• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.334-340
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• 2005

Lectin is a cell-agglutinating and carbohydrate-binding protein present in many plants. The lectin of Canavalia ensiformis shoot with specific affinity for D-glucose was purified by affinity chromatography using Sephadex G-100, and some of its biochemical characterizations were studied. Lectin was purified 8.87-fold and exhibited final specific activity of 225.74 units/mg protein with a $2.3\%$ yield. SDS-PAGE analysis demonstrated that the purified shoot lectin exists as a tetramer of 102 kD, composed of two subunits with molecular weight of 29 and 22 kD. The purified lectin was observed to agglutinate rabbit blood cell. The optimal temperature for the activity of this lectin was $40^{\circ}C$, and this lectin was relatively stable to heat with the highest activity at $50{\~}60^{\circ}C$. The maximal activity was observed at pH 7.2.

• 약학회지
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• 제39권1호
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• pp.24-30
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• 1995

Lectin from mistletoe(Viscum coloratum) fermented by Lactobacillus plantarum was compared with the lectin from unfermented mistletoe. Agglunating activity of fermented mistletoe was stable at pH 3.77~8.71, at temperature range of $0~40^{\circ}C$ and in the presence of 9 mental ions, which results are similar to unfermented one, but less stable at pH 2.03~3.00 and more stable at temperature $60~80^{\circ}C$ than lectin from unfermented one. Agglunating activity of lectin from mistletoe fermented for 1 or 2 days and from fraction number 42~54 was not inhibited by all sugars used except for lectin from fraction number 21~34. Mitogenic activity to murine lymphpocytes of lectin from mistletoe was decreased by fermentation process.

• Archives of Pharmacal Research
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• 제20권4호
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• pp.306-312
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• 1997

We attempted to isolate and characterize the lectins from stem and leaves of Korean mistletoe (Viscum album var. coloratum) by affinity chromatography. Lectin I was isolated only from stem. Lectin II was not isolated from Korean mistletoe, whereas lectin III was isolated from the stem and leaves. The hemagglutinating activity of lectin I was 16HU and inhibited by D-galactose, lactose, and N-acetyl-D-galactosamine. The lectin I has molecular weight of 60, 000D being composed of two basic subunits with molecular weights of 32, 000D and 28, 000D which are linked by a disufide bond. The lectin III from stem has molecular weight of 66, 000D being two basic subunits which have molecular weights of 34, 000D and 29, 000D and are linked by a disufide bond. The activity of lectin I was stable at the pH range of 4.00-8.50 and at a wide range of temperature (0-42.deg. C). The lectin I showed more potent mitogenic activity to murine lymphocytes than concanavalin A.

• 약학회지
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• 제44권6호
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• pp.607-612
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• 2000

Generally, antitumor drugs have strong toxicity and result in damage in normal cells. Previously, lectin has been reported as a tumor cell specific binding protein and tannin as an antitumor substance. In this study, we investigated antitumor activity of lectin-conjugated ellagitannin and used praecoxin A as an ellagitannin source. We injected mouse melanoma cell, B16-F10, on right the femoral region of C57BL/6 mouse. After 10 hours later, first treatment with praecoxin A, lectin-praecoxin A mixiture and lectin-conjugated praecoxin A was carried and followed by injection i.m. every 48 hours. Praecoxin A extended the life of mice up to 14.8% in comparison with the negative control group at 5 mg/kg dose. The life extending ratio of Lectin-praecoxin A mixture was 26.1% at 5 mg/kg dose, and the life extending ratio of lectin-conjugated praecoxin A was 28.7% at 5 mg/kg dose. On the basis of these findings, we suggest that antitumor activities of lectin-praecoxin A mixiture and lectin-conjugated praecoxin A on survival are better than that of praecoxin A.

• 약학회지
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• 제51권4호
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• pp.259-263
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• 2007

We previously reported the isolation of a sialic acid-specific lectin eluted from the bark of Maackia fauriei using alkaline buffer on a fetuin-affinity column. Application of a borate-based elution buffer in the present study increased the specific activity of purified lectin from crude protein extract by 2.6-fold, whilst only slightly decreasing the recovery by 1.13%. The biological properties of the lectin eluted with borate buffer were the same as those of the lectin eluted with alkaline buffer such as in terms of the hemagglutination activity, hemagglutination inhibition activity, molecular mass, purity, and cytotoxicity to human breast cancer cells. A prepared biotin-labeled lectin conjugate was used to investigate the binding to various glycoproteins. Our results indicate that eluting with borate buffer is more efficient than using alkaline buffer to isolate the lectin adsorbed in a fetuin-affinity column.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1173-1179
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• 2009

Trypsin inhibitors and lectins are defense proteins produced by many organisms. From Chinese 'Large Black Soybeans', a 60 kDa lectin and a 20 Da trypsin inhibitor (TI) were isolated using chromatography on Q-Sepharose, Mono Q, and Superdex 75. The TI inhibited trypsin and chymotrypsin with an $IC_{50}$ of 5.7 and $5{\mu}M$, respectively. Trypsin inhibitory activity of the TI was stable from pH 3 to 13 and from 0 to $65^{\circ}C$. Hemagglutinating activity of the lectin was stable from pH 2 to 13 and from 0 to $65^{\circ}C$. The TI was inhibited by dithiothreitol, signifying the importance of disulfide bond. The TI and the lectin inhibited HIV-1 reverse transcriptase ($IC_{50}$=44 and $26{\mu}M$), and proliferation of breast cancer cells ($IC_{50}$=42 and $13.5{\mu}M$) and hepatoma cells ($IC_{50}$=96 and $175{\mu}M$). The hemagglutinating activity of the lectin was inhibited most potently by L-arabinose. Neither the lectin nor the TI displayed antifungal activity.

• Journal of the Korean Wood Science and Technology
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• 제29권4호
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• pp.79-88
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• 2001

표고버섯(Lentinula edodes) 으로부터 0.15 M NaCl 용액에 의하여 crude lectin을 추출하였으며, 황산암모늄에 의한 침전 음이온교환수지 및 hydroxyapatite 컬럼을 이용한 크로마토그래피에 의하여 정제하였다. 버섯균산과 균병으로 나누어 추출된 crude lectin의 양에 있어서는 균산부분이 균병부분에 비하여 2배 이상 높은 lectin을 함유하였으며, 가열한 버섯에서는 lectin의 함량 및 활성은 미처리보다 감소되었다. 건조된 균산 50 g으로부터 얻은 crude lectin은 720 mg으로서 46.03%의 수율로 얻었으며, DEAE Sephadex A-50 column에 의한 분리, 정제 후 정제된 lectin 201 mg을 crude lectin의 28% 수율로 얻을 수 있었다. Crude lectin을 정제함으로서 aspartic acid, serine, alanine 및 histidine등의 아미노산이 증가되었고, glutamic acid, glycine, leucine, tyrosine 및 methionine 등이 lectin에는 검색되지 않았다. DEAE Sephadex A-50 column의 chromatograpy를 통해 분리 정제한 활성을 지니는 lectin의 주된 부분은 Agglutinating test 결과, fraction A 및 B는 적혈구응집활성을 나타냈으며, 약 23 kDa의 분자량을 가지고 있었다. 활성을 지니는 부분을 다시 hydroxyapatite column에 의해 정제하여 얻은 LA-a와 LB-b는 각각 24 kDa과 23 kDa의 분자량을 나타냈다.

• KSBB Journal
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• 제23권1호
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• pp.48-53
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• 2008

토마토의 locular fluid로부터 최종적으로 Sephadex G-200 affinity chromatography에 의해 lectin을 분리한 다음, 이들의 분자량, 적혈구 응집력, 혈액특이성, 열 안정성, 최적 온도 및 pH 안정성의 생화학적 성질을 연구하였다. SBS-PAGE의 결과, 분자량이 39 kDa와 23 kDa로서 각각 2개의 subunit로 구성된 124 kDa의 분자량을 가지는 tetramer이다. 트립신으로 처리된 사람의 A, B, O, AB형의 혈액을 사용하여 각각의 혈구응집반응을 확인한 결과, A, B, O, AB형 모두에서 응집반응이 일어났으며, 이 중 B형 혈액에서 가장 높은 활성을 나타냈으며, A와 O형은 중간, AB형은 가장 낮은 활성을 보였다. 분리된 토마토 locular fluid의 최적반응 온도는 $50^{\circ}C$로서, 가장 높은 $70^{\circ}C$를 포함하는 $40-80^{\circ}C$에서 열 안정성을 보였으며, 이의 최적 pH는 7.0이다.

• 생명과학회지
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• 제18권3호
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• pp.350-356
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• 2008

가지 열매로부터 neutral saline에 의한 추출, $(NH_4)_2SO_4$ 침전 및 Sephadex-G100을 이용한 affinity chromatography에 의해 분리한 lectin의 생화학적 특성을 연구하였다. Trypsin을 처리하지 않은 사람, 쥐와 토끼의 적혈구에서는 혈구 응집반응이 일어나지 않았으며, Trypsin을 처리한 사람, 쥐와 토끼의 적혈구 중에서는 쥐의 적혈구에서만 혈구 응집반응이 일어났다. SDS-PAGE에 의해 가지 lectin의 분자량을 확인한 결과, 19.3 kDa의 단일 band 임이 확인되었다. D-glucose를 포함하는 7개의 탄수화물은 100 mM 이하의 농도에서 lectin과 적혈구의 응집을 저해시키지 않았으므로, 탄수화물에 대한 특이성이 나타나지 않았다. 최적 반응온도 범위는 $10-20^{\circ}C$로서, $20-70^{\circ}C$에서 열에 대해 안정하였으며, 안정된 pH 범위는 pH 6.2-7.2로 확인되었다. $Ca^{2+},\;Co^{2+},\;Cu^{2+},\;Fe^{2+},\;Mg^{2+}$ 및 $Mn^{2+}$ 20 mM 이하의 농도에서는 lectin과 적혈구의 응집을 저해시키지 않았으므로, 금속이온에 대한 특이성이 나타나지 않았다

• The Korean Journal of Physiology and Pharmacology
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• 제15권4호
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• pp.241-244
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• 2011

A lectin from the hemolymph of purse crab, Philyra pisum, was found to have anti-proliferative activity on human lung cancer cells by our laboratory. In this study, P. pisum lectin (PPL) was molecularly characterized including molecular mass, amino acid sequences, amino acid composition, and the effects of metal ions, temperature, and pH on the activity. We found that PPL showed mitogenic activity on human lymphocytes and BALB/c mouse splenocytes. The mitogenic activity (maximum stimulation index, $SI=9.57{\pm}0.59$) of PPL on human lymphocytes was higher than that of a standard well-known plant mitogen, concanavalin A (maximum $SI=8.80{\pm}0.59$). The mitogenic activity mediated by PPL is required for optimum dosing, and higher or lower concentrations caused decreases in mitogenic response. PPL also induced mitogenic activity on mouse splenocytes, however, the maximum SI ($1.77{\pm}0.09$) on mouse splenocytes of PPL was lower than that ($2.14{\pm}0.15$) of concanavalin A. In conclusion, PPL is a metal ion-dependent monomer lectin with mitogenic activity, and could be used as a lymphocyte or splenocyte stimulator.