Hucho F


Full name : Hucho Ferdinand

First name : Ferdinand

Mail : Freie Universitat Berlin, Institut fur Biochemie, Thielallee 63, D-14195 Berlin

Zip Code :

City :

Country : Germany

Email :

Phone :

Fax :

Website : \/\/\/wiki\/Ferdinand_Hucho

Directory :

References (29)

Title : Structure-activity relationships of methoctramine-related polyamines as muscular nicotinic receptor noncompetitive antagonists. 3. Effect of inserting the tetraamine backbone into a macrocyclic structure - Bolognesi_2002_J.Med.Chem_45_3286
Author(s) : Bolognesi ML , Bixel MG , Marucci G , Bartolini M , Krauss M , Angeli P , Antonello A , Rosini M , Tumiatti V , Hucho F , Melchiorre C
Ref : Journal of Medicinal Chemistry , 45 :3286 , 2002
Abstract : The present article expands on the study of another aspect of structure-activity relationships of the polymethylene tetraamines, namely, the effect of inserting the tetraamine backbone into a macrocyclic structure. To this end, compounds 8-12 were designed by linking the two terminal nitrogen atoms of prototype methoctramine 2 to an aryl moiety. Alternatively, 2 was first modified to achieve compounds 6 and 7, which in turn were cyclized by linking the two terminal primary amine functions to a polyphenyl spacer, affording 13-20. All the compounds were tested on muscle-type nAChRs and most of them as well on AChE. Furthermore, selected compounds were tested also on peripheral M(2) and M(3) mAChRs. All these cyclic derivatives, like prototypes, were potent noncompetitive antagonists at both frog and Torpedo nAChRs, suggesting that polyamines do not need to be linear or in extended conformation to optimally interact with the nicotinic channel; rather, they may bind in a U-shaped conformation. Relative to muscarinic activity, macrocyclic compounds 10, 13, 14, and 20, in contrast with the profile displayed by 2, were almost devoid of affinity. It is derived that an aryl spacer is detrimental to the interaction of polyamines with mAChRs. Finally, all the diamine diamides investigated in this study were much less potent in inhibiting AChE activity than prototype 3, suggesting that a macrocyclic structure may not be suitable for AChE inhibition.
ESTHER : Bolognesi_2002_J.Med.Chem_45_3286
PubMedSearch : Bolognesi_2002_J.Med.Chem_45_3286
PubMedID: 12109912

Title : Design, synthesis, and biological evaluation of symmetrically and unsymmetrically substituted methoctramine-related polyamines as muscular nicotinic receptor noncompetitive antagonists - Rosini_1999_J.Med.Chem_42_5212
Author(s) : Rosini M , Budriesi R , Bixel MG , Bolognesi ML , Chiarini A , Hucho F , Krogsgaard-Larsen P , Mellor IR , Minarini A , Tumiatti V , Usherwood PN , Melchiorre C
Ref : Journal of Medicinal Chemistry , 42 :5212 , 1999
Abstract : The universal template approach to drug design foresees that a polyamine can be modified in such a way to recognize any neurotransmitter receptor. Thus, hybrids of polymethylene tetraamines and philanthotoxins, exemplified by methoctramine (1) and PhTX-343 (2), respectively, were synthesized to produce novel inhibitors of muscular nicotinic acetylcholine receptors. Polyamines 3-25 were synthesized and their biological profiles were evaluated at frog rectus abdominis muscle nicotinic receptors and guinea pig left atria (M(2)) and ileum longitudinal muscle (M(3)) muscarinic acetylcholine receptors. All of the compounds, like prototypes 1 and 2, were noncompetitive antagonists of nicotinic receptors while being, like 1, competitive antagonists at muscarinic M(2) and M(3) receptor subtypes. Interestingly, polyamines bearing a low number of methylenes between the nitrogen atoms, as in 3, 6, and 7, displayed a biological profile similar to that of 2: a noncompetitive antagonism at nicotinic receptors in the 7-25 microM range while not showing any antagonism for muscarinic receptors up to 10 microM. Increasing the number of methylenes separating these nitrogen atoms in methoctramine-related tetraamines resulted in a significant improvement in potency at nicotinic receptors. The most potent tetraamine was 19, bearing a 12 methylene spacer between the nitrogen atoms, which was 12-fold and 250-fold more potent than prototypes 1 and 2, respectively. Tetraamines 9-11, bearing a rather rigid spacer between the nitrogen atoms instead of the very flexible polymethylene chain, displayed a profile similar to that of 1 at nicotinic receptors, whereas a significant decrease in potency was observed at muscarinic M(2) receptors. This finding may have relevance in understanding the mode of interaction with these receptors. Similarly, the constrained analogue 12 of methoctramine showed a decrease in potency at nicotinic and muscarinic M(2) receptors, revealing that the tricyclic system, which incorporates the 2-methoxybenzylamine moiety of 1, does not represent a good pharmacophore for activity at these sites. A most intriguing finding was the observation that the photolabile tetraamine 22 was more potent than methoctramine at nicotinic receptors and, what is more important, it inhibited a closed state of the receptor.
ESTHER : Rosini_1999_J.Med.Chem_42_5212
PubMedSearch : Rosini_1999_J.Med.Chem_42_5212
PubMedID: 10602706

Title : Butyrylcholinesterase is complexed with transferrin in chicken serum - Weitnauer_1999_J.Protein.Chem_18_205
Author(s) : Weitnauer E , Ebert C , Hucho F , Robitzki AA , Weise C , Layer PG
Ref : J Protein Chem , 18 :205 , 1999
Abstract : The function of the enzyme butyrylcholinesterase (BChE) both in serum and in brain is unclear. In serum, BChE has been found complexed with several biomedically relevant proteins, with which it could function in concert. Here, the existence of a similar complex formed between BChE and sero-transferrin from adult chicken serum was elucidated. In order to identify both proteins unequivocally, we improved methods to highly purify the 81-kDa BChE and the coisolated 75-kDa transferrin, which then allowed us to tryptically digest and sequence the resulting peptides. The sequences as revealed for BChE peptides were highly identical to mammalian BChEs. A tight complex formation between the two proteins could be established (a) since transferrin is coisolated along with BChE over three steps including procainamide affinity chromatography, while transferrin alone is not bound to this affinity column, and (b) since imunoprecipitation experiments of whole serum with a transferrin-specific antiserum allows us to detect BChE in the precipitate with the BChE-specific monoclonal antibody 7D11. The possible biomedical implications of a complex between transferrin and BChE which here has been shown to exist in chicken serum are briefly discussed.
ESTHER : Weitnauer_1999_J.Protein.Chem_18_205
PubMedSearch : Weitnauer_1999_J.Protein.Chem_18_205
PubMedID: 10333295

Title : The acetylcholinesterase (AChE) of the cobra Naja naja oxiana. Identification of residues involved in insensitivity towards fasciculin -
Author(s) : Weise C , Bon C , Hucho F , Cousin X
Ref : Journal de Physiologie (Paris) , 92 :508 , 1998

Title : Labeling of Torpedo californica nicotinic acetylcholine receptor subunits by cobratoxin derivatives with photoactivatable groups of different chemical nature at Lys23 - Utkin_1998_Eur.J.Biochem_253_229
Author(s) : Utkin YN , Krivoshein AV , Davydov VL , Kasheverov IE , Franke P , Maslennikov IV , Arseniev AS , Hucho F , Tsetlin VI
Ref : European Journal of Biochemistry , 253 :229 , 1998
Abstract : Different photoactivatable derivatives of toxin 3 (CTX) Naja naja siamensis were obtained after CTX reaction with N-hydroxysuccinimide esters of p-azidobenzoic, p-azidotetraflourobenzoic, p-benzoylbenzoic and p-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzoic acids. The ion-exchange HPLC profiles for the reaction products were very similar in four cases, with one predominant peak corresponding to the derivative containing the label at Lys23. After [125I]iodination, CTX photoactivatable derivatives were cross-linked to the nicotinic acetylcholine receptor from Torpedo californica under optimized conditions. The highest cross-linking yield (up to 16% of the bound toxin) was observed for azidobenzoyl-Lys23-CTX. Different receptor subunits were found to be labelled depending on the nature of the photoactivatable group: the azido derivatives labelled the gamma and delta subunits, benzoylbenzoyl derivative labelled the alpha and delta subunits, while p-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzoyl derivative reacted with alpha, gamma and delta subunits. The cross-linking experiments in the presence of varying concentrations of (+)-tubocurarine demonstrated that the Lys23-attached diazirinyl group contacts the delta and alpha subunits in one ligand-binding site, whereas at the other site, for another CTX molecule, the contacts of the Lys23-diazirinyl are with gamma and alpha subunits. This means that the central loop in the two CTX molecules binds at the alpha/gamma and alpha/delta interfaces. Calculation of the sterically possible displacement of diazirinyl nitrogen, basing on the known X-ray structure of CTX, showed that this value does not exceed 13 A. The results obtained favor the disposition of the ligand-binding sites at the subunit interfaces, with the distance between alpha and delta, or alpha and gamma subunits at these sites being not more than 13 A.
ESTHER : Utkin_1998_Eur.J.Biochem_253_229
PubMedSearch : Utkin_1998_Eur.J.Biochem_253_229
PubMedID: 9578481

Title : Mapping of exposed surfaces of the nicotinic acetylcholine receptor by identification of iodinated tyrosine residues - Mund_1997_J.Protein.Chem_16_161
Author(s) : Mund M , Weise C , Franke P , Hucho F
Ref : J Protein Chem , 16 :161 , 1997
Abstract : Here we report on the use of iodination of the membrane-bound nicotinic acetylcholine receptor (nAChR) from Torpedo californica electric tissue in order to define surface-exposed portions of the receptor molecule. Membrane-bound nAChR was 125I-iodinated using the oxidation agent Iodo-Gen. The iodinated subunits were separated by preparative gel electrophoresis, desalted, and cleaved with trypsin. The resulting peptides were separated by reverse-phase HPLC and the radioactive peptides were identified by mass spectrometry and protein sequencing. For the delta-subunit, we identified five iodinated peptides containing the tyrosine residues deltaTyr17, deltaTyr74, deltaTyr365, deltaTyr372, and deltaTyr428. The surface exposition of these amino acids is in agreement with the four-transmembrane-segment model (4TM model) of the nAChR, but the assignment to the intra- or extracellular surface is doubtful. According to this model, the N-terminal portion of the receptor subunits including the iodinated residues deltaTyr17 and deltaTyr74 is extracellular and deltaTyr372 as a site of tyrosine phosphorylation is located on the cytoplasmic side. But since this latter residue is among the first to be iodinated using an immobilized iodination agent, its true position with respect to the membrane bilayer is not clear.
ESTHER : Mund_1997_J.Protein.Chem_16_161
PubMedSearch : Mund_1997_J.Protein.Chem_16_161
PubMedID: 9155087

Title : [Effective binding of alpha-bungarotoxin with the solubilized alpha-subunit of Torpedo californica acetylcholine receptor] - Utkin_1996_Bioorg.Khim_22_387
Author(s) : Utkin Iu N , Mund M , Hucho F , Tsetlin VI
Ref : Bioorganicheskaia Khimiia , 22 :387 , 1996
Abstract : alpha-Subunit of the Torpedo californica nicotinic acetylcholine receptor was isolated by preparative SDS-PAGE followed by reversed-phase HPLC on a C4 column in an acetonitrile-isopropanol gradient in water. After removal of the organic solvents and solubilization in beta-octylglucoside, the purified alpha-subunit binds alpha-bungarotoxin with high affinity (Kd 28 nM).
ESTHER : Utkin_1996_Bioorg.Khim_22_387
PubMedSearch : Utkin_1996_Bioorg.Khim_22_387
PubMedID: 8929226

Title : FTIR-Spectroscopic Investigations of the Structure and Temperature Stability of the Acetylcholinesterase from Torpedo californica -
Author(s) : Hucho F , Naumann D , Gorne-Tschelnokow U
Ref : In Enzyme of the Cholinesterase Family - Proceedings of Fifth International Meeting on Cholinesterases , (Quinn, D.M., Balasubramanian, A.S., Doctor, B.P., Taylor, P., Eds) Plenum Publishing Corp. :83 , 1995

Title : The neurochemistry of Parkinson's disease--comments on present and future developments - Hucho_1995_J.Neural.Transm.Suppl_46_59
Author(s) : Hucho F
Ref : J Neural Transm Suppl , 46 :59 , 1995
Abstract : The neurochemistry of Parkinson's disease is currently undergoing considerable changes. From the analysis of diseased tissue and of lesion models, attention has turned to basic questions of neuronal development and neuronal death including the role played by trophic factors in the protection and regeneration of nervous tissue. Here some aspects are highlighted which emphasize molecular targets of possible causes and of future therapies, e.g., transmitter transporters and novel trophic effectors.
ESTHER : Hucho_1995_J.Neural.Transm.Suppl_46_59
PubMedSearch : Hucho_1995_J.Neural.Transm.Suppl_46_59
PubMedID: 8821041

Title : Secondary structure and temperature behaviour of acetylcholinesterase. Studies by Fourier-transform infrared spectroscopy - Gorne-Tschelnokow_1993_Eur.J.Biochem_213_1235
Author(s) : Gorne-Tschelnokow U , Naumann D , Weise C , Hucho F
Ref : European Journal of Biochemistry , 213 :1235 , 1993
Abstract : The secondary structure of the acetylcholinesterase and its temperature behaviour have been investigated using Fourier-transform infrared (FTIR) spectroscopy. The data are compared to the structure obtained by X-ray analysis of the crystalline enzyme. The secondary structure was determined using the spectral features observed in the amide-I band (H2O buffer) and amide-I' band (D2O buffer) at 1600-1700 cm-1, taking advantage of resolution-enhancement techniques along with least-squares band-fitting procedures. The relative amounts of different secondary-structure elements, 34-36% for alpha-helices, 19-25% for beta-sheets, 15-16% for turns and 13-17% for irregular structures, were estimated. These data, obtained with the enzyme in solution, correlate well with X-ray data of the crystalline protein [Sussman, J. L., Hard, M., Frolow, F., Oefner, C., Goldman, A., Toker, L. & Silman, I. (1991) Science 253, 872-879]. These results are also in good agreement with those obtained by computing the psi and phi angles of the peptide backbone using the Kabsch and Sanders method [Kabsch, W. & Sanders, C. (1983) Biopolymers 22, 2577-2637]. In conjunction with the X-ray data, two bands in the FTIR spectra were assigned to different populations of long and short alpha-helices. Until now this phenomenon has only been described by theoretical calculations [Nevskaya, N. A. & Chirgadze, Yu. N. (1976) Biopolymers 15, 637-648]. The relationship between the thermally induced loss of enzyme activity and secondary-structure changes has also been investigated. The decrease in enzyme activity to zero at 30-40 degrees C was accompanied only by minor changes in the secondary structure. At 55-60 degrees C, denaturation of AChE occurs. In this temperature range, all bands assigned to the various secondary-structure elements abruptly disappear in a co-operative and irreversible manner, whereas the beta-aggregation bands (at 1622 cm-1 and the corresponding high-frequency band) increase in intensity at the same rate.
ESTHER : Gorne-Tschelnokow_1993_Eur.J.Biochem_213_1235
PubMedSearch : Gorne-Tschelnokow_1993_Eur.J.Biochem_213_1235
PubMedID: 8389298

Title : Nuclear substrates of protein kinase C - Beckmann_1992_Eur.J.Biochem_210_45
Author(s) : Beckmann R , Buchner K , Jungblut PR , Eckerskorn C , Weise C , Hilbert R , Hucho F
Ref : European Journal of Biochemistry , 210 :45 , 1992
Abstract : Starting from the finding that, for neuronal cells, the nuclear-membrane-associated protein kinase C (PKC) is the so-called 'membrane inserted', constitutively active form, we attempted to identify substrates of this nuclear PKC. For this purpose, nuclear membranes and other subcellular fractions were prepared from bovine brain, and in-vitro phosphorylation was performed. Several nuclear membrane proteins were found, the phosphorylation of which was inhibited by specific PKC inhibitors and effectively catalyzed by added PKC. Combining the methods of two-dimensional gel electrophoresis, in-situ digestion, reverse-phase HPLC and microsequencing, two of these nuclear PKC substrates were identified; the known PKC substrate Lamin B2, which serves as a control of the approach and the nucleolar protein B23. Our data suggest, that, for B23, Ser225 is a site of phosphorylation by PKC.
ESTHER : Beckmann_1992_Eur.J.Biochem_210_45
PubMedSearch : Beckmann_1992_Eur.J.Biochem_210_45
PubMedID: 1446684

Title : GTP-binding proteins in bovine brain nuclear membranes - Otto_1992_Neurochem.Int_21_409
Author(s) : Otto H , Buchner K , Beckmann R , Hilbert R , Hucho F
Ref : Neurochem Int , 21 :409 , 1992
Abstract : Nuclear membranes and other subcellular fractions derived from bovine brain cortex were investigated for the existence of GTP-binding proteins. By using photolytic labeling with [alpha-32P]GTP a 29 kDa GTP-binding protein was shown to be present in nuclear membranes which was not present in the plasma membranes nor in microsomal or cytosolic fractions. Two-dimensional gel electrophoresis revealed that this protein is rather acidic with a pI lower than 4.5. Members of the heterotrimeric Gi/o family are not present in the nuclear envelope: a 39 kDa protein, ADP ribosylated by pertussis toxin, was shown to originate from plasma membrane contamination.
ESTHER : Otto_1992_Neurochem.Int_21_409
PubMedSearch : Otto_1992_Neurochem.Int_21_409
PubMedID: 1303165

Title : Structural Investigations of the Acetylcholinesterase -
Author(s) : Hucho F , Weise C
Ref : In Multidisciplinary approaches to cholinesterase functions - Proceedings of Fourth International Meeting on Cholinesterases , (Shafferman, A. and Velan, B., Eds) Plenum Press, New York :121 , 1992

Title : Phosphorylation sites of the nicotinic acetylcholine receptor. A novel site detected in position delta S362 - Schroeder_1991_Biochemistry_30_3583
Author(s) : Schroeder W , Meyer HE , Buchner K , Bayer H , Hucho F
Ref : Biochemistry , 30 :3583 , 1991
Abstract : The delta-subunit of the nicotinic acetylcholine receptor from Torpedo californica electric tissue isolated form receptor purified in the absence of protein phosphatase inhibitors contains a total of four phosphate groups. Three of these are shown to represent phosphoserine groups. The fourth possible represents phosphotyrosine. The phosphate groups are localized within the primary structure: We found phosphoserine in positions delta S361 and delta S377, the predicted sites phosphorylated by PKA and PKC, respectively. In addition, we found that position delta S362 is also phosphorylated. Phosphorylation experiments with the synthetic peptide delta L357-delta K368 show that phosphorylation of this novel site can be catalyzed by PKA and by PKC. It is concluded that the delat-subunit of the acetylcholine receptor is stably and not transiently phosphorylated. Implications for the physiological functions of receptor phosphorylation are discussed.
ESTHER : Schroeder_1991_Biochemistry_30_3583
PubMedSearch : Schroeder_1991_Biochemistry_30_3583
PubMedID: 1707313

Title : Substrate-binding sites in acetylcholinesterase - Hucho_1991_Trends.Pharmacol.Sci_12_422
Author(s) : Hucho F , Jarv J , Weise C
Ref : Trends in Pharmacological Sciences , 12 :422 , 1991
Abstract : Acetylcholinesterase is among the most efficient enzymes known. In order to provide an explanation for its catalytic and regulatory mechanisms, including the high turnover rate, the specific amino acid residues involved in substrate binding and hydrolysis need to be identified. In this article, Ferdinand Hucho, Jaak Jnrv and Christoph Weise describe the topography of the enzyme as deduced from protein chemistry studies. One result of this approach is the finding that the binding pocket for the substrate's cationic cholinium group appears to be hydrophobic rather than anionic.
ESTHER : Hucho_1991_Trends.Pharmacol.Sci_12_422
PubMedSearch : Hucho_1991_Trends.Pharmacol.Sci_12_422
PubMedID: 1796496

Title : Anionic subsites of the catalytic center of acetylcholinesterase from Torpedo and from cobra venom - Kreienkamp_1991_Proc.Natl.Acad.Sci.U.S.A_88_6117
Author(s) : Kreienkamp HJ , Weise C , Raba R , Aaviksaar A , Hucho F
Ref : Proceedings of the National Academy of Sciences of the United States of America , 88 :6117 , 1991
Abstract : A peptide of acetylcholinesterase (AcChoEase; acetylcholine acetylhydrolase, EC from the venom of the cobra Naja naja oxiana labeled by the affinity reagent N,N-dimethyl-2-phenylaziridinium (DPA) has been identified. The sequence is Gly-Ala-Glu-Met-Trp-Asn-Pro-Asn. In AcChoEase from Torpedo californica, a homologous peptide was labeled and isolated. Its sequence is Ser-Gly-Ser-Glu-Met-Trp-Asn-Pro-Asn, representing positions 79 through 87. In both cases labeling can be prevented by 0.1 mM edrophonium, indicating that the respective peptides form part of the anionic subsite of the catalytic center. The modified residue was tryptophan (Trp-84 in Torpedo AcChoEase) in both enzymes. In contrast to AcChoEase from Torpedo, the enzyme from cobra venom does not contain a peripheral anionic binding site.
ESTHER : Kreienkamp_1991_Proc.Natl.Acad.Sci.U.S.A_88_6117
PubMedSearch : Kreienkamp_1991_Proc.Natl.Acad.Sci.U.S.A_88_6117
PubMedID: 2068091

Title : Poster: Partial sequence of cobra venom acetylcholinesterase - AChE and Lysophospholipase have similar Sequences -
Author(s) : Weise C , Kreienkamp HJ , Hucho F , Raba R , Aaviksaar A
Ref : In: Cholinesterases: Structure, Function, Mechanism, Genetics, and Cell Biology , (Massoulie J, Barnard EA, Chatonnet A, Bacou F, Doctor BP, Quinn DM) American Chemical Society, Washington, DC :58 , 1991

Title : Anionic subsites of the acetylcholinesterase from Torpedo californica: affinity labelling with the cationic reagent N,N-dimethyl-2-phenyl- aziridinium - Weise_1990_EMBO.J_9_3885
Author(s) : Weise C , Kreienkamp HJ , Raba R , Pedak A , Aaviksaar A , Hucho F
Ref : EMBO Journal , 9 :3885 , 1990
Abstract : Several peptides of acetylcholinesterase of Torpedo californica labelled with the alkylating reagent [3H]N,N-dimethyl-2-phenyl-aziridinium (DPA) were localized within the primary structure. One peptide had the sequence KPQELIDVE (positions 270-278); the incorporation of DPA into this peptide could be specifically suppressed by propidium, which suggests that it is part of the peripheral anionic site. The incorporation of DPA into two other peptides was insensitive to propidium but could be prevented by edrophonium; the sequence of one of the peptides assumed to be part of the anionic site in the catalytic centre was found to be DLFR (positions 217-220). Decamethonium efficiently blocked alkylation by DPA in all three investigated peptides.
ESTHER : Weise_1990_EMBO.J_9_3885
PubMedSearch : Weise_1990_EMBO.J_9_3885
PubMedID: 2249655

Title : Retraction. Heat-resistant inhibitors of protein kinase C from bovine brain -
Author(s) : Pribilla I , Kruger H , Buchner K , Otto H , Schiebler W , Tripier D , Hucho F
Ref : European Journal of Biochemistry , 188 :204 , 1990
PubMedID: 2180696

Title : The active site and partial sequence of cobra venom acetylcholinesterase - Weise_1990_J.Protein.Chem_9_53
Author(s) : Weise C , Kreienkamp HJ , Raba R , Aaviksaar A , Hucho F
Ref : J Protein Chem , 9 :53 , 1990
Abstract : About 30% of the primary structure of acetylcholinesterase (AchE) from the cobra Naja naja oxiana has been determined. The sequence around the serine residue labeled by diisopropylfluorophosphate (DFP) was found to be TVTLFGESAGAASVGM which is similar to the active sites of AChE from other tissues. The part of the primary structure determined shows 76% identity with AChE from Torpedo and 42% identity with the Drosophila enzyme. A surprisingly large identity (42% in the sequence determined) was found with lysophospholipase from rat.
ESTHER : Weise_1990_J.Protein.Chem_9_53
PubMedSearch : Weise_1990_J.Protein.Chem_9_53
PubMedID: 2340076

Title : 2-D- and 3-D-ordered structures of acetylcholine receptors -
Author(s) : Giersig M , Hertling-Jaweed S , Hucho F
Ref : J Protein Chem , 8 :330 , 1989
PubMedID: 2789676

Title : Symmetry and dimensions of membrane-bound nicotinic acetylcholine receptors from Torpedo californica electric tissue: rapid rearrangement to two-dimensional ordered lattices - Giersig_1989_Membr.Biochem_8_81
Author(s) : Giersig M , Kunath W , Pribilla I , Bandini G , Hucho F
Ref : Membr Biochem , 8 :81 , 1989
Abstract : Computer-aided image-averaging methods are applied to different preparations of membrane-bound nicotinic acetylcholine receptor. Circular harmonic averaging (CHA), a novel, reference-independent averaging method developed by W. Kunath and H. Sack-Kongehl [1989) Ultramicroscopy 27:171-184) allows analyzing images of single molecules of the receptor in its native membrane-bound state. The five subunits of the receptor are clearly resolved. At the resolution obtained (approximately 20 A) no differences were observed with resting and agonist-desensitized receptors. A method is proposed for rapidly arranging the acetylcholine receptors to ordered lattices. Depending on the conditions, tetragonal or hexagonal, two-dimensional lattices can be obtained within 2 to 6 days at 4 degrees C. Analysis by CHA shows that the receptor molecules preserve their gross structure and dimensions in these membranes, but that they are randomly oriented. Both lattices, therefore, do not represent true two-dimensional crystals.
ESTHER : Giersig_1989_Membr.Biochem_8_81
PubMedSearch : Giersig_1989_Membr.Biochem_8_81
PubMedID: 2634235

Title : Rapid preparation of the nicotinic acetylcholine receptor for crystallization in detergent solution - Hertling-Jaweed_1988_FEBS.Lett_241_29
Author(s) : Hertling-Jaweed S , Bandini G , Muller-Fahrnow A , Dommes V , Hucho F
Ref : FEBS Letters , 241 :29 , 1988
Abstract : A novel rapid purification method for the nicotinic acetylcholine receptor from Torpedo electric tissue was developed. It allows preparation of 10 mg quantities of pure and stabile receptor protein within 2 days. This protein is used for crystallization attempts. Conditions are described which reproducibly yield crystals.
ESTHER : Hertling-Jaweed_1988_FEBS.Lett_241_29
PubMedSearch : Hertling-Jaweed_1988_FEBS.Lett_241_29
PubMedID: 3197836

Title : Heat-resistant inhibitors of protein kinase C from bovine brain - Pribilla_1988_Eur.J.Biochem_177_657
Author(s) : Pribilla I , Kruger H , Buchner K , Otto H , Schiebler W , Tripier D , Hucho F
Ref : European Journal of Biochemistry , 177 :657 , 1988
Abstract : Bovine brain cytosol is shown to contain two heat-resistant inhibitors of protein kinase C, with the following characteristics: 1. One protein kinase C inhibitor can be easily purified to homogeneity. Evidence is presented that this polypeptide of Mr 19,000 is calmodulin. It inhibits protein kinase C with an EC50 of about 2.5 microM and the inhibition is Ca2+-independent. It inhibits only intact protein kinase C. Removal of the regulatory domain of protein kinase C, by limited proteolysis with trypsin, abolishes the inhibition. 2. Another protein kinase C inhibitory activity has been partially purified. Its Mr is low (Mr 600-700, as estimated by gel chromatography). It is not digested by proteases, is hydrophilic, acid- and alkali-resistant, acts Ca2+-independently, and, in contrast to calmodulin, inhibits even the catalytic fragment of protein kinase C after removal of the regulatory domain by limited proteolysis. This inhibition is, at least partially, due to a competition with ATP. Besides protein kinase C, calcium/calmodulin-dependent protein kinase II is inhibited to a similar extent. cAMP-dependent protein kinase is not affected.
ESTHER : Pribilla_1988_Eur.J.Biochem_177_657
PubMedSearch : Pribilla_1988_Eur.J.Biochem_177_657
PubMedID: 3058479

Title : A 40 kDa inhibitor of protein kinase C purified from bovine brain - Hucho_1987_FEBS.Lett_211_207
Author(s) : Hucho F , Kruger H , Pribilla I , Oberdieck U
Ref : FEBS Letters , 211 :207 , 1987
Abstract : An inhibitor of protein kinase C has been purified to homogeneity from bovine brain cytosol by a four-step method. It is heat stable, has an apparent molecular mass of 40 kDa and is composed of two polypeptide chains of 19 kDa.
ESTHER : Hucho_1987_FEBS.Lett_211_207
PubMedSearch : Hucho_1987_FEBS.Lett_211_207
PubMedID: 3803599

Title : Interactions of bisquaternary pyridine salts (H-oximes) with cholinergic receptors - Kuhnen-Clausen_1983_Arch.Toxicol_54_171
Author(s) : Kuhnen-Clausen D , Hagedorn I , Gross G , Bayer H , Hucho F
Ref : Archives of Toxicology , 54 :171 , 1983
Abstract : Certain recently developed antidotes of the bispyridinium type, commonly called "H-oximes" (HGG 12, 21, 42, 52, 65, 70, 89, and HGG 90) have been investigated as to their effects on muscarinic and nicotinic acetylcholine receptors. These compounds clearly discriminate between these two types of receptors being more potent inhibitors of the muscarinic receptor with inhibitory constants in the micromole range. (The corresponding values for the nicotinic receptor are in the range of 0.1 mM.) However, the inhibitory potency in the binding assay does not correlate with the ED50 values obtained against soman in mice. The site of antidotal action therefore appears not to be the nicotinic acetylcholine receptor. Binding to the muscarinic receptors may partially contribute to the effects against soman in vivo.
ESTHER : Kuhnen-Clausen_1983_Arch.Toxicol_54_171
PubMedSearch : Kuhnen-Clausen_1983_Arch.Toxicol_54_171
PubMedID: 6661028

Title : Membranes rich in acetylcholine receptor: characterization and reconstitution to excitable membranes from exogenous lipids - Schiebler_1978_Eur.J.Biochem_85_55
Author(s) : Schiebler W , Hucho F
Ref : European Journal of Biochemistry , 85 :55 , 1978
Abstract : Characterization of acetylcholine-receptor-enriched membranes from Torpedo californica electric tissue by negative-staining electron-microscopy and by lipid analysis is described. The protein/lipid ratio is 70%/30%. The lipids consist of 70% phospholipids (46% phosphatidylcholine, 31% phosphatidylethanolamine, 14% phosphatidylserine, 7% sphingomyelin, 2% phosphatidylinositol of the phospholipids determined) and 20% cholesterol. The acetylcholinesterase-enriched membranes show a similar composition. The only differences are a lower protein/lipid ratio (45%/55%) and a lower phosphatidylcholine/sphingomyelin ratio of 39%/14% as compared to 46%/7% for the receptor-enriched membranes. A method of preparing single-walled phosphatidylcholine vesicles by gel filtration on Sephadex G50 according to Brunner et al. (Biochem. Biophys. Acta, 455, 322--331, 1976) is used to recombine the lipid-depleted receptor complex with artificial lipid vesicles. Starting from a lipid mixture of 46% phosphatidylcholine, 31% phosphatidylethanolamine, 14% phosphatidylserine, 7% sphingomyelin, 2% phosphatidylinositol and 15% cholesterol we obtained vesicles associated with the acetylcholine receptor complex. These receptor vesicles are chemically excitable by 10 micrometer carbamoylcholine as measured by efflux of 22Na+ from the vesicles. The excitability is blocked by preincubation with 0.5 mM alpha-toxin from Naja naja siamensis venom and by reduction with 5 mM dithioerythritol.
ESTHER : Schiebler_1978_Eur.J.Biochem_85_55
PubMedSearch : Schiebler_1978_Eur.J.Biochem_85_55
PubMedID: 639824

Title : Azidophenantridinium compounds as photoaffinity labels of cholinergic proteins - Stengelin_1978_Biochim.Biophys.Acta_542_107
Author(s) : Stengelin S , Walther C , Hucho F
Ref : Biochimica & Biophysica Acta , 542 :107 , 1978
Abstract : The synthesis of diazidopropidium and diazidoethidium is described. The applicability of these compounds as photoaffinity labels for cholinergic proteins has been investigated: diazidopropidium inhibits neuromuscular transmission. This inhibition is reversible if the compound is applied in the dark but becomes irreversible after irradiation with white light. Inhibition is accompanied by a disappearance of miniature endplate potentials. Electrophysiological analysis of this effect indicates that diazidopropidium acts postsynaptically by blocking the acetylcholine receptors. At the molecular level the action of diazidopropidium and diazidoethidium on acetylcholinesterase has been investigated: both compounds appear to bind to a peripheral acetylcholine binding site of this enzyme. Binding of 125I-labeled alpha-neurotoxin from Naja naja siamensis to purified membranes from Torpedo californica electric tissue rich in acetylcholine receptors is diminished after incubation and irradiation with diazidopropidium. About half of the toxin binding sites appear to be blocked by the photoaffinity label.
ESTHER : Stengelin_1978_Biochim.Biophys.Acta_542_107
PubMedSearch : Stengelin_1978_Biochim.Biophys.Acta_542_107
PubMedID: 208646

Title : Selective labeling of anionic binding sites of the acetylcholinesterase from Torpedo californica with a photoaffinity label -
Author(s) : Layer PG , Kiefer HR , Hucho F
Ref : Molecular Pharmacology , 12 :958 , 1976
PubMedID: 1004492