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V Müller

Publications and source records attributed to V Müller.

At least 145 records · Page 8Linked to original sources
PubMed1986

Utilization of Methanol plus Hydrogen by Methanosarcina barkeri for Methanogenesis and Growth.

Methanosarcina barkeri grew on methanol plus H(2). Both substrates were consumed in equimolar amounts. Growth was strictly dependent on the presence of acetate, which was required for the biosynthesis of cellular constituents. Only about 0.4% of the methane produced originated from acetate. By using deuterated methanol, it was demonstrated that methanogenesis from this compound under H(2) did not occur via oxidation of methanol to CO(2) and subsequent reduction but by direct reduction with H(2). Growth yields with methanol plus H(2) and with methanol alone were not significantly different: 2.8 g of cells per mol of methanol in mineral medium and 4.6 g of cells per mol of methanol in complex medium, respectively. Growth of M. barkeri on methanol plus H(2) depended strictly on the presence of sodium ions in the medium. In the presence of 50 mM K the K(s) for Na was 5 mM.

Journal Article↗
PubMed1986

[Atomic absorption spectrophotometric determination of zinc in granulocytes, lymphocytes and serum of untreated and alloxan diabetic rats].

Atomic absorptions spectrophotometric determinations of zinc in serum, granulocytes and lymphocytes after separation of blood samples of normal and alloxan diabetic rats, control persons and diabetics by the method of Böyum verify our conception that changes of metal content and structure in cells by metal chelating agents are induced primary by chemical and secondary by disturbed carbohydrate metabolism conditions. Alloxan (200 mg/kg of body weight, intraperitoneally) destroys selectively not only the B-cells of the islets of Langerhans but also the granulocytes, while the lymphocytes are not changed in respect to the zinc content and cell count. The lymphocytes of diabetics are unchanged in the zinc content, too. The earlier opinion that leucocytes belong to the slowly exchanging zinc compartments of the blood is only exact for lymphocytes, whereas the granulocytes and the serum, corresponding to an exchange pool of metal ions, may play a more important role in the transport system of the zinc.

Animals↗
PubMed1985

Characterization of gP85gag as an antigen recognized by Moloney leukemia virus-specific cytolytic T cell clones that function in vivo.

The gag membrane protein gP85gag, encoded by Moloney murine leukemia virus (M-MLV), was identified as a target molecule recognized by Moloney murine sarcoma virus--M-MLV (M-MSV--M-MLV)-specific cytolytic T lymphocyte (CTL) clones. Target cells infected with Ab-X-MLV, an M-MLV-derived mutant virus not encoding gP85gag, were not lysed by the CTL clones. The same CTL clones were shown previously to induce the destruction of M-MLV-induced tumor cells in the peritoneal cavity. We have now characterized CTL-resistant antigen-loss tumor cell variants that have lost the surface antigen, but which retain transcriptionally silent M-MLV genomes. A cloned antigen-loss variant that reverted in vitro to the CTL-susceptible phenotype reexpressed M-MLV genomes that had undergone an insertion event in the region of the viral DNA coding for the gag membrane protein. Intravenous injection of virus-specific CTL clones inhibited tumor formation in mice injected subcutaneously with M-MSV--M-MLV.

Animals↗
PubMed1985

Sodium ions and an energized membrane required by Methanosarcina barkeri for the oxidation of methanol to the level of formaldehyde.

Methanogenesis from methanol by cell suspensions of Methanosarcina barkeri was inhibited by the uncoupler tetrachlorosalicylanilide. This inhibition was reversed by the addition of formaldehyde. 14C labeling experiments revealed that methanol served exclusively as the electron acceptor, whereas formaldehyde was mainly oxidized to CO2 under these conditions. These data support the hypothesis (M. Blaut and G. Gottschalk, Eur. J. Biochem. 141: 217-222, 1984) that the first step in methanol oxidation depends on the proton motive force or a product thereof. Cell extracts of M. barkeri converted methanol and formaldehyde to methane under an H2 atmosphere. Under an N2 atmosphere, however, formaldehyde was disproportionated to CH4 and CO2, whereas methanol was metabolized to a very small extent only, irrespective of the presence of ATP. It was concluded that cell extracts of M. barkeri are not able to oxidize methanol. In further experiments, the sodium dependence of methanogenesis and ATP formation by whole cells was investigated. Methane formation from methanol alone and the corresponding increase in the intracellular ATP content were strictly dependent on Na+. If, in contrast, methanol was utilized together with H2, methane and ATP were synthesized in the absence of Na+. The same is true for the disproportionation of formaldehyde to methane and carbon dioxide. From these experiments, it is concluded that in M. barkeri, Na+ is involved not in the process of ATP synthesis but in the first step of methanol oxidation.

Adenosine Triphosphate↗
PubMed1985

Sequences upstream of c-mos(rat) that block RNA accumulation in mouse cells do not inhibit in vitro transcription.

An unusual feature of the c-mos oncogene is the lack of expression in mouse tissues. Recombinant plasmids that contain the strong adenovirus late promoter and different amounts of cellular DNA 5' to c-mos(rat) were constructed and tested in transfection and transcription assays. The cellular sequences inhibit RNA accumulation in mouse but not human cells and do not inhibit in vitro transcription of the plasmid DNAs.

Adenoviridae↗
PubMed1985

Differential transformation of C3H10T1/2 cells by v-mos: sequential expression of transformation parameters.

Extremely small quantities of the product of the transforming gene v-mos of Moloney murine sarcoma virus are able to efficiently transform cells. Recent data indicate the existence of a threshold level for v-mos transformation of NIH3T3 cells. Using mouse mammary tumor virus long terminal repeat sequences or hybrid promoters consisting of mouse mammary tumor virus and Moloney murine sarcoma virus long terminal repeat elements to express v-mos in C3H10T1/2 cells, we established cell lines representing different stages of morphological transformation in vitro. The threshold level for v-mos transformation was considerably lower than that for NIH3T3 cells, because no treatment with dexamethasone or primary selection other than transformation was necessary during standard transfection procedures. Using the cell lines mentioned we established an association of the level of v-mos expression with the transformation parameters examined, but not with p53 levels. Furthermore, the characterization of the different promoters showed (i) that the distal binding site confers hormone responsiveness to Moloney murine sarcoma virus promoter elements and (ii) that artifactual transcription initiation sites can be detected in mouse mammary tumor virus-Moloney murine sarcoma virus hybrid promoters which are, however, not regulated by the hormone.

Animals↗
PubMed1985

[Results of immunosuppressive therapy of chronic glomerulonephritis in 400 patients].

For the judgment of the success of the immunosuppressive therapy of chronic glomerulonephritis 400 patients (242 males and 158 females) at an average age of 31.2 years were examined after an average duration of treatment of 31.9 months. Apart from the renal function (serum creatinine), the histological and immunohistological form of the glomerulonephritis for the valuation further clinico-paraclinical data were taken into consideration: proteinuria, nephrotic syndrome, arterial hypertension and the combination of nephrotic syndrome and arterial hypertension. At the beginning of the treatment 293 of 400 patients (73.2%) had a normal renal function, 107 of 400 patients (26.8%) were initially renal-insufficient. 16 of 400 patients (4.0%) had additionally a pyelonephritis and 12 of 400 patients (3.0%) had a lupus nephritis. 27 of 400 patients (6.9%) developed a terminal renal insufficiency after an average duration of observation of 40.5 months. Complications caused by therapy were registered in 104 of 400 patients (26.0%). Recommendations for the present therapy of chronic glomerulonephritis are formulated.

Adolescent↗
PubMed1984

Interspecific differentiation of Trypanosoma cruzi, Trypanosoma conorhini and Trypanosoma rangeli by lectins in combination with complement lysis.

Four-day-old epimastigote culture forms of Trypanosoma cruzi, Trypanosoma rangeli and Trypanosoma conorhini were tested with 21 lectins. Furthermore T. conorhini was incubated with the following sera: rat, Wistar HAN, germ free; normal fresh hen, rat and human serum. T. rangeli was agglutinated only by the D-mannose specific lectins from Canavalia ensiformis and Pisum sativum. T. cruzi and T. conorhini could be distinguished by the lectin from Tridacna crocea. The epimastigote culture forms of T. conorhini were not lysed by normal fresh rat, hen and human sera. Therefore, T. cruzi, T. conorhini and T. rangeli can be distinguished interspecifically by lectins and by the different lytic effect of rat, hen and human sera. It is possible to separate each of the species by complement lysis. The lysis-resistant species can be cultivated for further examinations.

Agglutination Tests↗
PubMed1983

[Congenital bullous erythroderma ichthyosiforme in 4 generations. Histological, electronmicroscopy findings and HLA typing].

Epidermolytic hyperkeratosis is a rare hereditary disease characterized by change of the dermatological signs with advancing age of the patients. At birth as well as during childhood, epidermolysis and blister formation are found; later the general picture of the disease presents horny hystrix-like lesions especially on the flexor parts of the extremities. Bullae become rare in adult life, vulnerability, however, remains. Here we report on 21 patients out of a 38-member family showing the above mentioned clinical findings. Electron-optical as well as histological studies are presented. For the first time HLA-type is reported.

Adult↗
PubMed1982

Characterization of the mRNA and cloned cDNA specifying the third component of mouse complement.

Eighteen cDNA clones containing inserts specific for the third component of complement (C3) have been derived from high molecular weight mouse liver mRNA. The inserts span 4,600 nucleotides of the C3 coding sequence, including the 3' end of C3 mRNA. The length of C3 mRNA was determined to be 5,100 +/- 200 nucleotides, including a poly(A)-containing tail of mean length 170 nucleotides. From cDNA sequence analysis of the 5'-proximal region of C3 mRNA, the NH2-terminal amino acid sequence of the mature C3 beta chain was predicted to be Ile-Pro-Met-Tyr-Ser-Ile-Ile-Thr-Pro-Asn-Val-Leu-Arg-Leu-Glu. This sequence is in good agreement with the reported amino acid sequences of human and guinea pig C3 beta chains. These data position the C3 beta subunit to the NH2-terminal portion of the precursor C3 molecule (pro-C3) and establish the order of subunits in pro-C3 to be NH2-beta-alpha-COOH. In addition, the cDNA sequence indicates that an NH2-terminal extension peptide precedes the beta chain in pro-C3. The amino acid sequence of the mouse C3a fragment and its flanking regions was determined. The data indicate the presence of four arginine residues located between the COOH terminus of the C3 beta and the NH2 terminus of the C3 alpha subunits in pro-C3. The coding sequences of the amino acids that constitute the internal thioester domain in C3 were determined. Unexpectedly, the glutamyl residue that has been shown to participate in the thioester bond in native C3 was found to be encoded as a glutamine.

Animals↗