A novel fibrinolytic enzymes from the Korean traditional fermented food-Jotgal: Purification and characterization

Diverse origins of fibrinolytic enzymes: A comprehensive review

Fibrinolytic enzymes cleave fibrin which plays a crucial role in thrombus formation which otherwise leads to cardiovascular diseases. While different fibrinolytic enzymes have been purified, only a few have been utilized as clinical and therapeutic agents; hence, the search continues for a fibrinolytic enzyme with high specificity, fewer side effects, and one that can be mass-produced at a lower cost with a higher yield. In this context, this review discusses the physiological mechanism of thrombus formation and fibrinolysis, and current thrombolytic drugs in use. Additionally, an overview of the optimization, production, and purification of fibrinolytic enzymes and the role of Artificial Intelligence (AI) in optimization and the patents granted is provided. This review classifies microbial as well as non-microbial fibrinolytic enzymes isolated from food sources, including fermented foods and non-food sources, highlighting their advantages and disadvantages. Despite holding immense potential for the discovery of novel fibrinolytic enzymes, only a few fermented food sources limited to Asian countries have been studied, necessitating the research on fibrinolytic enzymes from fermented foods of other regions. This review will aid researchers in selecting optimal sources for screening fibrinolytic enzymes and is the first one to provide insights and draw a link between the implication of source selection and in vivo application.

Research progress on the fibrinolytic enzymes produced from traditional fermented foods

Cardiovascular diseases (CVDs) are a global health problem and leading cause of death worldwide. Thrombus formation, one of the CVDs, is essentially the formation of fibrin clots. The existing thrombolytic agents have the disadvantages of high price, short half-life, and high bleeding risk; hence, there is an urgent need to find the alternative thrombolytic agents. In recent years, traditional fermented foods have been widely investigated for their outstanding effects in the prevention and treatment of thrombus formation. In this review, we have focused on fibrinolytic enzymes produced by microorganisms during the fermentation of traditional fermented foods and their potential use for treating CVDs. First, we discussed about the sources of fibrinolytic enzymes and microbial strains that produce those enzymes followed by the optimization of fermentation process, purification, and physicochemical properties of fibrinolytic enzymes. Finally, we have summarized the thrombolytic effects of fibrinolytic enzymes in humans and mice. Fibrinolytic enzymes produced by microorganisms during the fermentation of traditional fermented foods not only lyse thrombi but also acts as anti-atherosclerotic, anti-hyperlipidemia, and neuroprotection agents. Therefore, fibrinolytic enzymes from traditional fermented foods have great potential for the prevention and treatment of CVDs.

Purification, biochemical characterization and fibrinolytic potential of proteases produced by bacteria of the genus Bacillus: a systematic literature review

Thrombosis is a hematological disorder characterized by the formation of intravascular thrombi, which contributes to the development of cardiovascular diseases. Fibrinolytic enzymes are proteases that promote the hydrolysis of fibrin, promoting the dissolution of thrombi, contributing to the maintenance of adequate blood flow. The characterization of new effective, safe and low-cost fibrinolytic agents is an important strategy for the prevention and treatment of thrombosis. However, the development of new fibrinolytics requires the use of complex methodologies for purification, physicochemical characterization and evaluation of the action potential and toxicity of these enzymes. In this context, microbial enzymes produced by bacteria of the Bacillus genus are promising and widely researched sources to produce new fibrinolytics, with high thrombolytic potential and reduced toxicity. Thus, this review aims to provide a current and comprehensive understanding of the different Bacillus species used for the production of fibrinolytic proteases, highlighting the purification techniques, biochemical characteristics, enzymatic activity and toxicological evaluations used.

Development of the Antithrombotic Peptide LEKNSTY Targeting the Collagen Surface: I. Design and Validation

Exposed collagen on the diseased vessel wall is crucial for arterial thrombosis. The currently developed antithrombotic drugs mostly target blood components such as platelets and suffer from the risk of bleeding. Therefore, anticollagen therapy of covering the collagen surface was proposed as an alternative in our previous study, and an antithrombotic peptide LWWNSYY was designed and validated. However, its application was hindered due to the poor water solubility. In the present study, in order to develop a novel antithrombotic peptide with enhanced water solubility, redesigning of LWWNSYY to LEKNSTY using the EK pattern was proposed. Improved solubility was obtained for LEKNSTY. Moreover, the binding of LEKNSTY on the collagen surface was confirmed by molecular docking, molecular dynamics simulations, and experimental validation. A K_d of 0.91 ± 0.44 μM was observed. The effective inhibition of platelet adhesion on the collagen surface by LEKNSTY was demonstrated at an IC₅₀ of 2.48 ± 0.59 μg/mL. Therefore, the successful design of the antithrombotic peptide LEKNSTY was confirmed, which would facilitate the research into the interface involving thrombus and the development of antithrombotic agents.

Development of the Antithrombotic Peptide LEKNSTY Targeting the Collagen Surface: II. Improvement of Plasma Stability

The development of antithrombotic peptides targeting collagen was proven effective, and an effective antithrombotic peptide LEKNSTY was obtained in part I. However, the plasma stability of LEKNSTY was found to be not good enough. In this part, the LEKNSTY was further optimized for improvement in plasma stability by substitution using d-amino acid residues. Two novel antithrombotic peptides LekNStY and lEKnsTy were designed, where lowercase letters represent d-amino acid residues. Improvements in plasma stability of both LekNStY and lEKnsTy were experimentally confirmed. Moreover, good binding of these antithrombotic peptides on the collagen surface was confirmed by molecular dynamics simulation and experimental validation. For example, a K_d of only 0.75 ± 0.10 μM was observed for lEKnsTy. Moreover, LekNStY and lEKnsTy were found to inhibit platelet adhesion on the collagen surface more effectively than LEKNSTY, and the IC₅₀ of lEKnsTy was only 2/5 of that of LEKNSTY. These results confirmed the successful design of LekNStY and lEKnsTy that had good plasma stability and could effectively inhibit arterial thrombosis, which would be helpful for the research into interfaces involved in thrombus formation and the development of antithrombotic nanomedicine.

Switchable deep eutectic solvent driven micellar extractive fermentation of ultrapure fibrin digesting enzyme from Bacillus subtilis

Fibrinolytic protease (FLP) is a therapeutic enzyme used in the treatment of thrombolytic diseases. The present study proposed the concept of pH-driven swappable micellar two-phase extraction for the concurrent production and purification of FLP from Bacillus subtilis at cloud point extraction. Extractive fermentation was carried out with a pH swap mechanism and FLP was extracted to the top phase by surfactant deep eutectic solvents (SDES). Shrimp waste was chosen as a sustainable low-cost substrate that yielded a maximum protease of 185 U/mg. Six SDESs were synthesized with nonionic surfactants as hydrogen bond donors and quaternary ammonium salts as hydrogen bond acceptors and their association was confirmed by H¹ NMR. Thermophysical investigation of the synthetic SDES was accomplished as a function of temperature. Response surface methodology for extractive fermentation was performed with the concentration of SADES (35% w/v), Na₂SO₄ (15% w/v) and pH (6.3) as variables and the enzyme activity (248 IU/mg) as a response. Furthermore, purification using gel filtration chromatography was used to quantify the amount of enzyme obtained in the extraction phase (849 IU/ml). After final purification with an anion exchange column, the maximum purity fold (22.32) with enzyme activity (1172 IU/ml) was achieved. The in-vitro fibrinolytic activity has been confirmed using a fibrin plate assay.

Microbial Fibrinolytic Enzymes as Anti-Thrombotics: Production, Characterisation and Prodigious Biopharmaceutical Applications

Cardiac disorders such as acute myocardial infarction, embolism and stroke are primarily attributed to excessive fibrin accumulation in the blood vessels, usually consequential in thrombosis. Numerous methodologies including the use of anti-coagulants, anti-platelet drugs, surgical operations and fibrinolytic enzymes are employed for the dissolution of fibrin clots and hence ameliorate thrombosis. Microbial fibrinolytic enzymes have attracted much more attention in the management of cardiovascular disorders than typical anti-thrombotic strategies because of the undesirable after-effects and high expense of the latter. Fibrinolytic enzymes such as plasminogen activators and plasmin-like proteins hydrolyse thrombi with high efficacy with no significant after-effects and can be cost effectively produced on a large scale with a short generation time. However, the hunt for novel fibrinolytic enzymes necessitates complex purification stages, physiochemical and structural-functional attributes, which provide an insight into their mechanism of action. Besides, strain improvement and molecular technologies such as cloning, overexpression and the construction of genetically modified strains for the enhanced production of fibrinolytic enzymes significantly improve their thrombolytic potential. In addition, the unconventional applicability of some fibrinolytic enzymes paves their way for protein hydrolysis in addition to fibrin/thrombi, blood pressure regulation, anti-microbials, detergent additives for blood stain removal, preventing dental caries, anti-inflammatory and mucolytic expectorant agents. Therefore, this review article encompasses the production, biochemical/structure-function properties, thrombolytic potential and other surplus applications of microbial fibrinolytic enzymes.

Role of Fibrinolytic Enzymes in Anti-Thrombosis Therapy

Thrombosis, a major cause of deaths in this modern era responsible for 31% of all global deaths reported by WHO in 2017, is due to the aggregation of fibrin in blood vessels which leads to myocardial infarction or other cardiovascular diseases (CVDs). Classical agents such as anti-platelet, anti-coagulant drugs or other enzymes used for thrombosis treatment at present could leads to unwanted side effects including bleeding complication, hemorrhage and allergy. Furthermore, their high cost is a burden for patients, especially for those from low and middle-income countries. Hence, there is an urgent need to develop novel and low-cost drugs for thrombosis treatment. Fibrinolytic enzymes, including plasmin like proteins such as proteases, nattokinase, and lumbrokinase, as well as plasminogen activators such as urokinase plasminogen activator, and tissue-type plasminogen activator, could eliminate thrombi with high efficacy rate and do not have significant drawbacks by directly degrading the fibrin. Furthermore, they could be produced with high-yield and in a cost-effective manner from microorganisms as well as other sources. Hence, they have been considered as potential compounds for thrombosis therapy. Herein, we will discuss about natural mechanism of fibrinolysis and thrombus formation, the production of fibrinolytic enzymes from different sources and their application as drugs for thrombosis therapy.

Purification, characterization, and chemical modification of Bacillus velezensis SN-14 fibrinolytic enzyme

Fermented bean foods are a crucial source of fibrinolytic enzymes. The presented study aimed to purify, characterize, and chemically modify Bacillus velezensis SN-14 fibrinolytic enzyme. The fibrinolytic enzyme was purified using CTAB/isooctane/hexyl alcohol/n-butyl alcohol reverse micellar system, and the purified enzyme was chemically modified to improve its enzymatic activity and stability. Enzyme activity recovery and the purification fold for this enzyme were 44.5 ± 1.9% and 4.93 ± 0.05 fold, respectively. SDS-PAGE results showed that the molecular weight of the purified fibrinolytic enzyme was around 28 kDa. Besides, the optimum temperature and pH of the purified fibrinolytic enzyme were 37 °C and 8-9, respectively. Fe²⁺, mPEG5000, and pepsin were used for chemical modification and for improving the activity and stability of the purified enzyme. Thermal and acid-base stability of chemically modified enzymes increased significantly, whereas enzymatic activity increased by 7.3 times. After 30 d of frozen storage, the modified enzyme's activity was remarkably lower (33.2%) than the unmodified enzyme (60.6%). The current study on B. velezensis SN-14 fibrinolytic enzyme and chemical modification method using Fe²⁺, mPEG5000, and pepsin provide a reference for developing fibrinolytic drugs and foods.

Purification, physicochemical properties, and statistical optimization of fibrinolytic enzymes especially from fermented foods: A comprehensive review

Fibrinolytic enzymes are proteases responsible for cleavage of fibrin mesh in thrombus clots, which are the primary causative agents in cardiovascular diseases. Developing safe, effective and cheap thrombolytic agents are important for prevention and cure of thrombosis. Although a wide variety of sources have been discovered for fibrinolytic enzymes, only few of them have been employed in clinical and therapeutic applications due to the drawbacks such as high cost of production, low stability of enzyme or therapeutic side effects. However, the discovery of new fibrinolytic enzymes requires complex purification stages and characterization, which gives an insight into their diverse modes of action. Post-discovery, approaches such as a) statistical optimization for fermentative bioprocessing and b) genetic engineering are advantageous in providing economic viability by finding simple and cost-effective medium, strain development with sufficient nutrient supplements for stable and high-level production of recombinant enzyme. This review provides a comprehensive understanding of different sources, purification techniques, production through genetic engineering approaches and statistical optimization of fermentation parameters as proteases have a wide variety of industrial and biotechnological applications making 60% of total enzyme market worldwide. New strategies targeting increased enzyme yields, non-denaturing environments, improved stability, enzyme activity and strain improvement have been discussed.