TY - JOUR A1 - McCarthy, J. E. A1 - Sebald, Walter A1 - Gross, G. A1 - Lammers, R. T1 - Enhancement of translational efficiency by the Escherichia coli atpE translational initiation region: its fusion with two human genes N2 - No abstract available KW - Biochemie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62626 ER - TY - JOUR A1 - Gabellini, N. A1 - Sebald, Walter T1 - Nucleotide sequence and transcription of the fbc operon from Rhodopseudomonas sphaeroides. Evaluation of the deduced amino acid sequences of the FeS protein, cytochrome b and cytochrome c\(_1\) N2 - No abstract available KW - Biochemie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62615 ER - TY - JOUR A1 - Hoppe, J. A1 - Sebald, Walter T1 - Topological studies suggest that the pathway of the protons through F\(_0\) is provided by amino acid residues accessible from the lipid phase N2 - The structure of the F0 part of ATP synthases from E. coli and Neurospora crassa was analyzed by hydrophobic surface labeling with [125I]TID. In the E. co/i F0 all three subunits were freely accessible to the reagent, suggesting that these subunits are independently integrated in the membrane. Labeted amino acid residues were identified by Edman degradation of the dicyclohexylcarbodiimide binding (DCCD) proteins from E. coli and Neurospora crassa. The very similar patterns obtained with the two homologaus proteins suggested the existence of tightly packed cx-helices. The oligomeric structure of the DCCD binding protein appeared to be very rigid since little, if any, change in the labeling patternwas observed upon addition of oligomycin or DCCD to membranes from Neurospora crassa. When membrancs were pretrcated with DCCD prior to the reaction with [125I]TID an additionally labeled amino acid appeared at the position of Glu·65 which binds DCCD covalently, indicating the Jocation of this inhibitor on the outside of the oligomer. It is suggested that proton conduction occurs at the surface of the oligomer of the DCCD binding protein. Possibly this oligomer rotates against the subunit a or b and thus enables proton translocation. Conserved residues in subunit a, probably located in the Iipid bilayer, might participate in the pro· ton translocation mechanism. N2 - La structure de la partie F0 de l'ATP synthase a ete analysee au moyen de marquage par /e reactif hydrophobe TJD[125 I]. Les trois sous-unites de E. coli F0 sont accessibles au reactif ce qui semble indiquer que ces sous-unites sont integrees dans Ia membrane defaron independante. Les amino-acides marques ont ete identifies par Ia degradation d'Edman des profeines d'E. coli et de Neurospora associees au dicyclohexylcarbodiimide (DCCD). L 'analogie des courbes obtenues pour /es deux proteines homologues suggere l'existence d'a-helices rangees de faron serree. La structure oligomerique de Ia proreine associee au DCCD semble etre tres rigide puisque pratiquement aucun changement dans /e marquage n 'a ete observe par addition d'oligomycine ou de DCCD aux membranes de Neurospora crassa. Quand /es membranes sont traitees avec /e DCCD avant Ia reaction avec TJD[125 I], un amino-acide additionnellement marque apparait a Ia position Glu·65 et forme avec le DCCD une Iiaison covalente. Ce dernier resu/tat indique Ia localisation de cet inhibiteur a /'exterieur de J'oligo· mere. II semble donc que Ia conduction des protons ait lieu a Ia surface de /'oligomere de Ia proteine associee au DCCD. II serait possib/e que l'o/igomere se retourne contre Ia sous-unite a ou b, permettunt de ce fait Ia translocation des protons. Les residus conserves de Ia sous-unite a, probab/ement Jocalises dans Ia double couche lipidique, pourraient participer au mecanisme de translocation des protons. KW - Biochemie KW - conduction de protons KW - proteines membranaires KW - carbenes KW - proton conduction KW - membrane proteins KW - carbenes Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62602 ER - TY - JOUR A1 - Hoppe, J. A1 - Gatti, D. A1 - Weber, H. A1 - Sebald, Walter T1 - Labeling of individual amino acid residues in the membrane-embedded F\(_0\) part of the F\(_1\) F\(_0\) ATP synthase from Neurospora crassa. Influence of oligomycin and dicyclohexylcarbodiimide N2 - Three F0 subunits and the F\(_1\) subunit P of the ATP synthase from Neurospora crassa were labeled with the lipophilic photoactivatable reagent 3-(trifluoromethyl)-3-(m-[\(^{125}\)I]iodophenyl)diazirine ([\(^{125}\)I]TID). In the proteolipid subunit which was the most heavily labeled polypeptide labeling was confmed to five residues at the NH2-terminus and five residues at the C-terminus ofthe protein. Labeling occurred at similar positions compared with the homologaus protein (subunit c) in the ATP synthase from Escherichia coli, indicating a similar structure of the proteolipid subunits in their respective organisms. The inhibitors oligomycin and dicyclohexylcarbodiimide did not change the pattern of accessible surface residues in the proteolipid, suggesting that neither inhibitor induces gross conformational changes. However, in the presence of oligomycin, the extent oflabeling in some residues was reduced. Apparently, these residues provide part of the binding site for the inhibitor. After reaction with dicyclohexylcarbodiimide an additional labeled amino acid was found at position 65 corresponding to the invariant carbodümide-binding glutamic acid. These results and previous observations indicate that the carboxyl side chain of Glu-65 is located at the protein-lipid interphase. The idea is discussed that proton translocation occurs at the interphase between different types if F\(_0\) subunits. Dicyclohexylcarbodiimide or oligomycin might disturb this essential interaction between the F\(_0\) subunits. KW - Biochemie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62598 ER - TY - JOUR A1 - Weich, H. A. A1 - Sebald, Walter A1 - Schairer, H. U. A1 - Hoppe, J. T1 - The human osteosarcoma cell line U-2 OS expresses a 3.8 kilobase mRNA which codes for the sequence of the PDGF-B chain N2 - A cDNA clone of about 2500 basepairswas prepared from the human osteosarcoma cellline U-2 OS by hybridizing with a v-sis probe. Sequence analysis showed that this cDNA contains the coding region for the PDGF-B chain. Here we report that the mitogen secreted by these osteosarcoma cells contains the PDGF-B chain and is probably a homodimer of two B-chains. KW - Biochemie KW - Platelet-derived growthfactor KW - cDNA KW - Oncogene KW - Tumor cell Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62588 ER - TY - JOUR A1 - Barnekow, Angelika A1 - Gessler, Manfred T1 - Activation of the pp60\(^{c-src}\) kinase during differentiation of monomyelocytic cells in vitro N2 - Tbe proto-oncogene c-src, the cellular homolog of the Rous sarcoma virus (RSV) transforming gene v-src, is expressed in a tissue-specific and age-dependent manner. Its physiological function, although still unknown, appears to be more closely related to differentiation processes than to proliferation processes. To obtain more information about the physiological role of the c-src gene in cells, we have studied differentiation-dependent alterations using the human HL-60 leukaemia cell line as a model system. Induction of monocytic and granulocytic differentiation of HL-60 cells by 12-0-tetradecanoylphorbol-13-acetate (TPA) and dimethylsulfoxide (DMSO) is associated with an activation of the pp60c-src tyrosine kinase, but not with increased c-src gene expression. Control experiments exclude an interaction of TPA and DMSO themselves with the pp60c-src kinase. KW - Biochemie KW - c-src KW - differentiation KW - protein tyrosine kinase KW - protooncogene Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59278 ER -