Search results for "nuclei"
showing 10 items of 1273 documents
The cold shock response of the psychrotrophic bacterium Pseudomonas fragi involves four low-molecular-mass nucleic acid-binding proteins
1997
The psychrotrophic bacterium Pseudomonas fragi was subjected to cold shocks from 30 or 20 to 5 degrees C. The downshifts were followed by a lag phase before growth resumed at a characteristic 5 degrees C growth rate. The analysis of protein patterns by two-dimentional gel electrophoresis revealed overexpression of 25 or 17 proteins and underexpression of 12 proteins following the 30- or 20-to-5 degrees C shift, respectively. The two downshifts shared similar variations of synthesis of 20 proteins. The kinetic analysis distinguished the induced proteins into cold shock proteins (Csps), which were rapidly but transiently overexpressed, and cold acclimation proteins (Caps), which were more or …
A multidomain xylanase from a Bacillus sp. with a region homologous to thermostabilizing domains of thermophilic enzymes
1999
The gene xynC encoding xylanase C from Bacillus sp. BP-23 was cloned and expressed in Escherichia coli. The nucleotide sequence of a 3538 bp DNA fragment containing xynC gene was determined, revealing an open reading frame of 3258 bp that encodes a protein of 120,567 Da. A comparison of the deduced amino acid sequence of xylanase C with known beta-glycanase sequences showed that the encoded enzyme is a modular protein containing three different domains. The central region of the enzyme is the catalytic domain, which shows high homology to family 10 xylanases. A domain homologous to family IX cellulose-binding domains is located in the C-terminal region of xylanase C, whilst the N-terminal r…
Vibrio sinaloensis sp. nov., isolated from the spotted rose snapper, Lutjanus guttatus Steindachner, 1869.
2008
Nine bacterial strains were studied by means of rep-PCR, 16S rRNA gene sequence analysis, DNA-DNA hybridization and physiological characterization. Typing analysis by means of rep-PCR showed that all nine strains were highly homogeneous, with similarities above 94 %. The strains were isolated from the same geographical area (Mazatlan, Sinaloa state, Mexico) and the same type of host (cultured rose snapper, Lutjanus guttatus), although from different individuals and organs. Comparison of the almost-complete 16S rRNA gene sequences of five strains showed that they belonged to the genus Vibrio and are closely related to the type strains of Vibrio brasiliensis and Vibrio hepatarius, with simila…
Complex evolution of tandem-repetitive DNA in the Chironomus thummi species group.
1997
The subspecies Chironomus thummi thummi and C. t. piger display dramatic differences in the copy number and chromosomal localization of a tandemly repeated DNA family (Cla elements). In order to analyze the evolutionary dynamics of this repeat family, we studied the organization of Cla elements in the related outgroup species C. luridus. We find three different patterns of Cla element organization in C. luridus, showing that Cla elements may be either strictly tandem-repetitive or be an integral part of two higher-order tandem repeats (i.e., Hinf[lur] elements, Sal[lur] elements). All three types of Cla-related repeats are localized in the centromeres of C. luridus chromosomes. This suggest…
Functional variants of 5S rRNA in the ribosomes of common sea urchin Paracentrotus lividus
2012
Abstract We have previously reported a molecular and cytogenetic characterization of three different 5S rDNA clusters in the sea urchin Paracentrotus lividus ; this study, performed at DNA level only, lends itself as starting point to verify that these clusters could contain transcribed genes, then, to demonstrate the presence of heterogeneity at functional RNA level, also. In the present work we report in P. lividus ribosomes the existence of several transcribed variants of the 5S rRNA and we associate all transcribed variants to the cluster to which belong. Our finding is the first demonstration of the presence of high heterogeneity in functional 5S rRNA molecules in animal ribosomes, a f…
The coat protein of prunus necrotic ringspot virus specifically binds to and regulates the conformation of its genomic RNA
2003
AbstractBinding of coat protein (CP) to the 3′ nontranslated region (3′-NTR) of viral RNAs is a crucial requirement to establish the infection of Alfamo- and Ilarviruses. In vitro binding properties of the Prunus necrotic ringspot ilarvirus (PNRSV) CP to the 3′-NTR of its genomic RNA using purified E. coli- expressed CP and different synthetic peptides corresponding to a 26-residue sequence near the N-terminus were investigated by electrophoretic mobility shift assays. PNRSV CP bound to, at least, three different sites existing on the 3′-NTR. Moreover, the N-terminal region between amino acid residues 25 to 50 of the protein could function as an independent RNA-binding domain. Single exchan…
Interspecies comparison of neuroglobin, cytoglobin and myoglobin: Sequence evolution and candidate regulatory elements
2003
Neuroglobin and cytoglobin are two novel members of the vertebrate globin family. Their physiological role is poorly understood, although both proteins bind oxygen reversibly and may be involved in cellular oxygen homeostasis. Here we investigate the selective constraints on coding and non-coding sequences of the neuroglobin and cytoglobin genes in human, mouse, rat and fish. Neuroglobin and cytoglobin are highly conserved, displaying very low levels of non-synonymous nucleotide substitutions. An oxygen supply function predicts distinct modes of gene regulation, involving hypoxia-responsive transcription factors. To detect conserved candidate regulatory elements, we compared the neuroglobin…
Engineering a 2D protein-DNA crystal.
2005
(Figure Presented) Weaving with DNA: A DNA-binding protein was used to control the structure of a self-assembled 2D crystal. In the absence of protein, four oligonucleotides hybridize to form a Kagome lattice of interwoven double helices with p3 symmetry (see image). Addition of protein RuvA during assembly changes the symmetry and connectivity to give a DNA-protein crystal with an approximately square unit cell. © 2005 Wiley-VCH Verlag GmbH and Co. KGaA.
Putative evolutionary origin of plasmids carrying the genes involved in leucine biosynthesis in Buchnera aphidicola (endosymbiont of aphids)
1997
An 8.5-kb plasmid encoding genes (leuABCD) involved in leucine biosynthesis and a small plasmid of 1.74 kb of yet unknown function were found in the intracellular symbiont, Buchnera aphidicola, of two divergent aphid species, Thelaxes suberi and Tetraneura caerulescens, respectively. The leuABCD-carrying plasmid (pBTs1) was amplified from total aphid DNA by inverse long PCR, using outwardly oriented oligonucleotide primers specific to leuA. The resulting 8.2-kb PCR fragment as well as the 1.74-kb plasmid (pBTc1) were cloned and sequenced. pBTs1 differed from a previously described B. aphidicola plasmid (pRPE) of the aphid Rhopalosiphum padi by the presence of a small heat shock gene (ibp) a…
Conserved Structure and Promoter Sequence Similarity in the Mouse and Human Genes Encoding the Zinc Finger Factor BERF-1/BFCOL1/ZBP-89
2001
Abstract We have characterized the genomic structure of the mouse Zfp148 gene encoding Beta-Enolase Repressor Factor-1 (BERF-1), a Kruppel-like zinc finger protein involved in the transcriptional regulation of several genes, which is also termed ZBP-89, BFCOL1. The cloned Zfp148 gene spans 110 kb of genomic DNA encompassing the 5′-end region, 9 exons, 8 introns, and the 3′-untranslated region. The promoter region displays the typical features of a housekeeping gene: a high G+C content and the absence of canonical TATA and CAAT boxes consistent with the multiple transcription initiation sites determined by primary extension analysis. Computer-assisted search in the human genome database allo…