• 한국산업융합학회 논문집
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• 제2권1호
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• pp.91-95
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• 1999

The Streptomyces albulus broth, when the polylysine in the broth, that has powerful growth inhibiting effect far many microbes, is its maximum, had filtered off the cells, to use the broth as preservative for keeping favorable taste of Korean Kimchi. Some microorganisms in their specific growth medium, known to deteriorate the useful nutrient of the Kimchi, has grown with different amounts of the inhibiting broth, to determine the minimum growth inhibition concentration. The ${\varepsilon}$-poly-L-lysine had been identified from the IR spectroscopic analysis of the purified poly lysine of the broth from ion exchange chromatographic separation. The content of the polylysine had been determined by methyl orange decoloration effect. Though the minimum inhibition concentration, evaluated by the naked eye based on the conventional method measuring the turbid feature after 18 hours of culture, has different values each other, the observed effects confirmed that the crude broth could be used as a natural preservative for the Kimchi in extending the fair taste.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1100-1107
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• 2007

The effects of offering broilers phosphorus-adequate diets containing 10.0 and 11.8 g/kg lysine, without and with 500 FTU/kg exogenous phytase, on growth performance and nutrient utilisation were determined. Each of the four experimental diets was offered to 6 replicates of 10 birds from 7 to 28 days of age. Effects of treatment on performance, apparent metabolisable energy, apparent ileal digestibility of amino acids and bone mineralisation were examined. Both additional lysine and phytase supplementation improved (p<0.05) weight gain and feed efficiency, with interactions (p<0.05), as phytase responses were more pronounced in lysine-deficient diets. Phytase improved (p<0.05) apparent metabolisable energy, which was independent of the dietary lysine status. Bone mineralisation, as determined by percentage toe ash, was not affected by treatment, which confirms the phosphorus-adequate status of the diets. Phytase increased (p<0.05) the apparent ileal digestibility of the sixteen amino acids assessed. Unexpectedly, however, the dietary addition of 1.8 g/kg lysine, as lysine monohydrochloride, increased (p<0.05) the ileal digestibility of lysine per se and also that of isoleucine, methionine, phenylalanine, valine, aspartic acid, glutamic acid and tyrosine. In addition, there were significant interactions (p<0.05) between additional lysine and phytase supplementation for arginine, lysine, phenylalanine, aspartic acid, glutamic acid, glycine and serine digestibilities, with the effects of phytase being more pronounced in lysine-deficient diets. The possible mechanisms underlying the increases in amino acid digestibility in response to additional lysine and the interactions between lysine and microbial phytase in this regard are discussed. Also, consideration is given to the way in which phytate and phytase may influence ileal digestibility of amino acids.

• 한국육종학회지
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• 제43권5호
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• pp.375-382
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• 2011

A chemical, MNU-induced hulless barley mutant line designated as 'Mutant 98 (M98)' was developed from a Korean hulless waxy barley cultivar, 'Chalssalbori'. The objective of the study was to determine the genetic basis of 'M98' and the possibility of using 'M98' as breeding parent to improve lysine level. Compared to 'Chalssalbori', 'M98' had large embryo and higher lysine content in both the embryo and endosperm. Significantly different lysine content in 'M98' and the other high-lysine barley mutant stocks was observed for two years. However, the genotype by year interaction was not significant. 'M98' was higher than the other high-lysine barley mutant stocks in the percentage of lysine of total amino acid composition (0.75%). The trait of shrunken endosperm of 'M98', which was typical in the high-lysine mutants, was inherited by a single recessive gene. Based on seed morphology and lysine content of $F_1$ seeds, 'M98' had a genetically different gene from the other high-lysine mutants for shrunken endosperm. Segregation of $F_2$ for plump/shrunken endosperm did not fit the expected ratio of Mendelian inheritance except for only one cross combination (GSHO1784 (lys1)/M98). The amino acid analysis of $F_5$ and $F_6$ progenies from the cross between 'M98' and 'Chalssalbori' revealed that the attempt to increase the range of lysine content of plump lines did not go beyond the limit of the average high-lysine barley germplasm.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2004년도 Annual Meeting BioExibition International Symposium
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• pp.236-241
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• 2004

In Escherichia coli, L-lysine biosynthetic pathway is composed of nine enzymatic reactions. It has been well established that most of the lysine biosynthetic genes are regulated by the lysine availability, even though they are all scattered around the chromosome without forming any multigenic operon structure. However, no transcriptional regulatory mechanism has been identified except for the activation of lysA gene by the LysR. In this study, changes in transcriptome profiles of wild type cells and lysR deletion mutant cells grown in the absence or presence of lysine were investigated by using DNA microarray technique. Microarray data analysis revealed three groups of genes whose expression varies depending on the availability of lysine or LysR or both. To further examine the regulatory patterns of lysine biosynthetic genes, lacZ operon fusions were constructed and their expression was measured under various conditions. Obtained results strongly suggest that there is an additional regulatory mechanism which senses the lysine availability and coordinates gene expression.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4627-4634
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• 2013

지구온난화 주요 원인 중에 하나인 이산화탄소의 효율적 저감을 위해 새로운 흡수제인 아미노산염 흡수제를 개발하여 이산화탄소 연속공정을 연구하였다. 이산화탄소 포집 및 저장에 소요되는 비용 중 약 70%는 이산화탄소 포집비용이며, 이산화탄소 포집 공정 중에서 이산화탄소 흡수, 재생, 열화 등 흡수제에 의한 공정유지 비용이 대부분을 차지한다. 따라서 연속공정을 통한 흡수제의 특성 평가는 새로운 흡수제 개발에 매우 중요한 요소이다. 본 연구에서는 potassium L-lysine 흡수제의 이산화탄소 흡수 재생 연속공정을 평가하여 공정 스케일업에 필요한 엔지니어링 자료를 도출하고자 하였다. 흡수제와 이산화탄소 농도 변화 등 다양한 조건에서 아미노산염 흡수제의 최적 조건을 평가하였다. 동일한 조건에서 L/G가 커질수록 이산화탄소 제거율이 높게 나타났으며, L/G 3.5에서 흡수탑과 재생탑 공정이 안정하게 유지되었다. 또한 아미노산염 흡수제는 유량 1.5 $Nm^3/h$인 상태에서 L/G 3.5, 이산화탄소 농도 10.5 vol%의 공정 조건일 때 가장 높은 이산화탄소 제거효율이 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1586-1592
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• 2016

Klebsiella pneumoniae is a gram-negative, non-motile, rod-shaped, and encapsulated bacterium in the normal flora of the intestines, mouth, skin, and food, and has decarboxylation activity, which results in generation of diamines (cadaverine, agmatine, and putrescine). However, there is no specific information on the exact mechanism of decarboxylation in K. pnuemoniae. Specifically lysine decarboxylases that generate cadaverine with a wide range of applications has not been shown. Therefore, we performed a functional study of lysine decarboxylases. Enzymatic characteristics such as optimal pH, temperature, and substrates were examined by overexpressing and purifying CadA and LdcC. CadA and LdcC from K. pneumoniae had a preference for L-lysine, and an optimal reaction temperature of 37℃ and an optimal pH of 7. Although the activity of purified CadA from K. pneumoniae was lower than that of CadA from E. coli, the activity of K. pneumoniae CadA in whole cell bioconversion was comparable to that of E. coli CadA, resulting in 90% lysine conversion to cadaverine with pyridoxal 5'-phosphate L-lysine.

• 한국미생물·생명공학회지
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• 제45권3호
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• pp.271-275
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• 2017

The expression of Deinococcus radiodurans dr1558 and pprM genes was examined for enhanced lysine production in recombinant Corynebacterium glutamicum. These genes are known to confer high tolerance to pH and osmotic shock in Escherichia coli. D. radiodurans dr1558 and pprM genes were expressed in C. glutamicum by using 6 synthetic promoters of different strengths, to evaluate the effect of expression efficiency on lysine production. Recombinant C. glutamicum expressing DR1558 under the L26 and I64 promoters showed higher lysine production than that expressing DR1558 under other promoters. Similarly, recombinant C. glutamicum expressing PprM under same promoters (L26 and I64) showed a higher increase in lysine production compared to that expressing PprM under other promoters. In the absence of $CaCO_3$ in the medium, the expression of DR1558 or PprM also increased lysine concentration in C. glutamicum depending on the promoter used. Together, these results suggest that genes involved in radiation tolerance in D. radiodurans can be used to enhance production of amino acids and their derivatives.

• 대한화학회지
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• 제10권3호
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• pp.109-113
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• 1966

By the micro-bioassay method, quantitative studies were made on the increment of body weight and changes in free-lysine and threonine contents in the liver and plasm of rats, when they were fed on sucrose diet added with 0.3% DL-methionine, 0.36% DL-threonine and 0.1% L-tryptophane. The results of the experiment were as follows: (1) The weight gain and growth gain of rats decreased more when they were fed on 0.36% DL-threonine diet (Sth-group) than 0.3% DL-methionine diet (Sm-group). But those gain were increased when they were fed on 0.1% L-tryptophane diet (Str-group). (2) The contents of free-lysine and threonine in plasm and liver of rats were decreased more when they were fed on 0. 36% DL-threonine diet than 0.3% DL-methionine diet. And, those free amino acids were increased greatly when they were fed on 0.1% L-tryptophane diet. (3) The increment of body weight was the biggest when the free amino acid pattern showed that the contents of free-lysine decreased and threonine increased in the plasm and liver of rats being fed on 0.l% L-tryptophane diet.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.150-155
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• 1988

L-Lysine 생산균주인 Brevibacterium flavum ATCC 14067 과 Corynebacteriurn glutamicum ATCC13032에 섬유소 자화능이 우수한 Cellulomonas flavigena KFCC31221를 속간 융합시켜 섬유소로부터 L-lysine을 생산할 목적으로 이들 균주의 영양요구성 변이주 분리, 원형질체의 형성 및 재생의 조건을 조사하였다. NTG(500$\mu\textrm{g}$/$m\ell$)로 유기하여 penicillin-G(300$\mu\textrm{g}$/$m\ell$)로 농축한 변이주에서 B. flavum은 hse- str$^{r}$(100$\mu\textrm{g}$/$m\ell$), C. glutamicum는 Met$^{-}$T$hr^{-}$ Rif$^{r}$(5$\mu\textrm{g}$/$m\ell$), C. flavigena 는 T$hr^{-}$Val$^{-}$Kan$^{r}$(50$\mu\textrm{g}$/$m\ell$)의 gene marker를 가지는 영양요구성과 약제내성균주를 분리하였다. 공시균주의 원형질체 형성은 osmotic stabilizer로서는 0.5M sucrose, 배양기간은 대수증식기 중기의 균이 양호하였고, lysozyme 최적 처리 pH, 온도, 농도 및 반응시간은 각각 pH6.5, 33$^{\circ}C$, 500 $\mu\textrm{g}$/$m\ell$, 6시간으로 나타났으며, 이때의 원형질체형성율은 95-98%였다. 원형질체를 1.5% agar가 함유된 완전재생용 배지위에 0.7% agar가 함유된 완전재생용 배지로 중층했을 때 약 30~33%의 재생율을 보였다.

• 한국식품영양과학회지
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• 제30권5호
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• pp.802-805
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• 2001

산업적으로 lysine 발효 산업에 이용되고 있는 B. lactofermentum으로부터 lysine 생합성에 관여하는 tetrahyrodipicolinate N-succinyl transferase를 지령하는 dapD 유전자를 E. coli의 dapD 결손변이주와의 complementation test를 통하여 cloning하였다. 재조합 plamid는 3.6 kb의 DNA 단편을 함유하고 있었으며 Southern blot hybridization을 통하여 dapD 유전자는 B. lactofermentum으로부터 유래하였으며 염색체 DNA내에 single copy로 존재함을 알 수 있었다. 또한 lysine 생성량 분석을 통하여 E. coli에서 B. lactofermentum dapD 유전자의 발현을 확인하였다.