A novel hyaluronidase produced by Bacillus sp. A50

Cloning and characterization of a hyaluronate lyase EsHyl8 from Escherichia sp. A99

Hyaluronidase, an enzyme that degrades hyaluronic acid (HA), is utilized in clinical settings to facilitate drug diffusion, manage extravasation, and address injection-related complications linked to HA-based fillers. In this study, a novel hyaluronate lyase EsHyl8 was cloned, expressed, and characterized from Escherichia sp. A99 of human intestinal origin. This lyase belongs to polysaccharide lyase (PL) family 8, and showed specific activity towards HA. EsHyl8 exhibited optimal degradation at 40 °C and pH 6.0. EsHyl8 exhibited a high activity of 376.32 U/mg among hyaluronidases of human gut microorganisms. EsHyl8 was stable at 37 °C and remained about 70 % of activity after incubation at 37 °C for 24 h, demonstrating excellent thermostability. The activity of EsHyl8 was inhibited by Zn2+, Cu2+, Fe3+, and SDS. EsHyl8 was an endo-type enzyme whose end-product was unsaturated disaccharide. This study enhances our understanding of hyaluronidases from human gut microorganisms.

Identification and Characterization of a Highly Active Hyaluronan Lyase from Enterobacter asburiae

Hyaluronic acid (HA) is a well-known functional marine polysaccharide. The utilization and derivative development of HA are of great interest. Hyaluronan lyase has wide application prospects in the production of HA oligosaccharides and lower molecular weight HA. In this study, a strain of Enterobacter asburiae CGJ001 with high hyaluronan lyase activity was screened from industrial wastewater. This strain exhibited an impressive enzyme activity of 40,576 U/mL after being incubated for 14 h. Whole genome sequencing analysis revealed that E. asburiae CGJ001 contained a cluster of genes involved in HA degradation, transport, and metabolism. A newly identified enzyme responsible for glycosaminoglycan degradation was designated as HylEP0006. A strain of E. coli BL21(DE3)/pET-22b(+)-hylEP0006 was successfully constructed. HylEP0006 exhibited optimal degradation at 40 °C and pH 7.0, showing a high activity of 950,168.3 U/mg. HylEP0006 showed specific activity against HA. The minimum degradation fragment of HylEP0006 was hyaluronan tetrasaccharides, and HylEP0006 could efficiently degrade HA into unsaturated disaccharides (HA2), with HA2 as the final product. These characteristics indicate that HylEP0006 has a potential application prospect for the extraction and utilization of hyaluronic acid.

Purification and characterization of the produced hyaluronidase by Brucella Intermedia MEFS for antioxidant and anticancer applications

Hyaluronidase (hyase) is an endoglycosidase enzyme that degrades hyaluronic acid (HA) and is mostly known to be found in the extracellular matrix of connective tissues. In the current study, eleven bacteria isolates and one actinomycete were isolated from a roaster comb and screened for hyase production. Seven isolates were positive for hyase, and the most potent isolate was selected based on the diameter of the transparent zone. Based on the morphological, physiological, and 16 S rRNA characteristics, the most potent isolate was identified as Brucella intermedia MEFS with accession number OR794010. The environmental conditions supporting the maximum production of hyase were optimized to be incubation at 30 ºC for 48 h and pH 7, which caused a 1.17-fold increase in hyase production with an activity of 84 U/mL. Hyase was purified using a standard protocol, including precipitation with ammonium sulphate, DEAE as ion exchange chromatography, and size exclusion chromatography using Sephacryle S100, with a specific activity of 9.3-fold compared with the crude enzyme. The results revealed that the molecular weight of hyase was 65 KDa, and the optimum conditions for hyase activity were at pH 7.0 and 37 °C for 30 min. The purified hyase showed potent anticancer activities against colon, lung, skin, and breast cancer cell lines with low toxicity against normal somatic cells. The cell viability of hyase-treated cancer cells was found to be in a dose dependent manner. Hyase also controlled the growth factor-induced cell cycle progression of breast cancer cells and caused relative changes in angiogenesis-related genes as well as suppressed many pro-inflammatory proteins in MDA cells compared with 5-fluorouracil, indicating the significant role of hyase as an anticancer agent. In addition, hyase recorded the highest DPPH scavenging activity of 65.49% and total antioxidant activity of 71.84% at a concentration of 200 µg/mL.

Efficient Expression and Characterization of an Endo-Type Lyase HCLase_M28 and Its Gradual Scale-Up Fermentation for the Preparation of Chondroitin Sulfate Oligosaccharides

Glycosaminoglycan (GAG) lyases have been critical in structural and functional studies of GAGs. HCLase_M28, a lyase identified from the genome of Microbacterium sp. M28 was heterologously expressed, enzymatically characterized, and prepared in large-scale fermentation for the production of chondroitin sulfate (CS) oligosaccharides. Results showed that the expression of HCLase_M28 in Escherichia coli BL21 (DE3)-pET24a-HCLase_M28opt1 and Bacillus subtilis W800-pSTOP1622-HCLase_M28opt2 were 108-fold and 25-fold that of wide strain. The optimal lytic reaction of HCLase_M28 happened in 20 mM Tris-HCl (pH 7.2) at 50 °C with a specific activity of 190.9 U/mg toward CS-A. The degrading activity was slightly simulated in presence of 1 mM Ca2+ and Mn2+ while severely inhibited by Hg+, Cu2+, Fe3+, and SDS. TLC and ESI-MS analysis proved HCLase_M28 was an endolytic lyase and degraded CS and hyaluronic acid into unsaturated disaccharides. Through a gradual scale-up of fermentation in 5 L, 100 L, and 1000 L, a highly efficient intracellular expression of HCLase_M28 with an activity of 3.88 × 105 U/L achieved within a 34 h of cultivation. Through ultrafiltration, CS oligosaccharides with DP of 2 to 8 as the main components could be controllably prepared. The successful large-scale fermentation made HCLase_M28 a promising enzyme for industrial production of CS oligosaccharides.

Enzyme Production and Inhibitory Potential of Pseudomonas aeruginosa: Contrasting Clinical and Environmental Isolates

(1) Background: This study summarizes the findings of two studies investigating the inhibitory effects of Pseudomonas aeruginosa strains from clinical and environmental sources against gram-positive and gram-negative bacteria and fungi. The studies also analyzed the correlation between enzyme production and inhibitory effects to gain insights into the antimicrobial capabilities of P. aeruginosa strains; (2) Methods: Both studies employed similar methodologies, including the use of disk diffusion and well diffusion methods to assess the inhibitory effects of P. aeruginosa strains against target pathogens. Enzyme production was analyzed through various biochemical assays to determine the diversity and frequencies of enzyme secretion among the strains; (3) Results: A comparative analysis of enzyme production in P. aeruginosa strains from clinical sources revealed significant variations in enzyme production, with hemolysin and protease being the most commonly produced enzymes. Gelatinase production showed lower rates, whereas chondroitinase and hyaluronidase were absent or occurred less frequently. In contrast, a comparative analysis of enzyme production in environmental isolates showed different patterns, indicating adaptation to environmental conditions. Pyocyanin production was absent in all environmental isolates. The inhibitory effects against gram-positive and gram-negative bacteria varied among different P. aeruginosa strains, with strain-specific variations observed. Limited inhibitory effects were observed against fungi, primarily toward gram-positive bacteria; (4) Conclusions: The findings highlight the strain-specific nature of inhibitory effects and enzyme production in P. aeruginosa strains. The correlation between enzyme production and inhibitory effects against gram-positive bacteria suggest a potential role of specific enzymes, such as hemolysin and protease, in the antimicrobial activity. The complexity of the relationship between enzyme production and the inhibition of different pathogens requires further investigation. The results emphasize the potential of P. aeruginosa strains as sources for antimicrobial strategies, particularly against gram-positive bacteria. Future research should focus on understanding the mechanisms underlying these inhibitory effects and exploring their therapeutic applications.

Biodegradable Hydrogels Based on Chitosan and Pectin for Cisplatin Delivery

Preparation of stable hydrogels using physically (electrostatically) interacting charge-complementary polyelectrolyte chains seems to be more attractive from a practical point of view than the use of organic crosslinking agents. In this work natural polyelectrolytes-chitosan and pectin-were used, due to their biocompatibility and biodegradability. The biodegradability of hydrogels is confirmed by experiments with hyaluronidase as an enzyme. It has been shown that the use of pectins with different molecular weights makes it possible to prepare hydrogels with different rheological characteristics and swelling kinetics. These polyelectrolyte hydrogels loaded with cytostatic cisplatin as a model drug provide an opportunity for its prolonged release, which is important for therapy. The drug release is regulated to a certain extent by the choice of hydrogel composition. The developed systems can potentially improve the effects of cancer treatment due to the prolonged release of cytostatic cisplatin.

Study on the preparation and biological activities of low molecular weight squid ink polysaccharide from Sepiella maindroni

Sepiella maindroni ink polysaccharide (SIP) from the ink of cuttlefish Sepiella maindroni and its sulfated derivative (SIP-SII) have been demonstrated to possess diverse biological activities. But little is known about low molecular weight squid ink polysaccharides (LMWSIPs). In this study, LMWSIPs were prepared by acidolysis, and the fragments with molecular weight (M_w) distribution in the ranges of 7 kDa to 9 kDa, 5 kDa to 7 kDa and 3 kDa to 5 kDa were grouped and named as LMWSIP-1, LMWSIP-2 and LMWSIP-3, respectively. The structural features of LMWSIPs were elucidated, and their anti-tumor, antioxidant and immunomodulatory activities were also studied. The results showed that with the exception of LMWSIP-3, the main structures of LMWSIP-1 and LMWSIP-2 did not change compared with SIP. Though there were no significant differences in the antioxidant capacity between LMWSIPs and SIP, the anti-tumor and immunomodulatory activities of SIP were enhanced to a certain extent after degradation. It is particularly noteworthy that the activities of LMWSIP-2 in anti-proliferation, promoting apoptosis and inhibiting migration of tumor cells as well as promoting the proliferation of spleen lymphocytes were significantly higher than those of SIP and the other degradation products, which is promising in the anti-tumor pharmaceutical field.

Cloning and Biochemical Characterization of a Hyaluronate Lyase from Bacillus sp. CQMU-D

Hyaluronidase (HAase) can enhance drug diffusion and dissipate edema by degrading hyaluronic acid (HA) in the extracellular matrix into unsaturated HA oligosaccharides in mammalian tissues. Microorganisms are recognized as valuable sources of HAase. In this study, a new hyaluronate lyase (HAaseD) from Bacillus sp. CQMU-D was expressed in Escherichia coli BL21, purified, and characterized. The results showed that HAaseD belonged to the polysaccharide lyase (PL) 8 family and had a molecular weight of 123 kDa. HAaseD could degrade chondroitin sulfate (CS) -A, CS-B, CS-C, and HA, with the highest activity toward HA. The optimum temperature and pH value of HAaseD were 40°C and 7.0, respectively. In addition, HAaseD retained stability in an alkaline environment and displayed higher activity with appropriate concentrations of metal ions. Moreover, HAaseD was an endolytic hyaluronate lyase that could degrade HA to produce unsaturated HA oligosaccharides. Together, our findings indicate that HAaseD from Bacillus sp. CQMU-D is a new hyaluronate lyase and with excellent potential for application in industrial production.

A heterodimeric hyaluronate lyase secreted by the activated sludge bacterium Haliscomenobacter hydrossis

Haliscomenobacter hydrossis is a filamentous bacterium common in activated sludge. The bacterium was found to utilize hyaluronic acid, and hyaluronate lyase activity was detected in its culture. However, no hyaluronate lyase gene was found in the genome, suggesting the bacterium secretes a novel hyaluronate lyase. The purified enzyme exhibited two bands on SDS-PAGE and a single peak on gel filtration chromatography, suggesting a heterodimeric composition. N-terminal amino acid sequence and mass spectrometric analyses suggested that the subunits are molybdopterin-binding and [2Fe-2S]-binding subunits of a xanthine oxidase family protein. The presence of the cofactors was confirmed using spectrometric analysis. Oxidase activity was not detected, revealing that the enzyme is not an oxidase but a hyaluronate lyase. Nuclear magnetic resonance analysis of the enzymatic digest revealed that the enzyme breaks hyaluronic acid to 3-(4-deoxy-β-d-gluc-4-enuronosyl)-N-acetyl-d-glucosamine. As hyaluronate lyases (EC 4.2.2.1) are monomeric or trimeric, the enzyme is the first heterodimeric hyaluronate lyase.

Hyaluronic acid association with bacterial, fungal and viral infections: Can hyaluronic acid be used as an antimicrobial polymer for biomedical and pharmaceutical applications?

The relationships between hyaluronic acid (HA) and pathological microorganisms incite new understandings on microbial infection, tissue penetration, disease progression and lastly, potential treatments. These understandings are important for the advancement of next generation antimicrobial therapeutical strategies for the control of healthcare-associated infections. Herein, this review will focus on the interplay between HA, bacteria, fungi, and viruses. This review will also comprehensively detail and discuss the antimicrobial activity displayed by various HA molecular weights for a variety of biomedical and pharmaceutical applications, including microbiology, pharmaceutics, and tissue engineering.

Absorption, metabolism, and functions of hyaluronic acid and its therapeutic prospects in combination with microorganisms: A review

Hyaluronic acid (HA) is key to the stability of the internal environment of tissues. HA content in tissues gradually decreases with age, causing age-related health problems. Exogenous HA supplements are used to prevent or treat these problems including skin dryness and wrinkles, intestinal imbalance, xerophthalmia, and arthritis after absorption. Moreover, some probiotics are able to promote endogenous HA synthesis and alleviate symptoms caused by HA loss, thus introducing potential preventative or therapeutic applications of HA and probiotics. Here, we review the oral absorption, metabolism, and biological function of HA as well as the potential role of probiotics and HA in increasing the efficacy of HA supplements.

Targeted Depletion of Hyaluronic Acid Mitigates Murine Breast Cancer Growth

Hyaluronic acid (HA) is highly elevated in breast cancers compared to normal breast tissue and is associated with increased tumor aggressiveness and poor prognosis. HA interacts with cell-trafficking CD44 receptors to promote tumor cell migration and proliferation and regulates both pro- and anti-inflammatory cytokine production through tumor-associated macrophages. The highly negative charge of HA enables its uptake of vast amounts of water that greatly increases the tumor interstitial fluidic pressure, which, combined with the presence of other extracellular matrix components such as collagen, results in tumor stroma with abnormal vasculature, hypoxia, and increased drug resistance. Thus, the degradation of HA in breast cancer may attenuate growth and improve permeability to anticancer agents. Previous methods to deplete tumor HA have resulted in significant off-tumor effects due to the systemic use of mammalian hyaluronidases. To overcome this, we developed a hyaluronidase-secreting Salmonella typhimurium (YS-HAse) that specifically and preferentially colonizes tumors to deplete HA. We show that the systemic administration of YS-HAse in immunocompetent murine models of breast cancer enhances tumor perfusion, controls tumor growth, and restructures the tumor immune contexture. These studies highlight the utility of YS-HAse as a novel microbial-based therapeutic that may also be combined with existing therapeutic approaches.

Insights into the source, mechanism and biotechnological applications of hyaluronidases

It has long been found that hyaluronidases exist in a variety of organisms, playing their roles in various biological processes including infection, envenomation and metabolic regulation through degrading hyaluronan. However, exploiting them as a bioresource for specific applications had not been extensively studied until the latest decades. In recent years, new application scenarios have been developed, which extended the field of application, and emphasized the research value of hyaluronidase. This critical review comprehensively summarizes existing studies on hyaluronidase from different source, particularly in their structures, action patterns, and biological functions in human and mammals. Furthermore, we give in-depth insight into the resource mining and protein engineering process of hyaluronidase, as well as strategies for their high-level production, indicating that mixed strategies should be adopted to obtain well-performing hyaluronidase with efficiency. In addition, advances in application of hyaluronidase were summarized and discussed. Finally, prospects for future researches are proposed, highlighting the importance of further investigation into the characteristics of hyaluronidases, and the necessity of investigating their products for the development of their application value.

Biochemical and Molecular Characteristics of a Novel Hyaluronic Acid Lyase from Citrobacter freundii

The Gram-negative strain of Citrobacter freundii, YNLX, has the ability to degrade hyaluronic acid. In this study, we expressed a C. freundii hyaluronic acid lyase, from polysaccharide lyase family 8, in Escherichia coli. The purified recombinant enzyme (rHynACF8) showed a substantially higher cleavage activity of hyaluronic acid than chondroitin sulfate. We found that its optimal pH and temperature are 5.5 and 35 °C, respectively. In addition, the enzyme activity was not notably affected by most metal ions. Km and kcat of rHynACF8 towards HA were 1.5 ± 0.01 mg/mL and 30.9 ± 0.5 /s, respectively. rHynACF8 is an endo-acting enzyme. Its cleavage products had dramatically increased antioxidant activity than hyaluronic acid in vitro (p < 0.001). As the molecular weight of hyaluronic acid decreased, the intramolecular interactions among antioxidant functional groups were removed; in the process of the cracking reaction, new double bonds formed and conjugated with the carbonyl group. We presumed that the structural change is the critical factor influencing antioxidant capacity. Overall, we found that rHynACF8 from Gram-negative bacteria with metal ion resistance, indicated the relationship between the function and structure of its antioxidant cleavage product.

β-elimination of hyaluronate by red king crab hyaluronidase

Crustacean hyaluronidases are poorly understood both in terms of their enzymatic properties and in terms of their structural features. In this work, we show that the hepatopancreas homogenate of the red king crab has a hyaluronidase activity that is an order of magnitude higher than its commercial counterpart. Zymography revealed that the molecular weight of a protein with hyalorunidase activity is 40-50 kDa. Analysis of the hepatopancreas transcriptome and results of cloning and sequencing of cDNA revealed a hyaluronidase sequence with an expected molecular weight of 42.5 kDa. Further analysis showed that hyaluronat enzymatic cleavage follows the [Formula: see text]-elimination mechanism, which is well known for bacterial hyaluronidases. The results of ion-exchange chromatography showed that the final product of hyaluronate degradation is unsaturated tetrasaccharide. Thus, we identified a new hyaluronidase of higher eukaryotes, which is not integrated into the modern classification of hyaluronidases.

Hyaluronidases and hyaluronate lyases: From humans to bacteriophages

Hyaluronan is a non-sulfated negatively-charged linear polymer distributed in most parts of the human body, where it is located around cells in the extracellular matrix of connective tissues and plays an essential role in the organization of tissue architecture. Moreover, hyaluronan is involved in many biological processes and used in many clinical, cosmetic, pharmaceutic, and biotechnological applications worldwide. As interest in hyaluronan applications increases, so does interest in hyaluronidases and hyaluronate lyases, as these enzymes play a major part in hyaluronan degradation. Many hyaluronidases and hyaluronate lyases produced by eukaryotic cells, bacteria, and bacteriophages have so far been described and annotated, and their ability to cleave hyaluronan has been experimentally proven. These enzymes belong to several carbohydrate-active enzyme families, share very low sequence identity, and differ in their cleaving mechanisms and in their structural and functional properties. This review presents a summary of annotated and characterized hyaluronidases and hyaluronate lyases isolated from different sources belonging to distinct protein families, with a main focus on the binding and catalytic residues of the discussed enzymes in the context of their biochemical properties. In addition, the application potential of individual groups of hyaluronidases and hyaluronate lyases is evaluated.

Characterization of a Hyaluronic Acid Utilization Locus and Identification of Two Hyaluronate Lyases in a Marine Bacterium Vibrio alginolyticus LWW-9

Hyaluronic acid (HA) is a negatively charged and linear polysaccharide existing in the tissues and body fluids of all vertebrates. Some pathogenic bacteria target hyaluronic acid for adhesion and/or infection to host cells. Vibrio alginolyticus is an opportunistic pathogen related to infections of humans and marine animals, and the hyaluronic acid-degrading potential of Vibrio spp. has been well-demonstrated. However, little is known about how Vibrio spp. utilize hyaluronic acid. In this study, a marine bacterium V. alginolyticus LWW-9 capable of degrading hyaluronic acid has been isolated. Genetic and bioinformatic analysis showed that V. alginolyticus LWW-9 harbors a gene cluster involved in the degradation, transport, and metabolism of hyaluronic acid. Two novel PL8 family hyaluronate lyases, VaHly8A and VaHly8B, are the key enzymes for the degradation of hyaluronic acid. VaHly8A and VaHly8B have distinct biochemical properties, reflecting the adaptation of the strain to the changing parameters of the aquatic habitats and hosts. Based on genomic and functional analysis, we propose a model for the complete degradation of hyaluronic acid by V. alginolyticus LWW-9. Overall, our study expands our knowledge of the HA utilization paradigm within the Proteobacteria, and the two novel hyaluronate lyases are excellent candidates for industrial applications.

Current advances in the biosynthesis of hyaluronic acid with variable molecular weights

Hyaluronic acid (HA) is a naturally formed acidic mucopolysaccharide, with excellent moisturising properties and used widely in the medicine, cosmetics, and food industries. The industrial production of specific molecular weight HA has become imperative. Different biological activities and physiological functions of HA mainly depend on the degree of polymerisation. This article reviews the research status and development prospects of the green biosynthesis and molecular weight regulation of HA. There is an application-based prerequisite of specific molecular weight of HA that could be regulated either during the fermentation process or via a controlled HA degradation process. This work provides an important theoretical basis for the downstream efficient production of diversified HA, which will further accelerate the research applications of HA and provide a good scientific basis and method reference for the study of the molecular weight regulation of similar biopolymers.

Research and Application of Chondroitin Sulfate/Dermatan Sulfate-Degrading Enzymes

Chondroitin sulfate (CS) and dermatan sulfate (DS) are widely distributed on the cell surface and in the extracellular matrix in the form of proteoglycan, where they participate in various biological processes. The diverse functions of CS/DS can be mainly attributed to their high structural variability. However, their structural complexity creates a big challenge for structural and functional studies of CS/DS. CS/DS-degrading enzymes with different specific activities are irreplaceable tools that could be used to solve this problem. Depending on the site of action, CS/DS-degrading enzymes can be classified as glycosidic bond-cleaving enzymes and sulfatases from animals and microorganisms. As discussed in this review, a few of the identified enzymes, particularly those from bacteria, have wildly applied to the basic studies and applications of CS/DS, such as disaccharide composition analysis, the preparation of bioactive oligosaccharides, oligosaccharide sequencing, and potential medical application, but these do not fulfill all of the needs in terms of the structural complexity of CS/DS.

Biochemical characterization of a thermophilic hyaluronate lyase TcHly8C from Thermasporomyces composti DSM22891

Hyaluronic acid (HA) is an anionic linear polysaccharide abundantly distributed in the extracellular matrix of mammalian connective, growing, and tumor tissues. Hyaluronidase is used as an important drug diffusion promoter and a tool enzyme to produce HA oligosaccharides. However, there is no thermostable hyaluronidase suitable for application to date. In this study, a thermophilic hyaluronate lyase, TcHly8C, from Thermasporomyces composti DSM22891 was expressed in Escherichia coli. The recombinant TcHly8C was most active at 70 °C, and it retained about 30% of initial activity after incubation at 60 °C for 28 days. The half-lives of TcHly8C at 60 °C and 70 °C were 16.1 d and 2.3 h, respectively. The optimum pH of TcHly8C is 5.93, and it was stable at pH 6.15-10.90. The presence of Mg²⁺ could enhance its enzymatic activity significantly. K_m, k_cat, and k_cat/K_m of TcHly8C towards HA were 3.69 mg∙ml^-1, 17.82 s^-1, and 4.82 ml∙mg^-1∙s^-1, respectively. TcHly8C degraded HA in an exolytic mode, and the end product was unsaturated HA disaccharide (ΔUA-GlcNAc). Overall, our results show that TcHly8C is the first reported PL8 exo-type hyaluronate lyase with high thermostability, which provides a potential enzyme used in medicine and production of HA oligosaccharides.

Cloning, Expression, and Characterization of a New Glycosaminoglycan Lyase from Microbacterium sp. H14

Glycosaminoglycan (GAG) lyase is an effective tool for the structural and functional studies of glycosaminoglycans and preparation of functional oligosaccharides. A new GAG lyase from Microbacterium sp. H14 was cloned, expressed, purified, and characterized, with a molecular weight of approximately 85.9 kDa. The deduced lyase HCLaseM belonged to the polysaccharide lyase (PL) family 8. Based on the phylogenetic tree, HCLaseM could not be classified into the existing three subfamilies of this family. HCLaseM showed almost the same enzyme activity towards hyaluronan (HA), chondroitin sulfate A (CS-A), CS-B, CS-C, and CS-D, which was different from reported GAG lyases. HCLaseM exhibited the highest activities to both HA and CS-A at its optimal temperature (35 °C) and pH (pH 7.0). HCLaseM was stable in the range of pH 5.0–8.0 and temperature below 30 °C. The enzyme activity was independent of divalent metal ions and was not obviously affected by most metal ions. HCLaseM is an endo-type enzyme yielding unsaturated disaccharides as the end products. The facilitated diffusion effect of HCLaseM is dose-dependent in animal experiments. These properties make it a candidate for further basic research and application.

Purification of hyaluronidase as an anticancer agent inhibiting CD44

Hyaluronidase (Hyal) can be employed to accomplish a diversity of complications related to hyaluronic acid (HA). Hyal contains some classes of catalysts that cleave HA. This enzyme is detected in several human tissues as well as in animal venoms, pathogenic organisms and cancers. Destructive cancer cells regularly increase the CD44 receptor existing in a cell membrane. This receptor acts as an exact receptor for HA, and HA is recognized to motivate the migration, spread, attack and metastasis of cancer cells. Nearly all of the methods used to purify Hyal are highly costly and not proper for industrial applications. This survey aims to review different methods of Hyal purification, which acts as an anticancer agent by degrading HA in tissues and thus inhibiting the CD44-HA interaction. Hyal can be successfully employed in the management of cancer, which is associated with HA-CD44. This review has described different methods for Hyal purification to prepare an origin to develop a novel purification technique for this highly appreciated protein. Using multiple columns is not applicable for the purification of Hyal and thus cannot be used at the industrial level. It is better to use affinity chromatography of anti-Hyal for Hyal with one-step purification.

Cloning and Characterization of a Chondroitin AC Exolyase from Arthrobacter sp. SD-04

Glycosaminoglycans (GAGs) and their low-molecular weight derivates have received considerable interest in terms of their potential clinical applications, and display a wide variety of pharmacological and pharmacokinetic properties. Structurally distinct GAG chains can be prepared by enzymatic depolymerization. A variety of bacterial chondroitin sulfate (CS) lyases have been identified, and have been widely used as catalysts in this process. Here, we identified a putative chondroitin AC exolyase gene, AschnAC, from an Arthrobacter sp. strain found in a CS manufacturing workshop. We expressed the enzyme, AsChnAC, recombinantly in Escherichia coli, then purified and characterized it in vitro. The enzyme indeed displayed exolytic cleavage activity toward HA and various CSs. Removing the putative N-terminal secretion signal peptide of AsChnAC improved its expression level in E. coli while maintaining chondroitin AC exolyase activity. This novel catalyst exhibited its optimal activity in the absence of added metal ions. AsChnAC has potential applications in preparation of low-molecular weight GAGs, making it an attractive catalyst for further investigation.

Affinity adsorption of bovine hyaluronidase with ligands targeting to active site

Four affinity ligands were designed from 6-chloromethyluracil and 2-aminobenzimidazole and simulated for the interaction with bovine hyaluronidase-1. Regarding sequence alignment, bovine hyaluronidase-1 precursor showed circa 83.6% similarity with human hyaluronidase-1. Regarding structural modeling and molecular docking, bovine hyaluronidase-1 interacted with ligands in the active site. Using epichlorohydrin, 1,3-propanediamine and cyanuric chloride as spacers, 6-chloromethyluracil and 2-aminobenzimidazole were composed to Sepharose beads. The modified Sepharose beads were then subjected to adsorption analysis with bovine hyaluronidase. After one step of affinity adsorption, the samples extracted from bovine testes were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and activity assay. As calculated, the densities of four ligands on sorbents (entitled as L-1, L-2, L-3 and L-4) were 37.7 ± 2.3, 36.4 ± 3.2, 42.4 ± 4.2 and 33.7 ± 2.3 μmol/g wet gel; the theoretical maximum adsorption (Q_max) of bovine hyaluronidase on the four sorbents were 63.6 ± 1.6, 72.0 ± 0.7, 111.0 ± 4.1 and 121.7 ± 2.3 mg/g wet gel, respectively; the dissociation constants (K_d) of the four sorbents were 18.5 ± 0.8, 48.1 ± 4.3, 35.0 ± 3.0, 40.6 ± 2.7 μg/g wet gel, respectively. After optimization, the proteins captured by sorbents attaching 2-aminobenzimidazole based ligands (L-3 and L-4) revealed the main single band at approximately 50 kDa, and the purities were about 85.2 and 96.4%; the bioactivity recoveries were 83.5 and 89.4%. In addition, the bands on SDS-PAGE gel were also extracted and confirmed with linear trap quadropole mass spectrometry (LTQ-MS) analysis.

Can Hyaluronidase Be an Alternative Postoperative Anti-edema Agent to Dexamethasone? Preliminary Results of an Animal Study

PURPOSE

Recombinant human hyaluronidase (rHuPH20) is widely used as a spreading factor, which enhances the absorption of subcutaneously injected medicines. The anti-inflammatory and anti-edema effects of the enzyme were demonstrated in previous studies. In the present study, the anti-edema effect of rHuPH20 was compared with that of dexamethasone in a traumatic rat paw edema model.

MATERIALS AND METHODS

Twenty-four Sprague-Dawley rats (weight 200 to 450 g) were divided into 3 groups: control (group 1), rHuPH20 (group 2), and dexamethasone (group 3). Traumatic edema was induced in the right hind paws of the rats using Feeney's weight-drop model. After edema induction, 0.4 mL of rHuPH20 (100 U/kg = 0.88 μg/kg dose) and 0.4 mL of dexamethasone (0.5 mg/kg dose) were injected into the right hind paws of the rats in groups 2 and 3. The paw volumes were measured before edema induction and at 3, 6, 12, 24, 48, and 72 hours after induction using a plethysmometer. The Mann-Whitney U test was used for the statistical analyses. Probabilities < .05 were accepted as statistically significant.

RESULTS

The between percentage change in the edema mean values of groups 1 and 3 showed no significant difference at all time points; however, group 2 showed significantly less change in the edema mean values at 3, 6, 12, 24, and 48 hours after edema induction (P < .05) compared with group 1. The change in the edema mean value for group 2 was significantly less than that for group 3 at 3, 6, 12, 24, and 48 hours after edema induction (P < .05).

CONCLUSIONS

Local rHuPH20 injection more effectively reduced the edema that was induced traumatically in rat paws than did dexamethasone. However, further clinical studies are needed regarding the use of rHuPH20 as a postoperative anti-edema agent in place of dexamethasone.

Hyaluronate lyase of a deep-sea Bacillus niacini

A hyaluronate lyase (BniHL) was purified to homogeneity from a culture of a deep-sea Bacillus niacin strain JAM F8. The molecular mass of purified BniHL was approximately 120 kDa. The purified enzyme degraded hyaluronan as well as chondroitin sulfates A and C by a β-elimination mechanism. The optimal pH and temperature were around pH 6 and 45 °C for hyaluronan degradation. The enzyme required optimally 2, 50, and 100 mM calcium ions for degradation of hyaluronan, chondroitin sulfate C, and chondroitin sulfate A, respectively. Calcium ions slightly increased the thermal stability of the enzyme. In a genome analysis of strain JAM F8, a BniHL coding gene was identified on the bases of the molecular mass and N-terminal and internal amino acid sequences. The gene consisted of 3411 nucleotides and coded 1136 amino acids. The deduced amino acid sequence showed the highest similarity to the hyaluronate lyase of a Bacillus sp. A50 with 89 % identity.

Constructing a recombinant hyaluronic acid biosynthesis operon and producing food-grade hyaluronic acid in Lactococcus lactis

Hyaluronic acid (HA), a natural high molecular weight polysaccharide, is produced by Streptococcus zooepidemicus. However, Streptococcus has several drawbacks including its potential to produce exotoxins, so there is demand for an alternative HA source. Here, a recombinant HA biosynthesis operon, as well as the HA biosynthesis operon of S. zooepidemicus were introduced into L. lactis using the nisin-controlled expression system, respectively. HA was successfully synthesized by recombinant L. lactis. Furthermore, overexpression of the endogenous enzymes directing the synthesis of precursor sugars was effective at increasing HA production, and increasing the supply of UDP-activated monosaccharide donors aided synthesis of monodisperse HA polysaccharides. Besides GRAS host strain (L. lactis) and NICE system, the selecting marker (lacF gene) of the recombinant strain is also food grade. Therefore, HA produced by recombinant L. lactis overcomes the problems associated with Streptococcus and provides a source of food-grading HA appropriate for widespread biotechnological applications.

Draft Genome Sequence of a Deep-Sea Bacterium, Bacillus niacini Strain JAM F8, Involved in the Degradation of Glycosaminoglycans

Here, we report the draft genome sequence of Bacillus niacini JAM F8, which was newly isolated from deep-sea sediment at a depth of 2,759 m from the Izu-Ogasawara Trench. An array of genes related to degradation of glycosaminoglycans in this bacterium was identified by whole-genome analysis.

Mutual exclusivity of hyaluronan and hyaluronidase in invasive group A Streptococcus

A recent analysis of group A Streptococcus (GAS) invasive infections in Australia has shown a predominance of M4 GAS, a serotype recently reported to lack the antiphagocytic hyaluronic acid (HA) capsule. Here, we use molecular genetics and bioinformatics techniques to characterize 17 clinical M4 isolates associated with invasive disease in children during this recent epidemiology. All M4 isolates lacked HA capsule, and whole genome sequence analysis of two isolates revealed the complete absence of the hasABC capsule biosynthesis operon. Conversely, M4 isolates possess a functional HA-degrading hyaluronate lyase (HylA) enzyme that is rendered nonfunctional in other GAS through a point mutation. Transformation with a plasmid expressing hasABC restored partial encapsulation in wild-type (WT) M4 GAS, and full encapsulation in an isogenic M4 mutant lacking HylA. However, partial encapsulation reduced binding to human complement regulatory protein C4BP, did not enhance survival in whole human blood, and did not increase virulence of WT M4 GAS in a mouse model of systemic infection. Bioinformatics analysis found no hasABC homologs in closely related species, suggesting that this operon was a recent acquisition. These data showcase a mutually exclusive interaction of HA capsule and active HylA among strains of this leading human pathogen.

A novel eliminase from a marine bacterium that degrades hyaluronan and chondroitin sulfate

Lyases cleave glycosaminoglycans (GAGs) in an eliminative mechanism and are important tools for the structural analysis and oligosaccharide preparation of GAGs. Various GAG lyases have been identified from terrestrial but not marine organisms even though marine animals are rich in GAGs with unique structures and functions. Herein we isolated a novel GAG lyase for the first time from the marine bacterium Vibrio sp. FC509 and then recombinantly expressed and characterized it. It showed strong lyase activity toward hyaluronan (HA) and chondroitin sulfate (CS) and was designated as HA and CS lyase (HCLase). It exhibited the highest activities to both substrates at pH 8.0 and 0.5 m NaCl at 30 °C. Its activity toward HA was less sensitive to pH than its CS lyase activity. As with most other marine enzymes, HCLase is a halophilic enzyme and very stable at temperatures from 0 to 40 °C for up to 24 h, but its activity is independent of divalent metal ions. The specific activity of HCLase against HA and CS reached a markedly high level of hundreds of thousands units/mg of protein under optimum conditions. The HCLase-resistant tetrasaccharide Δ(4,5)HexUAα1-3GalNAc(6-O-sulfate)β1-4GlcUA(2-O-sulfate)β1-3GalNAc(6-O-sulfate) was isolated from CS-D, the structure of which indicated that HCLase could not cleave the galactosaminidic linkage bound to 2-O-sulfated d-glucuronic acid (GlcUA) in CS chains. Site-directed mutagenesis indicated that HCLase may work via a catalytic mechanism in which Tyr-His acts as the Brønsted base and acid. Thus, the identification of HCLase provides a useful tool for HA- and CS-related research and applications.