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Comparative 16S rRNA oligonucleotide analyses and murein types of round-spore-forming bacilli and non-spore-forming relatives 总被引:6,自引:0,他引:6
E Stackebrandt W Ludwig M Weizenegger S Dorn T J McGill G E Fox C R Woese W Schubert K H Schleifer 《Journal of general microbiology》1987,133(9):2523-2529
The phylogenetic incoherency of the genus Bacillus as presently described is demonstrated by analysis of both published and new data from comparative 16S rRNA cataloguing of nine Bacillus species and a number of related non-Bacillus taxa, i.e. Caryophanon latum, Filibacter limicola and Planococcus citreus. While the ellipsoidal-spore-forming bacilli, e.g. B. subtilis and allied species, formed a coherent cluster, the round-spore-forming bacilli showed a higher degree of relationship to the non-spore-forming organisms than these bacilli show among each other. Thus B. sphaericus clustered with C. latum, B. globisporus grouped with F. limicola, B. pasteurii with Sporosarcina ureae, and 'B. aminovorans' with P. citreus, respectively. These organisms formed two related subclusters which, in their phylogenetic depth, are comparable to that of the B. subtilis subline. With the exception of 'B. aminovorans', the 16S rRNA phylogeny was entirely consistent with the distribution of murein types. Even more distantly related to and grouping outside the main Bacillus cluster was B. stearothermophilus, which displayed a moderate relationship to Thermoactinomyces vulgaris. Taxonomic problems arising from the new insights into the intrageneric relationships of Bacillus are discussed. 相似文献
4.
G W Dorn 《Biochemical and biophysical research communications》1989,163(1):183-188
To further characterize the human thromboxane A2 (TXA2)/prostaglandin H2 (PGH2) receptor, preparative isoelectric focusing (IEF) was performed on solubilized platelet membranes. TXA2/PGH2 receptors, assayed by specific binding of the TXA2/PGH2 antagonist [125I]PTA-OH, were electrofocused at pH 5.6. Scatchard analysis of IEF fraction pH 5.6 revealed a 180-fold concentration of TXA2/PGH2 receptors (Bmax = 3650 +/- 228 pM/mg focused, 19 +/- 4 pM/mg unfocused) with no change in binding affinity (Kd = 47 +/- 7 nM focused, 36 +/- 14 nM unfocused). SDS-polyacrylamide gel electrophoresis of photoaffinity-labelled electrofocused receptors revealed concentration of specifically labelled proteins having molecular masses of 49,000 and 27,000 Daltons. These results suggest that the human platelet TXA2/PGH2 receptor has a pI of 5.6, molecular mass of 49,000 Daltons, and may exist as a dimer. Preparative IEF should prove useful in the eventual purification of this receptor. 相似文献
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Studies on protein kinases involved in regulation of nucleocytoplasmic mRNA transport. 总被引:3,自引:0,他引:3 下载免费PDF全文
H C Schr?der M Rottmann R Wenger M Bachmann A Dorn W E Müller 《The Biochemical journal》1988,252(3):777-790
The rate of energy-dependent nucleoside triphosphatase (NTPase)-mediated nucleocytoplasmic translocation of poly(A)-containing mRNA [poly(A)+mRNA] across the nuclear envelope is thought to be regulated by poly(A)-sensitive phosphorylation and dephosphorylation of nuclear-envelope protein. Studying the phosphorylation-related inhibition of the NTPase, we found that phosphorylation of one polypeptide of rat liver envelopes by endogenous NI- and NII-like protein kinase was particularly sensitive to poly(A). This polypeptide (106 kDa) was also phosphorylated by nuclear-envelope-bound Ca2+-activated and phospholipid-dependent protein kinase (protein kinase C). Activation of kinase C by tumour-promoting phorbol esters resulted in inhibition of nuclear-envelope NTPase activity and in a concomitant decrease of mRNA (actin) efflux rate from isolated rat liver nuclei. Protein kinase C, but not nuclear envelope NI-like or NII-like protein kinase, was found to be solubilized from the envelope by Triton X-100, whereas the presumable poly(A)-binding site [the 106 kDa polypeptide, representing the putative carrier for poly(A)+mRNA transport] remained bound to this structure. RNA efflux from detergent-treated nuclei lost its susceptibility to phorbol esters. Addition of purified protein kinase C to these nuclei restored the effect of the tumour promoters. Protein kinase C was found to bind also to isolated rat liver nuclear matrices in the absence but not in the presence of ATP. The NII-like nuclear-envelope protein kinase co-purified together with the 106 kDa polypeptide which specifically binds to poly(A) in an ATP-labile linkage. 相似文献
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Isolation and characterization of a large,neurite-associated glycoconjugate from neuroblastoma cells 下载免费PDF全文
A high molecular weight glycoconjugate has been isolated from neurite-producing neuronal tumor cells in culture and has been designated as I(0) based on its elution characteristics in gel filtration chromatography. This molecule cannot be found in a variety of nonneuronal cells. I(0) is found in the substratum-attached material or cell fraction of neurite-producing neuroblastoma cells, depending upon culture conditions. It is found in the substratum-bound fraction of B104 rat neuroblastoma cells during serum starvation and in the EGTA-detached cell fraction of B104 cells grown in chemically defined N2 medium. It occurs only in the cell fraction of the human neuroblastoma line Platt. Examination of behavioral variants of the B104 rat line further strengthens the association of I(0) with neurite production; the constitutive neurite-producing E(R)B9 variant contains I(0) while the non-neurite-producing E(R)A11 variant does not. I(0) is large, eluting in the void volume of sepharose-CL2B columns. Radioiodination of intact cells with lactoperoxidase shows I(0) to be a cell surface component. Metabolic radiolabeling studies show that it contains a high proportion of polysaccharide to protein, does not contain mannose, and is unsulfated. Alkaline borohydride reduction release two size classes of large polysaccharide chain. The alkaline reduction results, along with the mannose incorporation studies, show the presence of O-glycosidic linkages and few, if any, N-linkages. Resistance to nitrous acid deamination, insensitivity to glycosaminoglycan lyases, and the absence of sulfation, indicate that I(0) does not contain the glycosaminoglycans hyaluronic acid, chondroitin-, dermatan-, or heparin- sulfates. Affinity column chromatography reveals high binding affinity of I(0) to polyornithine and no binding to gelatin (collagen) or the glycosaminoglycans hyaluronate and heparin. These studies describe a unique high molecular weight glycoconjugate on the surface of neurite-producing neuroblastoma cell lines from two species. 相似文献
8.
August Dorn 《Zoomorphology》1972,71(1):52-104
The differentiation of the endocrine glands in the embryo of Oncopeltus fasciatus is described. The function of these glands can be correlated with the embryonic moults. The nuclei of some tissues already become polyploid in the embryo. It is discussed whether the endomitotic growth is dependent upon the function of the endocrine glands.
Abkürzungen in den Abbildungen A Ca Anlage des Corpus allatum - A Cc Anlage des Corpus cardiacum - A Maxd Anlage der Maxillendrüse - A Meth Anhang des Mesothorax - A Mth Anhang des Metathorax - A Pl Anlage des-Pleuropodiums - A Prd Anlage der Prothoraxdriise - A Pth Anhang des Prothorax - A Spd Anlage der Speicheldrüse - Am Amnion - Ant Antenne - Ao Aorta - Blz Blutzelle - Ca Corpus allatum - Cc Corpus cardiacum - Cul Cuticulinschicht - Cut Cuticula - Des Desmosom - dl denselayer - Do Dotter - Ent Entoderm - Ep Epidermis - Epk Epidermiskern - Fk Fettkörper - fl Do verflüssigter Dotter - Hyp Hypocerebralganglion - Hz Herzschlauch - Kl Kopflappen - La Labrum - Lab Labium - M Mitteldarm mit verschiedenen Abschnitten (I, II, III und IV) - Mal Malpighisches GefäB - Max Maxille - Md Mandibel - Mes Mesoderm - Mik Mikrovilli - Ms Muskel - Mst Mittelstrang - Nbl Neuroblast - NZ Neurosekretorische Zellen - Oen Oenocyt - Oes Oesophagus - Ogl Oberschlundganglion - p Cut Procuticula - Pcz Pericardialzelle - Pi Pleuropodium - Prd Prothoraxdrüse - Pyl Pylorus - Re Rectum - Rk Riesenkern - S Schlüpfakt - Sal Salivarium - Ser Serosa - Sg Segmentgrenze - Spd Speicholdrüse (I = vorderer Lappen, II = scitlicher Lappen, III = hinterer Lappen, IV = akzessorische Drüse und V = Hylus) - Spdg Speicheldrüsengang - St Stechborste - Std Stinkdrüse - Sti Stigma - Stom Stomodaeum - Stt Stechborstentasche - tb E tubuläre Einstülpung des Prothorax - Ugl Unterschlundganglion - V Vakuole Mit Unterstutzung der Deutschen Forschüngsgemcinschaft. 相似文献
Abkürzungen in den Abbildungen A Ca Anlage des Corpus allatum - A Cc Anlage des Corpus cardiacum - A Maxd Anlage der Maxillendrüse - A Meth Anhang des Mesothorax - A Mth Anhang des Metathorax - A Pl Anlage des-Pleuropodiums - A Prd Anlage der Prothoraxdriise - A Pth Anhang des Prothorax - A Spd Anlage der Speicheldrüse - Am Amnion - Ant Antenne - Ao Aorta - Blz Blutzelle - Ca Corpus allatum - Cc Corpus cardiacum - Cul Cuticulinschicht - Cut Cuticula - Des Desmosom - dl denselayer - Do Dotter - Ent Entoderm - Ep Epidermis - Epk Epidermiskern - Fk Fettkörper - fl Do verflüssigter Dotter - Hyp Hypocerebralganglion - Hz Herzschlauch - Kl Kopflappen - La Labrum - Lab Labium - M Mitteldarm mit verschiedenen Abschnitten (I, II, III und IV) - Mal Malpighisches GefäB - Max Maxille - Md Mandibel - Mes Mesoderm - Mik Mikrovilli - Ms Muskel - Mst Mittelstrang - Nbl Neuroblast - NZ Neurosekretorische Zellen - Oen Oenocyt - Oes Oesophagus - Ogl Oberschlundganglion - p Cut Procuticula - Pcz Pericardialzelle - Pi Pleuropodium - Prd Prothoraxdrüse - Pyl Pylorus - Re Rectum - Rk Riesenkern - S Schlüpfakt - Sal Salivarium - Ser Serosa - Sg Segmentgrenze - Spd Speicholdrüse (I = vorderer Lappen, II = scitlicher Lappen, III = hinterer Lappen, IV = akzessorische Drüse und V = Hylus) - Spdg Speicheldrüsengang - St Stechborste - Std Stinkdrüse - Sti Stigma - Stom Stomodaeum - Stt Stechborstentasche - tb E tubuläre Einstülpung des Prothorax - Ugl Unterschlundganglion - V Vakuole Mit Unterstutzung der Deutschen Forschüngsgemcinschaft. 相似文献
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A pseudomonad has been isolated from sewage, which can utilize 3-chlorobenzoic acid as a sole carbon source. In cells grown on benzoate the enzymes of the -ketoadipic acid pathway are present. Considerable enzymic activities for chlorinated substrates were found in benzoate grown cells only for the oxygenation of 3-chlorobenzoate and the dehydrogenation of 3- and 5-chloro-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid. 3-Chlorobenzoate grown cells show additional high activities for the turnover of 3- and 4-chlorocatechols and chloromuconic acids.Abbreviations Used DHB
(-)-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid (derived from the trivial name, dihydrodihydroxybenzoate)
- 3- and 5-Cl-DHB correspondingly
3- and 5-chloro-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid 相似文献
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C. Richard Dorn 《The Western journal of medicine》1967,107(6):481-489
The principles of epidemiology are applicable to the study of the distribution and determinants of cancer in both human and animal populations. There are many examples of epidemiologic factors (host, environment, agent and time) related to cancer in animals. Certain host characteristics such as age, sex and breed are related to risk of developing cancer. Some environmental influences are illustrated by differences in the geographical distribution of certain types of animal cancer.Aggregations of cancer cases have been reported in herds, families and households. However, the usual distribution of cases in a population does not resemble epidemics typical of infectious diseases. Several factors (radiological, chemical, dietary, parasitic, mechanical, genetic and viral) have been identified as influences that affect the development of animal tumors.Animal species that have been domesticated live longer and consequently malignant disease develops in more of them. Cancer incidence rates now available from data compiled by an animal neoplasm registry in Alameda and Contra Costa counties, California, indicate that some of the frequent sites of cancer in man (skin, breast and the hemic and lymphatic systems) are among the most frequent sites in dogs and cats, man''s closest animal associates. 相似文献