• Title/Summary/Keyword: L-A-S

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Identification and Comparison of the Nucleotide Sequence of 16S-23S rRNA Gene Intergenic Small SR(Spacer Region) of Lactobacillus rhamnosus ATCC 53103 with Those of L. casei, L. acidophilus and L. helveticus

  • Byun, J.R.;Yoon, Y.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.12
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    • pp.1816-1821
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    • 2003
  • Reliable PCR based identification of lactobacilli has been described utilizing the sequence of 16S-23S rRNA intergenic spacer region. Those sequence comparisons showed a high degree of difference in homology among the strains of L. rhamnosus, L. casei, L. acidophilus and L. helveticus whose 16S-23S rRNA intergenic small SR's sizes were 222 bp, 222 bp, 206 bp and 216 bp respectively. The sequence of 16S-23S rRNA intergenic spacer region of L. rhamnosus ATCC 53103 revealed the close relatedness to those of L. casei strains by the homology ranges from 95.4% to 97.2%. 16S-23S rRNA intergenic spacer region nucleotide sequence of L. acidophilus showed some distant relatedness with L. rhamnosus ATCC 53103 with the homology ranges from 40.3% to 41.8% and that with L. helveticus was shown to be 30% of homology, which exists at the most distant phylogenetic relatedness. The identification of species and strain of lactobacilli was possible on the basis of these results. The common sequences among the 17 strains were CTAAGGAA located in the initiating position of the DNA and some discrepancies were found between the same strains based on these results.

Synthesis of Nuclophilic Adducts of Thiols (Ⅵ). Addition of L-Cystein to $\beta,\;\beta$-Diethoxycarbonylstyrene Derivatives

  • kim, Tae-Rin;Cho, Bong-Rae;Choi, Sung-Yong;Choi, Won-Sik
    • Bulletin of the Korean Chemical Society
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    • v.5 no.6
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    • pp.215-218
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    • 1984
  • A series of S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-cysteine derivatives (10a-e) were synthesized from the reaction of $\beta$$\beta$-diethoxycarbonylstyrene with L-cysteine in 1:1 aqueous methanol. Thus, S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-cysteine( 10a), S-[2,2-diethoxycarbonyl-1-(3',4'-methylendioxy)ph enylethyl]-L-cysteine (10b), S-[2,2-diethoxycarbonyl-1-(3',4',5'-trimethoxy)phe nylethyl]-L-cyseine (10c), S-[2,2-diethoxycarbonyl-1-(p-hydroxy)phenylethyl] -L-cysteine (10d), S-[2,2-diethoxycarbonyl-1-(p-methoxy)phenylethyl] -L-cysteine (10e) were obtained in moderate to excellent yields. The structure of the adducts was characterized by analytical and spectral data. The effects of pH upon the product yields were also briefly examined.

Phytosociological Studies on the Beech(Fagus multinervis Nakai) Forest and the Pine (Pinus parviflora S. et Z.) Forest of Ulreung Island, Korea (한국 울릉도의 너도밤나무(Fagus multinervis Nakai)림 및 섬잣나무(Pinus parviflora S. et Z.)림의 식물사회학적 연구)

  • 김성덕
    • Journal of Plant Biology
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    • v.29 no.1
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    • pp.53-65
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    • 1986
  • The montane forests of Ulreung Island, Korea, were investigated by the ZM school method. By comparing the montane forests of this island with those of Korean Peninsula and of Japan, a new order, F a g e t a l i a m u l t i n e r v i s, a new alliance, F a l g i o n m u l t i n e r v i s, a new association, H e p a t i c o-F a g e t u m m u l t i n e r v i s and Rhododendron brachycarpum-Pinus parviflora community were recognized. The H e p a t i c o - F a g e t u m m u l t i n e r v i s was further subdivided into four subassociations; Subass. of Sasa kurilensis, Subass. of Rumohra standishii, Subass. of Rhododendron brachycarpum and Subass. of typicum. Each community was described in terms of floristic, structural and environmental features.

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A Study on Nuclear Information Management System Utilizing Microcomputer (마이크로 컴퓨터를 이용한 원자력 분야 정보 관리 시스템 개발)

  • 김규선;김태승
    • Journal of the Korean Society for information Management
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    • v.6 no.1
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    • pp.15-36
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    • 1989
  • The r a p i d i n c r e a s e o f microcomputer technology has r e s u l t e d i n t h e broad a p p l i c a t i o n t o various f i e l d s . The purpose of t h l s paper 1s to design a computerized r e t r i e v a l system f o r nuclear information m a t e r i a l s using a microcomputer.

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Synthesis of Nucleophilic Adducts of Thiols (Ⅰ). Addition of Cysteine to $\beta$-Nitrostyrene Derivatives

  • Kim, Tae-Rin;Choi, Sung-Yong
    • Bulletin of the Korean Chemical Society
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    • v.2 no.4
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    • pp.125-129
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    • 1981
  • The addition reactions of cysteine without blocking amino and carboxyl groups to substituted and unsubstituted ${\beta}$-nitro-styrene derivatives were investigated. ${\beta}$-Nitrostyrene(1a), p-methyl-${\beta}$-nitrostyrene(1b), 3,4,5-trimethoxy-$[\beta}$ -nitrostyrene(1c), $[\varpi}$-3,4-methylenedioxy-${\beta}$ -nitrostyrene(1d), o-, m- and p-chloro-${\beta}$ -nitrostyrene (1e, 1f, 1g) and o-, m- and p-methoxy-${\beta}$-nitrostyrene (1h, 1i, 1j) easily undergo addition reactions with cysteine to form S-(2-nitro-1-phenylethyl)-L-cysteine(3a), S-[2-nitro-1-(p-methyl)phenyl-ethyl]-L-cysteine(3b), S-[2-nitro-1-(3',4',5'-trimethoxy) phenylethyl]-L-cysteine(3c), S-[2-nitro-1-($[\vatpi}$ -3',4'-methylenedioxy)phenylethyl]-L-cysteine(3d), S-[2-nitro-1-(o-chloro)phenylethyl]-L-cysteine(3e), S-[2-nitro-1-(m-chloro)-phenylethyl]-L-cysteine(3f), S-[2-nitro-1-(p-chloro)phenylethyl]-L-cysteine(3g), S-[2-nitro-1-(o-methoxy)phenylethyl]-L-cysteine(3h), S-[2-nitro-1-(m-methoxy)phenylethyl]-L-cysteine(3i) and S-[2-nitro-1-(p-methoxy)phenylethyl]-L-cysteine(3j), respectively. The structure of adducts were confirmed by means of UV-spectrum, IR-spectrum, molecular weight measurement and elemental analysis. The various factors effecting the yield of cysteine adducts to ${\beta}$-nitrostyrene derivatives were also studied.

Synthesis of Nucleophilic Adducts of Thiols (XI). Addition of L-Cysteine to $\beta,\beta$-Dinitrostyrene Derivatives

  • Kim, Tae-Rin;Kim, Jae-Hoon;Choi, Won-Sik
    • Bulletin of the Korean Chemical Society
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    • v.9 no.3
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    • pp.115-117
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    • 1988
  • The addition of L-cysteine without blocking amino and carboxyl groups to${\beta},{\beta}$-dinitrostyrene derivatives(11a-e) were investigated. ${\beta},{\beta}$ -Dinitrostyrene derivatives(11a-e) easily undergo addition reactions with L-cysteine to from s-(2,2-dinitro-1-phenylethyl)-L-cysteine(12a), s-[2,2-dinitro-1-(p-methyl)phenylethyl]-L-cysteine (12b), s-[2,2-dinitro-1-(p-methoxy)phenylethyl]-L-cystein e(12c), s-[2,2-dinitro-1-(p-chloro)phenylethyl]-L-cysteine (12d) and s-[2,2-dinitro-1-(p-nitro)phenylethyl]-L-cysteine( 12a), respectively. The structure of adducts were confirmed by means of spectral data, molecular weight measurement and elemental analysis.

N,N'-Dimethylethylenediamine-N,N'-di-α-butyric Acid Cobalt(III) Complexes Utilizing Oxidation of Sulfur of S-Methyl-L-cysteine

  • Kim, Hyun-Jin;Youm, Kyoung-Tae;Yang, Jung-Sung;Jun, Moo-Jin
    • Bulletin of the Korean Chemical Society
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    • v.23 no.6
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    • pp.851-856
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    • 2002
  • The Reaction of S-methyl-S-cysteine(L-Smc) with racemic $s-cis-[Co(demba)Cl_2]-1$ (Hydmedba = $NN'-dimethylethylenediamine-NN'-di-\alpha-butyric$, acid) yields ${\Delta}$-s-cis-[Co(dmedba)(L-Smc)] 2 with N, O-chelation. Oxidation of sulfur of 2 with $H_2O_2$ in a 1 : 1 mole ratio gives ${\Delta}$-s-cis[Co(dmedba)(L-S(O)mc)] 3 having an uncoordinated sulfenate group. Oxidation of sulfur of L-Sm with $H_2O_2in$ a 1: 1 mole ratio produces S-methyl-L-cysteinesulfenate (L-S(O)me) 5. Direct reaction of 1 with 5 in basic medium gives an N.O-chelated ${\Delta}$s-cis[Co(dmedba)(L-S(O)mc)-N.O], which turmed out be same as obtained by oxidation of 2, while an N, S-chelated ${\Delta}$-s-cis-[Co(dmedba)(S-S(O)mc)-N,O] complex 4 is obtained in acidic medium from the reaction of 1 with 5. This is one of the rare $[$Co^{III}$(N_2O_2-type$ ligand)(amino acid)] type complex preparations, where the reaction conditions determine which mode of N, O and N, S caelation modes is favored.

Alanine and S-Methylcysteine Cobalt (III) Complexes of Ethylenediamine-N,N'-di-${\alpha}$-butyric Acid

  • Moo-Jin Jin;Jio Woo Cheon;Sung Rack Choi
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.251-253
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    • 1990
  • L-Alanine(L-ala) and S-methyl-L-cysteine(L-mcy) cobalt(III) complexes of a flexible $N_2O_2$-type tetradentate ligand ethylenediamine-N,N'-di- -butyric acid(eddb), s-cis-[Co(eddb)(L-ala)] and s-cis-[Co(eddb)(L-mcy), have been prepared via the substitution reactions of the s-cis-$[Co(eddb)Cl_2]$-complex with, respectively, L-alanine and S-methyl-L-cysteine. Both L-alanine and S-methyl-L-cysteine are found to coordinate to the cobalt(III) ion via the nitrogen and oxygen donor atoms to give the meridional s-cis isomer. Electronic absorption, ir and pmr spectra are used to characterize the complexes obtained in this work along with elemental analysis data.

Newly Recorded Naturalized Species in Korea, Silene antirrhina L. (Caryophyllaceae) (한국 미기록 귀화식물: 가는끈끈이장구채(석죽과))

  • Bak, Gyu-Jin;Koh, Jae-Kee;Pak, Jae-Hong
    • Korean Journal of Plant Taxonomy
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    • v.41 no.2
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    • pp.171-174
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    • 2011
  • A naturalized species, Silene antirrhina L is newly reported in Korea. S. antirrhina L. was found along the Geumho riverside in Daegu. S. antirrhina L. is similar to S. koreana Kom. and S. armeria L. in that it has dark glutinous areas. S. antirrhina L. can be distinguished from congeneric species by the stamens and styles of its sepal and seed surface which are finely papillate. The Korean name of S. antirrhina L. "Ganeun-Kkunkkunijangguchea" was newly formulated based on the overall characteristics of this thin and small plant and on the Korean name of S. koreana Kom. photos of the habitat and a description and key of characteristics are provided.

ON CHOWLA'S HYPOTHESIS IMPLYING THAT L(s, χ) > 0 FOR s > 0 FOR REAL CHARACTERS χ

  • Stephane R., Louboutin
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.1
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    • pp.1-22
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    • 2023
  • Let L(s, χ) be the Dirichlet L-series associated with an f-periodic complex function χ. Let P(X) ∈ ℂ[X]. We give an expression for ∑fn=1 χ(n)P(n) as a linear combination of the L(-n, χ)'s for 0 ≤ n < deg P(X). We deduce some consequences pertaining to the Chowla hypothesis implying that L(s, χ) > 0 for s > 0 for real Dirichlet characters χ. To date no extended numerical computation on this hypothesis is available. In fact by a result of R. C. Baker and H. L. Montgomery we know that it does not hold for almost all fundamental discriminants. Our present numerical computation shows that surprisingly it holds true for at least 65% of the real, even and primitive Dirichlet characters of conductors less than 106. We also show that a generalized Chowla hypothesis holds true for at least 72% of the real, even and primitive Dirichlet characters of conductors less than 106. Since checking this generalized Chowla's hypothesis is easy to program and relies only on exact computation with rational integers, we do think that it should be part of any numerical computation verifying that L(s, χ) > 0 for s > 0 for real Dirichlet characters χ. To date, this verification for real, even and primitive Dirichlet characters has been done only for conductors less than 2·105.