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41.
Biochemical similarity among serologically distinct flagellins of Campylobacter jejuni 总被引:1,自引:0,他引:1
Irving Nachamkin Ruth-Hogue Angeletti Michael B. Prystowsky 《FEMS microbiology letters》1988,51(2-3):149-152
Abstract We describe a simplified method for obtaining highly purified flagellin, suitable for biochemical analysis using HPLC-gel permeation. Amino acid composition and N-terminal sequence analyses were performed on flagellins from serologically distinct isolates. The amino acid composition of flagellin from 10 strains was very similar. The N-terminal amino acid sequence is highly conserved. Significant sequence homology was found with flagellin of Bacillus subtilis . 相似文献
42.
43.
A flexible method to align large numbers of biological sequences 总被引:5,自引:0,他引:5
William R. Taylor 《Journal of molecular evolution》1988,28(1-2):161-169
Summary A method for the alignment of two or more biological sequences is described. The method is a direct extension of the method of Taylor (1987) incorporating a consensus sequence approach and allows considerable freedom in the control of the clustering of the sequences. At one extreme this is equivalent to the earlier method (Taylor 1987), whereas at the other, the clustering approaches the binary method of Feng and Doolittle (1987). Such freedom allows the program to be adapted to particular problems, which has the important advantage of resulting in considerable savings in computer time, allowing very large problems to be tackled. Besides a detailed analysis of the alignment of the cytochrome c superfamily, the clustering and alignment of the PIR sequence data bank (3500 sequences approx.) is described. 相似文献
44.
Cloning and sequencing of the genes encoding the large and the small subunits of the H2 uptake hydrogenase (hup) of Rhodobacter capsulatus 总被引:12,自引:0,他引:12
Michèle Leclerc Annette Colbeau Béatrice Cauvin Paulette M. Vignais 《Molecular & general genetics : MGG》1988,214(1):97-107
Summary The structural genes (hup) of the H2 uptake hydrogenase of Rhodobacter capsulatus were isolated from a cosmid gene library of R. capsulatus DNA by hybridization with the structural genes of the H2 uptake hydrogenase of Bradyrhizobium japonicum. The R. capsulatus genes were localized on a 3.5 kb HindIII fragment. The fragment, cloned onto plasmid pAC76, restored hydrogenase activity and autotrophic growth of the R. capsulatus mutant JP91, deficient in hydrogenase activity (Hup-). The nucleotide sequence, determined by the dideoxy chain termination method, revealed the presence of two open reading frames. The gene encoding the large subunit of hydrogenase (hupL) was identified from the size of its protein product (68108 dalton) and by alignment with the NH2 amino acid protein sequence determined by Edman degradation. Upstream and separated from the large subunit by only three nucleotides was a gene encoding a 34 256 dalton polypeptide. Its amino acid sequence showed 80% identity with the small subunit of the hydrogenase of B. japonicum. The gene was identified as the structural gene of the small subunit of R. capsulatus hydrogenase (hupS). The R. capsulatus hydrogenase also showed homology, but to a lesser extent, with the hydrogenase of Desulfovibrio baculatus and D. gigas. In the R. capsulatus hydrogenase the Cys residues, (13 in the small subunit and 12 in the large subunit) were not arranged in the typical configuration found in [4Fe–4S] ferredoxins. 相似文献
45.
Identification, cloning, nucleotide sequence and chromosomal map location of hns, the structural gene for Escherichia coli DNA-binding protein H-NS 总被引:10,自引:0,他引:10
Cynthia L. Pon Raffaele A. Calogero Claudio O. Gualerzi 《Molecular & general genetics : MGG》1988,212(2):199-202
Summary Beginning with a synthetic oligonucleotide probe derived from its amino acid sequence, we have identified, cloned and sequenced the hns gene encoding H-NS, an abundant Escherichia coli 15 kDa DNA-binding protein with a possible histone-like function. The amino acid sequence of the protein deduced from the nucleotide sequence is in full agreement with that determined for H-NS. By comparison of the restriction map of the cloned gene and of its neighboring regions with the physical map of E. coli K12 as well as by hybridization of the hns gene with restriction fragments derived from the total chromosome, we have located the hns gene oriented counterclockwise at 6.1 min on the E. coli chromosome, just before an IS30 insertion element. 相似文献
46.
David K. Grandy Richard Leduc Haripriya Makam Thomas Flanagan Emanuel J. Diliberto Jr. Olivier Civelli O. Humberto Viveros 《Cellular and molecular neurobiology》1992,12(2):185-192
1. A novel 1745-dalton pyroglutamyl peptide (BAM-1745)6 was recently isolated and characterized from bovine adrenal medulla chromaffin granules. Its amino acid sequence was found to be 93% identical to residues 580-593 of human chromogranin B (secretogranin I). 2. Based on this sequence a degenerate oligonucleotide probe was synthesized and used to identify a 2.4-kb bovine adrenal medulla chromogranin B cDNA. 3. The deduced polypeptide is 647 amino acids long and begins with a putative signal sequence of 20 residues as in the human, rat, and mouse proteins. Also conserved in the bovine protein is a tyrosine residue which may be sulfated, two N-terminal cysteines, and many paired basic amino acids which may serve as sites of posttranslational processing. The peptide BAM-1745 is flanked by paired basic amino acids and therefore is most likely a product of posttranslational processing. Bovine chromogranin B is 67, 58, and 58% identical to the human, rat, and mouse chromogranin B proteins, respectively. 4. The carboxyl terminus of bovine chromogranin B, including BAM-1745, was found to be the most conserved region of the polypeptide and may identify it as an important functional domain. 相似文献
47.
48.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
49.
50.
Robert G. Rutledge Thérèse Quellet Jiro Hattori Brian L. Miki 《Molecular & general genetics : MGG》1991,229(1):31-40
Summary The Brassica napus rapeseed cultivar Topas contains an acetohydroxyacid synthase (AHAS) multigene family consisting of five members (AHAS 1–5). DNA sequence analysis indicate that AHAS1 and AHAS3 share extensive homology. They probably encode the AHAS enzymes essential for plant growth and development. AHAS2 has diverged significantly from AHAS1 and AHAS3 and has unique features in the coding region of the mature polypeptide, transit peptide and upstream non-coding DNA, which raises the possibility that it has a distinct function. AHAS4 and AHAS5 have interrupted coding regions and may be defective. The complexity of the AHAS multigene family in the allotetraploid species B. napus is much greater than reported for Arabidopsis thaliana and Nicotiana tabacum. Analysis of the presumptive progenitor diploid species B. campestris and B. oleracea indicated that AHAS2, AHAS3 and AHAS4 originate from the A genome, whereas AHAS1 and AHAS5 originate from the C genome. Further variation within each of the AHAS genes in these species was found. 相似文献