Identification, purification and characterization of a novel collagenolytic serine protease from fig (Ficus carica var. Brown Turkey) latex

Valorization of agro-industrial residues using Aspergillus heteromorphus URM0269 for protease production: Characterization and purification

This study aimed to produce, characterize and purify a protease from Aspergillus heteromorphus URM0269. After production by solid fermentation of wheat bran performed according to a central composite design, protease was characterized in terms of biochemical, kinetic, and thermodynamic parameters for further purification by chromatography. Proteolytic activity achieved a maximum value of 57.43 U/mL using 7.8 g of wheat bran with 40 % moisture. Protease displayed high stability in the pH and temperature ranges of 5.0-10.0 and 20-30 °C, respectively, and acted optimally at pH 7.0 and 50 °C. The enzyme, characterized as a serine protease, followed Michaelis-Menten kinetics with a maximum reaction rate of 140.0 U/mL and Michaelis constant of 11.6 mg/mL. Thermodynamic activation parameters, namely activation Gibbs free energy (69.79 kJ/mol), enthalpy (5.86 kJ/mol), and entropy (-214.39 J/mol.K) of the hydrolysis reaction, corroborated with kinetic modeling showing high affinity for azocasein. However, thermodynamic parameters suggested a reversible mechanism of unfolding. Purification by chromatography yielded a protease purification factor of 7.2, and SDS-PAGE revealed one protein band with a molecular mass of 14.7 kDa. Circular dichroism demonstrated a secondary structure made up of 45.6 % α-helices. These results show the great potential of this protease for future use in the industrial area.

Proteolytic Activity of Silkworm Thorn (Cudrania tricuspidata) Fruit for Enzymatic Hydrolysis of Food Proteins

This study aimed to isolate the proteolytic fraction from the silkworm thorn fruit (Cudrania tricuspidata) through ethanol precipitation at different ratios, and to determine its proteolytic activity and optimal activity conditions. Furthermore, the hydrolysis characteristics and antioxidant activity of soy protein isolate (SPI) and whey protein concentrate (WPC) hydrolyzates obtained through the enzymatic hydrolysis of freeze-dried silkworm thorn fruit powder (SF) were evaluated. For isolation and partial purification of proteolytic fraction, the water-solubilized fraction of the silkworm thorn fruit was purified through ethanol precipitation at four different ratios of 1:1, 1:2, 1:4, and 1:6 (v/v). The protein recovery rate, caseinolytic activity, protein pattern, and optimal activity (pH, temperature, and inhibitors) of fractional ethanol precipitate obtained from the silkworm thorn fruit (ESF) were evaluated. The proteolytic fraction obtained from silkworm thorn fruit exhibited a major protein band around 65-70 kDa and showed the highest proteolytic activity at a 1:4 ratio of ethanol precipitation (p < 0.05). The optimal activity of the measured enzyme fraction was determined to be at pH 9.0 and 50 °C, and the proteolytic activity of ESF was almost inhibited by phenyl methyl sulphonyl fluoride (PMSF, 2 mM), a serine protease inhibitor. Compared to Alcalase and papain, extensively used as commercial enzymes, the silkworm thorn fruit powder was less effective in hydrolyzing SPI and WPC. Nevertheless, SPI and WPC hydrolyzates mediated with silkworm thorn fruit powder showed even better antioxidant activities than those mediated with Alcalase and papain. Thus, our results show the potential application of silkworm thorn fruit as a novel source of plant protease for producing human-grade protein hydrolyzates.

Extracellular collagenase isolated from Streptomyces antibioticus UFPEDA 3421: purification and biochemical characterization

Collagenases are proteases able to degrade native and denatured collagen, with broad applications such as leather, food, and pharmaceutical industries. The aim of this research was to purify and characterize a collagenase from Streptomyces antibioticus. In the present work, the coffee ground substrate provided conditions to obtaining high collagenase activity (377.5 U/mL) using anion-exchange DEAE-Sephadex G50 chromatographic protocol. SDS-PAGE revealed the metallo-collagenase with a single band of 41.28 kDa and was able to hydrolyzed type I and type V collagen producing bioactive peptides that delayed the coagulation time. The enzyme activity showed stability across a range of pH (6.0-11) and temperature (30-55 °C) with optima at pH 7.0 and 60 °C, respectively. Activators include Mg+2, Ca+2, Na+, K+, while full inhibition was given by other tested metalloproteinase inhibitors. Kinetic parameters (Km of 27.14 mg/mol, Vmax of 714.29 mg/mol/min, Kcat of 79.9 s-1 and Kcat/Km of 2.95 mL/mg/s) and thermodynamic parameters (Ea of 65.224 kJ/mol, ΔH of 62.75 kJ/mol, ΔS of 1.96 J/mol, ΔG of 62.16 kJ/mol, ΔGE-S of 8.18 kJ/mol and ΔGE-T of -2.64 kJ/mol) were also defined. Coffee grounds showed to be an interesting source to obtaining a collagenase able to produce bioactive peptides with anticoagulant activity.

Thermostable ficin from jelly fig (Ficus pumila var. awkeotsang) latex: purification, identification and characterization

BACKGROUND

The achenes/seeds of endemic jelly fig (Ficus pumila var. awkeotsang) fruit have been applied to prepare a traditional beverage in Taiwan. Upon fruit harvest, jelly fig latex exuded from stalks was discarded. Protease activity was monitored in its latex. Proteases capable of hydrolyzing proteins have many application aspects based on diverse characteristics. Commercial plant proteases are frequently from latex.

RESULTS

The latex protease of jelly fig, termed FaFicin, was purified to homogeneity with a molecular mass of ~32 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. According to liquid chromatographic-tandem mass spectrometric analyses, the expected protein band of protease was matched to ficin A, ficin B or chymopapain from common fig or papaya. Iodoacetamide, an inhibitor of cysteine protease, inhibited its protease activity completely. Hence FaFicin was identified as a papain-like cysteine protease (PLCP), exhibiting more than 80% and 70% activity as assayed at pH 5-8 and 40-70 °C, respectively. It maintained ~89% of initial activity after 120 min at 55 °C and pH 7. Moreover, FaFicin could degrade the myosin and actin of meat, and clot milk.

CONCLUSION

The ficin FaFicin was obtained, purified and identified as a PLCP member from agricultural waste: jelly fig latex. It possessed activity under a wide range of pH values and temperature, and exhibited excellent thermostability. Based on its initial evaluation as a meat tenderizer and milk clotting reagent, the application of FaFicin was possible, which may extend utilization of jelly fig. © 2022 Society of Chemical Industry.

Production of Plant Proteases and New Biotechnological Applications: An Updated Review

An updated review of emerging plant proteases with potential biotechnological application is presented. Plant proteases show comparable or even greater performance than animal or microbial proteases for by‐product valorization through hydrolysis for, for example, cheese whey, bird feathers, collagen, keratinous materials, gelatin, fish protein, and soy protein. Active biopeptides can be obtained as high added value products, which have shown numerous beneficial effects on human health. Plant proteases can also be used for wastewater treatment. The production of new plant proteases is encouraged for the following advantages: low cost of isolation using simple procedures, remarkable stability over a wide range of operating conditions (temperature, pH, salinity, and organic solvents), substantial affinity to a broad variety of substrates, and possibility of immobilization. Vegetable proteases have enormous application potential for the valorization of industrial waste and its conversion into products with high added value through low‐cost processes.

Insight into the collagen-degrading activity of a serine protease in the latex of Ficus carica cultivar Masui Dauphine

Ficus carica produces, in addition to the cysteine protease ficin, a serine protease. Earlier study on a serine protease from F. carica cultivar Brown Turkey showed that it specifically degraded collagen. In this study, we characterized the collagenolytic activity of a serine protease in the latex of F. carica cultivar Masui Dauphine. The serine protease degraded denatured, but not undenatured, acid-solubilized type I collagen. It also degraded bovine serum albumin, while the collagenase from Clostridium histolyticum did not. These results indicated that the serine protease in Masui Dauphine is not collagen-specific. The protease was purified to homogeneity by two-dimensional gel electrophoresis, and its partial amino acid sequence was determined by liquid chromatography-tandem mass spectrometry. BLAST searches against the Viridiplantae (green plants) genome database revealed that the serine protease was a subtilisin-like protease. Our results contrast with the results of the earlier study stating that the serine protease from F. carica is collagen-specific.

Papain-Like Cysteine Protease Gene Family in Fig (Ficus carica L.): Genome-Wide Analysis and Expression Patterns

The papain-like cysteine proteases (PLCPs) are the most abundant family of cysteine proteases in plants, with essential roles in biotic/abiotic stress responses, growth and senescence. Papain, bromelain and ficin are widely used in food, medicine and other industries. In this study, 31 PLCP genes (FcPCLPs) were identified in the fig (Ficus carica L.) genome by HMM search and manual screening, and assigned to one of nine subfamilies based on gene structure and conserved motifs. SAG12 and RD21 were the largest subfamilies with 10 and 7 members, respectively. The FcPCLPs ranged from 1,128 to 5,075 bp in length, containing 1-10 introns, and the coding sequence ranged from 624 to 1,518 bp, encoding 207-505 amino acids. Subcellular localization analysis indicated that 24, 2, and 5 PLCP proteins were targeted to the lysosome/vacuole, cytoplasm and extracellular matrix, respectively. Promoter (2,000 bp upstream) analysis of FcPLCPs revealed a high number of plant hormone and low temperature response elements. RNA-seq revealed differential expression of 17 FcPLCPs in the inflorescence and receptacle, and RD21 subfamily members were the major PLCPs expressed in the fruit; 16 and 5 FcPLCPs responded significantly to ethylene and light, respectively. Proteome analyses revealed 18 and 5 PLCPs in the fruit cell soluble proteome and fruit latex, respectively. Ficins were the major PLCP in fig fruit, with decreased abundance in inflorescences, but increased abundance in receptacles of commercial-ripe fruit. FcRD21B/C and FcALP1 were aligned as the genes encoding the main ficin isoforms. Our study provides valuable multi-omics information on the FcPLCP family and lays the foundation for further functional studies.

Broad range of substrate specificities in papain and fig latex enzymes preparations improve enumeration of Listeria monocytogenes

Numerous applications of proteolytic enzymes include dissociation of fermented meat products for the enumeration of `foodborne pathogenic bacteria. The use of trypsin for this cause is abandoned due to the high concentration of the enzyme affecting released bacteria. Papain, as a suggested replacement, and fig latex preparation with high extent of papain-like enzymes have the potential to be applied for bacteria enumeration. Both enzymatic preparations, originating from papaya and fig, showed a broader range of substrate specificities including gelatinolytic activity, especially prominent in the case of ficin and attributed to both, cysteine protease ficin and serine protease by the analysis of 2D zymography with specific inhibitors. The activity towards native collagen, mild in the case of papain, and extensive in the case of fig latex was proved by structural analysis of digested collagen by infrared spectroscopy. Further exploration of their potential for dissociation of fermented meat products showed that both papain and fig latex enzymes are stable in the presence of detergents Tween 20 and Triton X-100 and effective in the enumeration of Listeria monocytogenes. Gelatenolytic activity, and at least partial collagenolytic activity and stability in procedure conditions make papaya and fig latex proteases potent for this application in significantly lower concentrations than previously used enzymes. As a mixture of proteolytic enzymes with divergent characteristics, fig latex preparation shows higher efficiency in Listeria monocytogenes release than papain, conserved even in the presence of stronger non-ionic detergent Triton X-100.

Trypsin activity and freeze-thaw stability in the presence of ions and non-ionic surfactants

Trypsin is a serine protease with important applications such as protein sequencing and tissue dissociation. Preserving protein structure and its activity during freeze-thawing and prolonging its shelf life is one of the most interesting tasks in biochemistry. In the present study, trypsin cryoprotection was achieved by altering buffer composition. Sodium phosphate buffer at pH 8.0 led to pH shift-induced destabilization of trypsin and formation of a molten globule, followed by significant activity loss (about 70%). Potassium phosphate and ammonium bicarbonate buffers at pH 8.0 were used with up to 90% activity recovery rate after 7 freeze-thaw cycles. The addition of non-ionic surfactants Tween 20 and Tween 80 led to up to 99% activity recovery rate. Amide I region changes, corresponding to specific secondary structures in the Fourier transform infrared (FTIR) spectrum, were modest in the case of Tween 20 and Tween 80. On the other hand, the addition of Triton X-100 led to the destabilization of α-helicoidal segments of trypsin structure after 7 freeze-thaw cycles but also increased protein substrate availability.

The first report on molecular cloning, functional expression, purification, and statistical optimization of Escherichia coli-derived recombinant Ficin from Iranian fig tree (Ficus carica cv.Sabz)

The enzyme ficin, abundantly found in the leaves of the common Fig (Ficus carica. L), is a cysteine protease of the plant endopeptidase family. In terms of activity, this enzyme mimics the activity of the papain enzyme. However, the enzyme is more acidic than papain and binds with higher efficiency to its substrate. Ficin is widely used in the food and pharmaceutical industry along with the medical diagnosis. To date, there are no available data on cloning and recombinant production of various isoforms of ficin. In the present study, after the cloning process and optimized expression of ficin in E. coli BL21, by means of the central composite design (CCD) and approach-based response surface methodology (RSM), the recombinant protein was purified using the Ni-sepharose column and gel filtration. The activity of ficin was determined by its ability to hydrolyze the bovine casein enzyme as a substrate. These results showed the presence of different isoforms of ficin in this cultivar that they are distinct in terms of DNA coding sequences. The optimum conditions for maximum production of the recombinant ficin enzyme in E. coli were as follows; a cell density of 1.25, post-induction time 7 h, 10% (w/v) lactose concentration, and shaking at 115 rpm at 24 °C. The concentration of purified product was reported to be 0.27 mg/ml. The optimization procedures increased the amounts of ficin production by approximately 3 folds (0.67 mg/ml) compared with the expiration level (in the absence of optimization). Also, our findings showed that the recombinant ficin was able to hydrolyze casein, denoting the functionality of the enzyme when used in-vitro. The pitfall of cutting-off the young branches of the common fig tree to purify the enzyme from the young shoots was successfully solved in this study.

The roles of histidine and tyrosine residues in the active site of collagenase in Grimontia hollisae

Collagenase from the Grimontia hollisae strain 1706B (Ghcol) is a zinc metalloproteinase with the zinc-binding motif H492EXXH496. It exhibits higher collagen-degrading activity than the collagenase from Clostridium histolyticum, which is widely used in industry. We previously examined the pH and temperature dependencies of Ghcol activity; Glu493 was thought to contribute acidic pKa (pKe1), while no residue was assigned to contribute alkaline pKa (pKe2). In this study, we introduced nine single mutations at the His or Tyr residues in and near the active site. Our results showed that H412A, H485A, Y497A, H578A and H737A retained the activities to hydrolyze collagen and gelatin, while H426A, H492A, H496A and Y568A lacked them. Purification of active variants H412A, H485A, H578A and H737A, along with inactive variants H492A and H496A, were successful. H412A preferred (7-methoxycoumarin-4-yl)acetyl-L-Lys-L-Pro-L-Leu-Gly-L-Leu-[N3-(2,4-dinitrophenyl)-L-2,3-diaminopropionyl]-L-Ala-L-Arg-NH2 to collagen, while H485A preferred collagen to the peptide, suggesting that His412 and His485 are important for substrate specificity. Purification of the active variant Y497A and inactive variants H426A and Y568A were unsuccessful, suggesting that these three residues were important for stability. Based on the reported crystal structure of clostridial collagenase, Tyr568 of Ghcol is suggested to be involved in catalysis and may be the ionizable residue for pKe2.

A contradictory action of procoagulant ficin by a fibrinolytic serine protease from Egyptian Ficus carica latex

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We purified a serine protease from Ficus carica latex.

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Serine protease had a high tendency to hydrolyze fibrinogin.

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Serine protease inhibited blood coagulation.

Ficus carica is one of the most popular and edible plants. Its trees emanate latex of high medical importance. The well-studied procoagulant effect of ficin is a hallmark of this latex which protrudes an interesting question of how can the plant control this effect? In the present work, we purified and characterized a serine protease (FPIII) with fibrinolytic activity from F. carica latex and study the anticoagulant character of the latex. FPIII was inhibited by PMSF and its molecular weight was 48 kDa. The optimum pH and temperature of FPIII were detected at 8.5 and 60 °C, respectively. The activation energy of FPIII was 7 kcal/mol and was thermal stable up to 60 °C. FPIII tended to hydrolyze different protein substrates and showed a good catalytic efficiency (K_cat/K_m). The anticoagulant effects and fibrinogenolytic activities of latex crude extract and FPIII were detected, which controls the procoagulant effect of ficin.

Identification of a novel alkaline serine protease from gazami crab (Portunus trituberculatus) hepatopancreas and its hydrolysis of myofibrillar protein

Serine proteases are thought to play a key role in the muscle softening of gazami crab (Portunus trituberculatus) during storage. A serine protease, Pt-sp2, was purified from the hepatopancreas of gazami crab using ammonium sulfate precipitation, anion-exchange and gel filtration chromatography, and was analyzed by mass spectrometry, transcriptome and bioinformatics. It revealed that Pt-sp2 was trypsin-like, with no 100% identical proteins in the NCBI database. The molecular weight of Pt-sp2 was approximately 37.2 kDa. Its optimum pH and temperature were 9.0 and 50 °C, respectively, using t-Butyloxy‑carbonyl-Phe-Ser-Arg-4-methyl-coumaryl-7-amide as a substrate. Pt-sp2 was activated in the presence of Ca²⁺. Both soybean trypsin inhibitor and Nα-Tosyl-l-lysine chloromethyl ketone hydrochloride completely suppressed Pt-sp2 activity, while it was only partially inhibited by phenylmethylsulfonyl fluoride and EDTA. However, PMSF, Pepstatin A and cystatin inhibitor E-64 showed no inhibition on Pt-sp2 protease activity. The Km value of Pt-sp2 was 0.82 μM, and Pt-sp2 effectively hydrolyzed myofibrillar protein at 37 °C.

Characterization of proteases activities in Ficus carica cultivars

In this study, we characterized protease activities of 23 Ficus carica cultivars. Extracts of fruit, branch, and leaf of Masui Dauphine, one of the most representative F. carica cultivars in Japan, exhibited gelatin-hydrolyzing activity, both in the absence and presence of a cysteine protease-specific inhibitor, E-64, suggesting that not only ficin (classified as cysteine protease) but also collagenase (classified as serine protease) were involved in the digestion of gelatin. In the hydrolysis of (7-methoxycoumarin-4-yl)acetyl-l-Lys-l-Pro-l-Leu-Gly-l-Leu-[N³ -(2,4-dinitrophenyl)-l-2,3-diaminopropionyl]-l-Ala-l-Arg-NH₂ , all branch extracts of 23 F. carica cultivars exhibited the activity both in the absence and presence of cysteine protease-specific inhibitor E-64, indicating that they contain ficin and collagenase. During digestion of acid-solubilized type I collagen by the branch extract of Masui Dauphine at 40-55 °C, collagen was completely digested in the absence of E-64, while it was partially digested in the presence of the inhibitor, indicating that the manner of digestion differed between ficin and collagenase contained in the extract. These results suggest that F. carica is attractive for industrial use to digest collagen. PRACTICAL APPLICATION: The industrial use of F. carica might be enhanced by efficiently utilizing these proteases and/or selecting the appropriate F. carica cultivar. Collagen is one of the targets to which our results might be applied. It is widely accepted today that collagen and its digestion products could be useful as functional food. F. carica is a potential candidate for use in not only complete but also partial digestion of collagen.

Isolation, identification, and stability of Ficin 1c isoform from fig latex

Purified alkaline ficin isoform, identified as Ficin 1c regarding fig transcriptome, shows decreased stability compared to the ficin isoform mixture.

Laticifers, Latex, and Their Role in Plant Defense

Latex, a sap produced by cells called laticifers, occurs in plants of wide taxonomic diversity. Plants exude latex sap in response to physical damage. Questions about the function of latex or the underlying mechanisms persist, but a role in defense is likely. The presence of constitutive peptidases in latex sap in addition to inducible and de novo synthesized pathogenesis-related proteins (PR-proteins), raises the question about the role that each sap component plays to protect plants and how synergism occurs among sap proteins in the course of herbivory or infection. Here we discuss a variety of functions for laticifer and latex in plant defense. We propose that latex peptidases build the front line of defense against herbivores or pathogens.

Production and characterization of collagenase from a new Amazonian Bacillus cereus strain

A new collagenase producing a strain of Bacillus cereus, isolated from the pollen of a bee of Amazon Region (Brazil), had its enzyme characterized and the production medium composition and culture conditions enhanced. A two-level design on three factors, namely initial medium pH, the substrate (gelatin) concentration and agitation intensity, allowed identifying the first two variables as the most significant ones, while a central composite design (CCD) was subsequently used to identify their optimal levels. Statistics highlighted maximized collagenolytic activity when substrate concentration and initial medium pH were selected at their highest levels (positive effects), whereas agitation intensity at the lowest (negative effect). Triplicate runs performed under predicted optimal conditions (pH 7.8 and 1.7% gelatin concentration) yielded a collagenolytic activity (305.39 ± 5.15 U) 4.6- to 15-fold those obtained with the preliminary design. The enzyme displayed optimum activity at 45 °C and pH 7.2, was stable over wide ranges of pH values and temperatures (7.2-11.0 and 25-50 °C, respectively) and was strongly inhibited by 10 mM phenylmethylsulphonyl fluoride. The zymogram showed two prominent bands at 50 and 76 kDa. These results are a first attempt to elucidate the features of this new collagenase, its production conditions, and possible scale-up.

A cysteine protease from the latex of Ficus benjamina has in vitro anthelmintic activity against Haemonchus contortus

Abstract Haemonchus contortus is a gastrointestinal nematode that is responsible for high mortality rates in ruminant herds. The resistance of nematodes to synthetic anthelmintics is widespread and requires a continuous search for new bioactive molecules, such as proteins. The objective of this study was to evaluate the anthelmintic potential of a protease purified from the latex of Ficus benjamina against H. contortus . Fresh latex was collected from plants via small incisions in the green stems, the rubber was removed by centrifugation, and the latex protein extract (LPE) was obtained. After LPE fractionation with ammonium sulfate and chromatography of the fraction containing the highest proteolytic activity on CM-cellulose, a cysteine protease (FbP) was purified. FbP has a molecular mass of approximately 23.97 kDa, and its proteolytic activity was stable between pH 6.0 and pH 10 and over a broad temperature range, with optimum activity at 60 °C. FbP inhibited both the development and exsheathment of H. contortus larvae, with 50% effective concentrations of 0.26 and 0.79 mg/mL, respectively. We conclude that this cysteine protease from F. benjamina latex with anthelmintic activity against H. contortus could be a promising alternative for the development of products for use in parasite control programmes.

Autolysis of bovine skin, its endogenous proteases, protease inhibitors and their effects on quality characteristics of extracted gelatin

The autolysis of pretreated bovine skin (PBS) (treated with 0.1 M NaOH and 1% HCl), its endogenous proteases, inhibitors and their effects on quality attributes of gelatin were examined. PBS was subjected to different temperatures (20-90 °C) and pH (2-9) and treated with different protease inhibitors. Maximum autolytic activity of PBS was observed at 40 °C and pH 5. Ethylene-bis (oxyethylenenitrilo) tetraacetic acid (EGTA) was the most effective in impeding the degradation of γ-, β- and α- chains of PBS protein indicating that metallocollagenases were the predominant endogenous proteases in bovine skin. Gelatin was extracted in the absence (GAE) and presence (GPE) of EGTA, and EGTA with papain enzyme (GPEP). GPEP had a higher yield and lower gel strength than GEA and GPE. Metallocollagenases partook in the degradation of gelatin thereby affecting its functional properties. Pretreating PBS with or without EGTA, and papain influenced the quality attributes of gelatin.

Purification and characterization of a novel extracellular serine-protease with collagenolytic activity from Aspergillus tamarii URM4634

An extracellular serine-protease from Aspergillus tamarii URM4634 was purified and characterized. The possibility of using Aspergillus tamarii URM4634 protease in detergent formulations and collagenolytic activity was investigated. The protease demonstrated excellent stability at pH range 7.0-11.0, the optimum being at pH 9.0. The enzyme was stable at 40 °C for 180 min, enhanced by Mg⁺⁺ and Ca⁺⁺, but inhibited by Zn⁺⁺, and strongly inhibited by phenylmethylsulfonyl fluoride (PMSF), suggested as serine-protease. The azocasein substrate result showed Km = 0.434 mg/mL and V_max = 7.739 mg/mL/min. SDS-PAGE and azocasein zymography showed that the purified alkaline protease (2983.8 U/mg) had a molecular mass of 49.3 kDa. The enzyme was purified by column chromatography using Sephadex A50 resin. The proteolytic activity was activated by SDS (sodium dodecyl sulfate), Tween-80, Tween 20 and Triton-100. This study demonstrated that A. tamarii URM4634 protease has potent, stable and compatible collagenolytic activity to the desired level in local laundry detergent brands compared with similar enzymes produced by solid-state fermentation. This protease can thus be chosen as an option in both the food industry to tenderization meat and the detergent industry to washing process.

A critical review on serine protease: Key immune manipulator and pathology mediator

Proteolytic activity is fundamental to survival, so it is not surprising that all living organisms have proteases, especially seine protease. This enzyme in its numerous isoforms and homologues, constitutes the quintessential offence and defence factors, in the form of surface proteins, secreted molecules, gut digestive enzymes, venom in specialised glands or plant latex, among other manifestations. Occurring as trypsin, chymotrypsin, elastase, collagenase, thrombin, subtilisin etc., it mediates a diverse array of functions, including pathological roles as inflammatory, coagulatory to haemorrhagic. This review emphasizes that despite the superficial differences in mechanisms, most health issues, be they infectious, allergic, metabolic, or neural have a common conduit. This enzyme, in its various glycosylated forms leads to signal misinterpretations, wreaking havoc. However, organisms are endowed with serine protease inhibitors which might restrain this ubiquitous yet deleterious enzyme. Hence, serine proteases-driven pathogenesis and antagonising role of inhibitors is the focal point of this critical review.

Box-Behnken analysis and storage of spray-dried collagenolytic proteases from Myceliophthora thermophila submerged bioprocess

Enzymes do not have long-term storage stability in soluble forms, thus drying methods could minimize the loss of enzymatic activity, the spray dryer removes water under high temperatures and little time. The aims of this study were to improve the stability of enzymatic extract from Myceliophthora thermophila for potential applications in industry and to evaluate the best conditions to remove the water by spray drying technique. The parameters were tested according to Box-Behnken and evaluated by analysis of variance (ANOVA), all the parameters measured were found to influence the final enzyme activity and spray drying process yield ranged from 38.65 to 63.75%. Enzyme powders showed increased storage stability than extract and maintained about 100% of collagenolytic activity after 180 days of storage at 30°C. The results showed that the microbial enzymes maintained activity during the spray drying process and were stable during long-term storage; these are promising characteristics for industrial applications.

Antibacterial serine protease from Wrightia tinctoria: Purification and characterization

A serine protease was purified from the leaves of Wrightia tinctoria by sequential flow through method comprising screening, optimization, ammonium sulfate precipitation, gel filtration and ion exchange column chromatography. The yield and purification fold obtained were 11.58% and 9.56 respectively. A single band of serine protease was visualized on SDS-PAGE and 2-D gel electrophoretic analyses were revealed with the molecular mass of 38.5 kDa. Serine protease had an optimum pH of 8.0 and was stable at 45°C with high relative protease activity. The addition of metal ions such as Mg2+ and Mn2+ exhibits a high relative activity. Serine protease had a potent antibacterial activity against both Gram-positive and Gram-negative bacteria. A 10 μg/ml of serine protease was tested against S. aureus, M. luteus, P. aeruginosa and K. pneumoniae which had 21, 20, 18 and 17 mm of zone of inhibition respectively. Serine protease from W. tinctoria degrades the peptidoglycan layer of bacteria which was visualized by transmission electron microscopic analysis.

Characterization of Novel Collagenolytic Proteases

Collagenolytic proteases have many potential applications in different areas of science, industry, and medicine. The determination of the activity of such proteins is paramount to their application. Here, we describe methods which can be applied to determine the activity and some basic characteristics of potential collagenases.

Characterisation of general proteolytic, milk clotting and antifungal activity of Ficus carica latex during fruit ripening

BACKGROUND

The physiological role of fig latex is to protect the plant from pathogens. Latex is a rich source of proteases, predominantly ficin. Fig latex also contains collagenolytic protease and chitinolytic enzymes. Our aim was to investigate changes in protein composition, enzyme and antifungal activities of fig latex during fruit ripening.

RESULTS

Comparison of latex samples in different time periods showed a uniform increase of protein concentration in chronological order. The content of collagenolytic protease did not differ significantly in the latex samples, while the content of ficin decreased. Ficin-specific activity towards casein was the highest at the beginning of fruit development (about 80 U mg(-1)). Specific milk clotting activity increased as well as the abundance of casein band in the clots. Specific chitinolytic activity at the beginning of flowering was 6.5 times higher than the activity in the period when fruits are ripe. Antifungal activity is the most extensive in spring.

CONCLUSION

Ficin forms with different casein specificities are present in different proportions during fruit ripening, which is of importance for applications in the dairy industry. The protection mechanism against insects and fungi, which relies on chitinolytic activity, is the most important in the early phases of flowering and is replaced with other strategies over time.

Microbial collagenases: challenges and prospects in production and potential applications in food and nutrition

Microbial collagenases are promising enzymes in view of their extensive industrial and biological applications.

Fourier transform infrared spectroscopy provides an evidence of papain denaturation and aggregation during cold storage

Papain is a cysteine protease with wide substrate specificity and many applications. Despite its widespread applications, cold stability of papain has never been studied. Here, we used differential spectroscopy to monitor thermal denaturation process. Papain was the most stabile from 45 °C to 60 °C with ΔG°321 of 13.9±0.3 kJ/mol and Tm value of 84±1 °C. After cold storage, papain lost parts of its native secondary structures elements which gave an increase of 40% of intermolecular β-sheet content (band maximum detected at frequency of 1621 cm(-1) in Fourier transform infrared (FT-IR) spectrum) indicating the presence of secondary structures necessary for aggregation. The presence of protein aggregates after cold storage was also proven by analytical size exclusion chromatography. After six freeze-thaw cycles around 75% of starting enzyme activity of papain was lost due to cold denaturation and aggregation of unfolded protein. Autoproteolysis of papain did not cause significant loss of the protein activity. Upon the cold storage, papain underwent structural rearrangements and aggregation that correspond to other cold denatured proteins, rather than autoproteolysis which could have the commercial importance for the growing polypeptide based industry.