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1.
Summary The ribosomal proteins of seven different Enterobacteriaceae were compared with those of E. coli by two-dimensional gel electrophoresis and by immunological methods. The ribosomal proteins of all Enterobacteriaceae were found to be very similar in molecular weight and in their electrophoretic properties. However, more dissimilarities could be detected by immunological methods thus indicating that few, if any, of the ribosomal proteins among the tested Enterobacteriaceae are identical. Ribosomes from all Enterobacteriaceae possess a protein which is electrophoretically identical with protein S7 from strain B (and not strain K) of E. coli.Paper No. 67 on Ribosomal Proteins. Preceding paper is by Daya-Grosjean et al., FEBS Letters, submitted.  相似文献   

2.
Summary The 30S ribosomal proteins from Bacillus stearothermophilus strains 799 and 10 were purified and correlated with those from E. coli by comparing their two-dimensional electrophoretic mobility, immunological cross-reaction, molecular weight, amino acid composition and partial amino acid sequence. A high degree of similarity was observed among the proteins from these taxonomically distant bacterial species.Paper No. 82 on Ribosomal proteins-preceding paper is by J. Horne and V. A. Erdmann, FEBS Letters, in press.N.R.C.C. No. 13514.  相似文献   

3.
Summary A ribosomal protein (L2) which binds to 23S rRNA was isolated from 70S ribosomes of several Bacillacease. It was shown by two-dimensional gel electrophoresis, molecular weight determination, amino acid analysis and immunological methods that this protein is homologous to the E. coli ribosomal protein L2 which also binds to 23S rRNA. In all Bacillaceae this protein L2 remains bound to 23S rRNA after extraction of ribosomal proteins with 4 M urea and 2 M LiCl, in contrast to E. coli. Immunological experiments demonstrated that the protein L2 of B. stearothermophilus undergoes a conformational change when it binds to 23S RNA.Paper No. 69 on Ribosomal proteins. Preceding paper is by Geisser et al., Molec. gen. Genet. 127, 129–145 (173)  相似文献   

4.
In Drosophila as in many organisms tubulins are encoded by a gene family. We have determined the complete nucleotide sequences coding for the 1 and 2 tubulins of Drosophila melanogaster and the 2 tubulin of D. hydei, and found these insect tubulins to be highly conserved and like tubulins of other organisms. This is discussed with reference to the possible functional domains of these proteins. — The 1 tubulin gene of Drosophila is constitutively expressed, whereas the 2 tubulin is expressed specifically in the testes. In D. melanogaster the amino acid sequences of these proteins are 95% homologous, differing at only 25 positions. In the testes the 2 tubulin participates in different microtubules as shown by genetic analysis (Kemphues et al. 1982). Interestingly, all of the amino acids characteristic of the testis-specific 2 tubulin are also present in the corresponding gene of D. hydei. Of special interest is the high degree of conservation of the carboxy-terminal domain in these functionally equivalent tubulins.  相似文献   

5.
Summary Electrophoresis of ribosomal proteins according to Kaltschmidt and Wittmann, 1970a, b (pH 8.6/pH 4.5 urea system) yielded 29 proteins for the small subunits and 35 and 37 proteins for the large subunits of Krebs II ascites and HeLa ribosomes, respectively. Analysis of the proteins according to a modified technique by Mets and Bogorad (1974) (pH 4.5/pH 8.6 SDS system) revealed 28 and 29 proteins in the small subunits and 37 and 38 proteins in the large subunits of Krebs II ascites and HeLa ribosomes.The molecular weights of the individual proteins were determined by: 1. three-dimensional gel electrophoresis; 2. two-dimensional gel electrophoresis at pH 4.5/pH 8.6 in SDS. The molecular weights for 40S proteins ranged from 10,000 to 39,000 dalton (number average molecular weight: 21,000). The molecular weights for the 60S proteins ranged from 14,000 to 44,000 dalton (number average molecular weight: 23,000) using the three-dimensional technique. A molecular weight range from 10,000 to 38,000 dalton (number average molecular weight: 21,000) was obtained for the 40S subunits, whereas the molecular weights for the 60S ribosomal proteins (average molecular weight: 26,000) ranged from 12,000 to 69,000 dalton using the pH 4.5/pH 8.6 SDS system.The molecular weights of Krebs II ascites and HeLa ribosomal proteins are compared with those obtained by other authors for different mammlian species.  相似文献   

6.
The effect of cycloheximide and puromycin on 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster has been studied by one-dimensional and two-dimensional SDS polyacrylamide electrophoresis. It is found that puromycin, but not cycloheximide, when applied simultaneously with the hormone enhanced the hormone-induced synthesis of the early and late proteins. However, when puromycin was applied after hormone treatment, only the late proteins were induced. The possible implication of these observations is discussed.  相似文献   

7.
The low-copy-number and broad-host-range pSM19035-derived plasmid pBT233 is stably inherited in Bacillus subtilis cells. Two distinct regions, segA and segB, enhance the segregational stability of the plasmid. Both regions function in a replicon-independent manner. The maximization of random plasmid segregation is accomplished by the recombination proficiency of the host or the presence of the pBT233 segA region. The segA region contains two open reading frames (or) [ and ]. Inactivation or deletion of or results in SegA plasmids. Better than random segregation requires an active segB region. The segB region contains two ors (or and or). Inactivation of either of the orfs does not lead to an increase in cell death, but or plasmids are randomly segregated. These results suggest that pBT233 stabilization relies on a complex system involving resolution of plasmid oligomers (segA) and on the function(s) encoded by the segB region.  相似文献   

8.
Cell-cycle-related variation in proteins in suspension-cultured rice cells   总被引:1,自引:0,他引:1  
To understand the cell cycle process in plants, we searched for proteins that quantitatively change during the cell cycle in suspension-cultured rice (Oryza sativa L.) cells. The proteins were analyzed by a two-dimensional polyacrylamide gel electrophoresis image-analysis system. We detected 11 proteins that quantitatively changed during the cell cycle, among which -tubulins and a calreticulin-like protein were identified. The amounts of -tubulin proteins were low in the M phase and high in the G1 phase. In contrast, mRNAs for two of the three types of -tubulin were high in the M phase of the cell cycle. The addition of protease inhibitors MG132 or E64d to the cells decreased the -tubulin proteins during 24 h, suggesting that -tubulin proteins are degraded in vivo by proteases other than those whose activities are inhibited by MG132 or E64d.  相似文献   

9.
4-O-Glycosylation of 2-azidoethyl 2,3,6-tri-O-benzyl-4-O-(2,3-di-O-benzyl-6-O-benzoyl--D-galactopyranosyl)--D-glucopyranoside with a disaccharide donor, 4-trichloroacetamidophenyl 4,6-di-O-acetyl-2-deoxy-3-O-(2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-1-thio-2-trichloroacetamido--D-galactopyranoside, in dichloromethane in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid resulted in a tetrasaccharide, 2-azidoethyl (2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-(1 3)-(4,6-di-O-acetyl-2-deoxy-2-trichloroacetamido--D-galactopyranosyl)-(1 4)-(2,3-di-O-benzyl-6-O-benzoyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside, in 69% yield. The complete removal of O-protecting groups in the tetrasaccharide, the replacement of N-trichloroacetyl by N-acetyl group, and the reduction of the aglycone azide group to amine led to the target aminoethyl glycoside of -D-Gal-(1 3)--D-GalNAc-(1 4)--D-Gal-(1 4)--D-Glc-OCH2CH2NH2 containing the oligosaccharide chain of asialo-GM1 ganglioside in 72% overall yield. Selective 3-O-glycosylation of 2-azidoethyl 2,3,6-tri-O-benzyl-4-O-(2,6-di-O-benzyl--D-galactopyranosyl)--D-glucopyranoside with thioglycoside methyl (ethyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero--D-galacto-2-nonulopyranosyl)oate in acetonitrile in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid afforded 2-azidoethyl [methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero--D-galacto-2-nonulopyranosyl)oate]-(2 3)-(2,6-di-O-benzyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside, the selectively protected derivative of the oligosaccharide chain of GM3 ganglioside, in 79% yield. Its 4-O-glycosylation with a disaccharide glycosyl donor, (4-trichloroacetophenyl-4,6-di-O-acetyl-2-deoxy-3-O-(2,3,4,6-tetra-O-acetyl--D-galactopyranosyl) 1-thio-2-trichloroacetamido--D-galactopyranoside in dichloromethane in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid gave 2-azidoethyl (2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-(1 3)-(4,6-di-O-acetyl-2-deoxy-2-trichloroacetamido--D-galactopyranosyl)-(1 4)-{[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero--D-galacto-2-nonulopyranosyl)onate]-(2 3)}-(2,6-di-O-benzyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside in 85% yield. The resulting pentasaccharide was O-deprotected, its N-trichloroacetyl group was replaced by N-acetyl group, and the aglycone azide group was reduced to afford in 85% overall yield aminoethyl glycoside of -D-Gal-(1 3)--D-GalNAc-(1 4)-[-D-Neu5Ac-(2 3)]--D-Gal-(1 4)--D-Glc-OCH2CH2NH2 containing the oligosaccharide chain of GM1 ganglioside.  相似文献   

10.
Phylogenetic analysis of the endo--1,4-glucanase gene family of Arabidopsis and other plants revealed a clear distinction in three subfamilies (, , and ). The - and -subfamily contains proteins believed to be involved in a number of physiological roles such as elongation, ripening, and abscission. The -subfamily is composed of proteins that are predicted to have a membrane-spanning domain and to be localized at the plasma membrane. Some of these proteins have been linked to cellulose biosynthesis by serving to hydrolyze a lipid-linked intermediate that acts as a primer for the elongation of -glucan chains during cellulose synthesis at the plasma membrane. Similar glucanases are important in cellulose biosynthesis in bacteria. Searches in the genomes of unrelated organisms that make cellulose, such as Ciona intestinalis and Dictyostelium discoideum, revealed the presence of membrane-linked endo--1,4-glucanases and it is suggested that these might also have a role in cellulose synthesis.  相似文献   

11.
Summary Meiotic chromosome pairing and Giemsa C-banding analyses in crosses of several European blue-grained wheat strains with Chinese Spring double ditelosomic and other aneuploid lines showed that Triticum aestivum Blaukorn strains Berlin, Probstdorf, Tschermak, and Weihenstephan are chromosome substitutions, in which the complete wheat chromosome 4A pair is replaced, whereas the strains Brünn and Moskau are 4B substitutions. The alien chromosome pair in all of these strains is an A genome chromosome (4A) from diploid Triticum monococcum or T. boeoticum not present in common tetraploid and hexaploid cultivated wheats. The Blaukorn strain Weihenstephan W 70a86 possesses, in addition to a rye chromosome pair 5R compensating for the loss of part of chromosome 5D, a 4A/5DL translocation replacing chromosome pair 4B of wheat.  相似文献   

12.
Computer based sequence comparisons indicate partial sequence homology between human c-myc, Rous sarcoma virus, adenovirus 7, and simian sarcoma virus proteins and the cytoskeletal proteins desmin, keratin and vimentin. In addition, sections of the oncogene proteins showed partial but significant homology to and subunits of transducin, -II and -BP crystallins showed partial but significant homology to the cytoskeletal proteins keratin, vimentin, desmin, and -tubulin, and to adenovirus 7 and simian sarcoma virus transforming gene proteins. -BP crystallin showed partial but significant homology to Rous sarcoma virus protein, and to and y subunits of transducin. Both crystallins showed partial sequence homology to the GTP-binding protein elongation factor TU fromEscherichia coli . These sequence homologies suggest a link between the mechanisms of normal lens cell differentiation, involving modifications to the cytoskeleton and subsequent changes to the pattern of protein synthesis, and mechanisms of neoplastic transformation. Furthermore the transducin-like region on -crystallin may be important for its interaction with lens membranes and the maintenance of short-range order for lens transparency.  相似文献   

13.
Genotypes of Drosophila hydei having deficiencies of specific sections of X or Y chromosomal heterochromatin are characterized by heterogeneous rRNA gene numbers in their nonpolyploid organs. Depending on which sex heterochromatin portion is deleted, the rDNA amount in either brain or thoracic muscle cells or in both is increased threefold. This rDNA overreplication cannot be a compensation for a deficiency in ribosomal gene number, since the phenomenon also occurs in genotypes with a high initial rRNA gene numbers.  相似文献   

14.
Summary The progenies of two different rye test-crosses were analyzed for secalin proteins by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) using unreduced and reduced aqueous ethanol extracts. Segregation for two high-molecular-weight secalin bands (Glu-R1 or Sec3), one -secalin band (Gli-R1 or Sec-1), two 40K -secalin bands (Gli-R1 or Sec1) and two -type secalin bands (new locus) were studied. One recombinant between - and -secalins was found in one test-cross. The new locus, designated Gli-R3 or Sec-4, was mapped between Glu-R1 and Gli-R1, more displaced towards Gli-R1. In test-cross 1 recombination between Glu-R1 and Gli-R3 was 33.80±3.22%, and between Gli-R3 and Gli-R1, 12.04±2.21%. In the other test-cross the map distances were relatively similar but smaller, likely due to less recombination within two different species of Secale. Genes coding for 40K -secalins at Gli-R1 were likely proximal to the centromere with respect to genes coding for -secalins at the same complex locus.  相似文献   

15.
Zusammenfassung An Laboratoriumszuchten vonReticulitermes lucifugus Rossi undReticulitermes flavipes Kollar (aus den Hamburger Befallsgebieten) werden Beobachtungen zur Biologie der Ersatzgeschlechtstiere mitgeteilt. Für die Durchführung dieser Beobachtungen wurden besondere Schaunester eingerichtet. Folgende Punkte der beobachteten Verhaltensweisen werden hier hervorgehoben: Die Nymphen der Ersatzgeschlechtstiere sammeln sich stets in Herden von 80–100 Einzeltieren und werden von einer Gruppe Arbeiter (als Hütehunde) bewacht. Die Arbeiter halten die Nymphen auf einem engen Raum zusammen und versuchen andere Nestgenossen von den Nymphen fernzuhalten. Alle ein bis zwei Tage wechseln die Herden ihren Standort. Das Weiterziehen geschieht gleichfalls in Form von Herden.Die Ernährung der Nymphen geschieht auf stomodealem Wege durch die Arbeiter. *** DIRECT SUPPORT *** A0180089 00007  相似文献   

16.
Human macrophage inflammatory protein-1 (hMIP-1) and human macrophage inflammatory protein-1 (hMIP-1) are chemokines involved in a diverse range of immunological effects. Both hMIP-1 and hMIP-1 are involved in the activation of monocytes and THP-1 cells probably through a common receptor(s). However, only hMIP-1 can bind to neutrophils with high affinity, presumably through CC-CKR1 (CKR1). Since the structure of these two proteins is highly conserved, non-conserved amino acids must define the disparate binding patterns that these two proteins exhibit. Measurements of binding, chemotaxis and calcium influx conducted with hMIP-1 and hMIP-1 chimeric proteins and mutants show that two amino acids (37K and 43L) are important in the binding and signaling of hMIP-1 through CKR1. Furthermore, we also show that mutations of the three charged amino acids at the C-terminus of hMIP-1 and hMIP-1 (amino acids 61, 65 and 67), do not adversely affect the binding to THP-1 cells.  相似文献   

17.
Summary A grpE mutation of Escherichia coli K12, which blocks DNA replication of the phage (Saito and Uchida, 1977), was mapped at 56 min on the standard genetic map. A transducing phage, grpE22, carrying the wild type allele of the grpE gene was constructed in vitro. Structures of grpE22 and its viable deletion derivatives were determined by electron microscopic analyses of appropriate heteroduplexes. Proteins coded by the bacterial DNA incorporated into the transducing phages were detected by two-dimensional gel electrophoresis. The results showed that the product of the grpE gene is a weakly acidic protein of molecular weight 24,000. Structural genes for two ribosomal proteins, rplS (L19) and rpsP (S16) were also shown to be carried by grpE22.  相似文献   

18.
Summary Hemoglobin Vancouver is a new abnormal hemoglobin with an amino acid substitution of the normal aspartyl residue 73 of the chain by a tyrosyl residue. It was discovered in a man of Chinese descent in association with thalassemia. It was subsequently detected in a sister in association with normal Hb A. The oxygen affinity of the abnormal hemoglobin is decreased but its subunit interaction is normal. The Bohr effect may be slightly increased.This is the fourth abnormal hemoglobin to be found with a substitution at73. The others are Hb C-Harlem ( 2 2 6GluVal and 73 AspAsn), Hb Korle-Bu ( 2 2 73 AspAsn), and Hb Mobile ( 2 2 73 AspVal). Although Hb Mobile was found in the present studies to have a decreased affinity for oxygen, Hbs C-Harlem and Korle-Bu have been reported to be normal. These observations of functional differences for variants of73 added to earlier observations of the role of the normal73 residue to the aggregation of sickle deoxyhemoglobin indicate that this position of the molecule may be important in intra as well as intermolecular interactions.  相似文献   

19.
Summary Human -galactosidase-deficient skin fibroblasts from a patient with generalized gangliosidosis (GM1-gangliosidosis type I) were treated with phage plac DNA, coding for Escherichia coli -galactosidase (-D-galactoside galactohydrolase, EC 3.2.1.23). New -galactosidase activity detected in cell extracts of phage DNA-treated GM1-gangliosidosis fibroblasts continued to vary considerably from one experiment to another. It behaved like the E. coli z-gene product upon immunochemical and physicochemical investigation. In some experiments the antigenic behavior of resultant -galactosidase activity in plac DNA-treated cells resembled that of mutant E. coli -galactosidase. Among the factors and variables that may be responsible for the variation in the results obtained here and elsewhere, low physical binding between prokaryotic mRNA sequences and fibroblast ribosomal RNA could play a part connected with effective translation. This hypothesis is discussed under the aspect of a comparison of the ribosomal binding site of lac z mRNA with the 3-terminus of the eukaryotic 18s ribosomal RNA, which shows limited possibilities for base-pairing interactions.More extensive possibilities for forming Watson-Crick base pairs between their initiation site and the eukaryotic ribosomal binding site exist for other prokaryotic messengers, such as those of Q-replicase, f 1-coat protein, or UDPG-4-epimerase.  相似文献   

20.
We have studied the spatial pattern of accumulation of chitinase (EC 3.2.1.14) and -1,3-glucanase (EC 3.2.1.39) in ethylene-treated leaves of bean (Phaseolus vulgaris L.). Electron-microscopical examination of chemically fixed tissue demonstrated the presence of large electron-dense aggregates in the vacuoles of ethylene-treated leaf cells. No such vacuolar structures were observed in untreated control cells. Immunogold labelling with antisera directed against the basic forms of chitinase and -1,3-glucanase indicated that the vacuolar aggregates were the major site of accumulation of chitinase and -1,3-glucanase. The chitinase- and -1,3-glucanase-containing vacuolar aggregates were not randomly distributed within the leaf tissue but were restricted to the lower epidermal cells and to parenchyma cells adjacent to vascular strands. In addition, heavy -1,3-glucanase labelling was observed over spongy plugs of expanded middle-lamella material that appear to occlude the transition regions between the airspaces underlying the stomata and those throughout the rest of the leaf. Some labelling was also seen to extend along the surface layer of the cell walls lining all of the airspaces. Protein analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting as well as enzyme-activity measurements showed that the peeled lower epidermis of the ethylene-treated leaves contained on a protein and on a per-weight basis several times more chitinase and -1,3-glucanase than the remainder of the leaf.Abbreviation in Text SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis Abbreviations in Micrographs AS air space - C chloroplast - EP (epidermal) cell - G guard cell - P parenchyma cell - S stoma - V vacuole - VE] vein - VP vascular parenchyma cell - W cell wall - X xylem We thank Dr. L.A. Hadwiger, Pullman, Wash., and Dr. U. Vögeli, Lexington, Ky., for their kind gifts of antibodies. This work was supported by the National Science Foundation grant DCB-8615763 to L.A.S.  相似文献   

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