Comparative venomic profiles of three spiders of the genus Phoneutria

Abstract Background: Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.

Comparative venomic profiles of three spiders of the genus Phoneutria

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)

Toxic systemic reaction after bee stings in a bitch

Background: Bee sting poisonings are common in dogs, and toxic systemic presentation may represent a life-threatening condition. Apis mellifera venom is a complex mixture of melitin, apamine, phospholipase, hyaluronidase and degranulating peptides, that causes local injury at the site of inoculation and multiple organ complications, including hemolysis, kidney injury, muscular damage, cardiovascular and respiratory complications. The present work reports a complete and detailed description of a dog's systemic toxic reaction to bee stings, including history, clinical signs, laboratory findings, emergency care and development, as well as possible association with later immunomediated arthritis. Case: A 6-year-old female German Shepperd suffered multiple bee stings. First care was conducted by a veterinary at the site, where he only received promethazine, meloxicam and dexamethasone. After 24 h and significant progression of symptoms, the animal was forwarded to a specialized veterinary hospital. The patient was evaluated throughout 9 days, and presented intense edema, respiratory distress, tongue necrosis and grade II of acute kidney injury. Extensive laboratory exams were conducted throughout the hospitalization. Main laboratory findings included polycythemia, leukocytosis by neutrophilia and monocytosis, thrombocytopenia and azotemia. Urinalysis evidenced turbid aspect, dark yellow color and intense proteinuria, reinforcing kidney damage. Abdominal ultrasound examination identified blood clots in the bladder, and liver with reduced echogenicity and echotexture, suggesting acute inflammation. Therapy aimed to stabilize the patient, control kidney damage and avoid anaphylaxis. Treatment included intensive care support, promethazine, hydrocortisone, dexamethasone, dipyrone, methadone, metronidazole, ampicillin, clindamycin and tramadol. Following successful treatment, the animal presented immunomediated polyarthritis, possibly associated to both the poisoning and later diagnosed hemoparasitosis (both Erlichia and Babesia). Discussion: Massive bee attacks can cause severe complications, however, data regarding emergency care records are scarce. Based on clinical signs and laboratory findings, the patient presented toxic systemic reaction, including grade II of acute kidney injury and significant cardiorespiratory distress. Another important complication was tongue necrosis, that demanded attention and special supportive care, including feeding tube and specific feed. Treatment also focused in reducing edema and control possible anaphylaxis, providing analgesia and antibiotic therapy. Laboratory findings have been previously described, with evidence of immune-mediated reaction. Follow-up consultations revealed normal parameters, and an unusual presentation of claudication. Investigation concluded that polyarthritis could be responsible for such finding and may be a result of the deposition of immunomediated complexes in the joints, due in this case to the bee poisoning and later positive diagnosis for both Erlichia and Babesia. Systemic reactions to bee stings are complex, and full clinical and laboratory profile aid in both the prognosis and treatment options. Special attention must be given to tongue damage and supportive care is essential for maintaining feeding conditions. Arthritis should be considered as possible complication, reinforcing the importance of follow-up consultations.

The effects of cryopreservation on the acrosome structure, enzyme activity, motility, and fertility of bovine, ovine, and goat sperm

The study was designed to investigate the effects of cryopreservation on bovine, ovine, and goat sperm motility, acrosome structure, enzyme activity, and fertilization ability. Percentage of sperm with hyaluronidase enzyme (HYD) activity was detected by a modified sodium hyaluronate-gelatin membrane. The N-α-benzoyl-DL-arginine-p-nitroanilide (BNPNA) method was used to assess the sperm acrosome enzyme (ACE). The mean percentage of sperm acrosome integrity dropped significantly (P < 0.01) after cryopreservation. The ACE activity of bovine sperm (100.48) was higher (P < 0.01) than that of ovine (57.88) or goat sperm (50.30), while the percentage of sperm with HYD activity of bovine (71.10%) and ovine (67.60%) sperm was higher than that of goat sperm (58.52%) after cryopreservation (P < 0.01). Sperm motility was positively correlated with the activity of the two acrosome enzymes before and after cryopreservation (P < 0.01). Cryopreservation had a negative effect on acrosomal morphology, motility, and acrosomal enzyme activity in their sperm. The fertilization ability of ovine and goat sperm decreased significantly after cryopreservation, but that of frozen bovine sperm did not differ significantly when compared with fresh sperm. There was no significant difference between ovine and goat sperm indices, except for percentage of sperm with HYD activity.

The effects of cryopreservation on the acrosome structure, enzyme activity, motility, and fertility of bovine, ovine, and goat sperm

The study was designed to investigate the effects of cryopreservation on bovine, ovine, and goat sperm motility, acrosome structure, enzyme activity, and fertilization ability. Percentage of sperm with hyaluronidase enzyme (HYD) activity was detected by a modified sodium hyaluronate-gelatin membrane. The N-α-benzoyl-DL-arginine-p-nitroanilide (BNPNA) method was used to assess the sperm acrosome enzyme (ACE). The mean percentage of sperm acrosome integrity dropped significantly (P < 0.01) after cryopreservation. The ACE activity of bovine sperm (100.48) was higher (P < 0.01) than that of ovine (57.88) or goat sperm (50.30), while the percentage of sperm with HYD activity of bovine (71.10%) and ovine (67.60%) sperm was higher than that of goat sperm (58.52%) after cryopreservation (P < 0.01). Sperm motility was positively correlated with the activity of the two acrosome enzymes before and after cryopreservation (P < 0.01). Cryopreservation had a negative effect on acrosomal morphology, motility, and acrosomal enzyme activity in their sperm. The fertilization ability of ovine and goat sperm decreased significantly after cryopreservation, but that of frozen bovine sperm did not differ significantly when compared with fresh sperm. There was no significant difference between ovine and goat sperm indices, except for percentage of sperm with HYD activity.(AU)

Heterologous expression and mutagenesis of recombinant Vespa affinis hyaluronidase protein (rVesA2)

Background:Crude venom of the banded tiger waspVespa affinis contains a variety of enzymes including hyaluronidases, commonly known as spreading factors.Methods:The cDNA cloning, sequence analysis and structural modelling of V. affinis venom hyaluronidase (VesA2) were herein described. Moreover, heterologous expression and mutagenesis of rVesA2 were performed.Results:V. affinis venom hyaluronidase full sequence is composed of 331 amino acids, with four predicted N-glycosylation sites. It was classified into the glycoside hydrolase family 56. The homology modelling exhibited a central core (α/β)7 composed of Asp107 and Glu109, acting as the catalytic residues. The recombinant protein was successfully expressed in E. coli with hyaluronidase activity. A recombinant mutant type with the double point mutation, Asp107Asn and Glu109Gln, completely lost this activity. The hyaluronidase from crude venom exhibited activity from pH 2 to 7. The recombinant wild type showed its maximal activity at pH 2 but decreased rapidly to nearly zero at pH 3 and was completely lost at pH 4.Conclusion:The recombinant wild-type protein showed its maximal activity at pH 2, more acidic pH than that found in the crude venom. The glycosylation was predicted to be responsible for the pH optimum and thermal stability of the enzymes activity.(AU)

Heterologous expression and mutagenesis of recombinant Vespa affinis hyaluronidase protein (rVesA2)

Background:Crude venom of the banded tiger waspVespa affinis contains a variety of enzymes including hyaluronidases, commonly known as spreading factors.Methods:The cDNA cloning, sequence analysis and structural modelling of V. affinis venom hyaluronidase (VesA2) were herein described. Moreover, heterologous expression and mutagenesis of rVesA2 were performed.Results:V. affinis venom hyaluronidase full sequence is composed of 331 amino acids, with four predicted N-glycosylation sites. It was classified into the glycoside hydrolase family 56. The homology modelling exhibited a central core (α/β)7 composed of Asp107 and Glu109, acting as the catalytic residues. The recombinant protein was successfully expressed in E. coli with hyaluronidase activity. A recombinant mutant type with the double point mutation, Asp107Asn and Glu109Gln, completely lost this activity. The hyaluronidase from crude venom exhibited activity from pH 2 to 7. The recombinant wild type showed its maximal activity at pH 2 but decreased rapidly to nearly zero at pH 3 and was completely lost at pH 4.Conclusion:The recombinant wild-type protein showed its maximal activity at pH 2, more acidic pH than that found in the crude venom. The glycosylation was predicted to be responsible for the pH optimum and thermal stability of the enzymes activity.

Proteome of fraction from Tityus serrulatus venom reveals new enzymes and toxins

Background:Tityus serrulatus venom (Ts venom) is a complex mixture of several compounds with biotechnological and therapeutical potentials, which highlights the importance of the identification and characterization of these components. Although a considerable number of studies have been dedicated to the characterization of this complex cocktail, there is still a limitation of knowledge concerning its venom composition. Most of Ts venom studies aim to isolate and characterize their neurotoxins, which are small, basic proteins and are eluted with high buffer concentrations on cation exchange chromatography. The first and largest fraction from carboxymethyl cellulose-52 (CMC-52) chromatography of Ts venom, named fraction I (Fr I), is a mixture of proteins of high and low molecular masses, which do not interact with the cation exchange resin, being therefore a probable source of components still unknown of this venom. Thus, the present study aimed to perform the proteome study of Fraction I from Ts venom, by high resolution mass spectrometry, and its biochemical characterization, by the determination of several enzymatic activities.Methods:Fraction I was obtained by a cation exchange chromatography using 50 mg of crude venom. This fraction was subjected to a biochemical characterization, including determination of L-amino acid oxidase, phospholipase, hyaluronidase, proteases activities and inhibition of angiotensin converting enzyme (ACE) activity. Fraction I was submitted to reduction, alkylation and digestion processes, and the tryptic digested peptides obtained were analyzed in a Q-Exactive Orbitrap mass spectrometer. Data analysis was performed by PEAKS 8.5 software against NCBI database. Results:Fraction I exhibits proteolytic activity and it was able to inhibit ACE activity. Its proteome analysis identified 8 different classes of venom components, among them: neurotoxins (48%), metalloproteinases (21%), hypotensive peptides...(AU)

Dalbergia ecastaphyllum leaf extracts: in vitro inhibitory potential against enzymes related to metabolic syndrome, inflammation and neurodegenerative diseases

For the first time, the anti-hemolytic activity and the enzyme inhibitory activities of Dalbergia ecastaphyllum leaves extracts were tested against α-amylase, α-glucosidase, lipase, acetylcholinesterase, butyrylcholinesterase, tyrosinase and hyaluronidase. The phenolic profile of the obtained extracts was also investigated by high-performance liquid chromatography with photodiode array detection (HPLC-PAD). The extracts showed inhibitory activity against all enzymes evaluated, with the highest inhibitory activity reported for the enzyme hyaluronidase (28.28 ± 2.43 to 72.19 ± 1.40 μg mL-1). The obtained extracts also demonstrate anti-hemolytic activity (52.22 ± 1.62 to 71.17 ± 1.82%). Among the phenolic compounds identified, protocatechuic, vanillic and β-resorcylic acids were the most abundant (1.13 ± 0.06 to 2.53 ± 0.06, 0.90 ± 0.06 to 2.19 ± 0.06 and 1.03 ± 1.62 to 22.11 ± 1.62 mg L-1, respectively). In the statistical analysis, a significant correlation was found between the flavonoids content and all enzymes inhibitory activities. The present study showed that D. ecastaphyllum leaves extracts may have the potential to be used in the therapeutic treatment of several diseases such as Alzheimer, Parkinson, type 2 diabetes mellitus, hyperglycemia, and pigmentation, as well as those associated with oxidative stress.

Proteome of fraction from Tityus serrulatus venom reveals new enzymes and toxins

Tityus serrulatus venom (Ts venom) is a complex mixture of several compounds with biotechnological and therapeutical potentials, which highlights the importance of the identification and characterization of these components. Although a considerable number of studies have been dedicated to the characterization of this complex cocktail, there is still a limitation of knowledge concerning its venom composition. Most of Ts venom studies aim to isolate and characterize their neurotoxins, which are small, basic proteins and are eluted with high buffer concentrations on cation exchange chromatography. The first and largest fraction from carboxymethyl cellulose-52 (CMC-52) chromatography of Ts venom, named fraction I (Fr I), is a mixture of proteins of high and low molecular masses, which do not interact with the cation exchange resin, being therefore a probable source of components still unknown of this venom. Thus, the present study aimed to perform the proteome study of Fraction I from Ts venom, by high resolution mass spectrometry, and its biochemical characterization, by the determination of several enzymatic activities. Methods: Fraction I was obtained by a cation exchange chromatography using 50 mg of crude venom. This fraction was subjected to a biochemical characterization, including determination of L-amino acid oxidase, phospholipase, hyaluronidase, proteases activities and inhibition of angiotensin converting enzyme (ACE) activity. Fraction I was submitted to reduction, alkylation and digestion processes, and the tryptic digested peptides obtained were analyzed in a Q-Exactive Orbitrap mass spectrometer. Data analysis was performed by PEAKS 8.5 software against NCBI database. Results: Fraction I exhibits proteolytic activity and it was able to inhibit ACE activity. Its proteome analysis identified 8 different classes of venom components, among them: neurotoxins (48%), metalloproteinases (21%), hypotensive peptides (11%), cysteine-rich venom protein (9%), antimicrobial peptides (AMP), phospholipases and other enzymes (chymotrypsin and lysozymes) (3%) and phosphodiesterases (2%). Conclusions: The combination of a proteomic and biochemical characterization strategies leads us to identify new components in the T. serrulatus scorpion venom. The proteome of venom´s fraction can provide valuable direction in the obtainment of components in their native forms in order to perform a preliminary characterization and, consequently, to promote advances in biological discoveries in toxinology.(AU)

Highlights in the knowledge of brown spider toxins

Abstract Brown spiders are venomous arthropods that use their venom for predation and defense. In humans, bites of these animals provoke injuries including dermonecrosis with gravitational spread of lesions, hematological abnormalities and impaired renal function. The signs and symptoms observed following a brown spider bite are called loxoscelism. Brown spider venom is a complex mixture of toxins enriched in low molecular mass proteins (440 kDa). Characterization of the venom confirmed the presence of three highly expressed protein classes: phospholipases D, metalloproteases (astacins) and insecticidal peptides (knottins). Recently, toxins with low levels of expression have also been found in Loxosceles venom, such as serine proteases, protease inhibitors (serpins), hyaluronidases, allergen-like toxins and histamine-releasing factors. The toxin belonging to the phospholipase-D family (also known as the dermonecrotic toxin) is the most studied class of brown spider toxins. This class of toxins single-handedly can induce inflammatory response, dermonecrosis, hemolysis, thrombocytopenia and renal failure. The functional role of the hyaluronidase toxin as a spreading factor in loxoscelism has also been demonstrated. However, the biological characterization of other toxins remains unclear and the mechanism by which Loxosceles toxins exert their noxious effects is yet to be fully elucidated. The aim of this review is to provide an insight into brown spider venom toxins and toxicology, including a description of historical data already available in the literature. In this review article, the identification processes of novel Loxosceles toxins by molecular biology and proteomic approaches, their biological characterization and structural description based on x-ray crystallography and putative biotechnological uses are described along with the future perspectives in this field.

Highlights in the knowledge of brown spider toxins

Brown spiders are venomous arthropods that use their venom for predation and defense. In humans, bites of these animals provoke injuries including dermonecrosis with gravitational spread of lesions, hematological abnormalities and impaired renal function. The signs and symptoms observed following a brown spider bite are called loxoscelism. Brown spider venom is a complex mixture of toxins enriched in low molecular mass proteins (4-40 kDa). Characterization of the venom confirmed the presence of three highly expressed protein classes: phospholipases D, metalloproteases (astacins) and insecticidal peptides (knottins). Recently, toxins with low levels of expression have also been found in Loxosceles venom, such as serine proteases, protease inhibitors (serpins), hyaluronidases, allergen-like toxins and histamine-releasing factors. The toxin belonging to the phospholipase-D family (also known as the dermonecrotic toxin) is the most studied class of brown spider toxins. This class of toxins single-handedly can induce inflammatory response, dermonecrosis, hemolysis, thrombocytopenia and renal failure. The functional role of the hyaluronidase toxin as a spreading factor in loxoscelism has also been demonstrated. However, the biological characterization of other toxins remains unclear and the mechanism by which Loxosceles toxins exert their noxious effects is yet to be fully elucidated. The aim of this review is to provide an insight into brown spider venom toxins and toxicology, including a description of historical data already available in the literature. In this review article, the identification processes of novel Loxosceles toxins by molecular biology and proteomic approaches, their biological characterization and structural description based on x-ray crystallography and putative biotechnological uses are described along with the future perspectives in this field.(AU)

Highlights in the knowledge of brown spider toxins

Abstract Brown spiders are venomous arthropods that use their venom for predation and defense. In humans, bites of these animals provoke injuries including dermonecrosis with gravitational spread of lesions, hematological abnormalities and impaired renal function. The signs and symptoms observed following a brown spider bite are called loxoscelism. Brown spider venom is a complex mixture of toxins enriched in low molecular mass proteins (4-40 kDa). Characterization of the venom confirmed the presence of three highly expressed protein classes: phospholipases D, metalloproteases (astacins) and insecticidal peptides (knottins). Recently, toxins with low levels of expression have also been found in Loxosceles venom, such as serine proteases, protease inhibitors (serpins), hyaluronidases, allergen-like toxins and histamine-releasing factors. The toxin belonging to the phospholipase-D family (also known as the dermonecrotic toxin) is the most studied class of brown spider toxins. This class of toxins single-handedly can induce inflammatory response, dermonecrosis, hemolysis, thrombocytopenia and renal failure. The functional role of the hyaluronidase toxin as a spreading factor in loxoscelism has also been demonstrated. However, the biological characterization of other toxins remains unclear and the mechanism by which Loxosceles toxins exert their noxious effects is yet to be fully elucidated. The aim of this review is to provide an insight into brown spider venom toxins and toxicology, including a description of historical data already available in the literature. In this review article, the identification processes of novel Loxosceles toxins by molecular biology and proteomic approaches, their biological characterization and structural description based on x-ray crystallography and putative biotechnological uses are described along with the future perspectives in this field.(AU)

Avaliação da atividade da proteína quinase P34Cdc2 na maturação in vitro de oócitos caninos / Evaluation of p34cdc2 kinase activity in the in vitro maturation of canine oocytes

O controle do ciclo celular é regulado por uma cascata de eventos coordenados que podem atuar influenciando na expressão ou repressão da atividade de proteínas relacionadas a retomada da meiose. Estudos indicam que a atividade dessas proteínas mostra-se tempo-dependente no processo de maturação in vitro (MIV). Esse trabalho teve o objetivo de avaliar a cinética da atividade quinase p34cdc2 durante a MIV de oócitos caninos. Ciência Animal 27(1), 2017. Os ovários foram obtidos de 40 cadelas submetidas à ovário-salpingo-histerectomia (OSH) eletiva. Após a OSH, os ovários foram imediatamente transportados a uma temperatura de 4 ºC. No laboratório, os ovários foram seccionados em fatias finas ("slicing"), para a liberação dos complexos cumulus-oócito (COCs). Apenas os COCs grau 1 foram selecionados e colocados em meio de maturação por um período de 24, 48 e 72 h de maturação. Após o cultivo, os COCs foram colocados em placas contendo solução de hialuronidase 0.2% para a retirada completa das células do Cumulus. A atividade da proteína p34cdc2 foi detectada por ELISA. Com base nos resultados verifica-se que a atividade da proteína mostra-se tempo-dependente, atingindo o pico após 48h de MIV (p<0,01). Após 72h, a atividade demonstrou um decréscimo. Com base neste estudo pode-se concluir que a proteína quinase p34cdc2 desempenha uma função de suma importância na progressão da meiose em cadelas. Dessa forma, a compreensão melhor dessa proteína assim como de outra que participam do processo de maturação poderá contribuir para o estabelecimento de meios mais adequados que melhorem significativamente as taxas dematuração.

The control of the cell cycle is regulated by a cascade of coordinated events that can act by influencing the expression or repression of the activity of proteins related to meiosis resumption. Studies have indicated that the activity of these proteins is time-dependent in the in vitro maturation process (IVM). This work aimed to evaluate the kinetics of the p34cdc2 kinase activity during IVM of canine oocytes. Ovaries were obtained from 40 bitches submitted to elective ovary-salpingo-hysterectomy (OSH). After OSH, ovaries were immediately transported at temperature of 4 °C. In the laboratory, ovaries were sliced for the release of cumulus-oocyte complexes (COCs). Only grade 1 COCs were selected and placed in maturation medium for a period of 24, 48 and 72 h of maturation. After culturing, COCs were plated of 0.2% hyaluronidase solution for complete removal of cumulus cells. The activity of the p34cdc2 protein was detected by ELISA. Based on the results, it was observed that the activity of the protein is time-dependent, peaking after 48 hours of IVM (p 0.01). After 72 hours, activity declined. Based on this study, it could be concluded that the p34cdc2 protein kinase plays a very important role in the meiosis progression in bitches. Thus, a better understanding of this protein as well as of others that participate in the maturation process may contribute to the establishment of more adequate media to significantly improve maturation rates.

Avaliação da atividade da proteína quinase P34Cdc2 na maturação in vitro de oócitos caninos / Evaluation of p34cdc2 kinase activity in the in vitro maturation of canine oocytes

O controle do ciclo celular é regulado por uma cascata de eventos coordenados que podem atuar influenciando na expressão ou repressão da atividade de proteínas relacionadas a retomada da meiose. Estudos indicam que a atividade dessas proteínas mostra-se tempo-dependente no processo de maturação in vitro (MIV). Esse trabalho teve o objetivo de avaliar a cinética da atividade quinase p34cdc2 durante a MIV de oócitos caninos. Ciência Animal 27(1), 2017. Os ovários foram obtidos de 40 cadelas submetidas à ovário-salpingo-histerectomia (OSH) eletiva. Após a OSH, os ovários foram imediatamente transportados a uma temperatura de 4 ºC. No laboratório, os ovários foram seccionados em fatias finas ("slicing"), para a liberação dos complexos cumulus-oócito (COCs). Apenas os COCs grau 1 foram selecionados e colocados em meio de maturação por um período de 24, 48 e 72 h de maturação. Após o cultivo, os COCs foram colocados em placas contendo solução de hialuronidase 0.2% para a retirada completa das células do Cumulus. A atividade da proteína p34cdc2 foi detectada por ELISA. Com base nos resultados verifica-se que a atividade da proteína mostra-se tempo-dependente, atingindo o pico após 48h de MIV (p<0,01). Após 72h, a atividade demonstrou um decréscimo. Com base neste estudo pode-se concluir que a proteína quinase p34cdc2 desempenha uma função de suma importância na progressão da meiose em cadelas. Dessa forma, a compreensão melhor dessa proteína assim como de outra que participam do processo de maturação poderá contribuir para o estabelecimento de meios mais adequados que melhorem significativamente as taxas dematuração.(AU)

The control of the cell cycle is regulated by a cascade of coordinated events that can act by influencing the expression or repression of the activity of proteins related to meiosis resumption. Studies have indicated that the activity of these proteins is time-dependent in the in vitro maturation process (IVM). This work aimed to evaluate the kinetics of the p34cdc2 kinase activity during IVM of canine oocytes. Ovaries were obtained from 40 bitches submitted to elective ovary-salpingo-hysterectomy (OSH). After OSH, ovaries were immediately transported at temperature of 4 °C. In the laboratory, ovaries were sliced for the release of cumulus-oocyte complexes (COCs). Only grade 1 COCs were selected and placed in maturation medium for a period of 24, 48 and 72 h of maturation. After culturing, COCs were plated of 0.2% hyaluronidase solution for complete removal of cumulus cells. The activity of the p34cdc2 protein was detected by ELISA. Based on the results, it was observed that the activity of the protein is time-dependent, peaking after 48 hours of IVM (p 0.01). After 72 hours, activity declined. Based on this study, it could be concluded that the p34cdc2 protein kinase plays a very important role in the meiosis progression in bitches. Thus, a better understanding of this protein as well as of others that participate in the maturation process may contribute to the establishment of more adequate media to significantly improve maturation rates.(AU)

Cloning, structural modelling and characterization of VesT2s, a wasp venom hyaluronidase (HAase) from Vespa tropica

Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (4297 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (/)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.(AU)

Cloning, structural modelling and characterization of VesT2s, a wasp venom hyaluronidase (HAase) from Vespa tropica

Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (4297 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (/)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.

Cloning, structural modelling and characterization of VesT2s, a wasp venom hyaluronidase (HAase) from Vespa tropica

Background: Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (42-97 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (α/β)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.(AU)

Comparison of phenotypic and genotypic identification methods of Pasteurella multocida serotypes isolated from pigs

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...](AU)

Comparison of phenotypic and genotypic identification methods of Pasteurella multocida serotypes isolated from pigs

Background: Pasteurella multocida serotypes A and D are commonly associated with pneumonia and pleuritis in pigs. Different phenotypic techniques, such as hyaluronidase and acriflavine tests, and genotyping techniques, such as PCR, are used to distinguish between these serotypes. The objective of this study was to compare the capsular identification methods of type A and type D P. multocida isolated from pigs using both phenotypic (hyaluronidase and acriflavine tests) and genotypic (multiplex PCR) techniques. Materials, Methods & Results: A total of 44 lyophilized P. multocida isolates, obtained between 1981 and 1997 from pig farms at Rio Grande do Sul State, Brazil, were analyzed. The isolates were reactivated in Brain Heart Infusion (BHI) broth and cultured in BHI broth and blood agar supplemented with 5% sheep blood. Colony identity was further confirmed by evaluating colony morphology in blood agar and confirming the absence of growth on MacConkey agar. Bacteria in Tryptone Soy Agar (TSA) were used for the Triple Sugar Iron (TSI), Sulfide-Indole-Motility (SIM), and nitrate, glucose, lactose, sucrose and mannitol fermentation tests. For hyaluronidase test, P. multocida colonies were streaked transversally across the entire plate, approximately 3-5mm apart, in order to observe their lines of growth. Following this, a hyaluronidase producing strain of Staphylococcus aureus[...]