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1.
Diabetes Obes Metab ; 11(3): 223-33, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18564175

RESUMO

AIM: Vasopeptidase inhibitors are drugs that inhibit angiotensin-converting enzyme and neutral endopeptidase (NEP). The latter is a protease that degrades vasoactive peptides and is increased in diabetes. We have previously shown that treating streptozotocin-induced diabetic rats, an animal model of type 1 diabetes, with AVE7688, a vasopeptidase inhibitor, improves neurovascular and neural function. In this study, we determined the effect of treating Zucker diabetic fatty (ZDF) rats, an animal model of type 2 diabetes, with AVE7688 on vascular and neural function. METHODS: ZDF rats at 12 weeks of age were treated for 12 weeks with AVE7688 (500 mg/kg diet). Afterwards, vascular reactivity of epineurial arterioles of the sciatic nerve and nerve conduction velocity and blood flow was determined. RESULTS: Vascular and neural function was significantly impaired in ZDF rats compared with age-matched lean (control) rats. Treating ZDF rats with AVE7688 improved vascular relaxation to acetylcholine and calcitonin gene-related peptide in epineurial arterioles. Motor and sensory nerve conduction velocity, endoneurial blood flow and thermal nociception end-points were also improved by treatment compared with untreated ZDF rats. Superoxide and expression of NEP were increased in epineurial arterioles from ZDF rats and attenuated by treatment with AVE7688. CONCLUSIONS: AVE7688 is an effective treatment for microvascular and neural disease in ZDF rats. Thus, vasopeptidase inhibitors may be an effective treatment for diabetic microvascular and neural complication in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Hipoglicemiantes/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Masculino , Neprilisina/antagonistas & inibidores , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Ratos , Ratos Zucker , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiopatologia
2.
Diabetes Obes Metab ; 10(1): 64-74, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17970755

RESUMO

AIM: We had previously demonstrated that vascular and neural dysfunction in Zucker diabetic fatty (ZDF) rats is progressive. In this study, we sought to determine whether monotherapy of ZDF rats can reverse the vascular and nerve defects. METHODS: ZDF rats at 16 weeks of age were treated for 12 weeks with the angiotensin-converting enzyme inhibitor enalapril, the antioxidant alpha-lipoic acid, the HMG-CoA reductase inhibitor rosuvastatin or the PPARgamma agonist rosiglitazone. Vasodilation of epineurial arterioles was measured by videomicroscopy. Endoneurial blood flow (EBF) was measured by hydrogen clearance, and nerve conduction velocity was measured following electrical stimulation of motor or sensory nerves. RESULTS: Motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV) (70 and 77% of control, respectively), EBF (64% of control), and vascular relaxation in response to acetylcholine (50% of control) and calcitonin gene-related peptide (CGRP; 73% of control) are impaired in ZDF rats at 28 weeks of age compared with lean littermate controls. Treatment with enalapril and alpha-lipoic acid attenuated the decrease in MNCV and SNCV. Enalapril, alpha-lipoic acid and rosiglitazone treatment of ZDF rats were partially effective in improving endothelium-dependent vascular dysfunction as measured by vascular relaxation in response to acetylcholine. The same drugs also attenuated the decrease in EBF. However, impairment in vascular relaxation in response to CGRP was improved with only alpha-lipoic acid or rosuvastatin treatment. The increase in superoxide and nitrotyrosine levels in vascular tissue was attenuated by all treatments. CONCLUSIONS: The efficacy of monotherapy treatment of ZDF rats using different classes of drugs for vascular and neural dysfunction once complications have developed did not achieve expected levels. This could be because of the complex aetiology of vascular and neural disease in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Angiopatias Diabéticas/etiologia , Neuropatias Diabéticas/etiologia , Condução Nervosa , Obesidade/fisiopatologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/metabolismo , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/metabolismo , Masculino , Neurônios Motores/fisiologia , Ratos , Ratos Zucker , Resultado do Tratamento
3.
Biochim Biophys Acta ; 1383(1): 55-62, 1998 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-9546046

RESUMO

The primary structures of isomyoglobins MbI and MbII from the body wall musculature of the polychaete Arenicola marina were investigated, aiming to trace the molecular basis for their functional differentiation. Unexpectedly, five chains, MbIa, MbIb, MbIIa, MbIIb and MbIIc, each consisting of 145 amino-acid residues and occurring in a ratio of = 33:17:25:12.5:12.5 were found. All substitutions can be explained by one-point mutations. With the exception of the 41(C6)Asn-->Asp(MbI/MbII) exchange that appears to be the basis for the electrophoretic separation of MbI and MbII, the substitutions do not involve drastic changes in the character of the side-chains. Pairwise comparison of MbIa and MbIIa with other invertebrate globin chains indicate the following sequence of decreasing identities: Aplysia (mollusc) Mb, Chironomus (insect) CTT III hemoglobin, whale Mb and Ascaris (nematode) Mb. The marked difference in O2 affinities between MbI and MbII appears attributable to 62Pro which distorts the E helix around E6 and occurs in all MbII chains, but in only 33% of the MbI chains (MbIb).


Assuntos
Mioglobina/química , Poliquetos/química , Sequência de Aminoácidos , Animais , Aplysia , Dados de Sequência Molecular , Mutação Puntual , Estrutura Secundária de Proteína , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Baleias
4.
FEBS Lett ; 161(2): 225-9, 1983 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-6617875

RESUMO

The amino acid sequence of the N-terminal region of the two basic bovine beta-crystallin B1 chains has been analyzed. The results reveal that beta B1b is derived in vivo from the primary gene product beta B1a by removal of a short N-terminal sequence. It appears that the beta B1 chains have the same domain structure as observed in other beta- and gamma-crystallin chains. They have, however, a very long N-terminal extension in comparison with other beta-chains. This extension is mainly composed of a remarkable Pro- and Ala-rich sequence, which suggests an interaction of these structural proteins with the cytoskeleton and/or the plasma membranes of the lens cells.


Assuntos
Alanina/isolamento & purificação , Cristalinas , Prolina/isolamento & purificação , Sequência de Aminoácidos , Animais , Bovinos , Fenômenos Químicos , Química , Fragmentos de Peptídeos
5.
Methods Inf Med ; 53(2): 73-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24549290

RESUMO

INTRODUCTION: This article is part of a Focus Theme of METHODS of Information in Medicine on Health Record Banking. BACKGROUND: Poor communication of health care information between health care providers (HCP) is still a major problem. One recent approach is the concept of Health Record Banking. OBJECTIVES: With this report we want to introduce the Lower Saxony Bank of Health (LSBH) to the international community. The main objective of this paper is to report and explain: 1) why this organization has been founded, 2) which basic principles have been set, 3) which services will be provided, 4) which type of organization has been chosen, and 5) which architectural framework has been selected. METHODS: To report and discuss how we plan to achieve the intended objectives. RESULTS: The LSBH was founded as an entrepreneurial company, regarding itself as a neutral third-party information broker. The bank does not store medical documents on its central servers but offers a document registry with links to documents stored at participating health care providers. Subject to valid patient consent, the LSBH grants access to these documents to authorized health care providers. To implement our services, we chose the established technical frameworks of the Integrating the Healthcare Enterprise (IHE) initiative using cross-enterprise document sharing (XDS). CONCLUSIONS: Different approaches to establish health information exchange (HIE) are in early stages and some have failed in the past. Health Record Banking can address major challenges described in the literature about HIE. The future will show if our provider-sponsored business model is sustainable. After reaching a stable network, we intend to add additional HCPs, e.g., care homes or ambulance services, to the network.


Assuntos
Sistemas Computacionais , Bases de Dados como Assunto , Registros Eletrônicos de Saúde/organização & administração , Troca de Informação em Saúde , Registro Médico Coordenado , Sistemas Computadorizados de Registros Médicos/organização & administração , Modelos Organizacionais , Alemanha , Humanos , Objetivos Organizacionais
6.
Methods Inf Med ; 51(3): 199-209, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21915435

RESUMO

BACKGROUND: Health care network eHealth.Braunschweig has been started in the South-East region of Lower Saxony in Germany in 2009. It composes major health care players, participants from research institutions and important local industry partners. OBJECTIVES: The objective of this paper is firstly to describe the relevant regional characteristics and distinctions of the eHealth.Braunschweig health care network and to inform about the goals and structure of eHealth.Braunschweig; secondly to picture and discuss the main concepts and domain fields which are addressed in the health care network; and finally to discuss the architectural challenges of eHealth.Braunschweig regarding the addressed domain fields and defined requirements. METHODS: Based on respective literature and former conducted projects we discuss the project structure and goals of eHealth.Braunschweig, depict major domain fields and requirements gained in workshops with participants and discuss the architectural challenges as well as the architectural approach of eHealth.Braunschweig network. RESULTS: The regional healthcare network eHealth.Braunschweig has been established in April 2009. Since then the network has grown constantly and a sufficient progress in network activities has been achieved. The main domain fields have been specified in different workshops with network participants and an architectural realization approach for the transinstitutional information system architecture in the healthcare network has been developed. However, the effects on quality of information processing and quality of patient care have not been proved yet. Systematic evaluation studies have to be done in future in order to investigate the impact of information and communication technology on the quality of information processing and the quality of patient care. CONCLUSIONS: In general, the aspects described in this paper are expected to contribute to a systematic approach for the establishment of regional health care networks with lasting and sustainable effects on patient-centered health care in a regional context.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Informática Médica/organização & administração , Assistência Centrada no Paciente/organização & administração , Telemedicina/organização & administração , Sistemas Computacionais , Comportamento Cooperativo , Geografia , Alemanha , Humanos , Staphylococcus aureus Resistente à Meticilina , Avaliação de Programas e Projetos de Saúde , Sistema de Registros
7.
Rofo ; 182(10): 900-4, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20725878

RESUMO

During the last years most embolizations with the liquid agent Onyx have been performed in the field of neuroradiological interventions. There is minimal experience with arterial embolizations of the body trunk. 23 patients suffering from acute abdominal or thoracic bleeding underwent 28 embolizations with Onyx (17 male, 6 female, mean age 69 years). 27 interventions were technically and clinically successful. One patient with rebleeding from a jejunal artery aneurysm underwent surgery. Onyx embolizations were performed in renal, hepatic, iliac and bronchial arteries and esophageal varices. Compared with prior embolisation agents Onyx offers advantages due to good controllability. Fast arterial occlusion improves time management of patients. In comparison with prior techniques we observed a significant reduction of fluoroscopy time. Quantitative measurements demonstrated a significant higher embolisation agent contrast.


Assuntos
Dimetil Sulfóxido/uso terapêutico , Embolização Terapêutica/métodos , Hemoperitônio/terapia , Hemotórax/terapia , Polivinil/uso terapêutico , Idoso , Angiografia , Feminino , Seguimentos , Hemoperitônio/diagnóstico por imagem , Hemoperitônio/etiologia , Hemotórax/diagnóstico por imagem , Hemotórax/etiologia , Humanos , Masculino , Recidiva , Retratamento
9.
Hoppe Seylers Z Physiol Chem ; 361(6): 933-42, 1980.
Artigo em Alemão | MEDLINE | ID: mdl-7399413

RESUMO

The dimeric hemoglobin CTT VIIA (erythrocruorin) was isolated from the hemolymph of the larva from Chironomus thummi thummi and purified by preparative polyacrylamide gel electrophoresis. Peptides obtained by limited tryptical digestion were sequenced by automatic Edman degradation. For the elucidation of the sequence in the C-terminal region of the chain, additional cleavages with proteinase of Staphylococcus aureus and chymotrypsin were necessary. CTT VIIA is compared with human beta-chains and other hemoglobins of Chironomus. The amino acid residues in the pocket are especially discussed. Most of them are invariant in all Chironomus hemoglobins, independent of the size of the heme pocket, which is normal in some components and enlarged in others.


Assuntos
Dípteros/análise , Eritrocruorinas/análise , Hemoglobinas/análise , Sequência de Aminoácidos , Animais , Eletroforese em Gel de Poliacrilamida , Larva , Terminação Traducional da Cadeia Peptídica
10.
Z Naturforsch C Biosci ; 38(11-12): 1059-61, 1983.
Artigo em Alemão | MEDLINE | ID: mdl-6670355

RESUMO

The N-terminal sequence of porphobilinogen-synthase (EC 4.2.1.24) from bovine liver up to position 44 is given. After tryptic hydrolysis two N-terminal peptides with identical amino acid composition were isolated in the ratio 1:1. One peptide was blocked whereas the other one started with methionine and showed the same primary structure which had been estimated by automatic degradation of the enzyme. Four of the eight subunits of PBG-S have free methionine as N-terminal amino acid whereas the other half is blocked.


Assuntos
Terminação Traducional da Cadeia Peptídica , Sintase do Porfobilinogênio/análise , Sequência de Aminoácidos , Animais , Bovinos , Hidrólise , Fígado/enzimologia
11.
Biol Chem Hoppe Seyler ; 366(3): 245-56, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-4005041

RESUMO

Two activator proteins for sphingomyelin degradation were isolated from heat-treated extracts of human Gaucher spleen. The separation was based on the degree of affinity of the activators for ConA-Sepharose. Activator A1, which had affinity for ConA-Sepharose, was purified 1 430-fold, and activator A2, which had no affinity for ConA-Sepharose, 2 140-fold as compared with the original heat-treated extracts. The molecular masses of activator A1 and activator A2 were 6 000 and 3 500 Da, respectively, as determined by dodecyl sulfate electrophoresis, and approximately 5 000 Da as measured in the presence of 8M urea. The two activators had similar properties and a similar but not identical amino-acid composition. Both were shown to form a complex with sphingomyelin and stimulate the degradation of sphingomyelin by normal fibroblast homogenates and by an approximately 1 430-fold purified sphingomyelin phosphodiesterase ("acid sphingomyelinase") from normal human urine. This stimulation was greatly reduced after incubation with pronase E. The enzymic degradation of glucosylceramide and galactosylceramide was not affected by these activators.


Assuntos
Doença de Gaucher/metabolismo , Proteínas/análise , Esfingomielinas/metabolismo , Baço/análise , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Fibroblastos/metabolismo , Humanos , Hidrólise , Cinética , Peso Molecular , Ligação Proteica , Esfingomielina Fosfodiesterase/urina , Especificidade por Substrato , Fatores de Tempo
12.
Hoppe Seylers Z Physiol Chem ; 363(8): 789-96, 1982 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-7118074

RESUMO

The complete primary structures of the gamma-chains of fetal sheep (Ovis ammon) and goat (Capra aegagrus) hemoglobins are presented. The chains were isolated by chromatography on carboxymethyl cellulose CM-52. The primary structures of both chains were established by automatic Edman degradation, mainly on the tryptic peptides. The N-terminal regions were sequenced on the chains. Large C-terminal peptides were isolated and sequenced after acidic hydrolysis of the Asp-Pro bond (gamma 99/100). The peptides were aligned by their homology with the bovine gamma-chains. The gamma-chains of sheep and goat differ in 5 amino acid residues. Compared to bovine gamma-chains there are 12 and 10 exchanges, respectively. The influence of the primary structure on the intrinsic oxygen affinity of hemoglobins is discussed.


Assuntos
Cabras/sangue , Hemoglobinas , Ovinos/sangue , Sequência de Aminoácidos , Animais , Substâncias Macromoleculares , Fragmentos de Peptídeos/análise , Especificidade da Espécie , Tripsina
13.
Hoppe Seylers Z Physiol Chem ; 363(10): 1209-15, 1982 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-7141404

RESUMO

The hemoglobin of the egyptian fruit bat (Rousettus aegyptiacus) has only one component. The alpha and beta chains were separated by chromatography on CM-52 cellulose. The complete primary structures of both chains were established by automatic Edman degradation of the chains and the tryptic peptides. The alignment was done by homology with alpha and beta chains of adult human hemoglobin. A comparison of these two hemoglobins shows an exchange of 14 amino acid residues in the alpha chains and of 19 in the beta chains. These numbers are very low, considering the long phylogenetic distance between primates and megachiroptera. In the surroundings of the heme we found one substitution in each chain. In the alpha 1 beta 1-subunit interface one and two residues are exchanged respectively in the alpha and beta chains. The primary structure points to a normal oxygen affinity of the bat hemoglobin which was also found by Jürgens et al.


Assuntos
Quirópteros/sangue , Hemoglobinas , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Fenômenos Químicos , Química , Hidrólise , Fragmentos de Peptídeos/análise , Tripsina
14.
Biomed Biochim Acta ; 42(6): 685-95, 1983.
Artigo em Alemão | MEDLINE | ID: mdl-6639644

RESUMO

Only one hemoglobin component was found in the bottlenosed dolphin (Tursiops truncatus, Cetacea). The alpha and beta chains were separated by chromatography on CM-52 cellulose. The complete primary structures of both chains were established by automatic Edman degradation of the chains and the tryptic peptides. The alignment was done by homology with alpha und beta chains of adult human hemoglobin. A comparison of these two hemoglobins shows an exchange of 22 amino acid residues in the alpha chains and of 20 in the beta chains which corresponds to the phylogenetic distance between primates and cetacea. In the surroundings of the heme we found one substitution in the beta chains. In the alpha 1 beta 1 subunit interphase three and four residues are exchanged respectively in the alpha and beta chains. The possible influence of two exchanges in the alpha 1 beta 2 contact region (alpha 38 (C3) Thr leads to Ser and alpha 44 (CD2) Pro leads to Ser) on the oxygen affinity is discussed. Compared with hemoglobins of terrestrial mammals the primary structure of dolphin hemoglobin shows no amino acid substitutions, which alter the function of the molecule significantly. The adaptation to hypoxic conditions during diving is regulated by other mechanisms.


Assuntos
Golfinhos/sangue , Hemoglobinas , Sequência de Aminoácidos , Animais , Hemoglobinas/genética , Hemoglobinas/isolamento & purificação , Humanos , Substâncias Macromoleculares , Oxigênio/sangue , Fragmentos de Peptídeos/análise , Filogenia , Especificidade da Espécie , Tripsina
15.
Biol Chem Hoppe Seyler ; 370(10): 1139-43, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2514721

RESUMO

The proteolytic specificity of the neutral zinc proteinase from Bacillus mesentericus strain 76 (MCP 76)/Bacillus subtilis was determined by using the alpha-chain of walrus hemoglobin as substrate. The resulting peptides were fractionated by gel filtration and than isolated by reversed-phase HPLC. The peptides were identified on the basis of their amino-acid compositions and aligned with the known sequence of the walrus alpha-chain. The proteolytic specificity of MCP 76, deduced from the experimental cleavage pattern is compared to that of thermolysin. The amino-acid residues in positions P1 and P'1 on both sides of the scissible bond are considered as most important for the cleavage. MCP 76 prefers leucine, valine, phenylalanine and threonine in position P'1 as well as lysine, threonine, leucine and alanine in position P1 and thus differs from thermolysin which shows no preference for threonine in P'1 and accepts numerous amino-acid residues of different type in P1.


Assuntos
Bacillus subtilis/enzimologia , Hemoglobinas/metabolismo , Metaloendopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Quirópteros , Dados de Sequência Molecular , Especificidade por Substrato , Morsas , Zinco
16.
Hoppe Seylers Z Physiol Chem ; 357(12): 1805-8, 1976 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-1017802

RESUMO

The primary structure of the dimeric hemoglobin CTT 11beta from the insect larva Chironomus thummi thummi (Diptera) is given. The sequence of a dimeric hemoglobin is presented for the first time. Some details of this primary structure are discussed and compared with human alpha-chains. The sequence was determined automatically.


Assuntos
Dípteros/metabolismo , Hemoglobinas , Sequência de Aminoácidos , Autoanálise , Fenômenos Químicos , Química , Hemoglobinas/isolamento & purificação
17.
Hoppe Seylers Z Physiol Chem ; 364(9): 1303-13, 1983 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-6629339

RESUMO

The chromatography of the hemoglobin of the rock hyrax (Procavia habessinica) gives two components (73% HbI and 27% HbII). The amino-acid analysis and the sequences of the globin chains elucidated with the phenylthiohydantoin method, did not show any differences between the alpha I and alpha II or beta I and beta II chains, respectively. The different chromatographical behaviour cannot be explained. After chain separation by chromatography on CM-52 cellulose, all four primary structures were elucidated automatically in a sequenator on the chains and the tryptic peptides. In 20% of the beta I chains the N-terminal valine was blocked by acetyl. The alignment was performed by homology with the chains of human adult hemoglobin. The alpha chain of the rock hyrax has 142 amino-acid residues, i.e. one residue more than normal mammalian alpha chains, caused by an insertion of glutamine in the GH region supposed between positions 115 and 116. A comparison of human and hyrax hemoglobins shows an exchange of 21 amino-acid residues in the alpha chains and of 24 in the beta chains. Some substitutions in alpha 1 beta 1 contacts and in the surrounding of the heme are not supposed to effect the function of the hemoglobin. The phylogenetic relationship between the rock hyrax and the Indian elephant (Elephas maximus) on the one hand and with some Perissodactyla on the other, is discussed. Up to now the exchanges of alpha 110(G17)Ala leads to Ser and beta 56(D7)Gly leads to His have only been found in hyrax and elephant. This indicates a certain relationship between Hyracoidea and Proboscidea.


Assuntos
Glutamina , Hemoglobinas , Mamíferos/sangue , Sequência de Aminoácidos , Animais , Elefantes/sangue , Hemoglobina A , Hemoglobinas/isolamento & purificação , Humanos , Substâncias Macromoleculares , Perissodáctilos/sangue , Filogenia , Especificidade da Espécie
18.
Nature ; 351(6325): 394-7, 1991 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-2034288

RESUMO

The origin of tetrapods has been debated for many years. In traditional systematics, the extinct lobe-finned bony fish (Rhipidistia) are regarded as the closest relatives of tetrapods. Among living fish, the coelacanth Latimeria chalumnae (Actinistia), which is the only recent representative of the Crossopterygii (Actinistia and Rhipidistia), the lungfish (Dipnoi) and ray-finned fish (Actinopterygii), have each been considered as sister-groups of the tetrapods. We have now determined the sequence of the alpha- and beta-globin chains of coelacanth haemoglobin and compared them with all known haemoglobins of bony and cartilaginous fish as well as those of tadpoles and adult amphibians. Haemoglobins of bony fish match more closely those of larval than adult amphibians. The beta chains of Latimeria match those of tadpoles more closely (54%) than do those of any other fish, whereas the alpha chains of Latimeria (45.4%), and especially of teleosts (49.2%), are closer to those of larval amphibians than are those of lungfish (39.8%). If only synapomorphous sequence matches (those at derived positions shared by one bony fish and tadpoles but not by any other bony fish) are considered, both Latimeria globin chains have distinctly more identities with phase of tadpoles than do those of any bony fish. Thus the primary structure of Latimeria haemoglobin indicates that the coelacanth is the closest living relative of tetrapods.


Assuntos
Peixes/genética , Globinas/genética , Sequência de Aminoácidos , Animais , Evolução Biológica , Humanos , Dados de Sequência Molecular , Filogenia , Rana catesbeiana/genética , Xenopus/genética
19.
J Mol Evol ; 18(1): 9-14, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6801267

RESUMO

The monomeric hemoglobins of Chironomus tentans and C. pallidivittatus have been isolated and separated into their respective components by gel chromatography on Sephadex G-75 and ion-exchange chromatography on DEAE-Sephacel. The amino acid compositions of the purified components are given. The sequence of the 30 N-terminal amino acid residues of one of the monomeric components (Hb I from C. pallidivittatus) was determined and found to be identical in almost all of its parts with the monomeric hemoglobins of C. thummi (CTT III and CTT IV). Antibodies against the monomeric hemoglobins Hb I and Hb IIc and the dimeric fraction were highly specific and no cross reaction between dimeric and monomeric hemoglobins could be demonstrated. The antibodies against the monomers crossreact with the monomeric hemoglobins CTT III and CTT IV of C. thummi. Taken together with genetic data, the immunological results indicate that divergence of monomeric from dimeric forms was an early event in the evolution of the various hemoglobins in Chironomus.


Assuntos
Evolução Biológica , Chironomidae/análise , Dípteros/análise , Hemoglobinas/análise , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Cromatografia , Eletroforese , Hemoglobinas/imunologia , Imunodifusão , Larva
20.
Biol Chem Hoppe Seyler ; 367(12): 1243-9, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3828074

RESUMO

The hemoglobin of the Mouse-Eared Bat Myotis velifer consists of one component. We present the primary structures of the alpha- and beta-globin chains which have been separated by chromatography on carboxymethyl-cellulose CM-52. The sequences have been determined by Edman-degradation with the film technic or the gas phase method, using the native chains and the tryptic peptides, as well as the C-terminal prolyl-peptides obtained by acid hydrolysis of the Asp-Pro-bonds. Compared to the corresponding human chains we found only 13 substitutions in the alpha-chains, but 27 in the beta-chains. The amino-acid residues substituted in the alpha-chains are not involved in any contacts, whereas in the beta-chains, one exchange involves a heme contact, three alpha 1/beta 1- and one alpha 1/beta 2-contacts, the latter [beta 43(CD2)-Glu----Thr] brings for the first time threonine in this position of the beta-chains. Comparison with the Egyptian Fruit Bat (Rousettus aegyptiacus) shows 12 and 25 substitutions in the alpha- and beta-chains, respectively, suggesting a large phylogenetic distance between Micro- and Megachiroptera. We consider this primary structure as a contribution towards solving the problem of the origin of bats and their relation to primates.


Assuntos
Quirópteros/sangue , Hemoglobinas , Sequência de Aminoácidos , Animais , Humanos , Filogenia , Especificidade da Espécie
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