 8.2 and 6.9 g/kg available lysine were insufficient to drive optimum growth. There was a positive response (p<0.05) to increasing available lysine level from 13 wk to finish which indicated that 6.9 g/kg available lysine was not adequate for finishing pigs. Energy digestibility decreased with decreasing CP level of diets containing 6.9 g/kg available lysine which may be attributed to the higher fibre content of the lower CP diets. Nitrogen excretion (g/d) was lowered when dietary CP was reduced regardless of whether the values were determined through balance or calculated using ADG. Calculated N excretion decreased linearly (p<0.001) and quadratically (p<0.001) with decreasing dietary CP content. When the N balance figures calculated in this study were compared with those quoted in the Northern Ireland and English Nitrates Directive Action Programmes, N excretion was less per pig (wean to finish) offered a 169 g/kg CP, 8.2 g/kg available lysine diet (2.39 kg vs 3.41 kg (Northern Ireland) and 2.93 kg (England)).