Hyaluronidase and Chondroitinase.

Glycosaminoglycans (GAGs) are important constituents of the extracellular matrix that make significant contributions to biological processes and have been implicated in a wide variety of diseases. GAG-degrading enzymes with different activities have been found in various animals and microorganisms, and they play an irreplaceable role in the structure and function studies of GAGs. As two kind of important GAG-degrading enzymes, hyaluronidase (HAase) and chondroitinase (CSase) have been widely studied and increasing evidence has shown that, in most cases, their substrate specificities overlap and thus the "HAase" or "CSase" terms may be improper or even misnomers. Different from previous reviews, this article combines HAase and CSase together to discuss the traditional classification, substrate specificity, degradation pattern, new resources and naming of these enzymes.

Highly sulfated hexasaccharide sequences isolated from chondroitin sulfate of shark fin cartilage: insights into the sugar sequences with bioactivities.

Chondroitin sulfate (CS) chains regulate the development of the central nervous system in vertebrates and are linear polysaccharides consisting of variously sulfated repeating disaccharides, [-4GlcUAß1-3GalNAcß1-](n), where GlcUA and GalNAc represent D-glucuronic acid and N-acetyl-D-galactosamine, respectively. CS chains containing D-disaccharide units [GlcUA(2-O-sulfate)-GalNAc(6-O-sulfate)] are involved in the development of cerebellar Purkinje cells and neurite outgrowth-promoting activity through interaction with a neurotrophic factor, pleiotrophin, resulting in the regulation of signaling. In this study, to obtain further structural information on the CS chains containing d-disaccharide units involved in brain development, oligosaccharides containing D-units were isolated from a shark fin cartilage. Seven novel hexasaccharide sequences, ΔO-D-D, ΔA-D-D, ΔC-D-D, ΔE-A-D, ΔD-D-C, ΔE-D-D and ΔA-B-D, in addition to three previously reported sequences, ΔC-A-D, ΔC-D-C and ΔA-D-A, were isolated from a CS preparation of shark fin cartilage after exhaustive digestion with chondroitinase AC-I, which cannot act on the galactosaminidic linkages bound to D-units. The symbol Δ stands for a 4,5-unsaturated bond of uronic acids, whereas A, B, C, D, E and O represent [GlcUA-GalNAc(4-O-sulfate)], [GlcUA(2-O-sulfate)-GalNAc(4-O-sulfate)], [GlcUA-GalNAc(6-O-sulfate)], [GlcUA(2-O-sulfate)-GalNAc(6-O-sulfate)], [GlcUA-GalNAc(4-O-, 6-O-sulfate)] and [GlcUA-GalNAc], respectively. In binding studies using an anti-CS monoclonal antibody, MO-225, the epitopes of which are involved in cerebellar development in mammals, novel epitope structures, ΔA-D-A, ΔA-D-D and ΔA-B-D, were revealed. Hexasaccharides containing two consecutive D-units or a B-unit will be useful for the structural and functional analyses of CS chains particularly in the neuroglycobiological fields.

[Purification and immobilization of chondroitinase from Aeromonas sobria YH 311].

Chondroitinase has been used as an important tool in the study of the structure, function and distribution of glycosaminoglycans for many years. Recently, the enzyme has been reported to be a potential enzyme for chemonucleolysis, an established treatment for intervertebral disc protrasion. In this paper, a chondroitinase had been purified from the culture supernatant of Aeromonas sobria YH311 using a simple purification procedure of ammonium sulfate precipitation, QAE-Sephadex A50 ion exchange chromatography and Sephadex G-150 gel filtration. The immobilization of purified chondroitinase using sodium alginate or cellulose as carriers has also been studied. The chondroitinase obtained from Aeromonas sobria YH311 was purified 55-fold to 95.3% pure, the specific activity of the purified enzyme was 31.86u/mg and the yield was 37%. The molecular weight of chondroitinase from Aeromonas sobria YH311 was determined by SDS-PAGE to be 80kD, which was almost the same as those chondroitinase AC from Arthrobacter aurescens, Aeromonas liquefaciens and Flavobacterium heparinum. But its isoelectric point was 4.3 - 4.6, which was far lower than the microbial chondroitinase AC. After the immobilization on sodium alginate or cellulose, the properties of chondroitinase changed greatly. The optimum temperature and pH of the free enzyme were 50 degrees C and 7.0 respectively, and about 10% activity remained after heat treatment at 80 degrees C for 20 minutes, and 47% activity remained after two weeks storage at 4 degrees C. The chondroitinase immobilized on sodium alginate had the optimum temperature and pH of 40 degrees C and 7.0 respectively, about 50% activity remained after 80 degrees C heat treatment for 120 minutes and 50% remained after 30 days storage at 4 degrees C. The chondroitinase immobilized on cellulose had the optimum temperature and pH of 70 degrees C and 6.0 respectively, and more than 70% activity remained after heat treatment at 80 degrees C and 30 days storage at 4 degrees C. The yield of the immobilization was very low, with 18.56% for alginate and 18.86% for cellulose.

An improved methodology to produce Flavobacterium heparinum chondroitinases, important instruments for diagnosis of diseases.

Chondroitinases are very important tools for the identification and structural analysis of proteoglycans. Enzymic analysis with Flavobacterium heparinum chondroitinases has shown that chondroitin sulphate and dermatan sulphate structures are modified in many human diseases, suggesting a diagnostic value for these enzymes. Furthermore, it was recently shown that F. heparinum chondroitinases AC and B inhibit tumoural cell growth, invasion and angiogenesis. Due to the increasing importance of F. heparinum chondroitinases, we investigated optimized conditions for preparation and assay of chondroitinases AC, B and C. The Dimethylmethylene Blue assay was modified and fully developed to measure the chondroitinase activities of crude extracts of F. heparinum. This method estimates chondroitin sulphate or dermatan sulphate depolymerization upon the digestion of chondroitinase, and was compared with A (232), which measures the unsaturated products formed. Trypticase was the best culture medium, both for bacterial growth and enzyme induction. The chondroitinases were solubilized by ultrasound under conditions that do not completely disrupt the cells, suggesting that they are located at the periplasmic space. Maximum chondroitinase induction occurred in the presence of 0.2-1.0 g/l chondroitin sulphate. Chondroitin sulphate-degradation products were also inducers, but heparin and heparan sulphate were not. Chondroitinases AC, B and C were separated from each other by hydrophobic-interaction chromatography on Phenyl-Sepharose HP. When contaminant proteins were first removed from crude extract by Q-Sepharose, the chondroitinases could be purified to homogeneity in this phenyl-Sepharose chromatographic step.

Preparation and purification of Flavobacterium heparinum chondroitinases AC and B by hydrophobic interaction chromatography.

Flavobacterium heparinum is a soil bacterium that produces several mucopolysaccharidases such as heparinase, heparitinases I and II, and chondroitinases AC, B, C and ABC. The purpose of the present study was to optimize the preparation of F. heparinum chondroitinases, which are very useful tools for the identification and structural characterization of chondroitin and dermatan sulfates. We observed that during the routine procedure for cell disruption (ultrasound, 100 kHz, 5 min) some of the chondroitinase B activity was lost. Using milder conditions (2 min), most of the chondroitinase B and AC protein was solubilized and the enzyme activities were preserved. Tryptic soy broth without glucose was the best culture medium both for bacterial growth and enzyme induction. Chondroitinases AC and B were separated from each other and also from glucuronidases and sulfatases by hydrophobic interaction chromatography on HP Phenyl-Sepharose. A rapid method for screening of the column fractions was also developed based on the metachromatic shift of the color of dimethylmethylene blue.

Preparation and purification of Flavobacterium heparinum chondroitinases AC and B by hydrophobic interaction chromatography

Flavobacterium heparinum is a soil bacterium that produces several mucopolysaccharidases such as heparinase, heparitinases I and II, and chondroitinases AC, B, C and ABC. The purpose of the present study was to optimize the preparation of F. heparinum chondroitinases, which are very useful tools for the identification and structural characterization of chondroitin and dermatan sulfates. We observed that during the routine procedure for cell disruption (ultrasound, 100 kHz, 5 min) some of the chondroitinase B activity was lost. Using milder conditions (2 min), most of the chondroitinase B and AC protein was solubilized and the enzyme activities were preserved. Tryptic soy broth without glucose was the best culture medium both for bacterial growth and enzyme induction. Chondroitinases AC and B were separated from each other and also from glucuronidases and sulfatases by hydrophobic interaction chromatography on HP Phenyl-Sepharose. A rapid method for screening of the column fractions was also developed based on the metachromatic shift of the color of dimethylmethylene blue

Purification and properties of a novel glycosaminoglycan depolymerase from Streptococcus intermedius strain UNS 35.

A glycosaminoglycan (GAG) depolymerase that acts on chondroitin sulphate A (CS-A), chondroitin sulphate C (CS-C) and hyaluronic acid (HA) was purified to apparent homogeneity from a culture of Streptococcus intermedius, strain UNS 35, grown in minimal medium supplemented with CS-A as the sole carbon source. The enzyme was purified by ammonium sulphate precipitation followed by serial chromatography on DEAE Trisacryl M, CM Trisacryl M and heparin-agarose. SDS-PAGE analysis of the purified enzyme yielded a single band with a mol.wt of c. 83000. The purified GAG depolymerase was unusual in its substrate specificity. The enzyme was initially regarded as a CS depolymerase because of its induction by CS-A. However, the GAG depolymerase exhibited greatest activity against HA, whereas the degradation rates of CS-A and CS-C were c. 8% and 2%, respectively, of the rate with HA. On this basis the enzyme could be classified as a hyaluronidase rather than a CS depolymerase. The pH optimum was around neutrality and the enzyme was unusual in having a high pI of approximately 9.3.

Isolation and characterization of an induced chondroitinase ABC from Flavobacterium heparinum.

During the investigation of alternative methods for the large scale preparation of chondroitinases AC, B and C from Flavobacterium heparinum, a new chondroitinase activity was observed. This new enzyme, like the other chondroitinases, acts as an eliminase, forming unsaturated sulfated disaccharides from dermatan and chondroitin sulfates. In contrast to the chondroitinases previously described, which are endoglycosidases, this chondroitinase ABC cleaves the glycosidic linkages in an exolytic fashion, beginning at the reducing end of the substrate molecules. The oligosaccharides formed as transient products by the action of either chondroitinases or testicular hyaluronidase upon dermatan and chondroitin sulfates are also rapidly degraded by the chondroitinase ABC, regardless of their size or the presence of delta-4,5 unsaturation in the terminal uronic acid residue. The maximum activity of the chondroitinase ABC occurs at 30 degrees C and at pH 6.0-7.5. Only 15% of the activity was observed at 37 degrees C, indicating that the enzyme is very sensitive to thermal denaturation. It is strongly inhibited by phosphate ions and is also inhibited by the unsaturated disaccharides formed.

Analysis of outer membrane proteins which are associated with growth of Bacteroides thetaiotaomicron on chondroitin sulfate.

By analyzing outer membrane proteins of Bacteroides thetaiotaomicron on two-dimensional polyacrylamide gels, we were able to identify 10 protein spots that were associated with growth on chondroitin sulfate but not with growth on glucuronic acid or other monosaccharides. These proteins were distinct from the outer membrane polypeptides that were associated with growth on two other negatively charged polysaccharides, polygalacturonic acid and heparin. Of the 10 protein spots that were associated with growth on chondroitin sulfate, 4 could be detected on immunoblots with antiserum that had been raised against outer membranes from bacteria grown on chondroitin sulfate and then cross-adsorbed with membranes from bacteria grown on glucose. Synthesis of these four proteins appeared to be regulated coordinately with synthesis of the two enzymes that degrade chondroitin sulfate, chondroitin lyase I and II. Although one of the four proteins (Mr 110,000) was similar in molecular weight to the chondroitin lyases, the cross-adsorbed antiserum which detected this outer membrane protein did not cross-react with either of these two enzymes.

Isolation and characterization of two chondroitin lyases from Bacteroides thetaiotaomicron.

Two chondroitin lyases were isolated from the colon anaerobe Bacteroides thetaiotaomicron. Both enzymes had similar molecular weights (104,000 and 108,000) and similar isoelectric points (8.0 and 7.9, respectively). Both enzymes were active against chondroitin sulfates A, B, and C and unsulfated polysaccharides, such as chondroitin and hyaluronic acid, although one of the enzymes was twice as active against chondroitin as the other enzyme. Both had similar Km values for chondroitin sulfates A and C (40 to 70 micrograms/ml) and for chondroitin (300 to 400 micrograms/ml). Neither enzyme could degrade the highly sulfated mucopolysaccharide heparin, but heparin was a potent inhibitor of the activity of both enzymes. Although enzymes I and II were similar in many respects, a comparison of peptides resulting from partial digestion with N-chlorosuccinimide or papain demonstrated that the two proteins are not related.

Proteinase activity in chondroitin lyase (chondroitinase) and endo-beta-D-galactosidase (keratanase) preparations and a method to abolish their proteolytic effect on proteoglycan.

Significant amounts of proteinase activity have been found in chondroitin ABC lyase (EC 4.2.2.4), chondroitin AC II lyase and endo-beta-D-galactosidase (keratanase) from commercial sources. It would appear, therefore, that certain earlier biochemical and histochemical studies, which employed these commercial enzyme preparations for their presumed ability to degrade only glycosaminoglycans, may require re-evaluation. A mixture of EDTA, N-ethylmaleimide, phenylmethanesulphonyl fluoride and pepstatin abolishes the effect of the contaminating proteinases on proteoglycan with less significant effect on the chondroitin lyase or keratanase activity.

Purification of a mucopolysacharidase from Bacteroides distasonis.

A mucopolysaccharidase derived from a pathogenic strain of Bacteroides distasonis was isolated and purified by fractionation with cold acetone and ion-exchange chromatography on DEAE-cellulose, pH 8.0. Three detectable enzyme activities from concentrated supernatant filtrates were obtained in a fraction precipitated by three volumes of cold acetone; these were DNAase, hyaluronidase and chondroitinase-like activity. Separation of the DNAase was achieved by ion-exchange chromatography. Fractions designated as purified mucopolysaccharidase contained both hyaluronidase and chondroitinase-like activity.

Purification and properties of N-acetylgalactosamine 6-sulphate sulphatase from human placenta.

1. N-Acetylgalactosamine 6-sulphate sulphatase was purified about 20000-fold from the soluble extract of human placenta with N-acetylgalactosamine 6-sulphate-glucuronic acid-N-acetyl[1-(3)H]galactosaminitol 6-sulphate as substrate in the activity assay. The enzyme appears to be a glycoprotein with a mol.wt. of about 100000 as determined by gel filtration. On gel electrophoresis in the presence of sodium dodecyl sulphate the major protein band had a mol.wt. of 78000. Variable charge heterogeneity was observed in several enzyme preparations. 2. The purified enzyme released up to one sulphate molecule from the disulphated trisaccharide. It was active towards N-acetylgalactosamine 6-sulphate and exhibited no measurable N-acetylglucosamine 6-sulphate sulphatase or any other known lysosomal sulphatase activity. Hydrolysis of [1-(3)H]galactitol 6-sulphate was achieved by incubation neither with a crude nor with a purified enzyme preparation. Chondroitin 6-sulphate and keratan sulphate, as well as heparin and heparan sulphate, served as competitive inhibitors of the enzyme. 3. Purified N-acetylgalactosamine 6-sulphate sulphatase activity was optimal at pH4.9 and 4.4 when assayed in 0.02m-sodium acetate buffer and at pH4.2 and 5.2 in 0.1m-sodium acetate buffer. A single pH-optimum at pH4.8 was observed for the crude enzyme and for the purified enzyme after mild periodate treatment. The sulphatase activity was inhibited by a variety of anions and cations and activated by thiol-specific and thiol reagents.

Purification of chondroitinase B and chondroitinase C using glycosaminoglycan-bound AH-Sepharose 4B.

Chondroitinase B and chondroitinase C were separated from an extract of Flavobacterium heparinum induced with chondroitin 6-sulfate by using column chromatography on hydroxylapatite. Chondroitinase C was eluted together with the activities of hyaluronidase, delta4,5glycosiduronase, and sulfatase. The latter two activities were eliminated exclusively by passing the crude chondroitinase C fraction through a phosphono-cellulose column pre-equilibrated with 0.07M sodium phosphate buffer (pH 6.8). Chondroitinase C was then purified by affinity chromatography using dermatan sulfate-bound AH-Sepharose 4B coated with the same glycosaminoglycan. Purification of the enzyme was achieved 18-fold and in 73% yield. On the other hand, the activities of delta4,5glycosiduronase and sulfatase were decreased to 50 and 60%, respectively, as compared with those in the crude chondroitinase B fraction, after passing the fraction through a column of phosphono-cellulose pre-equilibrated with 0.1M sodium phosphate buffer (pH 6.8). The remaining activities of these two enzymes were then eliminated from chondroitinase B by affinity chromatography with heparin-bound AH-Sepharose 4B coated with dermatan sulfate. In the affinity chromatography used in the present study, non-covalent coating of the glycosaminoglycan-bound (covalently) AH-Sepharose 4B with the same or another glycosaminoglycan was found to be important.

Chondroitinase C from Flavobacterium heparinum.

A chondroitinase that acts upon chondroitin sulfate C and hyaluronic acid was isolated from Flavobacterium heparinum. This enzyme was seperated from constitutional chondroitinase AC and an induced chondroitinase B also present in extracts of F. heparinum previously grown in the presence of chondroitin sulfates A, B or C. The enzyme acts upon chondroitin sulfate C producing tetrasaccharide plus an unsaturated 6-sulfated disaccharide (delta Di-6S), and upon hyaluronic acid producing unsaturated nonsulfated disaccharide (delta Di-OS). Chondroitin sulfate A is also degraded producing oligosaccharides and delta Di-6S but not delta Di-4S. The chondroitinase C is also distinguished from the chondroitinases B and AC by several properties, such as effect of ions, temperature for optimal activity, and susceptibility to increasing salt concentrations. The substrate specificity of the chondroitinase C is different from that of any other chondroitinase or hyaluronidase described so far.

A comparative study between a chondroitinase B and a chondroitinase AC from Flavobacterium heparinum: Isolation of a chondroitinase AC-susceptible dodecasaccharide from chondroitin sulphate B.

A chondroitinase that degrades only chondroitin sulphate B was isolated from Flavobacterium heparinum, and separated from a constitutive chondroitinase AC also present in extracts of F. heparinum. The enzyme acts only on chondroitin sulphate B, producing oligo- and tetra-saccharides, plus an unsaturated 4-sulphated disaccharide (deltaDi-4S). The oligosaccharide fraction (mol. wt. 3000) is susceptible to chondroitinase AC, producing mainly deltaDi-4S. The chondroitinase B is distinguished from chondroitinase AC by several properties, such as the effect of certain metal ions, temperature for optimal activity, and susceptibility to increasing salt concentrations. The enzyme is induced in F. heparinum by all the chondroitin sulphates, as well as by the disaccharides prepared from the chondroitins. The mechanism of induction of the enzyme and the structure of chondroitin sulphate B are discussed in relation to these results.