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Radosavljević J, Stanić-Vučinić D, Stojadinović M, Radomirović M, Simović A, Radibratović M, Veličković TĆ. Application of Ion Exchange and Adsorption Techniques for Separation of
Whey Proteins from Bovine Milk. CURR ANAL CHEM 2022. [DOI: 10.2174/1573411017666210108092338] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
The world production of whey was estimated to be more than 200 million tons per year.
Although whey is an important source of proteins with high nutritional value and biotechnological importance, it is still
considered as a by-product of the dairy industry with low economic value due to low industrial exploitation. There are
several challenges in the separation of whey proteins: low concentration, the complexity of the material and similar
properties (pI, molecular mass) of some proteins.
Methods:
A narrative review of all the relevant papers on the present methodologies based on ion-exchange and
adsorption principles for isolation of whey proteins, known to the authors, was conducted.
Results:
Traditional ion-exchange techniques are widely used for the separation and purification of the bovine whey
proteins. These methodologies, based on the anion or cation chromatographic procedures, as well as combination of
aforementioned techniques are still preferential methods for the isolation of the whey proteins on the laboratory scale.
However, more recent research on ion exchange membranes for this purpose has been introduced, with promising
potential to be applied on the pilot industrial scale. Newly developed methodologies based either on the ion-exchange
separation (for example: simulated moving bed chromatography, expanded bed adsorption, magnetic ion exchangers, etc.)
or adsorption (for example: adsorption on hydroxyapatite or activated carbon, or molecular imprinting) are promising
approaches for scaling up of the whey proteins’ purification processes.
Conclusion:
Many procedures based on ion exchange are successfully implemented for separation and purification of
whey proteins, providing protein preparations of moderate-to-high yield and satisfactory purity. However, the authors
anticipate further development of adsorption-based methodologies for separation of whey proteins by targeting the
differences in proteins’ structures rather than targeting the differences in molecular masses and pI. The complex
composite multilayered matrices, including also inorganic components, are promising materials for simultaneous
exploiting of the differences in the masses, pI and structures of whey proteins for the separation.
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Affiliation(s)
- Jelena Radosavljević
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
| | - Dragana Stanić-Vučinić
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
| | - Marija Stojadinović
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
| | - Mirjana Radomirović
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
| | - Ana Simović
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
| | - Milica Radibratović
- Center for Chemistry, University of Belgrade - Institute of Chemistry, Technology and Metallurgy, Njegoševa 12, 11000 Belgrade,Serbia
| | - Tanja Ćirković Veličković
- Department of Biochemistry & Centre of Excellence for Molecular Food Sciences, Faculty of Chemistry, University of Belgrade, Studentski trg 12‑16, 11000 Belgrade,Serbia
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2
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Optimization of Lactoperoxidase and Lactoferrin Separation on an Ion-Exchange Chromatography Step. SEPARATIONS 2017. [DOI: 10.3390/separations4020010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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3
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Isolation of lactoperoxidase using different cation exchange resins by batch and column procedures. J DAIRY RES 2010; 77:357-67. [DOI: 10.1017/s002202991000018x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Lactoperoxidase (LP) was isolated from whey protein by cation-exchange using Carboxymethyl resin (CM-25C) and Sulphopropyl Toyopearl resin (SP-650C). Both batch and column procedures were employed and the adsorption capacities and extraction efficiencies were compared. The resin bed volume to whey volume ratios were 0·96:1·0 for CM-25C and ⩽0·64:1·0 for SP-650 indicating higher adsorption capacity of SP-650 compared with CM-25C. The effluent LP activity depended on both the enzyme activity in the whey and the amount of whey loaded on the column within the saturation limits of the resin. The percentage recovery was high below the saturation point and fell off rapidly with over-saturation. While effective recovery was achieved with column extraction procedures, the recovery was poor in batch procedures. The whey-resin contact time had little impact on the enzyme adsorption. SDS PAGE and HPLC analyses were also carried out, the purity was examined and the proteins characterised in terms of molecular weights. Reversed phase HPLC provided clear distinction of the LP and lactoferrin (LF) peaks. The enzyme purity was higher in column effluents compared with batch effluents, judged on the basis of the clarity of the gel bands and the resolved peaks in HPLC chromatograms.
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Ozdemir H, Aygul I, Küfrevioglu OI. Purification of lactoperoxidase from bovine milk and investigation of the kinetic properties. Prep Biochem Biotechnol 2001; 31:125-34. [PMID: 11426700 DOI: 10.1081/pb-100103378] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Lactoperoxidase (LPO) was purified from bovine milk using Amberlite CG 50 H+ resin, CM Sephadex C-50 ion-exchange chromatography, and Sephadex G-100 gel filtration chromatography. During the purification steps, the activity of enzyme was measured using 2,2'-azino-bis (3-ethylbenzthiazoline-6 sulfonic acid) diamonium salt (ABTS) as a chromogenic substrate at pH 6. Optimum pH and optimum temperature values for LPO were determined for ABTS, p-phenylendiamine, catechol, epinephrine, and pyrogallol as substrates, and then Km and Vmax values for the same substrate were obtained by means of Lineweaver-Burk graphics. The purification degree of the enzyme was controlled by SDS-PAGE and Rz (A412/A280) values. Km values, at optimum pH and 20 degrees C, were 0.197 mM, 0.063 mM, 0.64 mM, 25.2 mM, and 63.95 mM for p-phenylendiamine, ABTS, epinephrine, pyrogallol, and catechol, respectively. Vmax values, at optimum pH and 20 degrees C, were 3.5x10(-5) EU/mL, 4.0x10(-5) EU/mL, 5.8x10(-4) EU/mL, 8.4x10(-4) EU/mL, and 1.01x10(-3) EU/mL for the same substrates, respectively. p-Phenylendiamine was first found as a new substrate for LPO.
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Affiliation(s)
- H Ozdemir
- Department of Biochemistry, Faculty of Science and Arts, Ataturk University, Erzurum, Turkey
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6
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Wolf SM, Ferrari RP, Traversa S, Biemann K. Determination of the carbohydrate composition and the disulfide bond linkages of bovine lactoperoxidase by mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2000; 35:210-217. [PMID: 10679983 DOI: 10.1002/(sici)1096-9888(200002)35:2<210::aid-jms931>3.0.co;2-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The extent and distribution of N-glycosylation and the nature of most of the disulfide bond linkages were determined for bovine lactoperoxidase through proteolytic and glycolytic digestions combined with matrix-assisted laser desorption/ionization mass spectrometric analysis. In addition, 98% of the primary sequence of the protein was confirmed. All five of the asparagines present in sequons were found to be glycosylated, predominantly by high mannose and complex structures. Six disulfide bonds were assigned, including Cys 32-Cys 45, Cys 146-Cys 156, Cys 150-Cys 174, Cys 254-Cys 265, Cys 473-Cys 530 and Cys 571-Cys 596.
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Affiliation(s)
- S M Wolf
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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7
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Sato K, Hasumi H, Tsukidate A, Sakurada J, Nakamura S, Hosoya T. Effects of mixed solvents on three elementary steps in the reactions of horseradish peroxidase and lactoperoxidase. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1253:94-102. [PMID: 7492606 DOI: 10.1016/0167-4838(95)00144-j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effects of methanol, acetone, and ethylene glycol (up to 50% v/v) on elementary steps in the reactions of horseradish peroxidase (HRP) and lactoperoxidase (LPO) were studied by means of the stopped-flow method and the difference spectrum. The rate constant (k3,app) of the oxidation reaction of p-cresol with HRP compound II was remarkably reduced in the presence of organic solvents (to 2.3%, 1.8% and 9.4% of the original value in the presence of 50% (v/v) of methanol, acetone and ethylene glycol, respectively), then to a lesser degree were decreased the rate of the oxidation reaction with LPO compound II, and the rate of the oxidation reaction with HRP compound I. These reductions in the reaction rates were not due to competitive inhibition of the solvents, but considered to be related to the degree of exposure of the electron transfer route to the medium. While the rate constant of compound I formation (k1,app) was moderately affected by organic solvents in the case of HRP, the reaction rate with LPO was scarcely affected by organic solvents, being in harmony with the compact heme crevice which probably hampers penetration of solvent molecules. The rate constant (k2,i,app) of the oxidation reaction of an iodide ion by HRP compound I was also hardly affected by the solvents. On the basis of these facts, the mechanism of electron transfer from donors to compound I and compound II is discussed.
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Affiliation(s)
- K Sato
- Faculty of Pharmaceutical Sciences, Chiba University, Japan
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8
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Chang CS, Sinclair R, Khalid S, Yamazaki I, Nakamura S, Powers L. An extended X-ray absorption fine structure investigation of the structure of the active site of lactoperoxidase. Biochemistry 1993; 32:2780-6. [PMID: 8457545 DOI: 10.1021/bi00062a007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Native lactoperoxidase, compound III, and the reduced forms (at pH 6 and 9) were studied using X-ray absorption spectroscopy (XAS). Native lactoperoxidase has four pyrrole nitrogen ligands at an average distance of 2.04 +/- 0.01 A, a proximal ligand at 1.91 +/- 0.02 A, and a sixth (distal) ligand at 2.16 +/- 0.03 A. Lactoperoxidase native enzyme has a first coordination shell structure that is similar to that of native lignin peroxidase [Sinclair, R., Yamazaki, I., Bumpus, J., Brock, B., Chang, C.-S., Albo, A., & Powers, L. (1992) Biochemistry 31, 4892-4900] and different from that of horseradish peroxidase [Chance, B., Powers, L., Ching, Y., Poulos, T., Schonbaum, G., Yamazaki, I., & Paul, K. (1984) Arch. Biochem. Biophys. 235, 596-611]. Similarly, lactoperoxidase compound III resembles lignin peroxidase compound III. The five-coordinated ferrous form was stable at pH 9, but at pH 6 it was rapidly converted to the six-coordinated form with a distal ligand at 2.18 +/- 0.03 A. No evidence typical of changes in spin state was obtained at the different pH values.
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Affiliation(s)
- C S Chang
- National Center for the Design of Molecular Function, Utah State University, Logan 84322-4630
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9
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Farhangrazi ZS, Sinclair R, Yamazaki I, Powers LS. Haloperoxidase activity of Phanerochaete chrysosporium lignin peroxidases H2 and H8. Biochemistry 1992; 31:10763-8. [PMID: 1420193 DOI: 10.1021/bi00159a017] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Monochlorodimedone (MCD), commonly used as a halogen acceptor for haloperoxidase assays, was oxidized by hydrogen peroxide in the presence of lignin peroxidase isoenzymes H2 and H8. When oxidized, it produced a weak absorption band with an intensity that varied with pH. This absorbance was used as a simple method for the product analysis because it disappeared when MCD was brominated or chlorinated. We assessed the activity of the lignin peroxidases for oxidation of bromide by measuring the bromination of MCD, the formation of tribromide, the bromide-mediated oxidation of glutathione, and the bromide-mediated catalase-like activity. We analyzed the reaction products of MCD and the halide-mediated oxidation of glutathione when bromide was replaced by chloride. These enzymes demonstrated no significant activity for oxidation of chloride. Unlike other peroxidases, the lignin peroxidases exhibited similar pH-activity curves for the iodide and bromide oxidations. The optimum pH for activity was about 2.5. Surprisingly, this pH dependence of lignin peroxidase activity for the halides was nearly the same in the reactions with hydrogen donors, such as hydroquinone and guaiacol. The results suggested that protonation of the enzymes with pKa approximately 3.2 is necessary for the catalytic function of lignin peroxidases, irrespective of whether the substrates are electron or hydrogen donors. These unique reaction profiles of lignin peroxidases are compared to those of other peroxidases, such as lactoperoxidase, bromoperoxidase, chloroperoxidase, and horseradish peroxidase. Isozyme H2 was more active than isozyme H8, but isozyme H8 was more stable at very acidic pH.
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Affiliation(s)
- Z S Farhangrazi
- National Center for the Design of Molecular Function, Utah State University, Logan 84322-4630
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10
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De PK. Tissue distribution of constitutive and induced soluble peroxidase in rat. Purification and characterization from lacrimal gland. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 206:59-67. [PMID: 1587283 DOI: 10.1111/j.1432-1033.1992.tb16901.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A thorough search for a soluble peroxidase in 31 different tissues of rat indicated the presence of a constitutive activity only in lacrimal, preputial and submaxillary gland. An induced soluble peroxidase activity was also detected in the lactating mammary gland and in the estrogen-induced uterine secretory fluid. The lacrimal gland was the richest source of the enzyme. No peroxidase activity was detected in the lactating mammary gland of mouse and hamster nor in the preputial gland of mouse and uterine fluid of hamster. The three constitutive and two induced soluble peroxidases of rat had a native molecular mass of 73 kDa by gel filtration and they showed a similar mobility in native PAGE. Lactoperoxidase of cow's milk and solubilized rat membrane-bound peroxidases of uterus, intestine and bone marrow showed in native PAGE a mobility which was distinctly different from that of rat soluble peroxidases. As the lacrimal gland of rat was the richest source of soluble peroxidase, the enzyme was purified from this gland to apparent homogeneity; SDS/PAGE then showed a single band of molecular mass 75 kDa which was similar to that obtained by gel filtration. Peroxidase also purified from preputial and submaxillary gland, as well as commercial lactoperoxidase, had a similar molecular mass on SDS/PAGE to purified lacrimal peroxidase. The visible spectrum of lacrimal peroxidase was similar to that of lactoperoxidase but different from membrane-bound peroxidase of rat neutrophils. On isoelectric focussing, purified lacrimal peroxidase resolved into about 14 multiple forms spanning a pI range of 6.5-3.5 while lactoperoxidase focussed at the cathode. Evidence presented suggests that the multiple forms are possibly due to differences in glycosylation. Immunodiffusion, immunoprecipitation and Western blot using antilacrimal peroxidase serum showed a similar interacting species for all five soluble peroxidases of rat while membrane-bound peroxidases showed no interaction. Although in immunodiffusion, the antiserum failed to cross-react with lactoperoxidase it did interact with lactoperoxidase on Western blot. The results indicate that the various constitutive and induced soluble peroxidases of rat tissues are similar to lacrimal peroxidase but are distinctly different from the known membrane-bound peroxidases of rat. However the lacrimal peroxidase shows both similarities as well as dissimilarities with bovine lactoperoxidase. This soluble peroxidase system of rat could be useful to study tissue-specific regulation of gene expression at the molecular level.
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Affiliation(s)
- P K De
- Centre for Cellular and Molecular Biology, Hyderabad, India
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11
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Cals MM, Mailliart P, Brignon G, Anglade P, Dumas BR. Primary structure of bovine lactoperoxidase, a fourth member of a mammalian heme peroxidase family. EUROPEAN JOURNAL OF BIOCHEMISTRY 1991; 198:733-9. [PMID: 2050150 DOI: 10.1111/j.1432-1033.1991.tb16073.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Much is known about bovine lactoperoxidase but no data are available on its primary structure. In this work its main active fraction was isolated from cow's milk and sequenced using a conventional strategy. A clear similarity was found with human myeloperoxidase, eosinophil peroxidase and thyroperoxidase, the sequences of which were recently elucidated from those of their cDNAs and/or genes. The single peptide chain of bovine lactoperoxidase contains 612 amino acid residues, including 15 half-cystines and 4 or 5 potential N-glycosylation sites. The corresponding peptide segments of human myeloperoxidase, eosinophil peroxidase and thyroperoxidase display 55%, 54% and 45% identity with bovine lactoperoxidase, respectively, with 14 out of the 15 half-cystines present in each of the four enzymes being located in identical positions. The occurrence of an odd number of half-cystines in bovine lactoperoxidase supports the recent finding of a heme thiol released from this enzyme by a reducing agent, suggesting that the heme is bound to the peptide chain via a disulfide linkage, since the absence of free thiol in the enzyme was reported long ago.
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Affiliation(s)
- M M Cals
- Protein Unit, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
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12
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Yoshida S, Ye-Xiuyun. Isolation of Lactoperoxidase and Lactoferrins from Bovine Milk Acid Whey by Carboxymethyl Cation Exchange Chromatography. J Dairy Sci 1991. [DOI: 10.3168/jds.s0022-0302(91)78301-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Kinetic and molecular orbital studies on the rate of oxidation of monosubstituted phenols and anilines by lactoperoxidase compound II in comparison with the case of horseradish peroxidase. J Biol Phys 1991. [DOI: 10.1007/bf00417806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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14
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Dull TJ, Uyeda C, Strosberg AD, Nedwin G, Seilhamer JJ. Molecular cloning of cDNAs encoding bovine and human lactoperoxidase. DNA Cell Biol 1990; 9:499-509. [PMID: 2222811 DOI: 10.1089/dna.1990.9.499] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Peptide sequences obtained from cyanogen bromide fragments of bovine lactoperoxidase (bLPO) were used to design oligonucleotide probes for library screening. These probes were used to screen a cDNA library constructed from bovine mammary tissue. Three overlapping clones were obtained, the longest of which (T3) contained a reading frame of 712 amino acid residues. The encoded amino acid sequence was homologous to those recently reported for myelo-, thyro-, and eosinophil peroxidases. Two possible amino termini of the mature enzyme were identified, and the predicted mature protein matched previous molecular weight estimates of 78,500. Of eight bovine tissues tested, transcription of T3 sequences were detected in mammary tissue only. Using the bLPO cDNA as a probe, a single hybridizing clone was found in a human mammary gland cDNA library. This clone (M1) encoded the carboxy-terminal 324 residues of a peroxidase distinct from the other three known human peroxidases, and was closely related to bLPO. This result confirms the presence of at least one distinct lactoperoxidase in humans.
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Affiliation(s)
- T J Dull
- Ideon Corporation, Redwood City, CA 94063
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15
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Abstract
Bacteria produce a large number of different halogenated secondary metabolites. Haloperoxidases are believed to be the enzymes responsible for the halogenation reaction. Two classes of haloperoxidases, heme and nonheme, were isolated from different bacteria and their role in the biosynthesis of halogenated secondary metabolites was investigated. Two genes of bacterial haloperoxidases were cloned and can now be used to produce large quantities of the enzymes.
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Affiliation(s)
- K H Van Pée
- Institut für Mikrobiologie, Universität Hohenheim, Stuttgart, FRG
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16
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Resonance Raman characterization of heme Fe(IV)=O groups of intermediates of yeast cytochrome C peroxidase and lactoperoxidase. J Mol Struct 1989. [DOI: 10.1016/0022-2860(89)80004-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Modi S, Behere DV, Mitra S. Binding of aromatic donor molecules to lactoperoxidase: proton NMR and optical difference spectroscopic studies. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 996:214-25. [PMID: 2546604 DOI: 10.1016/0167-4838(89)90250-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The interaction of aromatic donor molecules with lactoperoxidase (LPO) was studied using 1H-NMR and optical difference spectroscopy techniques. pH dependence of substrate proton resonance line-widths indicated that the binding was facilitated by protonation of an amino acid residue (with pKa of 6.1) which is presumably a distal histidine. Dissociation constants evaluated from both optical difference spectroscopy and 1H-NMR relaxation measurements were found to be an order of magnitude larger than those for binding to horse radish peroxidase (HRP), indicating relatively weak binding of the donors to LPO. The dissociation constants evaluated in presence of excess of I- and SCN- showed a considerable increase in their values, indicating that the iodide and thiocyanate ions compete for binding at the same site. The dissociation constant of the substrate binding was, however, not affected by cyanide binding to the ferric centre of LPO. All these results indicate that the organic substrates bind to LPO away from the ferric center. Comparison of the dissociation constants between the different substrates suggested that hydrogen bonding of the donors with the distal histidine amino acid, and hydrophobic interaction between the donors and the active site contribute significantly towards the associating forces. Free energy, entropy and enthalpy changes associated with the LPO-substrate equilibrium have been evaluated. These thermodynamic parameters were found to be all negative and relatively low compared to those for binding to HRP. The distances of the substrate protons from the ferric center were found to be in the range 9.4-11.1 A which are 2-3 A larger than those reported for the HRP-substrate complexes. These structural informations suggest that the heme in LPO may be more deeply buried in the heme crevice than that in the HRP.
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Affiliation(s)
- S Modi
- Chemical Physics Group, Tata Institute of Fundamental Research, Colaba, Bombay, India
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18
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Horie S, Takizawa N. Molecular characteristics of many hemoproteins: a survey of molecular weights, sedimentation coefficients, other molecular parameters and amino acid compositions. J Theor Biol 1987; 129:117-37. [PMID: 3455456 DOI: 10.1016/s0022-5193(87)80206-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Data on molecular weights, sedimentation coefficients, other molecular parameters and amino acids compositions of many hemoproteins were collected from the literature and studied. The results of the survey gave a general view of the molecular characteristics of hemoproteins and also revealed the presence of various statistical correlations among the molecular parameters and amino acid compositions. Some of the correlations were found to be practically useful for the estimation of number of heme per molecule, molecular weight or partial specific volume. Discussions were made on the possible structural basis of the molecular characteristics of hemoproteins.
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Affiliation(s)
- S Horie
- Department of Biochemistry, School of Medicine, Kitasato University, Kanagawa, Japan
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19
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Sakurada J, Takahashi S, Shimizu T, Hatano M, Nakamura S, Hosoya T. Proton and iodine-127 nuclear magnetic resonance studies on the binding of iodide by lactoperoxidase. Biochemistry 1987; 26:6478-83. [PMID: 2827729 DOI: 10.1021/bi00394a028] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Interaction of an iodide ion with lactoperoxidase was studied by the use of 1H NMR, 127I NMR, and optical difference spectrum techniques. 1H NMR spectra demonstrated that a major broad hyperfine-shifted signal at about 60 ppm, which is ascribed to the heme peripheral methyl protons, was shifted toward high field by adding KI, indicating the binding of iodide to the active site of the enzyme; the dissociation constant was estimated to be 38 mM at pH 6.1. The binding was further detected by 127I NMR, showing no competition with cyanide. Both 1H NMR and 127I NMR revealed that the binding of iodide to the enzyme is facilitated by the protonation of an ionizable group with a pKa value of 6.0-6.8, which is presumably the distal histidyl residue. Optical difference spectra showed that the binding of an aromatic donor molecule to the enzyme is slightly but distinctly affected by adding KI. On the basis of these results, it was suggested that an iodide ion binds to lactoperoxidase outside the heme crevice but at the position close enough to interact with the distal histidyl residue which possibly mediates electron transport in the iodide oxidation reaction.
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Affiliation(s)
- J Sakurada
- Faculty of Pharmaceutical Sciences, Chiba University, Japan
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20
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Separation of two populations of endocytic vesicles involved in receptor-ligand sorting in rat hepatocytes. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(17)38412-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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21
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855 — Electrochemical conversion of lactoperoxidase, ceruloplasmin and alkaline phosphatase on mercury electrodes. ACTA ACUST UNITED AC 1986. [DOI: 10.1016/0302-4598(86)85028-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
The properties of a peroxidase in human colostrum were studied using antiserum against human myeloperoxidase. The peroxidase in human colostrum gave a single precipitin line against the antiserum on double immunodiffusion, and this precipitin line fused completely with the precipitin line formed between myeloperoxidase and the antiserum. The peroxidase activity in human colostrum was precipitated completely with anti-myeloperoxidase IgG, like myeloperoxidase activity. The peroxidase of colostral whey was purified to homogeneity. The purified enzyme consisted of two subunits of Mr 59,000 and 15,000, corresponding in size to the two subunits of myeloperoxidase. Immunostaining of a protein blot from a sodium dodecyl sulfate-polyacrylamide electrophoresis gel also showed that the peroxidase in the whey extract consisted of the same two subunits as myeloperoxidase. These results indicate that the peroxidase of human colostrum is identical with myeloperoxidase.
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Goff HM, Gonzalez-Vergara E, Ales DC. High resolution proton nuclear magnetic resonance spectroscopy of lactoperoxidase. Biochem Biophys Res Commun 1985; 133:794-9. [PMID: 3002359 DOI: 10.1016/0006-291x(85)90974-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The first high resolution proton nuclear magnetic resonance spectra are reported for the native ferric and ferric cyano complexes of bovine lactoperoxidase. The spectrum of the native species exhibits broad heme signals in a far downfield region characteristic of the high-spin ferric state. The low-spin cyano complex yields a proton nuclear magnetic resonance spectrum with signals as far as 68.5 ppm downfield and as far as -28 ppm upfield of the tetramethylsilane reference. These peak positions are anomalous with respect to those seen only as far as 35 ppm downfield in other cyano hemoprotein complexes. An extreme asymmetry in the unpaired spin delocalization pattern of the iron porphyrin is suggested. The unusual proton nuclear magnetic resonance properties parallel distinctive optical spectral properties and the exceptional resistance to heme displacement from the enzyme. Lactoperoxidase utilized in these studies was isolated from raw milk and purified by an improved, rapid chromatographic procedure.
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24
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Hildenbrandt GR, Aronson NN. Endocytosis of bovine lactoperoxidase by two carbohydrate-specific receptors in rat liver. Arch Biochem Biophys 1985; 237:1-10. [PMID: 2578766 DOI: 10.1016/0003-9861(85)90247-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A perfused rat liver took up bovine lactoperoxidase (LPO) by a Ca2+-dependent, saturable process. This endocytosis was accomplished by both hepatocytes and Kupffer or other nonparenchymal cells (NPCs). The mediating receptors were the Gal/GalNAc lectin of hepatocytes and the Man/GlcNAc lectin of NPCs. Blocking either one of these receptors caused a large shift in distribution of accumulated LPO into the cell type whose receptor was left unblocked, but the extent of uptake was unaffected and the rate was only moderately reduced. Effective inhibition of overall uptake into the perfused organ required the presence of competitors for both receptors. Conversely, LPO was an effective competitor of other ligands (asialoorosomucoid or mannan) for either of the two receptors. The major clearance capacity for LPO was associated with hepatocytes which in suspension took it up by a process completely inhibitable by asialofetuin (ASF) and at a rate more than three times greater than for ASF. A faster cycling time for Gal/GalNAc receptors when bound to LPO is suggested. The glycoprotein selectively lost its affinity for Man/GlcNAc receptors when digested by endoglycosidase H (endo H), suggesting that LPO contains mannose-rich oligosaccharides.
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25
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Magnusson RP, Taurog A, Dorris ML. Mechanisms of thyroid peroxidase- and lactoperoxidase-catalyzed reactions involving iodide. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(18)89814-3] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Dumontet C, Rousset B. Identification, purification, and characterization of a non-heme lactoperoxidase in bovine milk. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(17)43839-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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29
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Magnusson RP, Taurog A. Iodide-dependent catalatic activity of thyroid peroxidase and lactoperoxidase. Biochem Biophys Res Commun 1983; 112:475-81. [PMID: 6847661 DOI: 10.1016/0006-291x(83)91489-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Thyroid peroxidase (TPO) and lactoperoxidase (LPO) display significant catalatic activity at pH 7.0 in the presence of low concentrations of iodide, based both on measurements of H2O2 disappearance and O2 evolution. In the absence of iodide only minor catalatic activity was detected. The stimulatory effect of iodide could not be explained by protection of the enzymes against inactivation by H2O2. A mechanism is suggested involving an enzyme-hypoiodite complex as an intermediate.
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Sievers G, Gadsby PM, Peterson J, Thomson AJ. Assignment of the axial ligands of the haem in milk lactoperoxidase using magnetic circular dichroism spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 742:659-68. [PMID: 6301559 DOI: 10.1016/0167-4838(83)90285-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The absorption and MCD spectra of ferric lactoperoxidase from milk and its cyanide and fluoride derivatives have been measured in the near infrared and visible wavelength regions both at room temperature and at 4.2 K. By comparison with the MCD spectra of haemoproteins of known axial ligation, which also contain protohaem IX, it has been possible to arrive at suggestions for the axial ligation in lactoperoxidase. At room temperature oxidized lactoperoxidase has the haem iron in the high-spin state, and the results indicate that the proximal ligand of the haem iron is a histidine imidazole and that the sixth ligand is probably a carboxylate ion. At 4.2 K oxidized lactoperoxidase converts almost totally to a low-spin form, changing the sixth ligand to a histidine imidazole, which is in the imidazolate form.
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31
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Nishihara T, Gerton GL, Hedrick JL. Radioiodination studies of the envelopes from Xenopus laevis eggs. J Cell Biochem 1983; 22:235-44. [PMID: 6671992 DOI: 10.1002/jcb.240220405] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
To investigate the molecular basis of the observed morphological and biological characteristics of coelomic egg envelopes (CE), vitelline envelopes (VE), and fertilization envelopes (FE) of Xenopus laevis eggs, envelopes were radioiodinated under a variety of conditions: in situ, isolated and intact, or solubilized. The distribution of 125I in envelope components was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Each envelope type displayed unique profiles when iodinated in the intact state. A major constituent of VE, the 41,500 molecular weight component, was not labeled in the intact state, although the corresponding component of CE was heavily labeled. After dissociation of the envelope by guanidine-HCl or sodium dodecyl sulfate, all of the components could be radioiodinated. However, when the envelopes (VE and FE) were dissolved by heating and subsequently radioiodinated by lactoperoxidase, the resulting radioactivity profile was similar to that of the intact envelopes, suggesting that in the heat-dissolved envelope, the individual components retain similar structural relations as in the intact envelope. Quantitative but not qualitative differences were found between the inner and outer aspects of VE and FE. The significance of these findings is discussed in relation to what is known about the morphological, biological, and molecular properties of the envelopes.
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32
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Moldoveanu Z, Tenovuo J, Mestecky J, Pruitt KM. Human milk peroxidase is derived from milk leukocytes. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 718:103-8. [PMID: 6291620 DOI: 10.1016/0304-4165(82)90014-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Peroxidase enzymes present in human colostrum, saliva, polymorphonuclear leukocytes, and bovine milk were compared with respect to their molecular exclusion chromatographic behavior and immunological cross-reactivity. Human milk peroxidase gave an elution profile similar to myeloperoxidase derived from blood polymorphonuclear leukocytes. Human salivary peroxidase reacted with an antibody directed against bovine lactoperoxidase, but with the same antibody preparation no reaction was detected either with human milk peroxidase or leukocyte myeloperoxidase. We conclude that the peroxidase enzyme in human milk is different from the human salivary and the bovine enzymes and is probably derived from milk leukocytes.
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Judd RC. Surface peptide mapping of protein I and protein III of four strains of Neisseria gonorrhoeae. Infect Immun 1982; 37:632-41. [PMID: 6811436 PMCID: PMC347579 DOI: 10.1128/iai.37.2.632-641.1982] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Whole cells and isolated outer membranes (OMs) of four strains of gonococci were surface radioiodinated with either lactoperoxidase or Iodogen (Pierce Chemical Co., Rockford, Ill.). These preparations were solubilized in sodium dodecyl sulfate and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Surface-radioiodinated protein I (PI) and PIII bands were excised from the sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels and digested with alpha-chymotrypsin, and the resultant 125I-peptide fragments were resolved by high-voltage electrophoresis and thin-layer chromatography (i.e., surface peptide mapping). Radioemitting peptidic fragments were visualized by autoradiography. Results demonstrated that the PI molecule of each gonococcal strain studied had unique iodinatable peptides exposed on the surface of whole cells and OMs, whereas PIIIs appeared to have the same portion of the molecule exposed on the surface of bacteria or OMs, regardless of the gonococcal strain from which they were isolated. Many more radiolabeled peptides were seen in surface peptide maps of PIs from radiolabeled OMs than in those from radioiodinated whole cells, whereas different peptidic fragments were seen in the surface peptide maps of PIIIs from radiolabeled OMs than were seen in those from radiolabeled whole cells. These data suggest that PI may contribute strain-specific antigenic determinants and PIII may contribute cross-reactive determinants and that the surface exposure of PI and PIII is different in isolated OMs than in the OM of intact gonococci.
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Abstract
A peroxidase, purified from rat small intestine to apparent homogeneity as judged by polyacrylamide-gel electrophoresis, exhibited an absorbance ratio (A412/A280) of 0.783. Its Mr (44000 +/- 1000) and spectral properties were similar to those of the pig intestinal enzyme. The velocity constant for the reaction between rat intestinal peroxidase and hydrogen peroxide was found to be 1.8 x 10(7) M-1 . s-1. Benzhydroxamic acid inhibited the peroxidative oxidation of guaiacol by intestinal peroxidase from both species but the concentration required to cause half-inhibition of the enzyme from the rat was higher by one order of magnitude than for the pig enzyme. The amino acid composition of highly-purified pig intestinal peroxidase showed a relative abundance of basic amino acids (lysine and arginine) and was similar to that of lactoperoxidase, but not that of myeloperoxidase. The initial ten amino acid residues of this enzyme (the first reported partial sequence for a mammalian peroxidase) were also determined.
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Olsen RL, Flatmark T, Little C. Spectral properties of the oestrogen-induced rat uterus peroxidase II and some of its derivatives. Biochem J 1982; 201:91-4. [PMID: 6282264 PMCID: PMC1163612 DOI: 10.1042/bj2010091] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
1. The visible absorption spectrum of peroxidase II, isolated from the uterine tissue of oestradiol-treated rats, and some of its derivatives were recorded. The spectral properties of this enzyme are very similar to eosinophile peroxidase and lactoperoxidase, suggesting that these enzymes may have a similar form of haem as prosthetic group. 2. The uterine peroxidase is modified upon interaction with H2O2 and the difference spectrum of this modified enzyme is similar to that of complex II of lactoperoxidase. The modified enzyme was found to revert spontaneously to the native enzyme at rates which depended on the concentration of free enzyme and H2O2.
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Church WR, Rawitch AB, Ebner KE. The fluorescein-mediated interaction of bovine serum albumin with fluorescent derivatives of prolactin and other polypeptides in polarization of fluorescence based assays. Arch Biochem Biophys 1981; 206:285-90. [PMID: 6784680 DOI: 10.1016/0003-9861(81)90093-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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38
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Urch UA, Hedrick JL. Isolation and characterization of the hatching enzyme from the amphibian, Xenopus laevis. Arch Biochem Biophys 1981; 206:424-31. [PMID: 6784682 DOI: 10.1016/0003-9861(81)90110-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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39
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Urch UA, Hedrick JL. The hatching enzyme from Xenopus laevis: limited proteolysis of the fertilization envelope. JOURNAL OF SUPRAMOLECULAR STRUCTURE AND CELLULAR BIOCHEMISTRY 1981; 15:111-7. [PMID: 6965088 DOI: 10.1002/jsscb.1981.380150202] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Hatching in the amphibian Xenopus laevis involves release of an embryo-secreted hatching enzyme, a protease, which weakens the envelope surrounding the embryo. The envelope is not totally solubilized, which infers that only selected envelope components are hydrolyzed by the enzyme. The susceptibility of the glycoprotein components composing the envelope to hydrolysis by the hatching enzyme was investigated. Isolated envelopes in various physical states, ie, particulate and solubilized, were treated with the hatching enzyme, and the resulting envelope hydrolysis products were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The susceptibility of the envelope components to proteolysis was not a function of the state of the envelope. The envelope components most susceptible to proteolysis were the 125K and 118K components followed by the 60K and 71-77K components. These components are minor constituents of the envelope. The major constituents, 33K and 40K, were relatively resistant to hydrolysis by the hatching enzyme. From these observations, we infer that the envelope components hydrolyzed are components that link or bind together the major structural elements of the envelope, eg, the 33K and 40K components. Selective destruction of the components required for maintaining the structural integrity of the envelope, eg, the "nuts and bolts" of the structure, permits a weakening of the envelope that allows the embryo to hatch without having to destroy totally (hydrolyze) the envelope.
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Affiliation(s)
- U A Urch
- Department of Biochemistry and Biophysics, University of California, Davis 95616
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Etemadi AH. Membrane asymmetry. A survey and critical appraisal of the methodology. I. Methods for assessing the asymmetric orientation and distribution of proteins. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 604:347-422. [PMID: 7008847 DOI: 10.1016/0005-2736(80)90578-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This and the companion article are aimed at surveying the methods used for the study of membrane asymmetry. The techniques employed for the assessment of the asymmetric distribution and orientation of membrane proteins are reviewed in this article, whereas those pertaining to the unequal distribution of lipids are detailed in the companion paper. The use of immunological techniques and lectins, functions of proteins and their perturbations, chemical reagents, enzymatic isotopic labeling and enzymatic cleavage of membrane proteins and physical techniques are discussed and illustrated using recent examples of their application. Whenever appropriate, problems involving crypticity and non-availability or non-reactivity of functional sites, relevant chemical functions or protein fragments to appropriate ligands, reagents or modifying enzymes are envisaged and possible modification of the exposure of proteins during preparation of ghosts and other drawbacks are discussed, the use of different techniques and control experiments in conjunction is recommended for a more realistic assessment of the distribution and orientation of proteins.
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Chandler DK, Silvia JC, Ebner KE. Inactivation of galactosyltransferase by lactoperoxidase and N-acetylimidazole. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 616:179-87. [PMID: 6783077 DOI: 10.1016/0005-2744(80)90136-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Galactosyltransferase (UDPgalactose:D-glucose 4-beta-D-galactosyltransferase, EC 2.4.1.22) was totally inactivated by iodination with lactoperoxidase (donor:hydrogen-peroxide oxidoreductase, EC 1.11.1.7). Substrates protected against inactivation. The presence of 10 mM Mn2+ and 1 mM UDPgalactose gave partial protection which was enhanced by the addition of 10 mM N-acetylglucosamine, but not by glucose. These results are consistent with a conformational change upon binding of UDPgalactose. Only monoiodotyrosine and diiodotyrosine were identified in the pronase digest of iodinated galactosyltransferase. Galactosyltransferase was also inactivated with N-acetylimidazole and partial activity was restored by treating acetylated galactosyltransferase with hydroxylamine. These results suggest that tyrosine(s) is essential for galactosyltransferase activity.
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Sievers G. Structure of milk lactoperoxidase. A study using circular dichroism and difference absorption spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 624:249-59. [PMID: 7407237 DOI: 10.1016/0005-2795(80)90244-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Circular dichroism spectra of milk lactoperoxidase, its fluoride and cyanide derivatives, and those of ferrous lactoperoxidase and its carbonyl and cyanide compounds, were recorded in the wavelength region 200-670 nm. All derivatives have split ellipticity bands, suggesting that lactoperoxidase has a narrow heme pocket that prevents ligands forming linear iron-ligand bonds. Difference absorption spectroscopy of the enzyme in the far-ultraviolet region supports the previously held view that the fifth ligand of the heme iron is histidine. The secondary structure of lactoperoxidase, calculated from the far-ultraviolet circular dichroism spectrum, contains 65% beta-structure, 23% alpha-helix and 12% unordered structure. Reduction of lactoperoxidase with dithionite gives two forms, indicating that after reduction some compound arising from dithionite binds in the vicinity of the heme iron.
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Mena EE, Hoeser CA, Moore BW. An improved method of preparing rat brain synaptic membranes. Elimination of a contaminating membrane containing 2',3'-cyclic nucleotide 3'-phosphohydrolase activity. Brain Res 1980; 188:207-31. [PMID: 6245753 DOI: 10.1016/0006-8993(80)90569-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Synaptosomes were prepared from rat cortex by subjecting a washed crude mitochondrial pellet to centrifugation first on discontinuous Ficoll-isotonic sucrose gradients and then on discontinuous sucrose gradients. The synaptosome fraction, collected from the 7.5-14% Ficoll band (II), was further separated into two additional fractions, designated IIA and IIB, which bank at the 0.32-1.05 M and at the 1.05-1.6 M sucrose interfaces, respectively. Electron microscopic analysis showed that fraction IIB contained synaptosomes and extra terminal mitochondria and was essentially free of membrane fragments. Further characterization showed that IIB contained 69% of the protein and 83% of the lactic dehydrogenase activity of fraction II and had a specific activity of a 2',3'-cyclic nucleotide 3'-phosphohydrolase approximately 1% of that obtained with myelin. Fraction IIA had approximately 50% the specific activity of the 2',3'-cyclic nucleotide 3'-phosphohydrolase found in myelin. Synaptic plasma membranes were prepared by lysing fraction IIB in 1 mM sodium phosphate, 0.1 mM EDTA at pH 8.5 and subjecting this preparation to centrifugation on a discontinuous sucrose density gradient. Enzymatic analysis indicated that membranes banding at the 0.6-0.8 M sucrose interface had high specific activities of plasma membrane enzymes (e.g. acetylcholinesterase, ATPase, 5'-nucleotidase). The specific activity of the (Na+ + K+)-ATPase in the purified membrane preparation was 8-fold higher than that in the original homogenate. Specific activities of various marker enzymes indicated that the composition of these membrane preparations for the most part was synaptic plasma membranes, approximately 7% mitochondrial outer membranes and 3% a membrane containing 2',3'-cyclic nucleotide 3'-phosphohydrolase activity. The polypeptide compositions of three possible contaminating membranes and of synaptic membranes were compared by electrophoresis in 6-20% gradient polyacrylamide gels in the presence of sodium dodecyl sulfate. Whereas mitochondrial and myelin membranes had distinct compositions, the compositions of the microsomal and synaptosomal plasma membranes were similar. Synaptic plasma membranes contained at least 27 polypeptides; the three major polypeptides had molecular weights of 103,000; 54,000; and 50,000. The major polypeptides of soluble synaptosomal proteins had molecular weights of 54,000 and 42,000.
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Urch UA, Nishihara T, Hedrick JL. The use of radioiodinated protein substrates for the assay of trypsin and the hatching enzyme from the amphibian Xenopus laevis. Anal Biochem 1979; 100:352-6. [PMID: 525784 DOI: 10.1016/0003-2697(79)90240-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Andersen T, Ebner K. Reaction of the histidines of prolactin with ethoxyformic anhydride. A binding site modification. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(19)86621-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Bag J, Sells BH. Heterogeneity of the nonpolysomal cytoplasmic (free) mRNA . protein complexes of embryonic chicken muscle. EUROPEAN JOURNAL OF BIOCHEMISTRY 1979; 99:507-16. [PMID: 499213 DOI: 10.1111/j.1432-1033.1979.tb13282.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Rawitch AB, Taurog A, Chernoff SB, Dorris ML. Hog thyroid peroxidase: physical, chemical, and catalytic properties of the highly purified enzyme. Arch Biochem Biophys 1979; 194:244-57. [PMID: 443801 DOI: 10.1016/0003-9861(79)90615-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Tas PW, Sells BH. Accessibility of ribosomal proteins to lactoperoxidase-catalyzed iodination following phosphorylation and during subunit interaction. EUROPEAN JOURNAL OF BIOCHEMISTRY 1978; 92:271-8. [PMID: 729591 DOI: 10.1111/j.1432-1033.1978.tb12745.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Lactoperoxidase-catalyzed iodination was employed as a probe to monitor conformational change in 40-S ribosomal subunits from rat liver. Using this probe, it was observed that phosphorylation of protein S6 resulted in no detectable change in the iodination pattern of 40-S subunit proteins. These results suggest that the conformation of the small subunit remains unaltered following phosphorylation. On the other hand, the differences noted in the iodination pattern between 40-S ribosomal proteins derived from isolated subunits and those from 80-S monosomes, suggest that the 40-S subunit undergoes a conformational change during association with the 60-S subunit. Following 40-S and 60-S subunit association, proteins S2, S3, S5, S6, S8, S10 and S14 became less accessible to iodination. It is suggested that these proteins may be located at the interface between the 40-S and 60-S subunits.
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