• 미생물학회지
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• 제23권1호
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• pp.20-24
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• 1985

Klebsiella pnellmoniae의 nif-lac융합변이주를 사용하여 질소고정 유전자 발현에 미치는 질소원의 효과를 검토하였다. Klebsiella pnellmoniae UN4482를 heat induction하여 만든 Mudllysate를 K. pnellmoniae U UN2979에 접종시켜 nif-lac융합체 약 80여주를 분리하고 이들을 LX series로 명하였다. 이들의 ${\beta}-galactosidase$ 한성은 $NH_4^+$의 존재하에 크게 억제되었다. Serine, glutamine, asparagine같은 아미노산을 켈소원으로 사용했을때 K. pnellmoniae의 성장은 양호하였으며. NFHM배지에서nif-lac융합주LX-9, LX-22의 ${\beta}-galactosidase$의 환성은 억제 효과도 높았으나, glutamine, histidine, arginine 같은 amino acid는 위와 반대 의 효과플 나타냈다. Casitone, prote-ose peptone같은 유기섣소원(2 mg/ml )의 균성장에 대한효과는 전반적으로양호했으나LX-9, LX-22 의 ${\beta}-galactosidase$활성에 대한 억제효과는 각 칠소원에 따라 다르게 나타났다. 한편, 질소원이 없는 최소배지에서의 LX-9와 L LX-22의 ${\beta}-galactosidase$의 활성은 초기 4 시간내에 급격히 증가하였다.

• Preventive Nutrition and Food Science
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• 제5권3호
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• pp.153-159
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• 2000

A 4.4 kb DNA fragment encompassing lacA (galactoside acetyltransferase) and lacZ($\beta$-galactosidase) genes from Lactococus lactis ssp. lactis ATCC 7962 (L. lactis 7962) was introduced ito a Lac strain, Lactococcus lactis ssp. lactis MG1363 (L. lactis MG1363) by using a lactococcal expression vector, pMG36e and expression level of lacZ was examined. Growth rates and $\beta$-galactosidase ($\beta$-gal) activities of MG1363 cells carrying recombinant plasmid, pMLZ3, on M17 broth containing different carbon sources (1%, w/v) were examined. Contrary to the expectations, MG1363 [pMLZ3] grown on lactose showed the lowest enzyme activity (17 units) and cells grown on galactose had the highest $\beta$-gal activity (41 units). Cells grown on glucose had intermediate activity (33 units). These activities are about one tenth of the values observed in L. lactis 7962 where lacZ is present as a single-copy gene in the chromosome. When the cellular concentrations of lacZ transcript were examined using slot blot hybridization, it was found that MG1363[pMLZ3] produced sufficient amounts of transcript. These results indicate that either proteolytic degradation of $\beta$-gal or other regulatory mechanism prevent the translation or accumulation of $\beta$-gal in L. lactis MG1363 cells. In regard to regulation, the presence of the ccpA gene in L. lactis MG1363 was confirmed by Southern blot.

• Journal of Ginseng Research
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• 제22권4호
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• pp.310-315
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• 1998

The effect of red ginseng saponins (total saponins, Rbl- and Rgl- fraction of saponins) on the induction of $\beta$-galactosidase in yeast, hccharomyces cereuisiae, was investigated to see that ginseng saponins would penetrate the cell membrane and have a function in a nucleus as steroid hormones do. To attain such a kind of purpose, a DNA fragment (685bp) containing GALI promoter was inserted into the sites of EcoRl and BamHl of polylinker region, upstream of lace gene of the plasmid YEp356 (7.966 Kb), and thus the resulting plasmid pGALl-lacZ is supposed to express $\beta$- galactosidase only in the presence of galactose. The plasmid pGALl -lacZ was introduced into yeast, Ky106 (a leu2 ura3 his3 trp 1 Iys2), and the growth of the transformed cells was much slower in the presence of galactose than glucose. The effects of saponins on the specific activity of P-galactosidase from transformed yeast cells were detected. No significant increase was observed in case of total saponins, but the Rbl- or Rgl- fraction of saponins gave much higher increase in the activity. Maximum increase was observed as 35% in 10-3% of Rbl and as 75% in 10-1% of Rgl. These data suggest that ginseng saponins might be able to enter the nucleus and stimulate transcription. However, further studies to find out the putative saponin receptor are needed to confirm this possibility. Key words : Red ginseng saponin, $\beta$-galactosidase induction, Saccharomyces cerevisiae.

• 미생물학회지
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• 제46권4호
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• pp.397-400
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• 2010

만난의 분해활성을 갖는 Paenibacillus woosongensis의 배양 상등액으로부터 mannanase, ${\beta}$-mannosidase와 ${\alpha}$-galactosidase 활성이 관찰되었다. 배양상등액 내의 locust bean gum를 분해하는 mannanase는 pH 5.5와 $60^{\circ}C$, para-nitrophenyl-${\beta}$-D-mannopyranoside를 분해하는 ${\beta}$-mannosidase는 pH 6.5, $50^{\circ}C$, para-nitrophenyl-${\alpha}$-D-galactopyranoside를 분해하는 ${\alpha}$-galactosidase는 pH 6.0-6.5와 $50^{\circ}C$에서 각각 최대활성을 보였다. 배양상등액의 만난 분해효소는 mannotriose, mannotetraose, mannopentaose, mannohexaose와 같은 만노올리고당을 분해할 뿐 아니라 mannobiose도 분해하였다. 또한 melibiose, raffinose, stachyose 등의 ${\alpha}$-1,6 결합형 galacto-oligosaccharides를 분해하여 galactose를 생성하였다. 이러한 결과로 보아 P.woosongensis는 galactomannan을 완전히 분해하는데 필요한 3종류 효소를 모두 생산하는 것으로 판단된다.

• 한국미생물·생명공학회지
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• 제17권1호
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• pp.35-45
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• 1989

Streptococcus thermophilus 510으로부터 $\beta$-galactosidase의 생성조건은 탄소원으로 0.5% lactose를 첨가한 배지에서 초기 pH7.0, 배양온도 37$^{\circ}C$, 배양기간 18시간이었다. 배양여액으로부터 $\beta$-galactosidase를 ammonium sulfate 분획, 핵산의 제거, Sephadex G-200 gel filtration 및 DEAE-Sephadex A-50 ion exchange chromatography 등의 4단계 정제과정을 거쳐 정제한 결과 18배 정제되어 단일 단백질로 분리되었다. 정제효소의 활성 최적온도는 5$0^{\circ}C$, 최적 pH는 7.0이었고, 효소활성이 Mn$^{2+}$, $K^+$과 같은 금속이온과 dithiothreitol, 2-mercaptoethanol에 의해 촉진되었고, Hg$^{2+}$, $Zn^{2+}$, Co$^{2+}$, $Ca^{2+}$, EDTA, 8-hydroxyquinoline, galactose 등에 의해 저해되었다. 효소의 분자량이 520,000, 합성기질인 ONPG에 대한 $K_{m}$ 은 1,25mM, V$_{max}$는 88.50 $\mu$mole/min.mg protein이었고, 주종 아미노산은 glutainic acid, aspartic acid, leucine 및 valine이었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.118-126
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• 2004

Recombinant E.coli ACV 1003 (recA::lacZ) releasing ${\beta}$-galactosidase by a SOS regulon system, when exposed to DNA-damaging compounds, have been used to effectively monitor endocrine disruptors. Low enzyme activity of less than 10 units/mL, corresponding to a $\mu\textrm{g}$/L(ppb) range of an endocrine disruptor (tributyl tin, bisphenol A. etc.), can be rapidly determined, not by a conventional time-consuming and tedious enzyme assay, but by an alternative interferometric biosensor. Heavily boron-doped porous silicon for application as an interferometer, was fabricated by etching to form a Fabry-Perot fringe pattern, which caused a change in the refractive index of the medium including ${\beta}$-galactosidase. In order to enhance the immobilization of the porous silicon surface, a calyx crown derivative (ProLinker A) was applied, instead of a conventional biomolecular affinity method using biotin. This resulted in a denser linked formation. The change in the effective optical thickness versus ${\beta}$-galactosidase activity, showed a linear increase up to a concentration of 150 unit ${\beta}$-galactosidase/mL, unlike the sigmoidal increase pattern observed with the biotin.

• 한국식품영양과학회지
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• 제26권3호
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• pp.404-410
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• 1997

Amylase, protease, polygalacturonase and $\beta$-galactosidase activities were monitored during salting of Chinese cabbage and kimchi fermentation at 1$0^{\circ}C$. A part of enzymes in the tissue of Chinese cabbage were eluted during salting, and other remained enzymes activities were decreased in proportion to the amount of elution. But total enzyme activities were increased during salting. Amylase, protease and polygalacturonase activities decreased at the early fermentation stage but increased at the late fermentation stage. $\beta$-Galactosidase activity was continuously increased during all periods of fermentation. Enzymic actions at the early fermentation stage come from Chinese cabbge and at the late fermentation stage come from major microorganisms in kimchi fermentation. Kimchi fermentation involves the activation of the enzymes by salting; hydrolysis of micromoleculars such as polysaccarides cell wall composed polysaccarides and proteins of cell wall during early fermentation of kimchi; overripening of the kimchi caused by propagation of homofermentative lactic acid bacteria which demand autotroph.

• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.134-138
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• 2003

The secondary and tertiary structures of ${\beta}$-galactosidase from L. lactis ssp. lactis 7962 were designed using Nnpredict and Sybyl version 6.3. By using site-directed mutagenesis, the mutated enzymes, Tyr-475-phe and Glu-506-Asp, were generated based on the structural modeling of L. lactis ssp. lactis 7962. The enzymes Tyr.-475-Phe and Glu-506-Asp had <$1\%$ of the activity of the native enzyme with ONPG as substrate. The $V_{max}$ values of the mutated enzymes were greatly reduced (1,800~40,000-1314) compared with the value for the native ${\beta}$-galactosidase. However, the $K_m$ values of Tyr-475-Phe and Glu-506-Asp with ONPG, PNPG, PNPF, and PNPA were not significantly different from those of the native enzyme. The results obtained support the suggestion that Tyr-475 and Glu-506 constitute very important parts of the catalytic machinery of the ${\beta}$-galactosidase.

• 분석과학
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• 제5권4호
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• pp.471-475
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• 1992

유당분해효소를 유지방으로 미세캡슐화시켰으며, 이때의 미세캡슐화 수율을 정량적으로 분석하는 방법을 제시하였다. 본 연구에서 적용한 미세캡슐화 공정과정에 의한 유당분해효소의 불활성화 정도는 초기 효소활성도의 5.2%였으며 이러한 불활성화 정도를 고려하여 유당분해효소의 미세캡슐화 수율을 여러 가지 방법에 의하여 계산하였을 때 각각 92.6% (간접적인 측정방법), 88.6% (열처리에 의한 방법) 및 94.1% (효소처리에 의한 방법)였다.

• KSBB Journal
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• 제9권4호
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• pp.400-405
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• 1994

호말칼리성이며 고온성인 Bacillus sp. TA-11로 부터 $\beta$galactosidase를 대량생산할 목적으로 배지 조성, 배지의 초기 pH 빛 배양온도와 각종 배양방법 등이 효소생산에 미치는 영향을 검토하였다. ${\beta}$-galactosidase의 최척생산조건은 1.5% lactose, 0.6% y yeast extract, 0.15% $K_2HP0_4$ 초기 pH 9.5, 배양 온도 $50^{\circ}C$이였고 플라스크배양에서는 48시간에 약 4 4350U/ml, 회분배양에서는 36시간에 4200 4400U/ml의 효소가 생산되였다. 또한 유가배양에서 는 120시간에 5200U/ml, 연속배양에셔는 34시간에 4000U/ml의 효소가 생산되었으며 효소의 비활성은 연속배양시 약 3077U/mg으로 제일 좋았다.