scholarly journals Characterization of the C-type lectin from the marine sponge (Stylissa flexibilis)

2020 ◽  
Vol 17 (4) ◽  
pp. 729-737
Author(s):  
Le Dinh Hung ◽  
Dinh Thanh Trung

A lectin from the marine sponge Stylissa flexibilis, designated as SFL, was purified by cold ethanol precipitation followed by ion exchange chromatography on DEAE Sepharose column and Sephacryl S-200 gel filtration. SFL is a dimeric glycoprotein of 32 kDa subunits linked by a disulfide bridge with a molecular mass of 64 kDa by SDS-PAGE and 65 kDa by Sephacryl S-200 gel filtration chromatography. The lectin preferentially agglutinated enzyme treated human A erythrocytes, whereas it did not agglutinate any type of rabbit, human B and O erythrocytes, irrespective of treatment with enzymes. The hemagglutination activity of lectin was strongly inhibited by monosaccharide, D-galactose and glycoproteins, asialo-porcine stomach mucin and asialo-fetuin, indicating that lectin is specific for O-glycans. Activity of SFL was stable over a range of pH from 5 to 8, up to 60 °C for 30 min and its activity was Ca2+ dependent, indicating that SFL was belonged to the C-type lectin family and requires metal for biological activity. SFL caused agglutination of Vibrio alginolyticus and V. parahaemolyticus in a dose dependent manner and inhibited the growth rate of these bacterial strains, suggesting that the lectin caused the agglutination through binding to the target receptor(s) on the surface of Vibrios. Thus, SFL can be considered as a good source of lectin(s) being useful as carbohydrate probe and antibacterial reagent.

2017 ◽  
Vol 18 (2) ◽  
pp. 1-10 ◽  
Author(s):  
Dzun Noraini Jimat ◽  
Intan Baizura Firda Mohamed ◽  
Azlin Suhaida Azmi ◽  
Parveen Jamal

A newly bacterial producing L-asparaginase was successful isolated from Sungai Klah Hot Spring, Perak, Malaysia and identified as Bacillus sp. It was the best L-asparaginase producer as compared to other isolates. Production of L-asparaginase from the microbial strain was carried out under liquid fermentation. The crude enzyme was then centrifuged and precipitated with ammonium sulfate before further purified with chromatographic method. The ion exchange chromatography HiTrap DEAE-Sepharose Fast Flow column followed by separation on Superose 12 gel filtration were used to obtain pure enzyme. The purified enzyme showed 10.11 U/mg of specific activity, 50.07% yield with 2.21 fold purification. The purified enzyme was found to be dimer in form, with a molecular weight of 65 kDa as estimated by SDS-PAGE. The maximum activity of the purified L-asparaginase was observed at pH 9 and temperature of 60°C.


2005 ◽  
Vol 37 (6) ◽  
pp. 363-370 ◽  
Author(s):  
Ye-Yun Li ◽  
Chang-Jun Jiang ◽  
Xiao-Chun Wan ◽  
Zheng-Zhu Zhang ◽  
Da-Xiang Li

Abstractβ-Glucosidases are important in the formation of floral tea aroma and the development of resistance to pathogens and herbivores in tea plants. A novel β-glucosidase was purified 117-fold to homogeneity, with a yield of 1.26%, from tea leaves by chilled acetone and ammonium sulfate precipitation, ion exchange chromatography (CM-Sephadex C-50) and fast protein liquid chromatography (FPLC; Superdex 75, Resource S). The enzyme was a monomeric protein with specific activity of 2.57 U/mg. The molecular mass of the enzyme was estimated to be about 41 kDa and 34 kDa by SDS-PAGE and FPLC gel filtration on Superdex 200, respectively. The enzyme showed optimum activity at 50 °C and was stable at temperatures lower than 40 °C. It was active between pH 4.0 and pH 7.0, with an optimum activity at pH 5.5, and was fairly stable from pH 4.5 to pH 8.0. The enzyme showed maximum activity towards pNPG, low activity towards pNP-Galacto, and no activity towards pNP-Xylo.


2018 ◽  
Vol 13 (12) ◽  
pp. 1934578X1801301
Author(s):  
Huiqin Wang ◽  
Guanzhen Gao ◽  
Lijing Ke ◽  
Jianwu Zhou ◽  
Pingfan Rao

A novel lectin-like protein with MW 63.2 kDa, designated as SBLP, has been isolated and characterized from the dried roots of Scutellaria baicalensis Georgi (Lamiaceae). SBLP was purified by ammonium sulfate precipitation and anion exchange chromatography. It is a glycoprotein according to a PAS staining assay and consisting of protein (86.0%) and sugar (14.0%). Its N-terminal amino acid sequence was determined as GSAVGFLY by Edman degradation. SBLP showed hemagglutinating activity against human and rooster erythrocytes, which were stable below 60°C and in the pH range of 4 −10. Furthermore, SBLP was found to be stimulated by Ca2+, Na+, Ba2+, Zn2+ ions, which suggested it was a metal-dependent lectin. SBLP inhibited the growth of Fusarium oxysporum f.sp. lycopersici and Alternaria eichhorniae in the a dose-dependent manner, and suppressed the proliferation of HepG2 tumor cells with an IC50 of 1.00 μM. This is the first report of a lectin from Radix Scutellariae.


1994 ◽  
Vol 40 (1) ◽  
pp. 18-23 ◽  
Author(s):  
Andreas Prokop ◽  
Peter Rapp ◽  
Fritz Wagner

Production of extracellular β-1, 3-glucanase activity by a monokaryotic Schizophyllum commune strain was monitored and results indicated that the β-glucanase activity consisted of an endo- β-1, 3-glucanase activity, besides a negligible amount of β-1, 6-glucanase and β-glucosidase activity. Unlike the β-1, 3-glucanase production of the dikaryotic parent strain S. commune ATCC 38548, the β-1, 3-glucanase formation of the monokaryon was not regulated by catabolite repression. The endo- β-1, 3-glucanase of the monokaryon was purified from the culture filtrate by lyophilization, anion exchange chromatography on Mono Q, and gel filtration on Sephacryl S-100. It appeared homogeneous on SDS-PAGE with a molecular mass of 35.5 kDa and the isoelectric point was 3.95. The enzyme was only active toward glucans containing β-1, 3-linkages, including lichenan, a β-1, 3-1, 4-D-glucan. It attacked laminarin in an endo-like fashion to form laminaribiose, laminaritriose, and high oligosaccharides. While the extracellular β-glucanases from the dikaryotic S. commune ATCC 38548 degraded significant amounts of schizophyllan, the endo- β-1, 3-glucanase from the monokaryon showed greatly reduced activity toward this high molecular mass β-1, 3-/β-1, 6-glucan. The Km of the endoglucanase, using laminarin as substrate, was 0.28 mg/mL. Optimal pH and temperature were 5.5 and 50 °C, respectively. The enzyme was stable between pH 5.5 and 7.0 and at temperatures below 50 °C. The enzyme was completely inhibited by 1 mM Hg2+. Growth of the monokaryotic S. commune strain was not affected by its constitutive endo- β-1, 3-glucanase formation.Key words: endo- β-1, 3-glucanase, Schizophyllum commune, monokaryon, constitutive endo- β-1, 3-glucanase formation.


2001 ◽  
Vol 86 (11) ◽  
pp. 1277-1283 ◽  
Author(s):  
Xiao-Yan Du ◽  
Alexey Navdaev ◽  
Jeannine Clemetson ◽  
Edith Magnenat ◽  
Timothy Wells ◽  
...  

SummaryA new snake protein, named bilinexin, has been purified from Agkistrodon bilineatus venom by ion-exchange chromatography and gel filtration chromatography. Under non-reducing conditions it has a mass of 110 kDa protein on SDS-PAGE. On reduction, it can be separated into five subunits with masses in the range 13-25 kDa. The N-terminal sequences of these subunits are very similar to those of convulxin or the alboaggregins, identifying bilinexin as a new member of the snake C-type lectin family, unusual in having multiple subunits. Bilinexin agglutinates fixed platelets, washed platelets and platelet rich plasma (PRP) without obvious activation (shape change) as confirmed by light microscope examination. Both inhibitory and binding studies indicate that antibodies against α2β1 inhibit not only platelet agglutination induced by bilinexin, but also bilinexin binding to platelets. VM16d, a monoclonal anti-GPIbα antibody, completely inhibits platelet agglutination induced by bilinexin, and polyclonal antibodies against GPIbα prevent its binding to platelets. However, neither convulxin, polyclonal anti-GPVI antibodies, nor GPIIb/IIIa inhibitors affect its binding to and agglutination of platelets. Bilinexin neither activates GPIIb/IIIa integrin on platelets nor induces tyrosine phosphorylation of platelet proteins, nor increases intracellular Ca2+ in platelets. Like alboaggregin B, bilinexin agglutinates platelets, which makes it a good tool to investigate the differences in mechanism between snake C-type lectins causing platelet agglutination and those that induce full activation.


2017 ◽  
Vol 37 (1) ◽  
pp. 31
Author(s):  
Fitria Fitria ◽  
Nanik Rahmani ◽  
Sri Pujiyanto ◽  
Budi Raharjo ◽  
Yopi Yopi

Enzyme xylanase (EC 3.2.1.8) is widely used in various industrial  fields for the hydrolysis of xylan (hemicellulose) into xylooligosaccharide and xylose. The aims of this study were to  conduct partial purification and characterization of xylanase from marine Bacillus safencis strain LBF P20 and to obtain the  xylooligosaccharide types from xylan hydrolysis by this enzyme.  Based on this research, the optimum time for enzyme production  occurred at 96 hours with the enzyme activity of 6.275 U/mL and  enzyme specific activity of 5.093 U/mg. The specific activities were  obtained from precipitation by amicon® ultra-15 centrifugal filter devices, gel filtration chromatography and anion exchange chromatography that were increased by 15.07, 34.7, and 96.0  U/mg. The results showed that the highest activity at pH 7, temperature of 60 °C, and stable at 4 °C. Type of  xylooligosaccharide produced by this study were xylohexoses, xylotriose, and xylobiose. SDS-PAGE analysis and zimogram  showed that the molecular weight of xylanase protein were about  25 kDa. ABSTRAKEnzim xilanase (EC 3.2.1.8) digunakan dalam hidrolisis xilan  (hemiselulosa) menjadi xilooligosakarida dan xilosa. Penelitian  ini bertujuan untuk melakukan purifikasi parsial dan karakterisasi xilanase dari bakteri laut Bacillus safencis strain LBF P20 serta uji  hidrolisis untuk mengetahui jenis xilooligosakarida yang  dihasilkan oleh enzim tersebut. Berdasarkan hasil penelitian, waktu optimum untuk produksi enzim terjadi pada jam ke 96  dengan aktivitas enzim sebesar 6,275 U/mL dan aktivitas spesifik enzim sebesar 5,093 (U/mg). Aktivitas spesifik enzim hasil  pemekatan dengan amicon® ultra-15 centrifugal filter devices,  kromatografi filtrasi gel dan kromatografi penukar anion  mengalami peningkatan berturut-turut sebesar 15,1; 34,7 dan96,0 U/mg. Hasil karakterisasi menunjukkan aktivitas  tertinggi pada pH 7, suhu 60 °C dan stabil pada suhu 4 °C. Analisis SDS-PAGE dan zimogram menunjukkan berat molekul protein xilanase berkisar 25 kDa. Jenis gula reduksi yang  dihasilkan yaitu xiloheksosa, xilotriosa, dan xilobiosa.


1991 ◽  
Vol 278 (2) ◽  
pp. 329-333 ◽  
Author(s):  
L Huang ◽  
T H Hseu ◽  
T T Wey

Trichoderma koningii G-39 produced xylanases in submerged culture using oat spelt xylan or crystalline cellulose, Avicel, as the sole carbon source. A low-Mr xylanase was purified from the culture filtrate by ion-exchange chromatography on SP-Trisacryl-M and gel filtration on Fractogel TSK HW-50F. It was homogeneous on SDS/PAGE and isoelectric focusing. A typical procedure provided about 11-fold purification with 4.5% protein yield and 50% activity recovery. The purified enzyme has an Mr value of about 21,500 and a pI of 8.9. Its specific activity was 6100 units/mg of protein, with optimal activity towards 0.5% xylan at about pH 5.5 and 60 degrees C. The purified enzyme had no activity against CM-cellulose with a degree of substitution of 0.63. It also showed no beta-xylosidase activity. The Km and Vmax. values, as determined with the soluble fraction of oat spelt xylan as substrate, were 0.70 mg/ml and 1.85 x 10(6) mumol/min per mg of enzyme respectively. Hg2+ (1 mM) and SDS (10 mM) completely inhibited xylanase activity, whereas Ca2+ showed no significant effect on the enzyme activity at 1 mM, but gave 80% inhibition at 10 mM. The enzyme contained about 4.4% carbohydrate and showed an immunological relationship to a cellobiohydrolase from the same fungal strain.


Parasitology ◽  
2003 ◽  
Vol 126 (2) ◽  
pp. 155-163 ◽  
Author(s):  
A. SEIXAS ◽  
P. C. DOS SANTOS ◽  
F. F. VELLOSO ◽  
I. DA SILVA VAZ ◽  
A. MASUDA ◽  
...  

Here we describe the purification and characterization of a vitellin (VT) degrading cysteine endopeptidase (VTDCE) from eggs of the hard tick Boophilus microplus. A homogeneous enzyme preparation was obtained by chromatographic fractionation on ion-exchange and gel filtration columns and an autolysis step. This step consisted of incubation of a semipurified enzyme (after the first ion-exchange chromatography) at pH 4·0 that dissociated the enzyme from VT, to which VTDCE is naturally tightly associated. The enzyme purity was confirmed by capillary and native gel electrophoresis, and SDS–PAGE suggested the enzyme is a dimer of 17 and 22 kDa. VTDCE was active upon several synthetic substrates, with a preference for a hydrophobic or a basic residue in P1, and a hydrophobic residue in P2. VTDCE also hydrolysed haemoglobin, albumin, gelatin and vitellin. VTDCE is inactive in the absence of DTT and was totally inhibited by E-64, indicating it is a cysteine endopeptidase. Our results suggest that VTDCE is a major enzyme involved in yolk processing during B. microplus embryogenesis.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
S. Nagaraju ◽  
K. Kemparaju

India is a habitat for nearly one thousand four hundred forty-seven species of spiders under three hundred and sixty-five genera and sixty families. Our initial survey on toxic bite by spider revealed severe edema, itching, acute pain, and hemorrhage following tissue necrosis, which are the general symptoms of envenomation, but there are no reports of mortality. Significantly, Hippasa partita spider, commonly called “funnel web spider,” which is endemic in hilly regions of the Western Ghats is responsible for envenomation. In this study, a nonenzymatic neurotoxin has been purified from H. partita venom gland extract. Gel filtration and ion exchange chromatography were used to purify the toxin into homogeneity as shown by SDS-PAGE, RP-HPLC, and MALDI-TOF. Neurotoxin is devoid of enzymatic activities but causes intense neurotoxic symptoms. Neurotoxin is found to inhibit the twitch response of sciatic nerve gastrocnemius muscle preparation and is found to be postsynaptic in action. Neurotoxin is devoid of coagulant activity, edema, and hemorrhage and is nonlethal to mice (up to 5 mg/kg body weight). In conclusion, a neurotoxin, which is a principle agent in whole venom responsible for induced neurotoxic symptoms, has been purified and characterized.


2013 ◽  
Vol 773 ◽  
pp. 336-341 ◽  
Author(s):  
Wen Ge Yu ◽  
Bei Bei Zhang ◽  
Yong Jian Shen ◽  
Ying Li ◽  
Yong Bin Tian ◽  
...  

In this paper, the superoxide dismutase fromMartianus dermestoidesis purified by the following methods: heat treatment, polyethylene concentration, Sephadex G-75 gel filtration, and DEAE-Sepharose FF ion exchange chromatography. The result shows that the purification multiple is 3.86, the activation yield is 21.89% and the specific activation of the enzyme is 447.6 U/mg. The purified SOD appears to be a sole protein on SDS-PAGE and the molecular weight is estimated to be 40.58 kDa. H2O2can obviously inhibit the enzyme activation and CHCl3-CH3CH2OH only demonstrates basically no inhibitory effect. The type of the dermestoides SOD might be Cu/Zn-SOD. After purification, some enzymatic characterizations of the SOD are studied. The optimum reaction temperature of purified SOD is 50°C. The optimum reaction pH value of purification is 6. The dermestoide SOD has a preferable stability below 50°C and at pH values between 5-8.


Sign in / Sign up

Export Citation Format

Share Document