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141.
Peter Sarnow Patrick Hearing Carl W. Anderson Nancy Reich Arnold J. Levine 《Journal of molecular biology》1982,162(3):565-583
Antisera from some hamsters bearing adenovirus-induced tumors contain antibodies to an 11,000 Mr adenovirus-induced protein. In adenovirus-infected HeLa cells, this early viral protein was specifically associated with the nuclear matrix fraction. After two-dimensional gel electrophoresis, two forms of the 11,000 Mr protein at pI 5.6 and pI 5.4 were found. Only the pI 5.4 form of this protein was associated with the nuclear matrix fraction. Adenoviruses from groups A, B, C, D and E all produced an early viral protein (10,000 to 12,000 Mr) that reacted with group C antibody to the 11,000 Mr protein. To date, this is the only known early viral protein that is immunologically conserved in all of the human adenovirus groups.The positions of two methionine and seven leucine residues were determined by sequencing the first 35 amino acids from the N terminus of the adenovirus serotype 2 group C 11,000 Mr protein. The positions of these amino acid residues were compared to the adenovirus serotype 2 nucleotide sequence, which uniquely localized the structural gene of the 11,000 Mr protein to region E4, subregion 3 in type 2 adenovirus. A frameshift mutant, which contained a deletion of one base-pair in the structural gene of the 11,000 Mr protein, was isolated and mapped by marker rescue and nucleotide sequence analysis. This mutant failed to produce immunologically detectable 11,000 Mr protein. The mutant had a viable phenotype, producing normal levels of infectious virus in both HeLa cells and WI38 cells in culture. These experiments identify the first adenovirus early region 4 protein detected in virus-infected cells. 相似文献
142.
S.B. Jakowlew P. Khandekar K. Datta H.-H. Arnold S.K. Narula M.A.Q. Siddiqui 《Journal of molecular biology》1982,156(3):673-682
A recombinant DNA plasmid, pMHC8, that contains gene sequences for embryonic chick cardiac myosin heavy chain was constructed, identified and characterized. The identity of the clone was established by hybridization with labeled probes that afford screening of MHC22 with high specificity, by inhibition of MHC synthesis in the in vitro hybrid-arrested translation assay, and by tissue-specific hybridization of labeled pMHC8 DNA to MHC messenger RNA.The pMHC8 DNA probe is highly specific for chick heart muscle tissue, since it hybridized poorly to chick skeletal muscle RNA and did not detectably hybridize to adult rat heart RNA. Upon screening the embryonic chick heart cells in culture, no detectable level of MHC mRNA was observed in dividing myoblasts, but the mRNA appeared in differentiated cardiac myocytes paralleling morphogenetic changes in the embryonic cells. 相似文献
143.
Fritz Schöffl Walter Arnold Alfred Pühler Josef Altenbuchner Rüdiger Schmitt 《Molecular & general genetics : MGG》1981,181(1):87-94
Summary The 10.7 kilobase (kb) tetracycline resistance transposons Tn1721 and Tn1771, isolated from disparate sources, are completely homologous on the basis of heteroduplex analyses. Both transposable elements are capable of forming multiple duplications of a 5.3 kb portion encompassing the resistance genes (tet region). A model accounting for both, recA-independent translocation and recA-dependent amplification, postulates two direct and one inverted repeat as essential constituents of the transposons. DNA sequence analyses of Tn1721 and Tn1771 have substantiated this model. They demonstrated three identical 38 base pair repeats identically in both transposons dividing them into a minor transposon and a tet region. Identical sequences of at least 87 base pairs providing recombination hot spots for gene duplication have been found at the ends of the repetitious tet region. Translocation of Tn1721 and Tn1771 generates five base pair direct repeats at the respective sites of insertion. On the basis of the heteroduplex molecules and sequences analyzed the two transposons are identical.To Professor Wolfram Heumann on the occasion of his 65th birthday 相似文献
144.
Giovanni Spinelli Marialuisa Melli Eva Arnold Caterina Casano Fabrizio Gianguzza Mirella Ciaccio 《Journal of molecular biology》1980,139(2):111-122
Sea urchin RNA extracted from early and mesenchyme blastula embryos and oocytes and fractionated on denaturing sucrose density gradients, was hybridized with histone DNA recombinants of Psammechinus miliaris (clone λh22) and of Paracentrotus lividus (clone pPH70). Histone sequences are found in the 9 S and larger than 9 S regions of the formamide/sucrose density gradients. The melting of the RNA-DNA duplexes obtained by hybridization of polysomal and high molecular weight RNA of embryos of P. lividus at the stage of early blastula, suggests a degree of heterogeneity in the high Mr RNA. The high Mr RNA contains at least four of the five histone gene sequences covalently linked. 相似文献
145.
A bound form of creatine kinase associated with brain particulate was characterized by isoelectric focusing, antigenicity and chromatography and compared to muscle (MM), brain (BB), and heart mitochondrial isoenzymes. On partial purification and isoelectric focusing, the solubilized enzyme has a pl of 7.3, similar to the pl of muscle creatine kinase MM, pl 6.8, but different from brain creatine kinase BB, which precipitates on isoelectric focusing in sucrose or glycerol stabilized media at its calculated pl of 5.6. Gel filtration chromatography of deoxycholate solubilized particulate creatine kinase on Sephadex Gl50 reveals an estimated molecular weight of approximately 80,000 daltons. The brain particulate enzyme is antigenically distinct from both muscle and rat heart mitochondrial creatine kinase isoenzymes but has antigenic similarity with soluble cytoplasmic brain BB. The situation may be analogous to that found with rat heart mitochondria and rat heart cytoplasmic isoenzymes which we have shown to exhibit antigenic similarity even though differences in electrophoretic and amino acid composition have been demonstrated; however, the confident determination that the particulate enzyme is a separate isoenzyme will have to await amino acid analysis. 相似文献
146.
Don J. Brenner Jan Ursing Hervé Bercovier Arnold G. Steigerwalt G. Richard Fanning Jean Michel Alonso H. H. Mollaret 《Current microbiology》1980,4(4):195-200
Yersinia enterocolitica andY. enterocolitica-like strains were characterized by DNA relatedness. These strains formed four distinct DNA relatedness groups: (i) the 5
classical biotypes ofY. enterocolitica sensu stricto as designated by Wauters; (ii) strains that are rhamnose positive and also positive in tests for melibiose, α-methyl-d-glucoside, raffinose, and Simmons' citrate; (iii) strains that are rhamnose positive but negative in tests for melibiose,
α-methyl-d-glucoside, and raffinose; (iv) sucrose-negative, Voges-Proskauer-negative, trehalose-positive strains. 相似文献
147.
148.
The purpose of this study was to examine the effect of exogenous adrenocorticotropin (ACTH), administered to gilts during early stages of gestation, upon fetal survival and various maternal and conceptus parameters. Forty-eight gilts of approximately 6-7 months of age were bred by means of artificial insemination after detection of the second estrus and randomly allotted to one of 12 treatment-period groups. Treatment consisted of a daily intramuscular injection of 0, 40 or 80 U.S.P. units of a long acting ACTH preparation for a period of five days. The injection periods were 1-5, 6-10, 11-15 or 16-20 days of gestation with day one corresponding to 48 hours post-estrus detection. All gilts were slaughtered at approximately 37 days of gestation. Forty-two of the 48 inseminated gilts conceived. Conception rate was not different (P>.10) among the 12 treatment-period combinations. Percent fetal survival was greater (P<.09) in gilts receiving 80 U.S.P. units of ACTH (82 +/- 4.3%; X +/- SEM ) than in gilts receiving 40 U.S.P. units of ACTH (68.8 +/- 4.5%). The percent fetal survival in the control group (71.7 +/- 3.9%) was not different (P>.10) from either of the two ACTH treatment groups. A significant (P<.05) treatment by period interaction for percent fetal survival was observed. The lowest percent fetal survival (48.0 +/- 9.0%) was observed in gilts receiving 40 U.S.P. units of ACTH on day 11-15 of gestation. No significant (P>.10) differences were detected among the 12 treatment-period combinations for any of the maternal or conceptus parameters measured. 相似文献
149.
The effect of superoxide dismutases from five species upon phospholipid bilayers has been investigated. The uptake by egg phosphatidylcholine bilayers of the holo and apo forms of bovine superoxide dismutase increases with enzyme concentration and only a fraction of each is removed by treatment with trypsin. These uptake data indicate that both forms of the enzyme associate with and are embedded within lipid bilayers. From the spectrum of the spin label 2-(3-carboxypropyl)-4,4-dimethyl-2-tridecyl-3-oxazolidinyloxyl, the binding of superoxide dismutase to egg phosphatidylcholine bilayers can be shown to disorder the lipid packing. The disordering by the bovine holoenzyme is small but increases with increasing enzyme concentration and period of incubation. The disordering effects of the apoenzyme are much larger and are reversible by Cu2+, Zn2+ reconstitution of the apoenzyme. The disordering effect of the apoenzyme is further confirmed by differential scanning calorimetry. The gel to liquid crystalline phase transition of egg phosphatidylcholine is lowered 7 degrees C by 25% by weight apo-superoxide dismutase to lipid. Human, dog, swordfish and yeast superoxide dismutases also disorder, and to a greater extent than the bovine enzyme. The greatest perturbation is produced by yeast superoxide dismutase; a 20% decrease in the order parameter by 50% by weight enzyme to lipid. 相似文献
150.