Chondroitin Sulfate Lyases: Applications in Analysis and Glycobiology

Controlled Drug Release from Nanoengineered Polysaccharides

Polysaccharides are naturally occurring complex molecules with exceptional physicochemical properties and bioactivities. They originate from plant, animal, and microbial-based resources and processes and can be chemically modified. The biocompatibility and biodegradability of polysaccharides enable their increased use in nanoscale synthesis and engineering for drug encapsulation and release. This review focuses on sustained drug release studies from nanoscale polysaccharides in the fields of nanotechnology and biomedical sciences. Particular emphasis is placed on drug release kinetics and relevant mathematical models. An effective release model can be used to envision the behavior of specific nanoscale polysaccharide matrices and reduce impending experimental trial and error, saving time and resources. A robust model can also assist in translating from in vitro to in vivo experiments. The main aim of this review is to demonstrate that any study that establishes sustained release from nanoscale polysaccharide matrices should be accompanied by a detailed analysis of drug release kinetics by modeling since sustained release from polysaccharides not only involves diffusion and degradation but also surface erosion, complicated swelling dynamics, crosslinking, and drug-polymer interactions. As such, in the first part, we discuss the classification and role of polysaccharides in various applications and later elaborate on the specific pharmaceutical processes of polysaccharides in ionic gelling, stabilization, cross-linking, grafting, and encapsulation of drugs. We also document several drug release models applied to nanoscale hydrogels, nanofibers, and nanoparticles of polysaccharides and conclude that, at times, more than one model can accurately describe the sustained release profiles, indicating the existence of release mechanisms running in parallel. Finally, we conclude with the future opportunities and advanced applications of nanoengineered polysaccharides and their theranostic aptitudes for future clinical applications.

Heterologous production of chondroitin

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Chondroitin sulfate (CS) is a glycosaminoglycan with a growing variety of applications.

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CS can be produced from microbial fermentation of native or engineered strains.

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Synthetic biology tools are being used to improve CS yields in different hosts.

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Integrated polymerization and sulfation can generate cost-effective CS.

Chondroitin sulfate (CS) is a glycosaminoglycan with a broad range of applications being a popular dietary supplement for osteoarthritis. Usually, CS is extracted from animal sources. However, the known risks of animal products use have been driving the search for alternative methods and sources to obtain this compound. Several pathogenic bacteria naturally produce chondroitin-like polysaccharides through well-known pathways and, therefore, have been the basis for numerous studies that aim to produce chondroitin using non-pathogenic hosts. However, the yields obtained are not enough to meet the high demand for this glycosaminoglycan. Metabolic engineering strategies have been used to construct improved heterologous hosts. The identification of metabolic bottlenecks and regulation points, and the screening for efficient enzymes are key points for constructing microbial cell factories with improved chondroitin yields to achieve industrial CS production. The recent advances on enzymatic and microbial strategies to produce non-animal chondroitin are herein reviewed. Challenges and prospects for future research are also discussed.

A novel chondroitin AC lyase from Pedobacter xixiisoli: Cloning, expression, characterization and the application in the preparation of oligosaccharides

Chondroitin AC lyase can efficiently hydrolyze chondroitin sulfate (CS) to low molecule weight chondroitin sulfate, which has been widely used in clinical therapy, including anti-tumor, anti-oxidation, hypolipidemic, and anti-inflammatory. In this work, a novel chondroitin AC lyase from Pedobacter xixiisoli (PxchonAC) was cloned and overexpressed in Escherichia coli BL21 (DE3). The characterization of PxchonAC showed that it has specific activities on chondroitin sulfate A, Chondroitin sulfate C and hyaluronic acid with 428.77, 270.57, and 136.06 U mg^-1, respectively. The K_m and V_max of PxchonAC were 0.61 mg mL^-1 and 670.18 U mg^-1 using chondroitin sulfate A as the substrate. The enzyme had a half-life of roughly 660 min at 37 °C in the presence of Ca²⁺ and remained a residual activity of 54 % after incubated at 4 °C for 25 days. Molecular docking revealed that Asn123, His223, Tyr232, Arg286, Arg290, Asn372, and Glu374 were mainly involved in the substrate binding. The enzymatic hydrolysis product was analyzed by gel permeation chromatography, demonstrating PxchonAC could hydrolyze CS efficiently.

Engineering a thermostable chondroitinase for production of specifically distributed low-molecular-weight chondroitin sulfate

Chondroitinase ABC I (csABC I) has attracted intensive attention because of its great potential in heparin refining and the enzymatic preparation of low-molecular-weight chondroitin sulfate (LMW-CS). However, low thermal resistance (<30℃) restricts its applications. Herein, structure-guided and sequence-assisted combinatorial engineering approaches were applied to improve the thermal resistance of Proteus vulgaris csABC I. By integrating the deletion of the flexible fragment R166-L170 at the N-terminal domain and the mutation of E694P at the C-terminal domain, variant NΔ5/E694P exhibited 247-fold improvement of its half-life at 37℃ and a 2.3-fold increase in the specific activity. Through batch fermentation in a 3-L fermenter, the expression of variant NΔ5/E694P in an Escherichia coli host reached 1.7 g L^-1 with the activity of 1.0 × 10⁵ U L^-1 . Finally, the enzymatic approach for the preparation of LMW-CS was established. By modulating enzyme concentration and controlling depolymerization time, specifically distributed LMW-CS (7000, 3400, and 1900 Da) with low polydispersity was produced, demonstrating the applicability of these processes for the industrial production of LMW-CS in a more environmentally friendly way.

Polysaccharides; Classification, Chemical Properties, and Future Perspective Applications in Fields of Pharmacology and Biological Medicine (A Review of Current Applications and Upcoming Potentialities)

Polysaccharides are essential macromolecules which almost exist in all living forms, and have important biological functions, they are getting more attention because they exhibit a wide range of biological and pharmacological activities, such as anti-tumour, immunomodulatory, antimicrobial, antioxidant, anticoagulant, antidiabetic, antiviral, and hypoglycemia activities, making them one of the most promising candidates in biomedical and pharmaceutical fields. Polysaccharides can be obtained from many different sources, such as plants, microorganisms, algae, and animals. Due to their physicochemical properties, they are susceptible to physical and chemical modifications leading to enhanced properties, which is the basic concept for their diverse applications in biomedical and pharmaceutical fields. In this review, we will give insight into the most recent updated applications of polysaccharides and their potentialities as alternatives for traditional and conventional therapies. Challenges and limitations for polysaccharides in pharmaceutical utilities are discussed as well.

Aggrecan, the Primary Weight-Bearing Cartilage Proteoglycan, Has Context-Dependent, Cell-Directive Properties in Embryonic Development and Neurogenesis: Aggrecan Glycan Side Chain Modifications Convey Interactive Biodiversity

This review examines aggrecan's roles in developmental embryonic tissues, in tissues undergoing morphogenetic transition and in mature weight-bearing tissues. Aggrecan is a remarkably versatile and capable proteoglycan (PG) with diverse tissue context-dependent functional attributes beyond its established role as a weight-bearing PG. The aggrecan core protein provides a template which can be variably decorated with a number of glycosaminoglycan (GAG) side chains including keratan sulphate (KS), human natural killer trisaccharide (HNK-1) and chondroitin sulphate (CS). These convey unique tissue-specific functional properties in water imbibition, space-filling, matrix stabilisation or embryonic cellular regulation. Aggrecan also interacts with morphogens and growth factors directing tissue morphogenesis, remodelling and metaplasia. HNK-1 aggrecan glycoforms direct neural crest cell migration in embryonic development and is neuroprotective in perineuronal nets in the brain. The ability of the aggrecan core protein to assemble CS and KS chains at high density equips cartilage aggrecan with its well-known water-imbibing and weight-bearing properties. The importance of specific arrangements of GAG chains on aggrecan in all its forms is also a primary morphogenetic functional determinant providing aggrecan with unique tissue context dependent regulatory properties. The versatility displayed by aggrecan in biodiverse contexts is a function of its GAG side chains.

Structural characterization and proliferation activity of chondroitin sulfate from the sturgeon, Acipenser schrenckii

The cartilages of marine fish, such as sharks and sturgeon, are important resources of the bioactive chondroitin sulfate (CS). To explore glycosaminoglycans from marine fish, polysaccharides from the cartilage of the sturgeon, Acipenser schrenckii, were extracted. Using enzyme-assisted extraction and anion-exchange chromatography, an uronic acid-containing polysaccharide, YG-1, was isolated. YG-1 is composed of GlcN, GlcUA, GalN, and Gal, in the ratio of 1.4: 3.4: 3.7: 1.0, and its molecular weight was determined to be 3.0 × 10⁵ Da. YG-1 was confirmed to be chondroitin 4-sulfate (CS) composed of →4GlcAβ1→3GalNAc4Sβ1→ and minor →4GlcAβ1→3GalNAcβ1→, which was confirmed using IR spectroscopy, disaccharide composition analysis, and NMR. Bioactivity studies, including MTT assay and scratch-wound assays revealed that CS from Acipenser schrenckii had significant proliferation activity. The proliferation activity of the polysaccharide, YG-1, was related to Fibroblast growth factor 2 (FGF2). GalNAc 4S of YG-1 could be the binding sites of FGF2 and FGFR.

Extraction and characterization of an alginate from the Iranian brown seaweed Nizimuddinia zanardini

Sodium alginate from Nizimuddinia zanardini (an Iranian brown algae) was extracted with acid and alkaline solutions, partially and totally hydrolyzed and analyzed for its biochemical composition. 1H NMR spectroscopy, SEC-MALLS, HPAEC and FT-IR were performed to determine its structure and its physico-chemical properties. This alginate has a M/G ratio of 1.1, a molecular weight of 103 kDa, a polydispersity index of 1.22, and an intrinsic viscosity of 342 mL/g. Its antioxidant activity was tested by DPPH radical scavenging showing its potential for food preservation. Rheological properties of solutions of this alginate with concentrations between 1 and 5% (w/v) in water and 0.5 M NaCl were investigated indicating a Newtonian fluid type behaviour in water and a shear thinning fluid type behaviour in NaCl solutions.

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.

Spondyloepiphyseal dysplasia, Omani type: further definition of the phenotype

Spondyloepiphyseal dysplasia (SED), Omani type (OMIM 608637) is a recessively inherited skeletal dysplasia previously described in two distantly related families from the Republic of Oman. The phenotype consists of short stature, severe kyphoscoliosis, arthritic joints (elbows, wrists, knees), secondary large joint dislocations, rhizomelia, fusion of carpal bones and mild brachydactyly. Affected individuals were homozygous for a missense mutation, R304Q in CHST3 that encodes the enzyme chondroitin 6-O-sulfotransferase-1 (C6ST-1). This enzyme mediates the sulfation of proteoglycans, particularly chondroitin sulfate (CS), in the extracellular matrix of cartilage. Here we describe the identification of a mutation (857T > C predicting the substitution L286P) in CHST3 in a Turkish family and extend the clinical phenotype of SED-Omani type to include congenital joint dislocation, club feet, ventricular septal defect, deafness, metacarpal shortening and accessory carpal ossification centers. Fibroblasts and urine obtained from affected patients demonstrated negligible levels of 6-O-sulfated GalNAc residue in CS. Furthermore, the 6-O-sulfotransferase activity of cloned C6ST-1 into which the L286P mutation had been introduced was dramatically reduced, confirming the pathogenicity of this substitution. These results indicate that the clinical consequences of a deficiency of 6-O-sulfation in CS can be varied and that a clinical spectrum may exist similar to that seen in other skeletal dysplasias characterized by disorders of proteoglycan sulfation.

Capillary electrophoresis of complex natural polysaccharides

Complex natural polysaccharides, glycosaminoglycans (GAGs), are a class of ubiquitous macromolecules that exhibit a wide range of biological functions and participate and regulate multiple cellular events and (patho)physiological processes. They are generally present either as free chains (hyaluronic acid and bacterial acidic polysaccharides) or as side chains of proteoglycans (PGs; chondroitin/dermatan sulfate, heparin/heparan sulfate, and keratan sulfate) and are most often found in cell membranes and in the extracellular matrix. The recent emergence of modern analytical tools for their study has produced a virtual explosion in the field of glycomics. CE, due to its high resolving power and sensitivity, has been useful in the analysis of intact GAGs and GAG-derived oligosaccharides and disaccharides affording concentration and structural characterization data essential for understanding the biological functions of GAGs. In this review, novel off-line and on-line CE-MS and MS/MS methods for screening of GAG-derived oligosaccharides and disaccharides will be discussed.

Identification of a novel chondroitin hydrolase in Caenorhabditis elegans

Hyaluronidases have been postulated to be the enzyme acting at the initial step of chondroitin sulfate (CS) catabolism in vivo. Since chondroitin (Chn) but not hyaluronic acid (HA) has been detected in Caenorhabditis elegans, the nematode is a good model for elucidating the mechanism of the degradation of CS/Chn in vivo. Here we cloned the homolog of human hyaluronidase in C. elegans, T22C8.2. The Chn-degrading activity in vitro was first demonstrated when it was expressed in COS-7 cells. The enzyme cleaved preferentially Chn. CS-A and CS-C were also depolymerized but to lesser extents, and HA was hardly degraded. In order of preference, the substrates ranked Chn >> CS-A > CS-C >> HA. The products of the degradation of Chn by the enzyme were characterized by anion-exchange high performance liquid chromatography and delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The structure of the major component in the digest was determined as GlcUAbeta1-3GalNAcbeta1-4GlcUAbeta1-3GalNAc, where GlcUA and GalNAc represent D-glucuronic acid and N-acetyl-D-galactosamine, respectively, indicating that this enzyme is a Chn hydrolase, an endo-beta-galactosaminidase specific for Chn. Investigation of the effects of pH on the activity revealed the optimum pH of Chn hydrolase to be 6.0. Since Chn in C. elegans has been demonstrated to play critical roles in cell division, Chn hydrolase possibly regulates the function of Chn in vivo. This is the first demonstration of a Chn hydrolase in an animal.