RESUMEN
Proline-rich polypeptides (PRPs complex also known as COLOCO®, Colostrinin®) consist of low-molecular weight peptides ranging up to 10 kDa, isolated from the bovine colostrum obtained up to 48 h postpartum. PRPs have been shown to affect processes involved in inflammation, brain aging, and neurodegeneration. The aim of this study was to investigate the effect of Colostrinin® (COLOCO®) on the cognitive abilities of healthy volunteers in three different age groups using the CANTAB tool in a double-blind randomized placebo-controlled study. BDNF serum level was used as a physicochemical marker of improvement of the cognitive skills. Three hundred and sixty-one healthy volunteers were divided into three study groups aged 18-24, 25-54, and 55-75; each group was then divided into two subgroups which took either placebo or tested lozenge with 120 µg of PRPs for the period of 4 months. The CANTAB battery test was used to measure the efficacy of PRP in the context of cognitive functioning. After the treatment with COLOCO®, we observed differences within MoCA score in the oldest patients, improvement in DMS and drop in PAL scores within the youngest group, drop in RTI and improvement in RVP scores within the middle-aged group. It was observed that serum BDNF level increased in all study groups which confirms cognitive improvement. In conclusion, we have shown that Colostrinin® exhibits cognitive enhancing effects, probably through the modulation of BDNF concentrations.
RESUMEN
PURPOSE: Cystatin C plays an important role in the course of neurodegenerative diseases and has a beneficial effect through inhibiting cysteine proteases and amyloid-ß aggregation. It also induces proliferation and autophagy. Cystatin isolated from chicken egg white, called ovocystatin, has been widely used in the medical and pharmaceutical research due to its structural and biological similarities to human cystatin C. The aim of this study was to assess the effect of administering ovocystatin on the development of dementia-specific cognitive deficits in APP/PS1 transgenic mice. MATERIALS/METHODS: The study was conducted on transgenic B6C3-Tg(APPswe,PSEN1dE9)85Dbo/Mmjax mice. Ovocystatin was administered to four-month-old transgenic (AD) and wild type (NCAR) mice in drinking water for 24 weeks (at a dose of 40 and 4 µg/ mouse). The locomotor activity and cognitive functions were determined using an actimeter and the Morris water maze test, respectively. RESULTS: The results of the study indicate that ovocystatin has a beneficial effect on the cognitive functions in APP/PS1 transgenic mice. The strongest effects of ovocystatin were found in the group of AD mice, where ovocystatin was administered in drinking water at a dose of 40 µg/mouse (p < 0.05). Mice from the AD group swam statistically significantly further in the target zone during the trial in the Morris water maze compared to the AD (vehiculum) group (p < 0.05). CONCLUSIONS: The obtained results encourage further research into the protective effect, which may be used as an adjuvant in the treatment of deteriorating cognitive functions.
Asunto(s)
Péptidos beta-Amiloides/genética , Disfunción Cognitiva/tratamiento farmacológico , Presenilina-1/genética , Animales , Peso Corporal/efectos de los fármacos , Pollos , Disfunción Cognitiva/fisiopatología , Humanos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Péptidos/farmacología , Péptidos/uso terapéuticoRESUMEN
Colostrum and milk are the initial mammalian nourishment and rich reservoir of essential nutrients for newborn development. Bioactive peptides isolated from natural sources, such as colostrum, serve as endogenous regulators and can be used as alternative therapeutic agents in the treatment of neurodegenerative diseases. One example is the previously unknown NP-POL nonapeptide isolated from Colostrinin. In the present study, we investigated a method of NP-POL nonapeptide isolation using Bio-Gel P2 molecular sieve chromatography. We showed the protective effect of NP-POL on 6-hydroxydopamine- (6-OHDA-) induced neurotoxicity using rat adrenal pheochromocytoma (PC12 Tet On) cells. Treatment of PC12 cells with NP-POL nonapeptide reduced 6-OHDA-induced apoptosis and caused transient phosphorylation of extracellular signal-regulated kinases (ERK 1/2), which were shown to promote cell survival. NP-POL nonapeptide also protected neuronal cells against oxidative injury induced by 6-OHDA. These results showed a potential use of NP-POL in the therapy of Parkinson's disease.
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Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Oligopéptidos/aislamiento & purificación , Oligopéptidos/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Neoplasias de las Glándulas Suprarrenales/tratamiento farmacológico , Neoplasias de las Glándulas Suprarrenales/metabolismo , Neoplasias de las Glándulas Suprarrenales/patología , Secuencia de Aminoácidos , Animales , Apoptosis/efectos de los fármacos , Bovinos , Calostro/química , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Fármacos Neuroprotectores/química , Oligopéptidos/química , Células PC12 , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Feocromocitoma/tratamiento farmacológico , Feocromocitoma/metabolismo , Feocromocitoma/patología , Ratas , Especies Reactivas de Oxígeno/metabolismo , OvinosRESUMEN
BACKGROUND: The positive effect of human cystatin C on the development of Alzheimer's disease has been reported, as it inhibits the formation of ß-amyloid oligomers and amyloidogenesis. Cystatin C has been found to have a neuroprotective effect by inhibiting cysteine proteases, inducing autophagy and neurogenesis. There is a growing interest in the procognitive properties of colostrum-based specimens, which could delay dementia and ameliorate memory deterioration. OBJECTIVES: The aim of the study was to evaluate the influence of ovocystatin and a Coloco peptide complex on the cognitive functions in reference to Colostrinin, using a model of young (4 month-old) and old (10-month-old) Wistar rats. MATERIAL AND METHODS: In the present study, the effects of ovocystatin [100 µg/rat] and the Coloco peptide [4 µg/rat]derived from colostrum were assessed with respect to the reference specimen, Colostrinin [4 µg/rat]. The specimens were administered intraperitoneally and orally for 12 days. Cognitive functions were assessed using the Morris water maze (MWM). RESULTS: The group of young rats that received ovocystatin orally obtained significantly better results in the MWM compared to the placebo group (p < 0.05). Similarly, the group of young rats receiving Coloco orally obtained better results in the MWM compared to the placebo group and to the group of rats receiving Colostrinin (p < 0.05). There were no statistically significant differences in the oral and intraperitoneal administration of ovocystatin, Coloco and Colostrinin in the group of old rats. CONCLUSIONS: The obtained results suggest that oral administration of ovocystatin and Coloco has beneficial effects on the cognitive functions of young rats.
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Cognición/efectos de los fármacos , Calostro/química , Inhibidores de Cisteína Proteinasa/farmacología , Factores Inmunológicos/farmacología , Péptidos/farmacología , Animales , Péptidos y Proteínas de Señalización Intercelular , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Modelos Animales , Actividad Motora/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
The study aimed to assess the effect of the polypeptide Y complex (Yolkin), isolated from chicken egg yolk, on behavioural and cognitive functions. It also aimed to compare this activity with colostrum-derived substances (Colostrinin, Coloco), which have a confirmed impact on learning and memory. In the study, the effect of Yolkin, administered to rats of different ages, who performed various tasks involving spatial and episodic memory, motor functions and exploratory behavior, was assessed. The experiment was carried out in rats which were 6 and 12 months old. Two different doses of the studied specimens based on previous comparative studies and two different routes of administration (oral and retroperitoneal) were used. A series of behavioural tests were carried out, including an open field test, a novel object recognition test and a Morris water maze. They were used to evaluate the impact of the studied specimen on improving locomotor function and exploratory behaviour, preventing their decline and assess the functioning of episodic and spatial memory in aging rats. The administration of Yolkin gave distinct effects compared to colostrum-derived substances, although confirmed its suggested pro-cognitive action. Therefore, it may be used to enhance cognitive functions and inhibit the progression of dementia in the course of neurodegenerative disorders.
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Proteínas Aviares/administración & dosificación , Proteínas Aviares/inmunología , Trastornos del Conocimiento/inmunología , Cognición/fisiología , Calostro/inmunología , Proteínas del Huevo/administración & dosificación , Proteínas del Huevo/inmunología , Yema de Huevo/inmunología , Envejecimiento , Animales , Peso Corporal , Pollos , Sistema Inmunológico , Inmunomodulación/inmunología , Masculino , Aprendizaje por Laberinto , Memoria , Ratas , Ratas WistarRESUMEN
The aim of this study was to analyze the antibacterial activity of hen egg white cystatin against selected Escherichia coli strains. We used a monomeric solution of hen egg white cystatin in bovine serum albumin (BSA) with added phosphate buffered saline (PBS), and three test strains: Escherichia coli ATCC 23811, Escherichia coli ATCC 8739 and Escherichia coli ATCC 25922. The effect of cystatin against the tested strains was determined on the basis of minimal inhibitory concentration (MIC) and survival curves of the microorganisms in a cystatin-containing environment during incubation at various temperatures. Our study confirmed the activity of cystatin against the analyzed Escherichia coli strains. taining environment, as compared to control samples incubated in a ovocystatin-deficient medium. Depending on the incubation temperature (20 degrees C or 37 degrees C) the reduction persisted up to 12 hours after incubation.
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Antibacterianos/farmacología , Escherichia coli/clasificación , Escherichia coli/efectos de los fármacos , Animales , Antibacterianos/química , Pollos , Clara de Huevo/química , Péptidos/química , Péptidos/farmacología , Factores de TiempoRESUMEN
In the present study angiotensin I-converting enzyme (ACE) inhibitory peptides were isolated from egg-yolk protein preparation (YP). Enzymatic hydrolysis conducted using unconventional enzyme from Cucurbita ficifolia (dose: 1000 U/mg of hydrolyzed YP (E/S (w/w)=1:7.52)) was employed to obtain protein hydrolysates. The 4-h hydrolysate exhibited a significant (IC50=482.5 µg/mL) ACE inhibitory activity. Moreover, hydrolysate showed no cytotoxic activity on human and animal cell lines which makes it a very useful multifunctional method for peptide preparation. The compiled isolation procedure (ultrafiltration, size-exclusion chromatography and RP-HPLC) of bioactive peptides from YP hydrolysate resulted in obtaining peptides with the strong ACE inhibitory activity. One homogeneous and three heterogeneous peptide fractions were identified. The peptides were composed of 9-18 amino-acid residues, including mainly arginine and leucine at the N-terminal positions. To confirm the selected bioactive peptide sequences their analogs were chemically synthesized and tested. Peptide LAPSLPGKPKPD showed the strongest ACE inhibitory activity, with IC50 value of 1.97 µmol/L. BIOLOGICAL SIGNIFICANCE: Peptides with specific biological activity can be used in pharmaceutical, cosmetic or food industries. Because of their potential role as physiological modulators, as well as theirhigh safety profile, they can be used as natural pharmacological compounds or functional food ingredients. The development of biotechnological solutions to obtain peptides with desired biological activity is already in progress. Studies in this area are focused on using unconventional highly specific enzymes and more efficient methods developed to conduct food process technologies. Natural peptides have many advantages. They are mainly toxicologically safe, have wide spectra of therapeutic actions, exhibit less side effects compared to synthetic drugs and are more efficiently absorbed in the intestinal tract. The complexity of operation of large scale technologies and high cost of purification techniques are limiting factors to the commercialization of food-derived bioactive peptides. Research on the isolation of bioactive peptides in order to reduce the processing time and costs is continuously developing. Bioactive peptides can also be released from protein by-products of the food industry, which reduce the substrate expense and production cost as well as provide the added advantage of an efficient waste disposal. Moreover, proteins as precursors of food-derived peptides are well-tolerated by the human body and therefore their application in drug development may reduce costs and duration of toxicological studies during research, development and clinical trials.
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Inhibidores de la Enzima Convertidora de Angiotensina/química , Cucurbita/enzimología , Proteínas del Huevo/química , Péptido Hidrolasas/química , Péptidos/química , Proteínas de Plantas/química , Secuencia de Aminoácidos , Inhibidores de la Enzima Convertidora de Angiotensina/aislamiento & purificación , Cucurbita/clasificación , Proteínas del Huevo/aislamiento & purificación , Activación Enzimática , Datos de Secuencia Molecular , Péptidos/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Especificidad de la EspecieRESUMEN
In the hen immune system the egg content plays as significant a role in the development of the chick as colostrum does in newborn mammals. One of the most important proteins in this system seems to be the main yolk immunoglobulin IgY. It has been shown that IgY is accompanied by an immunostimulatory polypeptide complex named yolkin. In this report the biological activities of yolkin separated by means of four different procedures are presented. It was shown that yolkin acts as an inducer rather than a modulator of cytokine and nitric oxide release, and does not participate in the protection of cells against destructive effects of reactive oxygen species. However, using the perchloric acid procedure it is possible to obtain a peptide fraction with higher inducing activity, stronger antioxidant properties and ability to decrease the NO level induced by lipopolysaccharide. The results obtained show that it is feasible to select one of the presented methods of yolkin isolation that yields a product of particular activity. The properties of yolk peptides not only indicate their roles in the development of chicks, but can also be useful for the regulation of some immunological disturbances.
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Métodos Analíticos de la Preparación de la Muestra/métodos , Yema de Huevo/química , Inmunoglobulinas/inmunología , Péptidos/inmunología , Péptidos/aislamiento & purificación , Animales , Células Cultivadas , Pollos , Citocinas/inmunología , Yema de Huevo/inmunología , Humanos , Inmunoglobulinas/química , Leucocitos Mononucleares/inmunología , Ratones , Péptidos/químicaRESUMEN
The protein mixture of cytokine-inducing activity accompanying chicken immunoglobulin Y, named yolkin, consists of several peptides of molecular weight (MW) ranging from over 1 to 35 kDa. Yolkin and its constituent peptides were found to be efficient inducers of interleukin (IL)-1ß, IL-6 and IL-10 secretion. N-terminal amino acid sequences of eight of the electrophoretically purified yolkin constituents revealed that all of them are homological to some fragments of the C-terminal domain of vitellogenin II. The fractions of MW about 4 and 12 kDa are free of carbohydrates and start at position 1732 in the vitellogenin amino acid sequence; whereas the other fractions (MW about 16, 19, 23, 29, 32 and 35 kDa) appeared to be glycoproteins corresponding to the amino acid sequence of vitellogenin starting at position 1572. From these data, it is concluded that yolkin most likely represents vitellogenin-derived peptides that possess cytokine-inducing activity and are, at least partially, responsible for such properties of separated immunoglobulin Y preparation. This finding reveals a new role for vitellogenin as a reservoir of polypeptides that may play an important role in the innate immune system of the developing embryo.
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Pollos/inmunología , Yema de Huevo/inmunología , Inmunoglobulinas/inmunología , Interleucinas/inmunología , Secuencia de Aminoácidos , Animales , Electroforesis en Gel de Poliacrilamida/veterinaria , Femenino , Humanos , Inmunoglobulinas/química , Interleucinas/sangre , Datos de Secuencia Molecular , Análisis de Secuencia de Proteína , Estadísticas no ParamétricasRESUMEN
Enzymatic hydrolysis led to improve functional properties and biological activity of protein by-products, which can be further used as protein ingredients for food and feed applications. The effects of proteolytic enzyme modification of egg-yolk protein preparation (YP) and white protein preparation (WP), obtained as the by-products left during the course of lecithin, lysozyme, and cystatin isolation on their biological and functional properties, were evaluated by treating a commercial Neutrase. The antihypertensive and antioxidative properties of YP and WP hydrolysates were evaluated based on their angiotensin-converting enzyme (ACE)-inhibitory activity and radical scavenging (DPPH) capacity, ferric reducing power, and chelating of iron activity. The functionality of obtained hydrolysates was also determined. Neutrase caused a degree of hydrolysis (DH) of YP and WP by-products: 27.6% and 20.9%, respectively. In each of them, mixture of peptides with different molecular masses were also observed. YP hydrolysate showed high levels of antioxidant activity. The scavenging capacity, ferric reducing power, and chelating capacity were observed at the level: 0.44 µmol/L Trolox mg(-1), 177.35 µg Fe(2+) mg(-1), and 549.87 µg Fe(2+) mg(-1), respectively. YP hydrolysate also exhibited significant ACE-inhibitory activity, in which the level was 59.2 µg. Protein solubility was significantly improved as the DH increased. WP hydrolysate showed high water-holding capacity of 43.2. This study indicated that YP and WP hydrolysates could be used in foods as natural antioxidants and functionality enhancers.
RESUMEN
Numerous studies have shown that food proteins may be a source of bioactive peptides. Those peptides are encrypted in the protein sequence. They stay inactive within the parental protein until release by proteolytic enzymes (Mine and Kovacs-Nolan in Worlds Poult Sci J 62(1):87-95, 2006; Hartman and Miesel in Curr Opin Biotechnol 18:163-169, 2007). Once released the bioactive peptides exhibit several biofunctionalities and may serve therapeutic roles in body systems. Opioid peptides, peptides lowering high blood pressure, inhibiting platelet aggregation as well as being carriers of metal ions and peptides with immunostimulatory, antimicrobial and antioxidant activities have been described (Hartman and Miesel in Curr Opin Biotechnol 18:163-169, 2007). The biofunctional abilities of the peptides have therefore aroused a lot of scientific, technological and consumer interest with respect to the role of dietary proteins in controlling and influencing health (Möller et al. in Eur J Nutr 47(4):171-182, 2008). Biopeptides may find wide application in food production, the cosmetics industry as well as in the prevention and treatment of various medical conditions. They are manufactured by chemical and biotechnological methods (Marx in Chem Eng News 83(11):17-24. 2005; Hancock and Sahl in Nat Biotechnol 24(12):1551-1557, 2006). Depending on specific needs (food or pharmaceutical industry) different degrees of peptide purifications are required. This paper discusses the practicability of manufacturing bioactive peptides, especially from food proteins.
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Péptidos/química , Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Humanos , Datos de Secuencia Molecular , Péptidos/síntesis química , Péptidos/genética , Proteínas/química , Relación Estructura-ActividadRESUMEN
The increasing incidence of fungal infections together with the emergence of strains resistant to currently available antifungal drugs calls for the development of new classes of antimycotics. Naturally occurring antifungal proteins and peptides are of interest because of low toxicity, immunomodulatory potential and mechanisms of action distinct from those of currently available drugs. In this study, the potent antifungal activity of cystatin, affinity-purified from chicken egg white (CEWC), against the most frequent human fungal pathogens of the genus Candida was identified and characterised. CEWC inhibited the growth of azole-sensitive Candida albicans isolates with minimal inhibitory concentration (MIC) values ranging from 0.8 to 3.3 micromol l(-1), a potency comparable with those of fluconazole and histatin 5, the antimicrobial peptide of the human saliva. Similarly to histatin 5, CEWC activity was not compromised in azole-resistant isolates overproducing the multidrug efflux transporters Cdr1p and Cdr2p and did not antagonise fluconazole or amphotericin B. CEWC had candidacidal activity, as revealed by the time-kill assay, and, similarly to histatin 5, completely inhibited the growth at supra-MIC concentrations. This was in contrast to the fungistatic effect and trailing growth observed with fluconazole. CEWC inhibited the growth of Candida parapsilosis and Candida tropicalis at similar concentrations, whereas Candida glabrata was more resistant to CEWC.
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Antifúngicos/farmacología , Azoles/farmacología , Candida/efectos de los fármacos , Cistatinas/farmacología , Farmacorresistencia Fúngica , Óvulo/química , Anfotericina B/farmacología , Animales , Antifúngicos/aislamiento & purificación , Candida/crecimiento & desarrollo , Pollos , Cromatografía de Afinidad , Cistatinas/aislamiento & purificación , Fluconazol/farmacología , Proteínas Fúngicas/biosíntesis , Expresión Génica , Histatinas/farmacología , Proteínas de Transporte de Membrana/biosíntesis , Pruebas de Sensibilidad MicrobianaRESUMEN
Low-molecular-mass trypsin inhibitor (clTI-1; chicken liver Trypsin Inhibitor-1) was purified from chicken liver by extraction with perchloric acid, ammonium sulfate precipitation, a combination of ethanol-acetone fractionation followed by gel filtration, ion-exchange chromatography and RP-HPLC on a C18 column. The inhibitor occurs in two isoforms with molecular masses of 5938.56 and 6026.29 Da (determined by MALDI TOFF mass spectrometry). The complete amino acid sequences of both isoforms were determined (UniProtKB/Swiss-Prot P85000; ISK1L_CHICK). The inhibitor shows a high homology to Kazal-type family inhibitors, especially to trypsin/acrosin inhibitors and pancreatic secretory trypsin inhibitors. clTI-1 inhibits both bovine and porcine trypsin (K(a)=1.1 x 10(9) M(-1) and 2.5 x 10(9) M(-1), respectively). Significant differences were shown in the inhibition of the anionic and cationic forms of chicken trypsin (K(a)=4.5 x 10(8) M(-1) and 1.2 x 10(10) M(-1)). Weak interaction with human plasmin (K(a)=1.2 x 10(7) M(-1)) was also revealed.
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Pollos , Hígado/química , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/química , Inhibidores de Serina Proteinasa/aislamiento & purificación , Inhibidor de Tripsina Pancreática de Kazal/química , Inhibidor de Tripsina Pancreática de Kazal/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Humanos , Datos de Secuencia Molecular , Inhibidores de Serina Proteinasa/farmacología , Inhibidor de Tripsina Pancreática de Kazal/farmacologíaRESUMEN
Four forms of chymotrypsin (Chtr1, Chtr2, Chtr3, Chtr4), one form of trypsin and one form of elastase were purified from a slightly alkaline extract of ostrich (Struthio camelus) pancreas. The zymogens in the crude extract were activated with immobilized trypsin and then separated by affinity chromatography using immobilized inhibitors and ion exchange chromatography. One of the purified forms of chymotrypsin (Chtr1) exhibited an unusual interaction with the highly selective protein trypsin inhibitor from Cucurbita maxima (CMTI). Interactions with other protein trypsin inhibitors such as basic pancreatic trypsin inhibitor (BPTI), soybean trypsin inhibitor (STI), trypsin inhibitors from Cyclanthera pedata (CyPTI), Cucurbita pepo (CPTI), Cucurbita pepo var. giramontia (CPGTI) and Linum usitatissimum (LUTI) were also investigated. This study demonstrated the affinity of Chtr1 to inhibitors containing Arg at P1 position. Studies of substrate specificity of Chtr1 using oxidized B-chain of insulin revealed four susceptible bonds: Tyr15-Leu16, Phe24-Phe25, Phe25-Tyr26 and, surprisingly, Arg22-Gly23. The amino acid composition, as well as the first 13 residues of the N-terminal amino acid sequence, was determined. Studies of ostrich elastase showed that it can interact with immobilized CMTI in the presence of 5 M NaCl. This unusual characteristic is reported for the first time and suggests that elastase specificity depends on ionic strength. The kinetic constants K(M), k(cat) and k(cat)/K(M) for purified ostrich trypsin, chymotrypsin 4 and elastase were also determined.
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Quimotripsina/aislamiento & purificación , Quimotripsina/metabolismo , Páncreas/enzimología , Struthioniformes/metabolismo , Inhibidores de Tripsina/metabolismo , Secuencia de Aminoácidos , Animales , Cromatografía de Afinidad , Cromatografía por Intercambio Iónico , Quimotripsina/análisis , Quimotripsina/química , Electroforesis , Cinética , Datos de Secuencia Molecular , Elastasa Pancreática/antagonistas & inhibidores , Elastasa Pancreática/aislamiento & purificación , Elastasa Pancreática/metabolismo , Unión Proteica , Especificidad por Sustrato , Tripsina/aislamiento & purificación , Tripsina/metabolismoRESUMEN
The relatively little-investigated entomopathogen Conidiobolus coronatus secretes several proteinases into culture broth. Using a combination of ion-exchange and size-exclusion chromatography, we purified to homogeneity a serine proteinase of Mr 30,000-32,000, as ascertained by SDS-PAGE. The purified enzyme showed subtilisin-like activity. It very effectively hydrolyzed N-Suc-Ala(2)-Pro-Phe-pNa with a Km-1.36 x 10(-4) M and Kcat-24 s(-1), and N-Suc-Ala(2)-Pro-Leu-pNa with Km-6.65 x 10(-4) M and Kcat-11 s(-1). The specificity index k(cat)/K(m) for the tested substrates was calculated to be 176,340 s(-1) M(-1) and 17,030 s(-1) M(-1), respectively. Using oxidized insulin B chain as a substrate, the purified proteinase exhibited specificity to aromatic and hydrophobic amino-acid residues, such as Phe, Leu, and Gly at the P1 position, splitting primarily the peptide bonds: Phe(1)-Val(2), Leu(15)-Tyr(16), and Gly(23)-Phe(24). The proteinase appeared to be sensitive to the specific synthetic inhibitors of the serine proteinases DFP (diisopropyl flourophosphate) and PMSF (phenyl-methylsulfonyl fluoride) as well as to some naturally occurring protein inhibitors of chymotrypsin. It is worth noting that the enzyme exhibited the highest sensitivity to inhibition by AMCI-1 (with an association constant of 3 x 10(10) M(-1)), an inhibitor of cathepsin G/chymotrypsin from the larval hemolymph of Apis mellifera, reinforcing the possibility of involvement of inhibitors from hemolymph in insect innate immunity. The substrate specificity and proteinase inhibitor effects indicate that the purified proteinase from the fermentation broth of Conidiobolus coronatus is a subtilisin-like serine proteinase.
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Conidiobolus/enzimología , Serina Endopeptidasas/aislamiento & purificación , Serina Endopeptidasas/metabolismo , Animales , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Hemolinfa/metabolismo , Concentración de Iones de Hidrógeno , Insulina/metabolismo , Cinética , Inhibidores de Serina Proteinasa/farmacología , Especificidad por SustratoRESUMEN
Recent advances in protein separation technology have allowed for the isolation of whey proteins and peptides of significant biological importance. In this study, we report a novel method for isolation and purification of the neuroprotective proline-rich polypeptides, also known as Colostrinin (CLN). Although CLN was first isolated from ovine colostrum and characterized as a complex of small molecular peptides, its constituents are present also in other mammal colostrums. The previous purification protocols are very tedious, time consuming, and, due to the diverse characteristics of colostrum, also very difficult to validate. Thus, the aim of this study was to develop a simple protocol with a maximum recovery rate for CLN peptides. Here we demonstrate the two-step extraction/purification method that consists of methanol extraction and ammonium sulfate precipitation as the general principles. When compared with the original material, CLN obtained by this method shows (1) similar pattern of peptides in SDS PAGE, (2) identical amino acid analysis, characterized by high content of proline (22%), a high proportion of nonpolar amino acids, a low percentage of glycine, alanine, arginine, histidine, and no tryptophan, methionine, and cysteine residues, (3) similar pattern of HPLC profiles, and (4) its ability to induce IFN gamma and TNF alpha. More importantly, the protocol for the production of high-quality CLN can be accomplished in less than a 48 h timeframe. In addition, avoidance of excessively harsh conditions preserves the structure and biological activity of the peptides.
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Alcoholes/farmacología , Caseínas/efectos de los fármacos , Péptidos/aislamiento & purificación , Sulfato de Amonio/química , Animales , Cromatografía Líquida de Alta Presión , Calostro , Electroforesis en Gel de Poliacrilamida , Péptidos y Proteínas de Señalización Intercelular , Interferón gamma/metabolismo , Metanol/química , Micelas , Leche/química , Péptidos/farmacología , Conformación Proteica/efectos de los fármacos , Ovinos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
From among a wide variety of protein purification techniques affinity chromatography has proved to be particularly effective for separation of proteolytic enzymes and their inhibitors. In this article, following a general description of affinity adsorbents used for purification of proteinases, we overview a simple separation procedure for some serine proteinases and their inhibitors by way of affinity chromatography in the presence of high NaCl concentration. It has been shown that some highly specific trypsin inhibitors exhibit also antichymotrypsin activity when high concentration of Na(+) but not K(+) or Li(+) ions are present in the reaction mixture. Taking advantage of this phenomenon the virgin forms of trypsin inhibitors from squash seeds, Kazal-type inhibitor from porcine pancreas and alpha(1)-proteinase inhibitor from human and sheep plasma, as an example, were separated using immobilized chymotrypsin or its inactive derivative methylchymotrypsin in the presence of 5 M NaCl.