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1.
Methods Inf Med ; 53(2): 73-81, 2014.
Article in English | MEDLINE | ID: mdl-24549290

ABSTRACT

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.


Subject(s)
Computer Systems , Databases as Topic , Electronic Health Records/organization & administration , Health Information Exchange , Medical Record Linkage , Medical Records Systems, Computerized/organization & administration , Models, Organizational , Germany , Humans , Organizational Objectives
2.
Methods Inf Med ; 51(3): 199-209, 2012.
Article in English | MEDLINE | ID: mdl-21915435

ABSTRACT

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.


Subject(s)
Delivery of Health Care, Integrated/organization & administration , Medical Informatics/organization & administration , Patient-Centered Care/organization & administration , Telemedicine/organization & administration , Computer Systems , Cooperative Behavior , Geography , Germany , Humans , Methicillin-Resistant Staphylococcus aureus , Program Evaluation , Registries
3.
Rofo ; 182(10): 900-4, 2010 Oct.
Article in German | MEDLINE | ID: mdl-20725878

ABSTRACT

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.


Subject(s)
Dimethyl Sulfoxide/therapeutic use , Embolization, Therapeutic/methods , Hemoperitoneum/therapy , Hemothorax/therapy , Polyvinyls/therapeutic use , Aged , Angiography , Female , Follow-Up Studies , Hemoperitoneum/diagnostic imaging , Hemoperitoneum/etiology , Hemothorax/diagnostic imaging , Hemothorax/etiology , Humans , Male , Recurrence , Retreatment
5.
Diabetes Obes Metab ; 11(3): 223-33, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18564175

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetic Angiopathies/drug therapy , Diabetic Neuropathies/drug therapy , Enzyme Inhibitors/therapeutic use , Heterocyclic Compounds, 3-Ring/therapeutic use , Hypoglycemic Agents/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Animals , Blood Flow Velocity/drug effects , Diabetes Mellitus, Type 2/physiopathology , Diabetic Angiopathies/physiopathology , Diabetic Neuropathies/physiopathology , Male , Neprilysin/antagonists & inhibitors , Neural Conduction/drug effects , Neural Conduction/physiology , Rats , Rats, Zucker , Sciatic Nerve/drug effects , Sciatic Nerve/physiopathology
6.
Diabetes Obes Metab ; 10(1): 64-74, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17970755

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Type 2/etiology , Diabetic Angiopathies/etiology , Diabetic Neuropathies/etiology , Neural Conduction , Obesity/physiopathology , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetic Angiopathies/drug therapy , Diabetic Angiopathies/metabolism , Diabetic Neuropathies/drug therapy , Diabetic Neuropathies/metabolism , Male , Motor Neurons/physiology , Rats , Rats, Zucker , Treatment Outcome
8.
J Mol Evol ; 47(4): 471-85, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9767692

ABSTRACT

Phylogenetic relationships among reptiles were examined using previously published and newly determined hemoglobin sequences. Trees reconstructed from these sequences using maximum-parsimony, neighbor-joining, and maximum-likelihood algorithms were compared with a phylogenetic tree of Amniota, which was assembled on the basis of published morphological data. All analyses differentiated alpha chains into alphaA and alphaD types, which are present in all reptiles except crocodiles, where only alphaA chains are expressed. The occurrence of the alphaD chain in squamates (lizards and snakes only in this study) appears to be a general characteristic of these species. Lizards and snakes also express two types of beta chains (betaI and betaII), while only one type of beta chain is present in birds and crocodiles. Reconstructed hemoglobin trees for both alpha and beta sequences did not yield the monophyletic Archosauria (i.e., crocodilians + birds) and Lepidosauria (i.e., Sphenodon + squamates) groups defined by the morphology tree. This discrepancy, as well as some other poorly resolved nodes, might be due to substantial heterogeneity in evolutionary rates among single hemoglobin lineages. Estimation of branch lengths based on uncorrected amino acid substitutions and on distances corrected for multiple substitutions (PAM distances) revealed that relative rates for squamate alphaA and alphaD chains and crocodilian beta chains are at least twice as high as those of the rest of the chains considered. In contrast to these rate inequalities between reptilian orders, little variation was found within squamates, which allowed determination of absolute evolutionary rates for this subset of hemoglobins. Rate estimates for hemoglobins of lizards and snakes yielded 1.7 (alphaA) and 3.3 (beta) million years/PAM when calibrated with published divergence time vs. PAM distance correlates for several speciation events within snakes and for the squamate left and right arrow sphenodontid split. This suggests that hemoglobin chains of squamate reptiles evolved approximately 3.5 (alphaA) or approximately 1.7 times (beta) faster than their mammalian equivalents. These data also were used to obtain a first estimate of some intrasquamate divergence times.


Subject(s)
Evolution, Molecular , Genetic Variation , Hemoglobins/genetics , Phylogeny , Reptiles/classification , Reptiles/genetics , Alligators and Crocodiles/genetics , Animals , Decision Trees , Lizards/genetics , Reptiles/blood , Snakes/genetics , Time , Turtles/genetics
9.
Biochim Biophys Acta ; 1383(1): 55-62, 1998 Mar 03.
Article in English | MEDLINE | ID: mdl-9546046

ABSTRACT

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).


Subject(s)
Myoglobin/chemistry , Polychaeta/chemistry , Amino Acid Sequence , Animals , Aplysia , Molecular Sequence Data , Point Mutation , Protein Structure, Secondary , Sequence Homology, Amino Acid , Species Specificity , Whales
10.
Biol Chem Hoppe Seyler ; 376(10): 603-9, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8590629

ABSTRACT

The hemoglobin of the lobe-lipped bat (Chalinolobus morio, Vespertilionidae) is composed of 45% HbI and 55% HbII. Both components show identical alpha-chains but differ at the following three positions of their beta-chains: beta I/beta II 21: Glu/Asp, 70: Ser/Ala, and 135: Gln/Leu. High performance liquid chromatography revealed pure alpha-chains and a mixture of only partly separated beta-chains. Based on this material, the primary structures of all three globin chains could be achieved by automatic Edman degradation of the whole chains and peptides obtained by trypsin hydrolysis. Compared to human hemoglobin, Chalinolobus shows 17 replacements in the alpha-chains and 24/22 in the beta-chains. A sequence comparison of the globin chains from the three vespertilionid bats Chalinolobus morio and Myotis velifer (Vespertilioninae) as well as Antrozous pallidus (Nyctophilinae) supports a close relationship of the former only for the beta-chains. Molecular modeling showed that the replacements involved in three alpha 1/beta 1 and one alpha 1/beta 2 subunit interface contacts do not cause any interruption. All phosphate binding sites and amino acid residues responsible for the Bohr effect are unchanged. Thus normal physiological properties should be expected for Chalinolobus morio hemoglobin.


Subject(s)
Chiroptera/blood , Hemoglobins/chemistry , Amino Acid Sequence , Amino Acids/analysis , Animals , Blood Protein Electrophoresis , Electrophoresis, Polyacrylamide Gel , Erythrocytes/chemistry , Globins/analysis , Models, Molecular , Molecular Sequence Data , Peptides/analysis
11.
Biol Chem Hoppe Seyler ; 375(6): 379-85, 1994 Jun.
Article in English | MEDLINE | ID: mdl-7980869

ABSTRACT

The amino acid sequence of the cysteine proteinase CC-III from the latex of the subtropical species Carica candamarcensis Hook has been determined with the exception of seven residues (pos. 180-186). It was deduced from the sequence analysis of the whole chain and peptides obtained by tryptic, chymotryptic, peptic and thermolysinolytic hydrolysis. CC-III consists of 214 amino acid residues. Out of a total of eight cysteine residues, six are located at positions involved in the formation of the three disulfide bridges stabilizing the structure of papain related enzymes. CC-III from Carica candamarcensis is a glycoprotein with the carbohydrate moiety bound to asparagine at position 44. Out of 210 residues compared with the sequences of the four cysteine proteinases of Carica papaya L., CC-III shares 125 identical ones (59.5%) with papain, 142 (67.6%) with papaya proteinase IV, 146 (69.5%) with papaya proteinase III and 156 (74.3%) with chymopapain. All amino acid residues constituting the active site and subsite S2 in chymopapain are conserved in CC-III with the exception of the substitution Leu157--> Val in the latter. This fact as well as the highest degree of identity between CC-III and chymopapain point to a similar specificity of both enzymes and thus CC-III might be a suitable substitute for chymopapain as a chemonucleolytic agent.


Subject(s)
Cysteine Endopeptidases/chemistry , Glycoproteins/chemistry , Plants, Medicinal/enzymology , Amino Acid Sequence , Amino Acids/analysis , Carbohydrates/analysis , Chromatography, Gel , Latex/chemistry , Methylation , Molecular Sequence Data , Oxidation-Reduction , Peptides/analysis , Peptides/isolation & purification , Protein Structure, Secondary
12.
Biol Chem Hoppe Seyler ; 374(7): 501-6, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8216902

ABSTRACT

The cysteine-proteinase chymopapain from Carica papaya L. is used for chemonucleolysis of damaged human intervertebral spinal discs. The purification of this enzyme is difficult. To overcome these problems, we were looking for a substitute among the cysteine-proteinases of Carica candamarcensis Hook. The latex from unripe fruits was collected in an aqueous solution of methylethanethiolsulfonate to prevent proteolytic activities. The soluble fraction of the lypophilized product provided four enzymatically active peaks (CC-I-CC-IV) during chromatography on CM-Sephadex C-50 in sodium acetate buffer, pH5.0. They could be further purified by rechromatography under similar conditions. The isolated enzymes have been characterized by PAGE, analysis of the Fourier transform infrared spectra, preliminary studies of their specificities as well as a comparison of the N-terminal amino-acid sequences up to position 43. CC-III proved to be glycosylated. CC-I and CC-III from Carica candamarcensis Hook are suggested to correspond to papain and chymopapain from Carica papaya L., respectively.


Subject(s)
Cysteine Endopeptidases/metabolism , Latex/analysis , Plants/enzymology , Amidohydrolases/analysis , Amino Acid Sequence , Antibody Specificity , Chromatography, Ion Exchange , Chymopapain/analysis , Electrophoresis, Polyacrylamide Gel , Fourier Analysis , Molecular Sequence Data , Spectrophotometry, Infrared
13.
Biol Chem Hoppe Seyler ; 373(9): 937-42, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1466792

ABSTRACT

The primary structures of the alpha- and beta-chains of the single hemoglobin component from the tomb bat (Taphozous georgianus, Microchiroptera) are presented. After chain separation by reversed-phase HPLC the sequences could be determined by automatic gas and liquid phase Edman degradation of the chains and their tryptic peptides. The alpha- and beta-chains differ from human hemoglobin by 14 and 18 replacements, respectively. Compared to the total number of amino-acid exchanges, the exchange rate in the interhelical regions of the alpha-chains is surprisingly high (25%). It seems unlikely that substitutions at contact positions affect the oxygen binding properties of the hemoglobin.


Subject(s)
Chiroptera/blood , Hemoglobins/chemistry , Amino Acid Sequence , Animals , Molecular Sequence Data
14.
Electrophoresis ; 13(1-2): 65-72, 1992.
Article in English | MEDLINE | ID: mdl-1587257

ABSTRACT

Methods for the separation of peptides on a new type of thin-layer chromatography (TLC) sheet and blotting onto polyvinylidene difluoride (PVDF) membranes with subsequent gas phase sequencing are described. For validation, the A and B chain of insulin were chromatographed on Empore TLC sheets and either extracted or blotted onto PVDF membranes. The advantages and disadvantages of thin-layer chromatography on Empore sheets versus high performance liquid chromatography (HPLC) are discussed, along with the possibility of combining the two methods. In addition, TLC was combined with electrophoresis (fingerprinting) for the separation of complex peptide mixtures. Blotting from TLC sheets onto PVDF membranes was performed in two ways: contact diffusion and electrophoretic transfer. In our experiments electroblotting was more effective. Amino acid sequence determination of the B chain of insulin was possible both after extraction from the TLC sheet and after blotting onto PVDF membranes. In the former case, liquid phase sequencing and, in the latter case, gas phase sequencing was performed. The possibility to blot from TLC sheets onto membranes, e.g. PVDF, may prove useful in many fields, for example in biochemistry, and in molecular and cell biology.


Subject(s)
Chromatography, Thin Layer/instrumentation , Gases , Membranes, Artificial , Peptides/isolation & purification , Polyvinyls , Amino Acid Sequence , Immunoblotting
15.
Biol Chem Hoppe Seyler ; 372(12): 1089-95, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1789934

ABSTRACT

The Australian ghost bat (Macroderma gigas, Microchiroptera) has two hemoglobin components in the ratio 3:2. They share identical beta-chains and differ by three replacements in the alpha-chains. The primary structures of all three chains are presented. They could be separated by high-performance liquid chromatography. The sequences were determined by automatic liquid and gas phase Edman degradation of the chains and their tryptic peptides. The two alpha-chains show 18 and 19 and the beta-chains 15 exchanges compared to human alpha- and beta-chains, respectively. The divergent evolution of Macroderma gigas and Megaderma lyra, two representatives of the family Megadermatidae, is discussed. An influence of replacements at functionally important positions on the hemoglobin oxygen affinity seems unlikely.


Subject(s)
Chiroptera , Hemoglobins/chemistry , Adult , Amino Acid Sequence , Animals , Globins/chemistry , Globins/isolation & purification , Hemoglobins/isolation & purification , Humans , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/isolation & purification , Protein Conformation , Species Specificity
16.
Biol Chem Hoppe Seyler ; 372(11): 975-89, 1991 Nov.
Article in English | MEDLINE | ID: mdl-1793518

ABSTRACT

The primary structures of the alpha- and beta-hemoglobin chains of the lesser hedgehog tenrec (Echinops telfairi, Zalambdodonta) are presented. Chain separation was performed by carboxymethyl-cellulose chromatography. The peptides, obtained by tryptic digestion of the oxidized chains, were prefractionated by gel chromatography and isolated by reversed-phase HPLC. For sequence analysis gas and liquid phase sequencers were employed. The tenrec hemoglobin consists of one alpha- and two beta-chains the latter occurring in a 1:1 ratio and differing in beta 16 Gly/Cys and beta 118 Phe/Leu. Two external cysteine residues at beta 16 and beta 52 cause reversible polymerization to octamers and most likely irreversible formation of higher polymers. A comparison of the whole chains and certain positions of tenrec hemoglobin with those of Insectivora sensu strictu, Scandentia and Proto- and Metatheria corroborates a long and independent evolution of tenrec and its phylogenetic isolation from the Insectivora s.str. (hedgehog, musk shrew and mole). Replacements at positions involved in heme and subunit interface contacts are discussed. Compared to human hemoglobin the tenrec pigment shows a low intrinsic oxygen affinity as well as lower chloride and temperature sensitivities, a reduced Bohr effect and a strong response to 2,3-DPG. The possible adaptive significance of these properties is discussed in relation to the large diurnal body temperature variations seen in tenrecs.


Subject(s)
Hedgehogs/blood , Hemoglobins/metabolism , Oxygen Consumption/physiology , Amino Acid Sequence , Amino Acids/analysis , Animals , Chromatography, Gel , Chromatography, High Pressure Liquid , Erythrocytes/chemistry , Globins/analysis , Globins/isolation & purification , Hemoglobins/analysis , Hemoglobins/genetics , Hydrolysis , Molecular Sequence Data , Phylogeny , Trypsin
17.
Biol Chem Hoppe Seyler ; 372(8): 599-612, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1958318

ABSTRACT

The coelacanth (Latimeria chalumnae, Actinistia) has a single hemoglobin component. The primary structures of the alpha- and beta-chains are presented. They could be separated by reversed-phase HPLC. Peptides obtained by tryptic digestion of the native and oxidized chains were isolated by reversed-phase HPLC and sequenced in liquid and gas-phase sequenators. The alignment was achieved by employing the N-terminal sequences of the native chains and those of a beta-chain cyanogen bromide peptide as well as fragments obtained by acid hydrolysis. The Latimeria alpha-chains consist of 142 amino-acid residues, due to a fish-specific insertion between positions 46 and 47, whereas the beta-chains are of normal length (146 residues). Latimeria alpha- and beta-chains share 72 (51.1%) and 70 (47.9%) identical residues with human hemoglobin, respectively. Numerous heme contacts and positions involved in subunit interface contacts are replaced. The most interesting of them were studied by molecular modeling. The loss of an alpha 1/beta 2-contact by the exchanges alpha 92(FG4)Arg----Leu and beta 43(CD2)Glu----Lys might be responsible for the easy dissociation of the tetrameric hemoglobin molecule. A comparison of the residues replaced in contact positions with fishes and amphibians revealed the highest number of matches between Latimeria and tadpoles. The same result was obtained by the evaluation of other regions relevant for structure and function of the molecule, like exon-intron boundary regions, phosphate binding sites and salt bridges responsible for the Bohr effect.


Subject(s)
Amphibians/genetics , Fishes/genetics , Fossils , Hemoglobins/genetics , Amino Acid Sequence , Animals , Biological Evolution , Electrophoresis, Polyacrylamide Gel , Fishes/blood , Hemoglobins/chemistry , Humans , Macromolecular Substances , Molecular Sequence Data , Phylogeny , Protein Conformation , Sequence Homology, Nucleic Acid
18.
Biol Chem Hoppe Seyler ; 372(6): 393-9, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1910578

ABSTRACT

The hemoglobin of the aardwolf (Proteles cristatus) contains only one component. In this paper, we are presenting its primary structure. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas-phase Edman degradation of the chains and their tryptic peptides. The alpha- as well as the beta-chains show 20 exchanges compared with the corresponding human chains. The difference to the masked palm civet (Paguma larvata) and the spotted hyaena (Crocuta crocuta) is marked by 16 and 4 replacements in the alpha-chains and by 10 and 1 in the beta-chains, thus supporting the hyaenid character of the aardwolf. The exchanges at contact positions are shared by other carnivoran hemoglobins.


Subject(s)
Carnivora/genetics , Hemoglobins/genetics , Amino Acid Sequence , Animals , Chromatography, High Pressure Liquid , Haplorhini/genetics , Hemoglobin A/genetics , Humans , Macromolecular Substances , Molecular Sequence Data , Peptide Fragments/isolation & purification , Phylogeny , Sequence Homology, Nucleic Acid
19.
Nature ; 351(6325): 394-7, 1991 May 30.
Article in English | MEDLINE | ID: mdl-2034288

ABSTRACT

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.


Subject(s)
Fishes/genetics , Globins/genetics , Amino Acid Sequence , Animals , Biological Evolution , Humans , Molecular Sequence Data , Phylogeny , Rana catesbeiana/genetics , Xenopus/genetics
20.
Biol Chem Hoppe Seyler ; 371(7): 641-8, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2222863

ABSTRACT

The primary structure of the hemoglobin from guanaco (Lama guanacoë, Tylopoda) is presented. It could be separated into the chains by CM-cellulose chromatography. The sequences have been determined by automatic Edman degradation with the film technique or gas phase method, using the native chains and the tryptic peptides of the oxidized chains as well as a fragment obtained by acid hydrolysis. Guanaco hemoglobin has identical alpha-chains with alpaca and identical beta-chains with all Lama species with the exception that one guanaco in this study had alanine and serine in the ratio 1:1 in position beta 135 whereas a second individual had alanine only. Since the data suggest that the domesticated species llama and alpaca originate from the guanaco, it seems likely that beta 135Ala is the common form. Guanaco, llama, and alpaca show a comparable high blood oxygen affinity, caused by the substitution beta 2(NA2)His----Asn, as an adaptation to life at high altitude.


Subject(s)
Camelids, New World/metabolism , Hemoglobins/metabolism , Oxygen/metabolism , Amino Acid Sequence , Animals , Molecular Sequence Data , Species Specificity
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