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1.
Vet J ; 254: 105396, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31836164

RESUMO

Despite the increasing availability of feline blood, which is collected and stored for transfusion purposes, few studies have assessed the effect of storage on feline whole blood (WB) units. The purpose of this study was to investigate selected hematologic and biochemical changes during storage of feline WB units and to determine when they occurred. Data from a quality control program for WB units was used in this study. Twelve feline WB units, collected using an open system, were sampled every 7 days from the point of collection to the end of storage at 35 days (D0, D7, D14, D21, D28, and D35). Measurements at each time point were: (1) hematologic parameters; (2) percentage hemolysis; (3) morphologic index scored at 0-3, based on echinocyte transformation of the erythrocytes; and (4) selected biochemical parameters. Aerobic and anaerobic culture was performed at D0 and D35. Results were compared statistically to D0 (statistical significance set at <0.01). Storage did not result in statistically significant changes in measured hematological parameters. There were statistically significant increases in percentage hemolysis and morphologic index, starting from D21 (P=0.000 and P=0.004, respectively). Glucose decreased significantly from D21 (P=0.003); potassium increased significantly from D7 (P=0.001); and sodium increased significantly, starting from D28 (P=0.009). Bacteria were not isolated. Blood in feline WB units collected using an open system underwent some significant storage changes that were time-dependent. As these changes could affect the quality and the utility of stored WB used in feline transfusion medicine, further study is required to determine their clinical importance.


Assuntos
Preservação de Sangue/veterinária , Coleta de Amostras Sanguíneas/veterinária , Gatos/sangue , Animais , Sangue/microbiologia , Glicemia/metabolismo , Forma Celular , Testes Hematológicos/veterinária , Hemólise , Potássio/sangue
2.
Food Chem ; 249: 22-29, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29407927

RESUMO

This study was designated to ascertain the effectiveness of polylactic acid (PLA) based packaging solution to store red fresh meat during its refrigerated shelf-life. Recently the attention in the packaging industry regarding the use of bioplastics has been shifting from compostable/biodegradable materials toward biobased materials. Steaks obtained from semimembranous muscle of Piemontese beef were packaged in PLA trays closed with a lid made of PLA film and for comparison purposed in a conventional reference package consisting of a amorphous polyethylene terephthalate/polyethylene (APET/PET) trays and wrapped in plastic film of polyvinyl chloride (PVC). The packaging under modified atmosphere MAP was carried out by using a gas mixture of 66% O2, 25% CO2 and 9%N2. By using PLA packaging combination it was possible to maintain an optimum red colour together with a reduced content of volatile compounds associated to off-flavours of meat samples particularly related to the oxidation phenomena.


Assuntos
Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Carne Vermelha , Animais , Materiais Biocompatíveis , Bovinos , Cor , Qualidade dos Alimentos , Projetos Piloto , Poliésteres/química , Polietileno , Cloreto de Polivinila , Carne Vermelha/microbiologia
3.
Vet J ; 206(3): 423-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26526525

RESUMO

Glucose, lactate and cortisol concentrations in amniotic fluid were measured at birth in 95 pups and related to neonatal viability based on Apgar scoring and to neonatal mortality. Neither amniotic parameters nor neonatal mortality were associated with the Apgar score. Stillborn pups showed high lactate (P < 0.001) and cortisol (P < 0.05) but low glucose amniotic concentrations (P < 0.001). No amniotic fluid differences were observed between normal and malformed pups. Amniotic glucose (P < 0.001), lactate (P < 0.05) and cortisol (P < 0.05) concentrations were higher in pups delivered by vaginal parturition than by Caesarean section. Birth weight was higher in live pups than in pups dying within 48 h (P < 0.05). Although these are preliminary results, the analysis of amniotic fluid collected at birth could be a valuable predictor of neonatal outcomes in dogs.


Assuntos
Líquido Amniótico/metabolismo , Animais Recém-Nascidos , Cães , Resultado da Gravidez/veterinária , Prenhez , Animais , Feminino , Humanos , Mortalidade , Gravidez , Prognóstico
4.
Dis Markers ; 2015: 387825, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25960592

RESUMO

Neutrophil gelatinase-associated lipocalin (NGAL) is a neutrophil-derived protein whose concentration increases in plasma and urine with ongoing renal damage. Urinary leucocytes can be a potential source of urinary NGAL. The aim of this study is to investigate the effects of urinary neutrophil count and other urinary parameters on urinary NGAL values in urine with negative culture. Urinalysis, urine culture, and determination of urinary NGAL were performed on 33 clinically healthy nonproteinuric dogs with negative urinoculture. The median uNGAL concentration in dogs in this study population was 9.74 ng/mL (IQR 1.93-25.43 ng/mL). In samples with WBCs > 5 hpf (mean 15.9, 6-50 leucocytes/hpf), median uNGAL value was significantly higher than that in samples with WBCs < 5 hpf (mean 0.9, 0-3 leucocytes/hpf), (4.96 pg/mL (0.29-11.34) and 23.65 pg/mL (20.04-29.80), resp.; P = 0.0053). The severity of urinary pyuria and the UPC value were correlated with uNGAL concentration. The results of our study show that urinary NGAL concentration is correlated with WBCs number in urinary sediment of dogs with negative urinoculture. The present study suggests that noninfectious pyuria is significantly correlated with urinary NGAL values and might influence uNGAL values.


Assuntos
Proteínas de Fase Aguda/urina , Lipocalinas/urina , Proteínas Proto-Oncogênicas/urina , Piúria/veterinária , Animais , Biomarcadores/urina , Estudos de Casos e Controles , Cães
5.
Theriogenology ; 77(8): 1549-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22289216

RESUMO

The study of canine vaginal cytology underwent limited evolution over the years. Presence and significance of inflammatory cells in vaginal smears are little considered aspects in the bitch. Moreover, occurrence of vaginal bacteria in breeding bitches during follicular phase of the reproductive cycle, in absence of clinical signs of infection, involves the difficult question of antibiotics administration. The aim of this study was to relate findings in vaginal cytology (presence of neutrophils, lymphocytes, eosinophils, erytrocytes and bacteria) and microbial environment during proestrus with fertility outcomes (development of pregnancy, uterine infection, resorption, abortion and neonatal mortality). Bacteria sensitivity to antibiotics normally used in small animal practice was also evaluated. Bacteria isolated from vagina, in order of frequency, were Enterococcus faecalis, Streptococcus ß-haemolyticus, Pasteurella multocida, E. coli, Klebsiella pneumoniae, Proteus mirabilis, E. coli haemolyticus, Arcanobacterium pyogenes, Streptococcus spp., Staphylococcus spp. and Acinetobacter spp. No mycoplasmas were observed. The present study showed that proestrous cytological aspects do not affect fertility. Eosinophils were never detected, while erythrocytes were always detected. During diestrus, E. coli was found in all pregnant bitches that developed clinical symptoms of uterine disorders (n = 3), resulting in uterine infection, resorption or abortion, but without statistical significance. Vaginal presence of Streptococcus spp. in proestrus was instead negatively associated with development of uterine infections (P = 0.005). Therefore, Streptococcus spp. could have a protective competitive role against more dangerous pathogens affecting fertility of the bitch. Among the 12 antibiotics tested, Gram-negative bacteria showed a significant sensitivity towards the amoxicillin and clavulanic acid association (P = 0.038). However, antibiotic treatment before mating, on the basis of positive culture, yet in the absence of clinical signs, seems to be unnecessary besides harmful leading to imbalance in vaginal commensal flora with adverse effects on fertility. In conclusion, vaginal bacteria, neutrophils, lymphocytes and erytrocytes should be considered as physiological aspect in the bitch during proestrus that does not require antibiotic therapy when asymptomatic.


Assuntos
Cães/microbiologia , Fertilidade , Proestro/fisiologia , Vagina/microbiologia , Animais , Diestro/fisiologia , Feminino , Leucócitos/citologia , Linfócitos/citologia , Vagina/citologia , Esfregaço Vaginal/veterinária
6.
Br Poult Sci ; 51(1): 152-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20390581

RESUMO

1. The effect of drinking water supplementation with lycopene on the semen quality, fertility and immunity of broiler breeders was evaluated. 2. Broiler breeder males were individually caged from 25 to 42 weeks old and divided into two group: L group, treated birds (lycopene 0.5 g/l) and C group, control birds. Laying hens were divided into two groups and artificially inseminated. 3. Semen variables were evaluated and daily fertility recorded. Serum bactericidal activity was tested. 4. Semen production and viability were affected by lycopene supplementation. Serum bactericidal activity was better in L than in C group. The fertility rate curve of the L group displayed a positive trend.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Galinhas/imunologia , Fertilidade/imunologia , Sêmen/imunologia , Animais , Feminino , Licopeno , Masculino , Distribuição Aleatória , Motilidade dos Espermatozoides/imunologia
7.
Theriogenology ; 72(8): 1032-40, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19748663

RESUMO

Information regarding the plasma hormone profiles of prostaglandins (PGs), cortisol (C), and progesterone (P4) during pathologic processes in newborn foals is scarce. The aim of this study was to determine the plasma concentrations of these hormones in diseased foals (n=40) and healthy at-term foals (n=24) (Equus caballus) during the first 2 weeks of life. Blood samples were collected daily, before any treatment with nonsteroidal drugs in diseased foals, and plasma was analyzed by radioimmunoassay. 15-Ketodihydro-PGF(2alpha) (PGM) was consistently higher in diseased foals than in healthy foals, probably related to roles of PGs in completing organ maturation and/or the presence of oxidative stress or inflammation. Similar trends were observed for C and P4. In diseased newborns, only PGM was significantly higher in nonsurviving foals, although C showed a similar profile. When specific diseases were considered, the levels of PGM and C were lower in premature foals at 12h of life, whereas the concentration of P4 was higher than in controls. The results of this study demonstrate the differences in plasma hormone levels between healthy and pathologic newborn foals, particularly during the first 2 d of life, probably reflecting the inability of diseased foals to cope with the transition between fetal and neonatal life.


Assuntos
Animais Recém-Nascidos/sangue , Dinoprosta/análogos & derivados , Doenças dos Cavalos/sangue , Cavalos/sangue , Hidrocortisona/sangue , Progesterona/sangue , Animais , Dinoprosta/sangue , Estresse Oxidativo , Fatores de Tempo
11.
Avian Dis ; 45(1): 257-61, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11332492

RESUMO

Beginning at the end of March 1999, a syndrome characterized by severe depression, anorexia, fever, and respiratory and enteric symptoms appeared in flocks of turkeys and, to a lesser extent, of chickens in the densely populated poultry-rearing regions of northeast Italy. The disease was characterized by sinusitis, tracheitis, peritonitis, and pancreatitis. The mortality varied between 5% and 90%. The disease was diagnosed as low pathogenic avian influenza, H7N1 serotype. After a summer period of declining cases, the disease reappeared in autumn exclusively in turkeys. Since the middle of December 1999, many farms of chickens, turkeys, and guinea fowl were abruptly affected by a highly pathogenic H7N1 virus, with very severe depression and mortality up to 100% in a few days. By the end of March 2000, nearly 500 farms, representing over 15 million birds, were affected or depopulated. To date, control measures have focused on improved biosecurity measures. Vaccine was not allowed, but its use was debated.


Assuntos
Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Animais , Galinhas , Vírus da Influenza A , Itália/epidemiologia , Pancreatite/complicações , Pancreatite/veterinária , Peritonite/complicações , Peritonite/veterinária , Sorotipagem , Sinusite/complicações , Sinusite/veterinária , Traqueíte/complicações , Traqueíte/veterinária , Perus
12.
Avian Pathol ; 29(4): 311-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19184820

RESUMO

Three very severe episodes of Escherichia coli infection in hens from the same farm, at the beginning of laying, are reported. They were characterized by no clinical signs, but sudden mortality, from 5 to 10%, with severe lesions of septicaemia and fibrinous polyserositis. A Gram-negative bacterium was consistently isolated in pure culture from tissues. Isolates were typed biochemically as E. coli, but they were lactose negative and non-motile. The serotyping tests typed the isolates as somatic group O111. The isolates were sensitive to enrofloxacin, amoxycil and colimycin, and partially sensitive to flumequine, all of which were used for therapy. The disease was reproduced experimentally in both specific pathogen free chickens and commercial layers by intramuscular inoculation of the E. coli, but only in some layers when inoculated by the oro-nasal route. The stress of the onset of lay seemed to be the most probable precipitating cause of the disease.

13.
Avian Pathol ; 27(6): 591-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18484048

RESUMO

The results of in vitro tests for induction of antibiotic resistance in some strains of Mycoplasma gallisepticum are reported. The number of passages required to induce resistance varied considerably between different antibiotics. In two groups of tests, with different strains of M. gallisepticum, resistance (>/= 1 mg/ml) to streptomycin appeared after two to three passages, to erythromycin and spiramycin after five to eight passages, to tylosin after nine to eleven and to enrofloxacin after eight to ten passages. With chlortetracycline the increase in resistance was very low (no more than ten times the starting minimal inhibitory concentration). Cross-sensitivity tests using strains with induced resistance to the different antibiotics demonstrated that those which were resistant to tylosin were also resistant to other macrolides ( > 1 mg/ml), whereas strains made resistant to erythromycin and spiramycin appeared only less sensitive (2 to 200 mug/ml) to tylosin in comparison with the original strains. Streptomycin, chlortetracycline and enrofloxacin induced very little or no cross-resistance.

14.
Protein Sci ; 3(8): 1296-304, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7527260

RESUMO

The amino acid sequence of mouse liver NAD(P)H:quinone acceptor oxidoreductase (EC 1.6.99.2) has been determined by tandem mass spectrometry and deduced from the nucleotide sequence of the cDNA encoding for the enzyme. The electrospray mass spectral analyses revealed, as previously reported (Prochaska HJ, Talalay P, 1986, J Biol Chem 261:1372-1378), that the 2 forms--the hydrophilic and hydrophobic forms--of the mouse liver quinone reductase have the same molecular weight. No amino acid sequence differences were found by tandem mass spectral analyses of tryptic peptides of the 2 forms. Moreover, the amino-termini of the mouse enzymes are acetylated as determined by tandem mass spectrometry. Further, only 1 cDNA species encoding for the quinone reductase was found. These results suggest that the 2 forms of the mouse quinone reductase have the same primary sequences, and that any difference between the 2 forms may be attributed to a labile posttranslational modification. Analysis of the mouse quinone reductase cDNA revealed that the enzyme is 273 amino acids long and has a sequence homologous to those of rat and human quinone reductases. In this study, the mouse quinone reductase cDNA was also ligated into a prokaryotic expression plasmid pKK233.2, and the constructed plasmid was used to transform Escherichia coli strain JM109. The E. coli-expressed mouse quinone reductase was purified and characterized. Although mouse quinone reductase has an amino acid sequence similar to those of the rat and human enzymes, the mouse enzyme has a higher NAD(P)H-menadione reductase activity and is less sensitive to flavones and dicoumarol, 2 known inhibitors of the enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Clonagem Molecular , Escherichia coli/genética , Expressão Gênica , NAD(P)H Desidrogenase (Quinona)/química , NAD(P)H Desidrogenase (Quinona)/genética , NADPH Desidrogenase , Análise de Sequência , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromatografia Líquida de Alta Pressão , DNA Complementar/química , DNA Complementar/genética , Dicumarol/farmacologia , Eletroforese em Gel de Poliacrilamida , Fígado/enzimologia , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Proteínas Recombinantes/metabolismo
15.
Biochem J ; 284 ( Pt 3): 855-60, 1992 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-1622401

RESUMO

A prokaryotic expression plasmid, pKK-DT2, containing the cDNA of rat liver NAD(P)H:quinone-acceptor oxidoreductase (EC 1.6.99.2; DT-diaphorase) was constructed and used to transform Escherichia coli strain JM109. The rat liver quinone reductase was expressed in strain in JM109 and was inducible with isopropyl beta-D-thiogalactopyranoside (IPTG). The expressed rat protein was purified by affinity chromatography and had kinetic and physical properties identical with the protein purified from rat liver in that it could utilize either NADH or NADPH as the electron donor and its activity was inhibited by dicoumarol. In addition, we have generated four mutants, Arg-177----His (R177H), Arg-177----Ala (R177A), Arg-177----Cys (R177C) and Arg-177----Leu (R177L), using this expression system. Several of the mutants behaved anomalously on SDS/PAGE, but all of the mutant proteins had the expected M(r) as determined by electrospray m.s. These results and those obtained from enzyme kinetic analysis, u.v./visible absorption spectral analysis, and flavin and tryptophan fluorescence analysis of the wild-type enzyme and four mutants indicated that mutations at Arg-177 changed the conformation of the enzyme, resulting in a decrease in enzyme activity. Replacing Arg-177 with leucine altered the protein conformation and decreased FAD incorporation.


Assuntos
Arginina , Fígado/enzimologia , Mutagênese Sítio-Dirigida , NAD(P)H Desidrogenase (Quinona)/genética , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Cinética , Dados de Sequência Molecular , Peso Molecular , NAD(P)H Desidrogenase (Quinona)/isolamento & purificação , NAD(P)H Desidrogenase (Quinona)/metabolismo , Plasmídeos , Ratos , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição
16.
J Am Soc Mass Spectrom ; 3(4): 311-7, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-24243041

RESUMO

A shock wave model is proposed to explain certain features of recently reported spectra obtained by massive duster impact (MCI) mass spectrometry. It is suggested that clusters that impact glycerol matrices with energies/nucleon in the range 0.01 eV/u < E/N < 1.0 eV/u provide an extremely soft method for sputtering intact biomolecules, Compared to the high energy/nucleon characteristic of atomic or molecular ion primary beams (typically < 50 eV/u), massive cluster primary beams possess much lower energies/nucleon, which are insufficient to cause appreciable ionization and radiation damage of matrix material. Moreover, fragmentation products of parent molecular ions are effectively lower. With these benefits, MCI spectra show lower chemical noise background and enhanced signalto-noise ratios. Rankine-Hugoniot analysis of the shock conditions is used to arrive at an estimate of the heat retained in the collision-affected matrix volume after bombardment by a characteristic cluster. For a cluster collision resulting in a 26.8 GPa shock pressure, by analogy with water data, rapid heating of the shocked volume to 1000 °C or more is plausible. In a beam consisting of clusters distributed in size and charge, an estimate is made for the range of cluster sizes over which hyrodynamic shock wave theory applies.

17.
Rapid Commun Mass Spectrom ; 5(10): 441-5, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1841643

RESUMO

A new ion desorption method is described that utilizes a primary beam of massive, multiply charged cluster ions to generate secondary ions of peptides in a glycerol matrix. The massive cluster ion beam is generated via electrohydrodynamic emission using a 1.5 M solution of ammonium acetate in 30% aqueous glycerol. Negative ion spectra of peptides obtained using this technique show greatly decreased relative intensities for fragment ions and 'chemical noise' background when compared to spectra obtained using a xenon atom primary beam. The near absence of fragments derived from radiation damage to the sample solution is attributed to the impact of primary particles with energies less than 1 eV/nucleon.


Assuntos
Peptídeos/análise , Sequência de Aminoácidos , Eletroquímica , Espectrometria de Massas , Dados de Sequência Molecular
18.
J Biol Chem ; 265(32): 19728-35, 1990 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1700979

RESUMO

Bovine myelin basic protein (MBP) was found to be an excellent in vitro substrate (apparent Km = 50 microM) for MAP (mitogen-activated protein) kinase and can be used in lieu of microtubule-associated protein 2 for purification and functional studies of the enzyme. MBP phosphotransferase activity co-purified with MAP kinase during sequential DE52, phenyl-Superose, and gel filtration chromatography, and kinase activities for the two substrates were co-regulated by mitogen stimulation. MAP kinase phosphorylated MBP exclusively on threonine, and only one major phosphopeptide was generated by digestion with trypsin or endoproteinase Lys-C. Using mass spectrometry, we determined that the phosphorylation site is threonine 97, present in the conserved triproline loop of MBP, with (partial) sequence -Thr-Pro-Arg-Thr97-Pro-Pro-Pro-. Thr97 is a known in vivo phosphorylation site in MBP although enzymes capable of phosphorylating this site have not been identified previously. MAP kinase phosphorylated peptide 88-109 from rabbit MBP and a synthetic peptide 91-109 from human MBP but did not phosphorylate either the histone H1 peptide, utilized by p34cdc2, or the peptide substrate for the recently described proline-directed kinase. Thus, the sequence surrounding threonine 97 in bovine MBP may contain essential features of a recognition sequence for MAP kinase.


Assuntos
Proteína Básica da Mielina/metabolismo , Fosfotreonina/metabolismo , Proteínas Quinases/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Ativação Enzimática , Espectrometria de Massas , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Dados de Sequência Molecular , Proteína Básica da Mielina/química , Mapeamento de Peptídeos , Fosforilação , Fosfotreonina/análise , Proteínas Quinases/isolamento & purificação , Especificidade por Substrato
19.
Biochim Biophys Acta ; 1040(2): 217-24, 1990 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-2400773

RESUMO

The B-chain of the acidic subunit of crotoxin proved refractory to Edman degradation. When subjected to sequence analysis using tandem mass spectrometry, pyroglutamate was found at the amino-terminal end, even though earlier attempts to de-block with pyroglutamate aminopeptidase were unsuccessful. The B-chain contained 35 amino acids and showed 91% amino acid identity with the corresponding segment from Mojave toxin, a homologous neurotoxin from Crotalus scutulatus scutulatus. The sequence of the last 24 residues of the B-chain is consistent with that previously published (Aird, S.D., Kaiser, I.I., Lewis, R.V. and Kruggel, W.G. (1985) Biochemistry 24, 7054-7058), except at position 20, where Edman degradation gave glycine and mass spectrometry gave glutamic acid.


Assuntos
Venenos de Crotalídeos , Crotoxina , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Análise de Fourier , Substâncias Macromoleculares , Espectrometria de Massas , Dados de Sequência Molecular , Fragmentos de Peptídeos/isolamento & purificação , Fosfolipases A , Homologia de Sequência do Ácido Nucleico , Serpentes
20.
Biochim Biophys Acta ; 1037(3): 413-21, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2310754

RESUMO

Mojave toxin, a heterodimeric, neurotoxic phospholipase complex from Crotalus scutulatus scutulatus, is one of a group of closely related rattlesnake toxins for which much structural information is still lacking. The complete amino-acid sequence of the acidic subunit from Mojave toxin was determined. The three individual peptide chains, derived from the acidic subunit by reductive alkylation, were separated by high-performance liquid chromatography. Fragmentations of the A and B chains were done using specific proteinases and the resulting peptide mixtures were fractionated by reverse-phase high-performance liquid chromatography. Sequence analyses on the intact chains and the fragments from digests were done by automated Edman degradation, carboxypeptidase Y degradation and triple-quadrupole and tandem-quadrupole Fourier-transform mass spectrometry. The sequence for each acidic subunit chain is very similar to the corresponding chain from the related neurotoxin complex, crotoxin, and overall the sequence is similar to the sequences of group I and II phospholipases A2. The N-terminus of the B chain is blocked by pyroglutamic acid. The existence of two distinct and closely related C chains was established. It is unlikely that the small sequence difference can account for the isoforms that are present in purified Mojave toxin and in unfractionated venom.


Assuntos
Venenos de Crotalídeos , Neurotoxinas , Sequência de Aminoácidos , Carboxipeptidases , Cromatografia Líquida de Alta Pressão , Crotoxina , Concentração de Íons de Hidrogênio , Cinética , Espectrometria de Massas , Dados de Sequência Molecular , Fragmentos de Peptídeos , Fosfolipases A
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