Purification and some properties of the extracellular acid proteases from Mucor renninus

A complex of proteases was fractionated into three enzymes by chromatography of a crude enzyme preparation obtained from culture fluid of the fungus Mucor renninus on biospecific polystyrene adsorbent. Electrophoretically homogeneous proteases I-III were obtained by subsequent rechromatography on biospecific adsorbent and gel filtration on Sephadex G-75. Optimal proteolytic activities occurred at pH 4.25; 3.5 and 2.5 for enzymes I, II and III, respectively. Milk-clotting activity was exhibited only by protease II. All three proteases hydrolysed haemoglobin, Na caseinate and bovine serum albumin. Enzyme I hydrolysed Na caseinate the most effectively, while haemoglobin was the most effective substrate for proteases II and III. Trypsinogen was activated only by protease I. All three enzymes have a molecular weight ～35 000 as determined by gel chromatography on Sephadex G-75 column and by sodium dodecylsulphate disc electrophoresis. Isoelectric points, pH-stability range, amino acid composition, carbohydrate content were determined for each enzyme and the influence of metal ions (Ca²⁺, Mg²⁺, Cu²⁺, Co²⁺) on proteolytic activities of these enzymes studied.     

On preparative separation of brain mitochondrial monoamine oxidases.

A method was developed for solubilization from bovine brain stem mitochondrial fraction of monoamine oxidases deminating biogenic amines. Preparative separation of the monoamine oxidases, possessing different substrate specificities, was achieved by column chromatography on a biospecific adsorbent AH-Sepharose 4 B. The enzyme preparations thus obtained did not contain any detectable by disc-electrophoresis of isoelectrofocusing in polyacrylamide gels proteins which were devoid of the monoamine oxidase activity.     

Purification and characterization of 1-nitropyrene nitroreductases from Bacteroides fragilis.

We isolated four nitroreductases from Bacteroides fragilis GAI0624 and examined their physicochemical and functional properties. Two major enzyme activities were found in the adsorbed and unadsorbed fractions from DEAE-cellulose column chromatography. The adsorbed fraction was subjected to Sephadex G-200 column chromatography, and two further activities were separated. One has high nitroreductase activity (nitroreductase I), and the other has low activity and relatively high molecular weight (nitroreductase III). The nitroreductase I fraction was subjected to hydroxylapatite and chromatofocusing column chromatography, and nitroreductase I was purified about 416-fold with a yield of 6.77%. The unadsorbed fraction from DEAE-cellulose column chromatography was subjected to Sepharose 2B and Sepharose 6B column chromatography. Two enzyme activities were obtained by the Sepharose 6B column chromatography. One has high activity (nitroreductase II), and the other has low activity (nitroreductase IV). Nitroreductase II was rechromatographed by Sepharose 6B gel filtration and purified about 178-fold with a yield of 9.65%. The four enzymes (nitroreductases I, II, III, and IV) were shown to be different by several criteria. Their molecular weights, determined by gel filtration, were 52,000, 320,000, 180,000, and 680,000, respectively. The substrate specificity, the effect on mutagenicity of mutagenic nitro compounds, of nitroreductases I, III, and IV was relatively high for 1-nitropyrene, dinitropyrenes, and 4-nitroquinoline 1-oxide, respectively, but nitroreductase II had broad specificity. Nitroreductase activity required a coenzyme; nitroreductases II, III, and IV were NADPH linked, but nitroreductase I was NADH linked. All enzyme activity was enhanced by addition of flavin mononucleotide and inhibited significantly by dicumarol, p-chloromercuribenzoic acid, o-iodosobenzoic acid, sodium azide, and Cu2+.(ABSTRACT TRUNCATED AT 250 WORDS)     

Purification and characterization of 1-nitropyrene nitroreductases from Bacteroides fragilis

We isolated four nitroreductases from Bacteroides fragilis GAI0624 and examined their physicochemical and functional properties. Two major enzyme activities were found in the adsorbed and unadsorbed fractions from DEAE-cellulose column chromatography. The adsorbed fraction was subjected to Sephadex G-200 column chromatography, and two further activities were separated. One has high nitroreductase activity (nitroreductase I), and the other has low activity and relatively high molecular weight (nitroreductase III). The nitroreductase I fraction was subjected to hydroxylapatite and chromatofocusing column chromatography, and nitroreductase I was purified about 416-fold with a yield of 6.77%. The unadsorbed fraction from DEAE-cellulose column chromatography was subjected to Sepharose 2B and Sepharose 6B column chromatography. Two enzyme activities were obtained by the Sepharose 6B column chromatography. One has high activity (nitroreductase II), and the other has low activity (nitroreductase IV). Nitroreductase II was rechromatographed by Sepharose 6B gel filtration and purified about 178-fold with a yield of 9.65%. The four enzymes (nitroreductases I, II, III, and IV) were shown to be different by several criteria. Their molecular weights, determined by gel filtration, were 52,000, 320,000, 180,000, and 680,000, respectively. The substrate specificity, the effect on mutagenicity of mutagenic nitro compounds, of nitroreductases I, III, and IV was relatively high for 1-nitropyrene, dinitropyrenes, and 4-nitroquinoline 1-oxide, respectively, but nitroreductase II had broad specificity. Nitroreductase activity required a coenzyme; nitroreductases II, III, and IV were NADPH linked, but nitroreductase I was NADH linked. All enzyme activity was enhanced by addition of flavin mononucleotide and inhibited significantly by dicumarol, p-chloromercuribenzoic acid, o-iodosobenzoic acid, sodium azide, and Cu2+.(ABSTRACT TRUNCATED AT 250 WORDS)     

On Preparative Separation of Brain Mitochondrial Monoamine Oxidases

A method was developed for solubilization from- bovine brain stem mitochondrial fraction of monoamine oxidases deminating biogenic amines. Preparative separation of the monoamine oxidases, possessing different substrate specificities, was achieved by column chromatography on a biospecific adsorbent AH-Sepharose 4 B. The enzyme preparations thus obtained did not contain any detectable by disc-electrophoresis or isoelectrofocusing in polyacrylamide gels proteins which were devoid of the monoamine oxidase activity.     

Ca2+-dependent cysteine proteinase, calpains I and II are not phosphorylated in vivo

To clarify phosphorylation of calpains I and II in vivo, we purified both calpains concurrently from the [32P] metabolic-labeled human chronic myelogenous leukemia cell line K-562. By Ultragel AcA34 column chromatography, enzymatic activity of calpain I was separated from [32P] radioactivity. Whereas calpain II activity was closely associated with [32P] radioactivity on Ultragel AcA34 and Blue Sepharose CL-6B column chromatographies. By the above purification procedures, calpain I was purified 1300-fold from the crude extract and calpain II was 920-fold from the original sample, respectively. Autoradiographies of purified calpains I and II from [32P] labeled K-562 cells revealed that both calpains were not specifically phosphorylated in vivo. The autophosphorylation in vitro on calpains and modulation of their proteolytic activities reported recently thus may not occur within cells.     

Method of purification of glucose oxidase by means of affinity chromatography on immunoabsorbent]

The possibility to purify glucose oxidase from Penicillium vitale on immunosorbent containing specific antibodies to the enzyme covalently bound with Sepharose 4B is studied. The method of affinity chromatography was applied, beside routine methods of fractionating blood serum proteins, to isolate specific antibodies from antiserum of rabbits immunized with glucose oxidase. Immobilized on Sepharose glucose oxidase was used as biospecific sorbent. Specific antibodies to the enzyme were isolated using chromatograpy of gamma-globulins mixture followed by protein desorption from the column with 1 M NaC1 and 3% glucose. Antibodies were immobilized by their covalent binding to activated Sepharose. The immunosorbent obtained was used to purify low active preparation of glucose oxidase by means of affinity chromatography under conditions worked out for the antibodies isolation. The enzyme was eluted from the column with 1 M NaC1 (pH 3.0) containing 3% glucose. 5-Fold purified enzyme preparation was isolated.     

The calcium-dependent proteolytic system calpain-calpastatin in Drosophila melanogaster.

Ca2+-dependent proteolytic activity was detected at pH 7.5 in head extracts of the fruit fly Drosophila melanogaster. This activity was abolished by iodoacetate, but was unaffected by phenylmethanesulphonyl fluoride. These properties resemble those of the Ca2+-dependent thiol-proteinase calpain. The activity appeared at Mr 280,000 on Sepharose CL-6B gel chromatography. DEAE-cellulose chromatography revealed two activity peaks, with elution positions corresponding to vertebrate calpains I and II. The fly head enzymes were inhibited by a heat-stable and trypsin-sensitive component of the fly head extract, which also inhibited calpains from rat kidney. The inhibitor emerged from Sepharose CL-6B columns at Mr 310,000 and from DEAE-cellulose at a position corresponding to the protein inhibitor calpastatin from other sources. It is concluded that Drosophila heads comprise the Ca2+-dependent calpain-calpastatin proteolytic system.     

Poly AB for an Immobilized Trypsin

Pig polyclonal antibodies against the biospecific complex of trypsin with its inhibitor “antilysine” were prepared by affinity chromatography on trypsin-bound beaded cellulose. The antibodies were characterised by ion exchange FPLC and SDS PAGE as pure IgG. The catalytic activity of trypsin was not affected by interaction with these antibodies, even in the presence of excess of antibody. Trypsin, biospecifically bound to CNBr-activated Sepharose 4B, displayed full catalytic activity.     

Cleavage of human serum immunoglobulin G by an immobilized pepsin preparation

In order to obtain an efficacious and safe immunoglobulin G (IgG) preparation for intravenous use, the digestion of IgG with an immobilized pepsin (EC 3.4.23.1) preparation was studied. Thus, pepsin was immobilized onto glutaraldehyde-activated AH-Sepharose 4B under acidic conditions. THe enzymatic properties, such as proteolytic activity, pH-activity profile and heat stability, of the immobilized pepsin preparation were examined. The immobilized pepsin retained more than 40% of its proteolytic activity toward N-acetyl-L-phenylalanyl-L-3,5-diiodo-tyrosine and more than 30% toward IgG, and also remarkable stability as compared with free pepsin. The immobilized pepsin thus prepared was efficiently used for the limited cleavage of IgG and the gel-filtration effect of the column made it easily possible to yield the F(ab')2-rich fraction for intravenous use.     

Spectroimmunochemistry using colloidal gold bioconjugates

Using surface-enhanced infrared absorption (SEIRA) spectroscopy of dry films of colloidal gold (CG) bioconjugates with protein A, it is shown that certain characteristic bands of the protein (e.g., amide I, amide II and some other vibration modes) are essentially affected by the metal surface. Thus, the method may be used for controlling the quality of such bioconjugates. Moreover, it is demonstrated that the biospecific reaction of protein A attached to CG particles with human immunoglobulin G (IgG) results in further essential changes in SEIRA spectra, providing a means for an easy and rapid IR spectroscopic detection of biospecific immunochemical interactions (i.e., spectroimmunochemistry). The results obtained can form a basis for developing test systems for detecting various biospecific interactions.     

Purification and characterization of multiple species (isolectins) of a slime mold lectin implicated in intercellular adhesion.

An improved purification procedure for the carbohydrate-binding proteins (lectins) of cohesive Polysphondylium pallidum cells has been devised. The procedure uses extraction of cells with lactose-containing buffer followed by ammonium sulfate precipitation and affinity chromatography of the redissolved precipitate on a column of acid-treated Sepharose 6B. All hemagglutination activity is adsorbed to the column and recoveries are about 70% of the activity of the starting cell lysate. Sodium dodecyl sulfate-gel electrophoresis of the protein obtained with this procedure resolved three subunits with molecular weights of 26,500 (A), 26,000 (B), and 25,000 (C). Three species are resolved by isoelectric focusing with apparent pI values of 6.4 (I), 7.3 (II), and 7.5 (III) which contain Subunits A, B, and C in the following ratios: I, B:C at 2:1; II, A:B at 2:1, and III, A:B at 1:2. All three isoforms agglutinate rabbit and human type O erythrocytes and are thus isolectins. Isoforms II and III are separated from Isoform I by galactose-gradient elution of the Sepharose 6B column. Isoforms II and III aggregate extensively (nonamers and multiples thereof), but reduction with 2-mercaptoethanol reverses this process yielding a single species of Mr = 73,000 (trimer). Isoform I exists as trimers and hexamers and reduction has no effect on this distribution. Amino acid compositions and tryptic peptide maps of S-[14C]carboxymethyl-isolectins indicate that Subunits A and B are very similar and may represent the same peptide chain, while Subunit C is a peptide quite distinct from A and B.     

Isolation and characterization of two major serum proteins from the dogfish, Mustelus canis, C-reactive protein and amyloid P component

Two major serum components from the dogfish, Mustelus canis, have been isolated using affinity chromatography. Both proteins bind to an AH-Sepharose 4B-phosphorylcholine affinity matrix in the presence of Ca2+ and are eluted from the column by EDTA. Upon readdition of Ca2+ to the eluted proteins, the two proteins can be separated by passage through a column of Sepharose CL-4B. The first protein, C-reactive protein, passes through the Sepharose CL-4B column in the presence of Ca2+ whereas the second protein, serum amyloid P component, remains bound. The serum amyloid P component is then eluted from the Sepharose CL-4B in pure form by EDTA. The dogfish C-reactive protein isolated by the phosphorylcholine affinity matrix precipitates with pneumococcal C-polysaccharide and with a synthetic derivative of bovine serum albumin to which phosphorylcholine is covalently attached. The precipitation is inhibited by either EDTA or by phosphorylcholine. Dogfish C-reactive protein has a molecular weight of approximately 250,000 with dimeric subunits of Mr = 50,000. Upon addition of beta-mercaptoethanol these dimeric subunits dissociate to two identical monomeric subunits of Mr = 25,000. The protein cross-reacts immunologically with goat antisera prepared against rabbit C-reactive protein. The dogfish serum amyloid P component has a molecular weight of at least 250,000 with monomeric subunits of Mr = 25,000. Cross-reactivity of the amyloid P component with the C-reactive protein could not be shown. However, NH2-terminal sequence analysis of the first 20 amino acids showed some homology. The relationship of dogfish C-reactive protein to the C-reactive proteins in Limulus polyphemus and in rabbits and humans is discussed.     

Purification and some properties of Candida albicans DNA polymerases.

DNA polymerases of Candida albicans were purified to near homogeneity. Three well distinguished peaks of DNA polymerase activity (Enzyme I, II and III respectively) were obtained by DEAE-Sephacel chromatography. This purification step was followed by column chromatographies on Sepharose 6B and denatured DNA-cellulose. The enzymes' molecular mass and biochemical properties, including their inhibition by aphidicolin, were studied. Molecular mass was determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and was found to be 110 kDa for Enzyme I, 80 kDa for Enzyme II and 50 kDa for Enzyme III.     

Affinity chromatography with amniotic fluid somatomedin binding protein in the purification of insulin-like growth factor I

A simplified procedure has been developed for the isolation of insulin-like growth factor I from human plasma by use of affinity chromatography with the somatomedin binding protein. After acidification of human plasma and separation of insulin-like growth factor I and endogenous binding protein by cation exchange chromatography on SP-Sephadex the material was passed through a column packed with pure human amniotic fluid binding protein covalently coupled to Sepharose. The bound insulin-like growth factors I and II were eluted by 1M acetic acid and separated on a Mono S cation exchange column by use of a salt gradient. The 30 micrograms insulin-like growth factor I and 18 micrograms insulin-like growth factor II recovered from 1 liter plasma gave an overall recovery of 30% for insulin-like growth factor I but only 2.5% for insulin-like growth factor II.     

Multiple Forms of Rice Seeds β-Amylases on Zymogram

Hen lysozyme modified with histamine (HML) and Japanese quail lysozyme (JQL) were treated with immobilized metal ion affinity chromatography to analyze the states of their imidazole groups. When Ni(II) was used as the metal ion immobilized, JQL was strongly retained in a Ni(II)-chelating Sepharose column, while hen lysozyme and HML were hardly retained in the same column. All of these lysozymes have a histidine imidazole group at the 15th position, while JQL has an additional histidine imidazole group at the 103rd position and HML has an additional imidazole group covalently attached to Asp101. Thus, I concluded that the imidazole group at the 103rd position of JQL is exposed to the solvent and recognized by the metal ion, but that the imidazole group attached to Asp101 in HML is localized to a hydrophobic region and not recognized by the metal ion.     

Purification and Some Properties of Candida albicans DNA Polymerases

Abstract

DNA polymerases of Candida albicans were purified to near homogeneity. Three well distinguished peaks of DNA polymerase activity (Enzyme I, II and III respectively) were obtained bv DEAE-Sephacel chromatography. This purification step was followed by column chromatographies on Sepharose 6B and denatured DNA-cellulose. The enzymes molecular mass and biochemical properties, including their inhibition by aphidicolin, were studied. Molecular mass was determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and was found to be 110 kDa for Enzyme I, 80 kDa for Enzyme II and 50 kDa for Enzyme III.     

Expression of rice (Oryza sativa L. var. Nipponbare) alpha-galactosidase genes in Escherichia coli and characterization

Two putative alpha-galactosidase genes from rice (Oryza sativa L. var. Nipponbare) belonging to glycoside hydrolase family 27 were cloned and expressed in Escherichia coli. These enzymes showed alpha-galactosidase activity and were purified by Ni Sepharose column chromatography. Two purified recombinant alpha-galactosidases (alpha-galactosidase II and III; alpha-Gal II and III) showed a single protein band on SDS-PAGE with molecular mass of 42 kDa. These two enzymes cleaved not only alpha-D-galactosyl residues from the non-reducing end of substrates such as melibiose, raffinose, and stachyose, but also liberated the galactosyl residues attached to the O-6 position of the mannosyl residue at the reducing-ends of mannobiose and mannotriose. In addition, these enzymes clipped the galactosyl residues attached to the inner-mannosyl residues of mannopentaose. Thus, alpha-Gal II catalyzes efficient degalactosylation of galactomannans, such as guar gum and locust bean gum.     

Human serum immunoglobulin G3 subclass bound preferentially to asialo-, agalactoimmunoglobulin A1/Sepharose.

As we reported before, exoglycosidase treatment of human serum IgA1 changed it to a sticky molecule. In order to examine the presence of the specific binding protein to the sticky IgA1 in human serum, IgA1, asialo-IgA1 (IgA1-S) and asialo-, agalacto-IgA1 (IgA1-SG)/Sepharose column chromatography of normal human serum was carried out. Purified hinge glycopeptide (HGP33) prepared from IgA1 was used for the preparation of HGP/Sepharose. A portion of the serum protein was bound to those columns and eluted with the buffer containing 1.0 M NaCl. About four times the amount of protein was eluted from the IgA1-SG/Sepharose column than that from IgA1/Sepharose. Most of the eluted protein was IgG, and the IgG1 and IgG3 subclasses but neither IgG2 nor IgG4 was dominant. Under the lower salt concentration, a portion of IgG was also bound to the HGP-SG/Sepharose column. The obtained results coincide well with the previous report of the co-present of IgG1 and IgG3 with deposited IgA1 in IgA nephropathy patients (Aucouturier, P., et al. (1989) Clin. Immunol. Immunopathol. 51, 338-347). Thus, the results solved the question of why the IgG3 was co-present with deposited IgA1 in IgA nephropathy patients.     

Purification of heparinase and heparitinase by affinity chromatography on glycosaminoglycan-bound ah-sepha-rose 4b

Heparinase and heparitinase were separated from an extract of Flavobacterium heparinum, induced with heparin by using column chromatography on hydroxylapatite. As the heparinase preparation contained chondroitinases B and C, chondroitinase B was removed by rechromatography on a hydroxylapatite column. Chondroitinase C was then eliminated by column chromatography on O-phosphono(“phospho”)-cellulose. The heparinase preparation thus obtained was free from sulfoamidase for 2-deoxy-2-sulfoamino-D-glucose (GlcN-2S), sulfatase for 2-amino-2-deoxy-6-O-sulfo D-glucose (GlcN-6S), as well as (δ_4,5glycosiduronase for the unsaturated disaccharides obtained from heparin. The remaining sulfatase for 4-deoxy-α-L-thero-hex-4-enopyranosyluronic acid 2-sulfate (δUA-2S) in the heparinase preparation was removed by affinity chromatography with dermatan sulfate-bound AH-Sepharose 4B coated with dermatan sulfate. The heparitinase preparation separated by column chromatography on hydroxyla patite was purified by affinity chromatography with heparin-bound AH-Sepharose 4B coated with heparin. Sulfatase for 2-amino-2-deoxy-6-O-sulfo-D-glucose (GlcN-6S) and δ_4,5glycosiduronase for the unsaturated disaccharides obtained from heparin were removed by this chromatography. Sulfatase for 4-deoxy-α-L-threo-hex-4-enopyranosyluronic acid 2-sulfate (δUA-2S) remaining in the heparitinase preparation was finally removed by column chromatography on hydroxylapatite. The recoveries of the purified preparations of heparinase and heparitinase were estimated to be 39 and 50%, respectively, from the crude enzyme fractions obtained by the first column chromatography on hydroxyl- patite. The purified heparinase and heparitinase were free from all enzymes that could degrade the sulfated unsaturated disaccharides produced from heparin with heparinase.