scholarly journals Purification and Characterization of an X-Prolyl-Dipeptidyl Peptidase from Lactobacillus sakei

2001 ◽  
Vol 67 (4) ◽  
pp. 1815-1820 ◽  
Author(s):  
Yolanda Sanz ◽  
Fidel Toldrá
Keyword(s):  
Proteinase Inhibitors ◽  
Divalent Cations ◽  
Gel Filtration ◽  
Serine Proteinase ◽  
Anion Exchange Chromatography ◽  
Dipeptidyl Peptidase ◽  
Exchange Chromatography ◽  
Lactobacillus Sakei ◽  
N Terminus ◽  
Hydrolysis Of

ABSTRACT An X-prolyl-dipeptidyl peptidase has been purified fromLactobacillus sakei by ammonium sulfate fractionation and five chromatographic steps, which included hydrophobic interaction, anion-exchange chromatography, and gel filtration chromatography. This procedure resulted in a recovery yield of 7% and an increase in specificity of 737-fold. The enzyme appeared to be a dimer with a subunit molecular mass of approximately 88 kDa. Optimal activity was shown at pH 7.5 and 55°C. The enzyme was inhibited by serine proteinase inhibitors and several divalent cations (Cu2+, Hg2+, and Zn2+). The enzyme almost exclusively hydrolyzed X-Pro from the N terminus of each peptide as well as fluorescent and colorimetric substrates; it also hydrolyzed X-Ala at the N terminus, albeit at lower rates. Km s for Gly-Pro- and Lys-Ala-7-amido-4-methylcoumarin were 29 and 88 μM, respectively; those for Gly-Pro- and Ala-Pro-p-nitroanilide were 192 and 50 μM, respectively. Among peptides, β-casomorphin 1-3 was hydrolyzed at the highest rates, while the relative hydrolysis of the other tested peptides was only 1 to 12%. The potential role of the purified enzyme in the proteolytic pathway by catalyzing the hydrolysis of peptide bonds involving proline is discussed.

scholarly journals Purification and Characterization of an Arginine Aminopeptidase from Lactobacillus sakei

2002 ◽  
Vol 68 (4) ◽  
pp. 1980-1987 ◽  
Author(s):  
Yolanda Sanz ◽  
Fidel Toldrá
Keyword(s):  
Specific Activity ◽  
Divalent Cations ◽  
Gel Filtration ◽  
Sulfhydryl Group ◽  
Fold Increase ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Lactobacillus Sakei ◽  
C Terminus ◽  
Arginine Aminopeptidase

ABSTRACT An arginine aminopeptidase (EC 3.4.11.6) that exclusively hydrolyzes basic amino acids from the amino (N) termini of peptide substrates has been purified from Lactobacillus sakei. The purification procedure consisted of ammonium sulfate fractionation and three chromatographic steps, which included hydrophobic interaction, gel filtration, and anion-exchange chromatography. This procedure resulted in a recovery rate of 4.2% and a 500-fold increase in specific activity. The aminopeptidase appeared to be a trimeric enzyme with a molecular mass of 180 kDa. The activity was optimal at pH 5.0 and 37°C. The enzyme was inhibited by sulfhydryl group reagents and several divalent cations (Cu2+, Hg2+, and Zn2+) but was activated by reducing agents, metal-chelating agents, and sodium chloride. The enzyme showed a preference for arginine at the N termini of aminoacyl derivatives and peptides. The Km values for Arg-7-amido-4-methylcoumarin (AMC) and Lys-AMC were 15.9 and 26.0 μM, respectively. The nature of the amino acid residue at the C terminus of dipeptides has an effect on hydrolysis rates. The activity was maximal toward dipeptides with Arg, Lys, or Ala as the C-terminal residue. The properties of the purified enzyme, its potential function in the release of arginine, and its further metabolism are discussed because, as a whole, it could constitute a survival mechanism for L. sakei in the meat environment.

scholarly journals A high-molecular-mass neutral endopeptidase-24.5 from human lung

1987 ◽  
Vol 241 (1) ◽  
pp. 129-135 ◽  
Author(s):  
R Zolfaghari ◽  
C R Baker ◽  
P C Canizaro ◽  
A Amirgholami ◽  
F J Bĕhal
Keyword(s):  
Metal Ions ◽  
Human Lung ◽  
Proteinase Inhibitors ◽  
Gel Filtration ◽  
Serine Proteinase ◽  
Neutral Endopeptidase ◽  
Exchange Chromatography ◽  
Polyacrylamide Gel ◽  
Ph Optimum ◽  
Apparent Homogeneity

A high-Mr neutral endopeptidase-24.5 (NE) that cleaved bradykinin at the Phe5-Ser6 bond was purified to apparent homogeneity from human lung by (NH4)2SO4 fractionation, ion-exchange chromatography and gel filtration. The final enzyme preparation produced a single enzymically active protein band after electrophoresis on a 5% polyacrylamide gel. Human lung NE had an Mr of 650,000 under non-denaturing conditions, but after denaturation and electrophoresis on an SDS/polyacrylamide gel NE dissociated into several lower-Mr components (Mr 21,000-32,000) and into two minor components (Mr approx. 66,000). The enzyme activity was routinely assayed with the artificial substrate Z-Gly-Gly-Leu-Nan (where Z- and -Nan represent benzyloxycarbonyl- and p-nitroanilide respectively). NE activity was enhanced slightly by reducing agents, greatly diminished by thiol-group inhibitors and unchanged by serine-proteinase inhibitors. Human lung NE was inhibited by the univalent cations Na+ and K+. No metal ions were essential for activity, but the heavy-metal ions Cu2+, Hg2+ and Zn2+ were potent inhibitors. With the substrate Z-Gly-Gly-Leu-Nan a broad pH optimum from pH 7.0 to pH 7.6 was observed, and a Michaelis constant value of 1.0 mM was obtained. When Z-Gly-Gly-Leu-Nap (where -Nap represents 2-naphthylamide) was substituted for the above substrate, no NE-catalysed hydrolysis occurred, but Z-Leu-Leu-Glu-Nap was readily hydrolysed by NE. In addition, NE hydrolysed Z-Gly-Gly-Arg-Nap rapidly, but at pH 9.8 rather than in the neutral range. Although human lung NE was stimulated by SDS, the extent of stimulation was not appreciable as compared with the extent of SDS stimulation of NE from other sources.

scholarly journals Pemurnian Parsial dan Karakterisasi Enzim Xilanase dari Bakteri Laut Bacillus safencis strain LBF P20 Asal Pulau Pari Jakarta

2017 ◽  
Vol 37 (1) ◽  
pp. 31
Author(s):  
Fitria Fitria ◽  
Nanik Rahmani ◽  
Sri Pujiyanto ◽  
Budi Raharjo ◽  
Yopi Yopi
Keyword(s):  
Specific Activity ◽  
Gel Filtration ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Partial Purification ◽  
Centrifugal Filter ◽  
Sds Page ◽  
Enzyme Specific Activity ◽  
Hydrolysis Of

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.

scholarly journals The Modified β-Ketoadipate Pathway in Rhodococcus rhodochrous N75: Enzymology of 3-Methylmuconolactone Metabolism

1998 ◽  
Vol 180 (24) ◽  
pp. 6668-6673 ◽  
Author(s):  
Chang-Jun Cha ◽  
Ronald B. Cain ◽  
Neil C. Bruce
Keyword(s):  
Ammonium Sulfate ◽  
Gel Filtration ◽  
Sole Source ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Rhodococcus Rhodochrous ◽  
Natural Substrate ◽  
Ph Optimum ◽  
A Subunit ◽  
Hydrolysis Of

ABSTRACT Rhodococcus rhodochrous N75 is able to metabolize 4-methylcatechol via a modified β-ketoadipate pathway. This organism has been shown to activate 3-methylmuconolactone by the addition of coenzyme A (CoA) prior to hydrolysis of the butenolide ring. A lactone-CoA synthetase is induced by growth of R. rhodochrous N75 on p-toluate as a sole source of carbon. The enzyme has been purified 221-fold by ammonium sulfate fractionation, hydrophobic chromatography, gel filtration, and anion-exchange chromatography. The enzyme, termed 3-methylmuconolactone-CoA synthetase, has a pH optimum of 8.0, a native M r of 128,000, and a subunitM r of 62,000, suggesting that the enzyme is homodimeric. The enzyme is very specific for its 3-methylmuconolactone substrate and displays little or no activity with other monoene and diene lactone analogues. Equimolar amounts of these lactone analogues brought about less than 30% (most brought about less than 15%) inhibition of the CoA synthetase reaction with its natural substrate.

scholarly journals Characterization of a chelator-resistant proteinase from Thermus strain Rt4A2

1993 ◽  
Vol 295 (2) ◽  
pp. 463-469 ◽  
Author(s):  
S A Freeman ◽  
K Peek ◽  
M Prescott ◽  
R Daniel
Keyword(s):  
Specific Activity ◽  
Sequence Similarity ◽  
Substrate Inhibition ◽  
Gel Filtration ◽  
Serine Proteinase ◽  
Fold Increase ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Ph Optimum ◽  
High Sequence Similarity

The Thermus isolate Rt4A2 was found to produce an extracellular chelator-resistant proteinase. The proteinase was purified to homogeneity by (NH4)2SO4 precipitation, cation-exchange chromatography, gel-filtration chromatography, and weak anion-exchange chromatography. The Rt4A2 proteinase was found to have properties typical of an alkaline serine proteinase. It had a pH optimum of 9.0 and was specifically inhibited by phenylmethanesulphonyl fluoride. Its isoelectric point was greater than 10.25. Its molecular-mass was 31.6 kDa as determined by SDS/PAGE. N-terminal sequencing has shown it to have high sequence similarity with other serine proteinases from Thermus species. The proteinase hydrolysed a number of substrates including fibrin, casein, haemoglobin, collagen, albumin and the synthetic chromogenic peptide substrate Suc-Ala-Ala-Pro-Phe-NH-Np. The specific activity of the purified proteinase using azocasein as substrate was 313 units/mg. Substrate inhibition was observed above an azocasein concentration of 0.05% (w/v). Esterase activity was directed mainly towards those substrates containing the aliphatic or aromatic residues of alanine, glycine, tryptophan, tyrosine and phenylalanine. Thermostability half-lives of greater than 7 days at 70 degrees C, 43 h at 80 degrees C and 90 min at 90 degrees C were found in the presence of 5 mM CaCl2. At 90 degrees C increasing the CaCl2 concentration 100-fold (0.5 mM to 50 mM) caused a 4.3-fold increase in the half-life of the enzyme from 30 to 130 min. Half-lives of 19.4 min at 100 degrees C and 4.4 min at 105 degrees C were found in the presence of 50 mM CaCl2. The metal chelators EGTA and EDTA reduced the stability at higher temperatures but had no effect on the activity of the proteinase. Activity was not stimulated by common metal activators such as Ca2+, Mg2+ and Zn2+.

scholarly journals Purification and Characterization of an Alkaline Phosphatase Induced by Phosphorus Starvation in Common Bean (Phaseolus vulgaris L.) Roots

2017 ◽  
Vol 56 (1) ◽  
Author(s):  
Lorena Morales ◽  
Natalia Gutiérrez ◽  
Vanessa Maya ◽  
Carmen Parra ◽  
Eleazar Martínez-Barajas ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Divalent Cations ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Phosphate Deficiency ◽  
Ionic Exchange ◽  
Sds Page ◽  
Hydrolysis Of

Two phosphatase isoforms from roots of the common bean (<em>Phaseolus vulgaris</em> L.) showed an increase in activity in response to phosphate deficiency. One of them (APIII) was chosen for further purification through ionic exchange chromatography and preparative electrophoresis. The estimated molecular mass of APIII was 35 kDa by both SDS-PAGE and gel filtration analyses, suggesting a monomeric form of the active enzyme. The phosphatase was classified as an alkaline phosphatase based on the requirement of pH 8 for optimum catalysis. It not only exhibited broad substrate specificity, with the most activity against pyrophosphate, but also effectively catalyzed the hydrolysis of polyphosphate, glucose-1-phosphate and phosphoenolpyruvate. Activity was completely inhibited by molybdate, vanadate and phosphate but was only partially inhibited by fluoride. Although divalent cations were not essential for the pyrophosphatase activity of this enzyme, the hydrolysis of pyrophosphate increased substantially in the presence of Mg<sup>2+</sup>.

Naphthylamidases of Sarcina lutea

1971 ◽  
Vol 17 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Francis J. Behal ◽  
Rita T. Carter
Keyword(s):  
Divalent Cations ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Substrate Specificities ◽  
Molecular Weights ◽  
Hydrolysis Of

The naphthylamidase isozyme complement of Sarcina lutea was studied. Gel filtration yielded two fractions, Sephadex I and Sephadex II. Sephadex I contained one enzyme generally resembling leucineaminopeptidase. Sephadex II, upon ion exchange chromatography, yielded three isozymes, A, B, and C. These three were characterized with respect to molecular weight, substrate specificities, and effects of hydrogen ion concentration, EDTA, and divalent cation on reaction velocity. The molecular weights are 8.0 × 104, 8.2 × 104, and 9.0 × 104 respectively. Isozymes A and B are neutral naphthylamidases and preferentially catalyze the hydrolysis of alanine-β-naphthylamide (βNA), whereas isozyme C is a basic naphthylamidase and preferentially catalyzes the hydrolysis of lysine and arginine-βNA. The pH optima for the isozymes are 7.6, 7.6, and 6.7, respectively. All of the isozymes are sensitive to the effects of EDTA. Divalent cations activate the enzymes and reverse inhibition caused by EDTA.

Synthetic 1-thio-β-D-glucosiduronic acids as substrates for rat-liver β-glucuronidase

1970 ◽  
Vol 48 (7) ◽  
pp. 799-804 ◽  
Author(s):  
C. Hétu ◽  
R. Gianetto
Keyword(s):  
Rat Liver ◽  
Molecular Sieve ◽  
Enzyme Preparation ◽  
Gel Filtration ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Ph Optimum ◽  
Filtration Step ◽  
Hydrolysis Of ◽  
Menten Constant

The hydrolysis of 1-thio-β-D-glucosiduronic acids by rat liver was studied using synthetic phenyl 1-thio-β-D-glucosiduronic acid, sodium (2-benzothiazolyl 1-thio-β- D-glucosid)uronate, and sodium (p-nitrophenyl 1-thio-β-D-glucosid)uronate. It was found that rat liver preparations can hydrolyze the β-D-glucuronides of 2-benzothiazolethiol and p-nitrothiophenol but not the β-D-glucuronide of thiophenol.Partial purification of the enzyme from a lysosomal preparation using ammonium sulfate fractionation, gel filtration on a molecular sieve, and anion-exchange chromatography showed that β-glucuronidase (EC 3.2.1.31) is the enzyme responsible for the hydrolysis of these thioglucuronides. The pH optimum and Michaelis–Menten constant (Km) were determined for both substrates using an enzyme preparation obtained after the gel filtration step. The glucuronide of 2-benzothiazolethiol was found to be almost as good a substrate as that of phenolphthalein for rat-liver β-glucuronidase, while the glucuronide of p-nitrothiophenol is hydrolyzed at a much slower rate. Possible explanations of the fact that β-glucuronidase hydrolyzes only certain thioglucuronides are suggested.

scholarly journals Chemical identity of tryptensin with angiotensin

1980 ◽  
Vol 187 (3) ◽  
pp. 647-653 ◽  
Author(s):  
K Arakawa ◽  
M Yuki ◽  
M Ikeda
Keyword(s):  
Amino Acid ◽  
Thin Layer ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Cation Exchange Chromatography ◽  
Human Plasma Protein ◽  
Plasma Protein Fraction ◽  
Layer Chromatography

Tryptensin, a vasopressor substance generated from human plasma protein fraction IV-4 by trypsin, has been isolated and the amino acid composition analysed. The procedures used for the isolation were: (a) adsorption of the formed tryptensin on Dowex 50W (X2; NH4+ form); (b) gel filtration through Sephadex G-25; (c) cation-exchange chromatography on CM-cellulose; (d) anion-exchange chromatography on DEAE-cellulose; (e) re-chromatography on CM-cellulose; (f) gel filtration on Bio-Gel P-2; (g) partition chromatography on high-pressure liquid chromatography. The homogeneity of the isolated tryptensin was confirmed by thin-layer chromatography and thin-layer electrophoresis. The amino acid analysis of the hydrolysate suggested the following proportional composition: Asp, 1; Val, 1; Ile, 1; Tyr, 1; Phe, 1; His, 1; Arg, 1; Pro, 1. This composition is identical with that of human angiotensin.

Sign in / Sign up

Export Citation Format

Share Document