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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Society for Biochemistry and Molecular Biology
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Volume & Issues
Volume 38, Issue 6 - Nov 2005
Volume 38, Issue 5 - Sep 2005
Volume 38, Issue 4 - Jul 2005
Volume 38, Issue 3 - May 2005
Volume 38, Issue 2 - Mar 2005
Volume 38, Issue 1 - Jan 2005
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Molecular Chaperones in Protein Quality Control
Lee, Suk-Yeong ; Tsai, Francis T.F. ;
BMB Reports , volume 38, issue 3, 2005, Pages 259~265
DOI : 10.5483/BMBRep.2005.38.3.259
Proteins must fold into their correct three-dimensional conformation in order to attain their biological function. Conversely, protein aggregation and misfolding are primary contributors to many devastating human diseases, such as prion-mediated infections, Alzheimer's disease, type II diabetes and cystic fibrosis. While the native conformation of a polypeptide is encoded within its primary amino acid sequence and is sufficient for protein folding in vitro, the situation in vivo is more complex. Inside the cell, proteins are synthesized or folded continuously; a process that is greatly assisted by molecular chaperones. Molecular chaperones re a group of structurally diverse and mechanistically distinct proteins that either promote folding or prevent the aggregation of other proteins. With our increasing understanding of the proteome, it is becoming clear that the number of proteins that can be classified as molecular chaperones is increasing steadily. Many of these proteins have novel but essential cellular functions that differ from that of more 'conventional' chaperones, such as Hsp70 and the GroE system. This review focuses on the emerging role of molecular chaperones in protein quality control, i.e. the mechanism that rids the cell of misfolded or incompletely synthesized polypeptides that otherwise would interfere with normal cellular function.
Structure and Function of HtrA Family Proteins, the Key Players in Protein Quality Control
Kim, Dong-Young ; Kim, Kyeong-Kyu ;
BMB Reports , volume 38, issue 3, 2005, Pages 266~274
DOI : 10.5483/BMBRep.2005.38.3.266
High temperature requirement A (HtrA) and its homologues constitute the HtrA familiy proteins, a group of heat shock-induced serine proteases. Bacterial HtrA proteins perform crucial functions with regard to protein quality control in the periplasmic space, functioning as both molecular chaperones and proteases. In contrast to other bacterial quality control proteins, including ClpXP, ClpAP, and HslUV, HtrA proteins contain no regulatory components or ATP binding domains. Thus, they are commonly referred to as ATP-independent chaperone proteases. Whereas the function of ATP-dependent chaperone-proteases is regulated by ATP hydrolysis, HtrA exhibits a PDZ domain and a temperature-dependent switch mechanism, which effects the change in its function from molecular chaperone to protease. This mechanism is also related to substrate recognition and the fine control of its function. Structural and biochemical analyses of the three HtrA proteins, DegP, DegQ, and DegS, have provided us with clues as to the functional regulation of HtrA proteins, as well as their roles in protein quality control at atomic scales. The objective of this brief review is to discuss some of the recent studies which have been conducted regarding the structure and function of these HtrA proteins, and to compare their roles in the context of protein quality control.
Protein Folding and Diseases
Lee, Cheol-Ju ; Yu, Myeong-Hee ;
BMB Reports , volume 38, issue 3, 2005, Pages 275~280
DOI : 10.5483/BMBRep.2005.38.3.275
For most of proteins to be active, they need well-defined three-dimensional structures alone or in complex. Folding is a process through which newly synthesized proteins get to the native state. Protein folding inside cells is assisted by various chaperones and folding factors, and misfolded proteins are eliminated by the ubiquitin-proteasome degradation system to ensure high fidelity of protein expression. Under certain circumstances, misfolded proteins escape the degradation process, yielding to deposit of protein aggregates such as loop-sheet polymer and amyloid fibril. Diseases characterized by insoluble deposits of proteins have been recognized for long time and are grouped as conformational diseases. Study of protein folding mechanism is required for better understanding of the molecular pathway of such conformational diseases.
Distinct Differences between TNF Receptor 1- and TNF Receptor 2- mediated Activation of NFκB
Thommesen, Liv ; Laegreid, Astrid ;
BMB Reports , volume 38, issue 3, 2005, Pages 281~289
DOI : 10.5483/BMBRep.2005.38.3.281
Tumor necrosis factor (TNF) signaling is mediated via two distinct receptors, TNFR2 and TNFR1, which shows partially overlapping signaling mechanisms and biological roles. In the present study, TNFR2 and TNFR1 signal transduction mechanisms involved in activation of
and CMV promoter-enhancer were compared with respect to their susceptibility towards inhibitors of intracellular signaling. For this, we used SW480 cells, where we have shown that TNF-signaling can occur independently through each of the two receptors. The TNFR1 response was inhibited by D609, bromophenacyl bromide (BPB), nordihydroguararetic acid (NDGA), and by sodium salicylate, while TNFR2-mediated activation of
and CMV promoter-enhancer was resistant to these compounds. The signaling mechanisms known to be affected by these inhibitors include phospholipases as well as redox- and pH-sensitive intracellular components. Our results imply that TNFR2 signaling involved in
activation proceeds independently of these inhibitor-sensitive signaling components, indicating distinct signaling pathways not shared with TNFR1.
Screening of the Antigen Epitopes of Basic Fibroblast Growth Factor by Phage Display
Xiang, Junjian ; Zhong, Zhenyu ; Deng, Ning ; Zhong, Zhendong ; Yang, Hongyu ;
BMB Reports , volume 38, issue 3, 2005, Pages 290~293
DOI : 10.5483/BMBRep.2005.38.3.290
In order to investigate the epitope of basic fibroblast growth factor (bFGF) and its immunogenicity, the epitopes of bFGF were screened from the phage display library with monoclonal antibody GF22, which can neutralize the bio-activity of bFGF. By three rounds of screening, the positive phage clones with bFGF epitopes were selected, which can effectively block the bFGF to bind with GF22. Sequence analysis showed that the epitopes shared a highly conservative sequence (Leu-Pro-Pro/Leu-Gly-His-Phe/Ile-Lys). The sequence of PPGHFK was located at 22-27 of the bFGF. The specific immuno-response of mouse could be highly induced by phage clones with the epitopes. And the anti-bFGF activity induced by LPGHFK was 3 times higher than the original sequence, which showed that the mimetic peptide LPLGHIK might be used as a tumor vaccine in the prevention and treatment of tumor.
Production of Recombinant Humanized Anti-HBsAg Fab Fragment from Pichia pastoris by Fermentation
Deng, Ning ; Xiang, Junjian ; Zhang, Qing ; Xiong, Sheng ; Chen, Wenyin ; Rao, Guirong ; Wang, Xunzhang ;
BMB Reports , volume 38, issue 3, 2005, Pages 294~299
DOI : 10.5483/BMBRep.2005.38.3.294
In this report, we describe the high-yield secretory expression of the recombinant human anti-HBsAg Fab fragment from Pichia pastoris that was achieved by co-integration of the genes encoding the heavy and light chains (both under the control of alcohol oxidase promoter) into the genome of the yeast cells. The fed-batch fermentations were carried out in a 5 L scale. Both chains of the Fab were successfully expressed upon methanol induction. The absorbance (
) of the broth can reach 350~500 at the end of fed-batch phase. After the induction, the expression level of the recombinant Fab (soluble) reached 420~458 mg/L. The recombinant Fab fragment was purified from the crude culture supernatant by ion exchange chromatography and the purity of the recombinant Fab fragment was over 95%. The affinity activities of the crude fermentation supernatant and the purified Fab were analyzed by indirect ELISA, which showed that the purified recombinant Fab fragment had high affinity activity with hepatitis B surface antigen.
The Effect of Dimethyl Dimethoxy Biphenyl Dicarboxylate (DDB) against Tamoxifen-induced Liver Injury in Rats: DDB Use Is Curative or Protective
El-Beshbishy, Hesham A. ;
BMB Reports , volume 38, issue 3, 2005, Pages 300~306
DOI : 10.5483/BMBRep.2005.38.3.300
Tamoxifen citrate is an anti-estrogenic drug used for the treatment of breast cancer. It showed a degree of hepatic carcinogenesis, when it used for long term as it can decrease the hexose monophosphate shunt and thereby increasing the incidence of oxidative stress in liver rat cells leading to liver injury. In this study, a model of liver injury in female rats was done by intraperitoneal injection of tamoxifen in a dose of 45 mg/kg body weight for 7 successive days. This model produced a state of oxidative stress accompanied with liver injury as noticed by significant declines in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant elevations in TBARS (thiobarbituric acid reactive substance) and liver transaminases; sGPT (serum glutamate pyruvate transaminase) and sGOT (serum glutamate oxaloacetate transaminase) levels. The oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) in a dose of 200 mg/kg body weight daily for 10 successive days, resulted in alleviation of the oxidative stress status of tamoxifen-intoxicated liver injury in rats as observed by significant increments in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases; sGPT and sGOT levels. The administration of DDB before tamoxifen intoxication (as protection) is more little effective than its curative effect against tamoxifen-induced liver injury. The data obtained from this study speculated that DDB can mediate its biochemical effects through the enhancement of the antioxidant enzyme activities and reduced glutathione level as well as decreasing lipid peroxides.
Preliminary Proteomic Analysis of Thiobacillus ferrooxidans Growing on Elemental Sulphur and Fe
He, Zhi-guo ; Hu, Yue-Hua ; Zhong, Hui ; Hu, Wei-Xin ; Xu, Jin ;
BMB Reports , volume 38, issue 3, 2005, Pages 307~313
DOI : 10.5483/BMBRep.2005.38.3.307
Thiobacillus ferrooxidans is one of the most important bacterium used in bioleaching, and can utilize
or sulphide as energy source. Growth curves for Thiobacillus ferrooxidans have been tested, which show lag, logarithmic, stationary and aging phases as seen in other bacteria. The logarithmic phases were from 10 to 32 hours for Thiobacillus ferrooxidans cultivated with
and from 4 to 12 days for Thiobacillus ferrooxidans cultivated with elemental sulphur. Differences of protein patterns of Thiobacillus ferrooxidans growing on elemental sulphur and
separately were investigated after cultivation at
by the analysis of two-dimensional gel electrophoresis (2-DE), matrix-assisted laser desorption/ ionization (MALDI)-Mass spectrometry and ESI-MS/MS. From the 7 identified protein spots, 11 spots were found more abundant when growing on elemental sulphur. By contrast 6 protein spots were found decreased at elemental cultivation condition. Among the proteins identified, cytochrome C have been previously identified as necessary elements of electron-transfering pathway for Thiobacillus ferrooxidans to oxidize
; ATP synthase alpha chain and beta are expressed increased when Thiobacillus ferrooxidans cultivated with
as energy source. ATP synthase Beta chain is the catalytic subunit, and ATP synthase alpha chain is a regulatory subunit. The function of ATPase produces ATP from ADP in the presence of a proton gradient across the membrane.
Adenosine Induced Apoptosis in BHK Cells via P1 Receptors and Equilibrative Nucleoside Transporters
Sun, Wentian ; Khoo, Hoon Eng ; Tan, Chee Hong ;
BMB Reports , volume 38, issue 3, 2005, Pages 314~319
DOI : 10.5483/BMBRep.2005.38.3.314
Adenosine, as a ubiquitous metabolite, mediates many physiological functions via activation of plasma membrane receptors. Mechanisms of most of its physiological roles have been studied extensively, but research on adenosine-induced apoptosis (AIA) has only started recently. In this study we demonstrate that adenosine dose-dependently triggered apoptosis of cultured baby hamster kidney (BHK) cells. Adenosine-induced apoptotic cell death was characterized by DNA laddering, changes in nuclear chromatin morphology and phosphatidylserine staining. Apoptosis was also quantified by flow cytometry. Results suggest the involvement of adenosine
receptors as well as equilibrative nucleoside transporters in apoptosis induced by adenosine. These results indicate a receptor-transporter co-signaling mechanism in AIA in BHK cells. The involvement of
receptors also implies a possible apoptotic pathway mediated by G protein-coupled receptors.
Hybrid 'Sinta' Papaya Exhibits Unique ACC Synthase 1 cDNA Isoforms
Hidalgo, Marie-Sol P. ; Tecson-Mendoza, Evelyn Mae ; Laurena, Antonio C. ; Botella, Jose Ramon ;
BMB Reports , volume 38, issue 3, 2005, Pages 320~327
DOI : 10.5483/BMBRep.2005.38.3.320
Five ripening-related ACC synthase cDNA isoforms were cloned from 80% ripe papaya cv. 'Sinta' by reverse transcription-PCR using gene-specific primers. Clone 2 had the longest transcript and contained all common exons and three alternative exons. Clones 3 and 4 contained common exons and one alternative exon each, while clone 1, the most common transcript, contained only the common exons. Clone 5 could be due to cloning artifacts and might not be a unique cDNA fragment. Thus, there are only four isoforms of ACC synthase mRNA. Southern blot analysis indicates that all five clones came from only one gene existing as a single copy in the 'Sinta' papaya genome. Multiple sequence alignment indicates that the four isoforms arise from a single gene, possibly through alternative splicing mechanisms. All the putative alternative exons were present at the 5'-end of the gene comprising the N-terminal region of the protein. 'Sinta' ACC synthase cDNAs were of the capacs 1 type and are most closely related to a 1.4 kb capacs 1-type DNA(AJ277160) from Eksotika papaya. No capacs 2-type cDNAs were cloned from 'Sinta' by RT-PCR. This is the first report of possible alternative splicing mechanism in ripening-related ACC synthase genes in hybrid papaya, possibly to modulate or fine-tune gene expression relevant to fruit ripening.
Expression of Sara2 Human Gene in Erythroid Progenitors
Jardim, Denis Leonardo Fontes ; Cunha, Anderson Ferreira Da ; Duarte, Adriana Da Silva Santos ; Santos, Camila Oresco Dos ; Saad, Sara Terezinha Olalla ; Costa, Fernando Ferreira ;
BMB Reports , volume 38, issue 3, 2005, Pages 328~333
DOI : 10.5483/BMBRep.2005.38.3.328
A human homologue of Sar1, named Sara2, was shown to be preferentially expressed during erythropoiesis in a culture stimulated by EPO. Previous studies, in yeast, have shown that secretion-associated and Ras-related protein (Sar1p) plays an essential role in protein transport from the endoplasmic reticulum to the Golgi apparatus. Here, we report the molecular analysis of Sara2 in erythroid cell culture. A 1250 bp long cDNA, encoding a 198 amino-acid protein very similar to Sar1 proteins from other organisms, was obtained. Furthermore, we also report a functional study of Sara2 with Real-time quantitative PCR analysis, demonstrating that expression of Sara2 mRNA increases during the initial stages of erythroid differentiation with EPO and that a two-fold increase in expression occurs following the addition of hydroxyurea (HU). In K562 cells, Sara2 mRNA was observed to have a constant expression and the addition of HU also up-regulated the expression in these cells. Our results suggest that Sara2 is an important gene in processes involving proliferation and differentiation and could be valuable for understanding the vesicular transport system during erythropoiesis.
Induction of Peripheral Tolerance in Dual TCR T Cells: an Evidence for Non-dominant Signaling by One TCR
Hah, Chae-Rim ; Kim, Mi-Hyung ; Kim, Kil-Hyoun ;
BMB Reports , volume 38, issue 3, 2005, Pages 334~342
DOI : 10.5483/BMBRep.2005.38.3.334
Recently, the existence of T cells with dual T cell receptor (TCR) in the immune system is generally accepted, while it has been controversial whether signals through one TCR would affect the functions of the other. In this study T cells expressing two different TCR were obtained from cross-hybrids of LCMV and AND TCR transgenic mice specific for the gp33 and peptide fragment of PCC (fPCC), respectively. Peptide stimulation demonstrated that the dual TCR T cells functioned independently in an antigen-specific manner. To examine whether the tolerance targeted for the one TCR affects the responsiveness of the other, the cross-hybrids were treated with gp33. Although T cells from F1 mice were rendered anergenic to gp33, no functional changes to fPCC were observed in terms of cellular proliferation and IL-2 secretion, suggesting that the dual TCR T cells remained reactive to fPCC. We therefore propose that signaling through the TCR is receptor-specific and 'negative dominance' of one TCR by tolerance induction is not applicable in this dual TCR system.
Activity Determination, Kinetic Analyses and Isoenzyme Identification of Gamma Glutamyltransferase in Human Neutrophils
Sener, Azize ; Yardimci, Turay ;
BMB Reports , volume 38, issue 3, 2005, Pages 343~349
DOI : 10.5483/BMBRep.2005.38.3.343
Gamma-glutamyltransferase (GGT, EC 18.104.22.168) which hydrolyzes glutathione (GSH), is required for the maintenance of normal intracellular GSH concentration. GGT is a membrane enzyme present in leukocytes and platelets. Its activity has also been observed in human neutrophils. In this study, GGT was purified from Triton X-100 solubilized neutrophils and its kinetic parameters were determined. For kinetic analyses of transpeptidation reaction,
-glutamyl p-nitroanilide was used as the substrate and glycylglycine as the acceptor. Apparent
values were determined as 1.8 mM for
-glutamyl p-nitroanilide and 16.9 mM for glycylglycine. The optimum pH of GGT activity was 8.2 and the optimum temperature was
. It had thermal stability with 58% relative activity at
for 30 min incubation. L-serine, in the presence of borate, was detected as the competetive inhibitor. Bromcresol green inhibited neutrophil GGT activity as a noncompetetive inhibitor. The neutrophils seem to contain only the isoenzyme that is present in platelets. We characterized the kinetic properties and compared the type of the isoenzyme of neutrophil GGT with platelet GGT via polyacrylamide gel electrophoresis (PAGE) under a standart set of conditions.
Study of Alanine-73 and Aspartate-9 of HLA-C Locus in Saudi Psoriasis Patients, Using Sequence-specific Primers (PCR-SSP)
Abanmi, Abdullah ; Harthi, Fahad Al ; Agla, Rokaiyah Al ; Khan, Haseeb Ahmad ; Tariq, Mohammad ;
BMB Reports , volume 38, issue 3, 2005, Pages 350~353
DOI : 10.5483/BMBRep.2005.38.3.350
Alanine at residue 73 (Ala-73) and aspartate at residue 9 (Asp-9) are characteristic to both Cw6 and Cw7 alleles of HLA-C gene and have been suggested as possible markers for psoriasis vulgaris (PsV). However, the results from various ethnic groups/populations are contradictory and inconclusive. In this study, an attempt has been made to examine the association between HLA-C (Ala-73 and Asp-9) and susceptibility to PsV among Saudi patients. Genomic DNA was extracted from 25 Saudi PsV patients and 75 control subjects. Polymerase chain reaction (PCR) was performed to amplify HLA-C sequences using earlier reported primers, C133P and C243PR. Sequence-specific primers were used to specifically detect nucleotide coding for Ala-73 and Asp-9 in all the subjects. The results showed significantly higher frequency of Asp-9 (84.0% versus 61.3%) in PsV patients as compared to controls (p < 0.05, 2-tailed Fisher's exact test). The frequencies of Ala-73 among PsV patients (92%) and controls (88%) did not differ significantly.
Characterization of Ha29, a Specific Gene for Helicoverpa armigera Single-nucleocapsid Nucleopolyhedrovirus
Guo, Zhong-Jian ; An, Shi-Heng ; Wang, Dun ; Liu, Yan-He ; Kumar, V. Shyam ; Zhang, Chuan-Xi ;
BMB Reports , volume 38, issue 3, 2005, Pages 354~359
DOI : 10.5483/BMBRep.2005.38.3.354
Open reading frame 29 (ha29) is a gene specific for Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HearSNPV). Sequence analyses showed that the transcription factor Tfb2 motif, bromodomain and Half-A-TPR (HAT) repeat were present at aa 66-82, 4-76, 55-90 of the Ha29 protein respectively. The product of Ha29 was detected in HearSNPV-infected HzAM1 cells at 3 h post-infection. Western blot analysis using a polyclonal antibody produced by immunizing a rabbit with purified GST-Ha29 fusion protein indicates that Ha29 is an early gene. The size of Ha29 product in infected HzAM1 cells was about 25 kDa, which was larger than the presumed size of 20.4 kDa. Tunicamycin treatment of HearSNPV-infected HzAM1 cells suggested that the Ha29 protein is N-glycosylated. Fluorescent confocal laser scanning microscope examination, and Western blot analysis of purified budded virus (BVs), occlusion-derived virus (ODVs), cell nuclear and cytoplasmic fraction, showed that the Ha29 protein was localized in the nucleus. Our results suggested that ha29 of HearSNPV encodes a non-structurally functional protein that may be associated with virus gene transcription in Helicoverpa hosts.
Polyphosphoinositides Are Derived from Ether-linked Inositol Glycerophospholipids in Rat Brain
Shin, Sun-H. ; Kim, Jong-S. ; Kim, Hak-R. ; Lim, Jin-K. ; Choi, Byung-K. ; Yeo, Young-K. ;
BMB Reports , volume 38, issue 3, 2005, Pages 360~365
DOI : 10.5483/BMBRep.2005.38.3.360
Membrane inositol glycerophospholipid (IGP) is metabolized to phosphatidylinositol-4-phosphate (PIP), phosphatidylinositol-4, 5-bisphosphate (
), and inositol triphosphate (
) in signaling transduction. This study was carried out to determine the subclasses of IGP involved in signaling pathway. The acyl chain moieties of the phospholipids are easily modulated by dietary fatty acids. We analyzed acyl chain composition of IGP 3-subclasses, PIP and
from rat brain after feeding sunflower seed oil enriched with linoleic acid or fish oil high in eicosapentaenoic acid and docosahexaenoic acid. Long chain polyunsaturated fatty acids (LCPUFA) as eicosapentaenoic acid and docosahexaenoic acid were not incorporated into ether-linked IGP (alkenylacylglycerophosphoinositol and alkylacyl-glycerophosphoinositol), PIP and
, while diacyl-glycerophosphoinositol (GPI) contained high LCPUFA. These results suggest that PIP might be phosphorylated from only the ether-linked IGP (alkenylacyl- and alkylacyl species) but not from diacyl subclass for signals to intracellular responses in the plasma membrane of rat brain.
A Continuous Spectrophotometric Assay for NADPH-cytochrome P450 Reductase Activity Using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide
Yim, Sung-Kun ; Yun, Chul-Ho ; Ahn, Tae-Ho ; Jung, Heung-Chae ; Pan, Jae-Gu ;
BMB Reports , volume 38, issue 3, 2005, Pages 366~369
DOI : 10.5483/BMBRep.2005.38.3.366
NADPH-cytochrome P450 reductase (CPR) transfers electrons from NADPH to cytochrome P450 and also catalyzes the one-electron reduction of many drugs and foreign compounds. Various spectrophotometric assays have been performed to examine electron-accepting properties of CPR and its ability to reduce cytochrome
, cytochrome c, and ferricyanide. In this report, reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) by CPR has been assessed as a method for monitoring CPR activity. The principle advantage of this substance is that the reduction of MTT can be assayed directly in the reaction medium by a continuous spectrophotometric method. The electrons released from NADPH by CPR were transferred to MTT. MTT reduction activity was then assessed spectrophotometrically by measuring the increase of
. MTT reduction followed classical Michaelis-Menten kinetics (
). This method offers the advantages of a commercially available substrate and short analysis time by a simple measurement of enzymatic activity of CPR.
Cross-linked Leucaena Seed Gum Matrix: An Affinity Chromatography Tool for Galactose-specific Lectins
Seshagirirao, Kottapalli ; Leelavathi, Chaganti ; Sasidhar, Vemula ;
BMB Reports , volume 38, issue 3, 2005, Pages 370~372
DOI : 10.5483/BMBRep.2005.38.3.370
A cross-linked leucaena (Leucaena leucocephala) seed gum (CLLSG) matrix was prepared for the isolation of galactose-specific lectins by affinity chromatography. The matrix was evaluated for affinity with a known galactose-specific lectin from the seeds of snake gourd (Trichosanthes anguina). The matrix preparation was simple and inexpensive when compared to commercial galactose-specific matrices (i.e. about 1.5 US$/100 ml of matrix). The current method is also useful for the demonstration of the affinity chromatography technique in laboratories. Since leucaena seeds are abundant and inexpensive, and the matrix preparation is easy, CLLSG appears to be a promising tool for the separation of galactose-specific lectins.