scholarly journals Tellurium and related element fractionation in porphyry-epithermal systems, Limnos Island, Greece

2021 ◽  
Author(s):  
Frederik Börner ◽  
Manuel Keith ◽  
Jonas Bücker ◽  
Panagiotis Voudouris ◽  
Reiner Klemd ◽  
...  
Keyword(s):  
Element Fractionation ◽  
Related Element

scholarly journals A Modified Autonomous En Transposon in Maize (Zea mays L.) Elicits a Differential Response of Reporter Alleles

Genetics ◽  
1997 ◽  
Vol 147 (3) ◽  
pp. 1329-1338
Author(s):  
Peter A Peterson
Keyword(s):  
Molecular Structure ◽  
Binding Sites ◽  
Molecular Basis ◽  
Zea Mays L ◽  
Phenotypic Expression ◽  
Terminal Inverted Repeat ◽  
Coding Sequences ◽  
Defective Element ◽  
Related Element ◽  
Unstable Genes

Transposable elements in maize are composed of a defined molecular structure that includes coding sequences, determiners of functionality and ordered terminal motifs that provide binding sites for transposase proteins. Alterations in these components change the phenotypic expression of unstable genes with transposon inserts. The molecular basis for the altered timing and frequency of transposition as determined by the size and number of spots on kernels or stripes on leaves has generally been described for defective inserts in genes. Most differential patterns can be ascribed to alterations in the terminal motifs of the reporter allele structure that supplies a substrate (terminal inverted repeat motifs) for transposase activity. For autonomously functioning alleles, the explanations for changes in phenotype are not so clear. In this report, an En-related element identified as F-En is described that shares with En the recognition of a specific defective element c1(mr)888104 but differs from En in that this F-En element does not recognize the canonical c1(mr) elements that are recognized by En. Evidence is provided suggesting that F-En does not recognize other En/Spm-related defective elements, some of whose sequences are known. This modified En arose from a c1-m autonomously mutating En allele.

scholarly journals Effects of the Movement of Insertion Sequences on the Structure of VanA Glycopeptide Resistance Elements in Enterococcus faecium

2000 ◽  
Vol 44 (5) ◽  
pp. 1362-1364 ◽  
Author(s):  
Ana L. C. Darini ◽  
Marie-France I. Palepou ◽  
Neil Woodford
Keyword(s):  
Structural Change ◽  
Inverted Repeat ◽  
Enterococcus Faecium ◽  
Insertion Sequence ◽  
Host Strain ◽  
Insertion Sequences ◽  
Glycopeptide Resistance ◽  
Related Element

ABSTRACT A Tn1546-related element with IS1216V at position 8839 underwent a structural change after storage of the host strain of Enterococcus faecium at 4°C. The element acquired IS1542 at position 3932, nucleotides 8732 to 8831 were deleted, and the first 3417 nucleotides were lost and replaced by an inverted copy of the IS1216V–vanY–vanZ-inverted-repeat block from the 3′ end. Insertion sequence movement is likely to play a key role in the evolution of VanA resistance elements.

scholarly journals Mapping the regions carrying the three contiguous antibiotic resistance genes aadE, sat4, and aphA-3 in the genomes of staphylococci.

1997 ◽  
Vol 41 (5) ◽  
pp. 1024-1032 ◽  
Author(s):  
A Derbise ◽  
S Aubert ◽  
N El Solh
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Unknown Function ◽  
Antibiotic Resistance Genes ◽  
Open Reading Frames ◽  
Restriction Fragments ◽  
Internal Part ◽  
Reading Frames ◽  
Related Element

Tn5405 (12 kb) is a staphylococcal composite transposon delimited by two inverted copies of IS1182, one of which contains IS1181. The internal part of this transposon carries three antibiotic resistance genes, aphA-3, aadE, and sat4, and three open reading frames (ORFs), orfx, orfy, and orfz, of unknown function. The dispersion of Tn5405 and the genes and ORFs included in this transposon were investigated in 50 epidemiologically unrelated staphylococci carrying aphA-3. Twenty-three maps, distinguishable by the presence or absence of the investigated genes or ORFs and/or by the sizes of the restriction fragments carrying them, were identified. Four isolates carried Tn5405, and 15 other isolates contained a Tn5405-related element. IS1182 was not detected in the aphA-3 regions mapped in 31 isolates which carried the following combinations: orfx, orfy, aadE, sat4, and aphA-3 +/- orfz; orfy, aadE, sat4, and aphA-3 +/- orfz; and aadE, sat4, aphA-3, and orfz. In all isolates, the genes and ORFs investigated were in relative positions similar to those in Tn5405. Thus, the internal part of Tn5405 appeared to be partially conserved with the maintenance, in all of the isolates, of at least the three antibiotic resistance genes.

scholarly journals Redox regulation of DNA binding activity of DREF (DNA replication-related element binding factor) in Drosophila

2004 ◽  
Vol 378 (3) ◽  
pp. 833-838 ◽  
Author(s):  
Tae-Yeong CHOI ◽  
S. Young PARK ◽  
Ho-Sung KANG ◽  
Jae-Hun CHEONG ◽  
Han-Do KIM ◽  
...  
Keyword(s):  
Dna Replication ◽  
Dna Binding ◽  
Redox State ◽  
Redox Regulation ◽  
Binding Activity ◽  
Dna Binding Activity ◽  
Cell Extracts ◽  
Binding Factor ◽  
Related Element ◽  
Intracellular Redox

DREF [DRE (DNA replication-related element) binding factor] is an 80 kDa polypeptide homodimer which plays an important role in regulating cell proliferation-related genes. Both DNA binding and dimer formation activities are associated with residues 16–115 of the N-terminal region. However, the mechanisms by which DREF dimerization and DNA binding are regulated remain unknown. Here, we report that the DNA binding activity of DREF is regulated by a redox mechanism, and that the cysteine residues are involved in this regulation. Electrophoretic mobility shift analysis using Drosophila Kc cell extracts or recombinant DREF proteins indicated that the DNA binding domain is sufficient for redox regulation. Site-directed mutagenesis and transient transfection assays showed that Cys59 and/or Cys62 are critical both for DNA binding and for redox regulation, whereas Cys91 is dispensable. In addition, experiments using Kc cells indicated that the DNA binding activity and function of DREF are affected by the intracellular redox state. These findings give insight into the exact nature of DREF function in the regulation of target genes by the intracellular redox state.

LEDGF Binds to Heat Shock and Stress-Related Element to Activate the Expression of Stress-Related Genes

2001 ◽  
Vol 283 (4) ◽  
pp. 943-955 ◽  
Author(s):  
Dhirendra P. Singh ◽  
Nigar Fatma ◽  
Akira Kimura ◽  
Leo T. Chylack ◽  
Toshimichi Shinohara
Keyword(s):  
Heat Shock ◽  
Stress Related Genes ◽  
Related Element

scholarly journals ISLpl1 Is a Functional IS30-Related Insertion Element in Lactobacillus plantarum That Is Also Found in Other Lactic Acid Bacteria

2003 ◽  
Vol 69 (10) ◽  
pp. 6032-6040 ◽  
Author(s):  
Hervé Nicoloff ◽  
Françoise Bringel
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Lactobacillus Plantarum ◽  
Point Mutations ◽  
Mobile Element ◽  
Distribution Data ◽  
Insertion Element ◽  
Is Element ◽  
Spontaneous Mutants ◽  
Related Element

ABSTRACT We describe the first functional insertion sequence (IS) element in Lactobacillus plantarum. ISLpl1, an IS30-related element, was found on the pLp3 plasmid in strain FB335. By selection of spontaneous mutants able to grow in the presence of uracil, it was demonstrated that the IS had transposed into the uracil phosphoribosyltransferase-encoding gene upp on the FB335 chromosome. The plasmid-carried IS element was also sequenced, and a second potential IS element was found: ISLpl2, an IS150-related element adjacent to ISLpl1. When Southern hybridization was used, the copy number and genome (plasmid versus chromosome) distribution data revealed different numbers and patterns of ISLpl1-related sequences in different L. plantarum strains as well as in Pediococcus strains. The ISLpl1 pattern changed over many generations of the strain L. plantarum NCIMB 1406. This finding strongly supports our hypothesis that ISLpl1 is a mobile element in L. plantarum. Database analysis revealed five quasi-identical ISLpl1 elements in Lactobacillus, Pediococcus, and Oenococcus strains. Three of these elements may be cryptic IS, since point mutations or 1-nucleotide deletions were found in their transposase-encoding genes. In some cases, ISLpl1 was linked to genes involved in cold shock adaptation, bacteriocin production, sugar utilization, or antibiotic resistance. ISLpl1 is transferred among lactic acid bacteria (LAB) and may play a role in LAB genome plasticity and adaptation to their environment.

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