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Herminia De Lencastre - One of the best experts on this subject based on the ideXlab platform.

  • Genetic Organization of the downstream region of the meca element in methicillin resistant staphylococcus aureus isolates carrying different polymorphisms of this region
    Antimicrobial Agents and Chemotherapy, 2000
    Co-Authors: Duarte C Oliveira, Shang W Wu, Herminia De Lencastre
    Abstract:

    We describe here the Genetic Organization of the mec element downstream of the mecA gene in 34 different methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates carrying 13 of the most frequent polymorphisms of mecA and representing the major epidemic clones of MRSA. All polymorphisms carried three common Genetic elements: the hypervariable region, a copy of IS431, and a unique 2-kb sequence (downstream constant segment, or dcs) for which no homologous sequences are found in data banks. Polymorphisms of the downstream region were shown to be caused by the presence of linearized plasmids flanked by insertion sequences (pUB110, pT181, and pI258) and the autonomous insertion sequence IS256.

  • Genetic Organization of the meca region in methicillin susceptible and methicillin resistant strains of staphylococcus sciuri
    Journal of Bacteriology, 1998
    Co-Authors: Shangwei Wu, Herminia De Lencastre, Alexander Tomasz
    Abstract:

    A homolog of the Staphylococcus aureus methicillin resistance gene mecA was recently shown to be ubiquitous in independent isolates of the animal species Staphylococcus sciuri. The mecA gene homolog and regions flanking it were cloned and sequenced from four strains of S. sciuri: strain K1 (ATCC 29062), a representative of S. sciuri subsp. sciuri; two strains (K3 and K8) representing S. sciuri subsp. rodentius; and strain K11, a representative of S. sciuri subsp. carnaticum. Strains K1 and K11 were susceptible to methicillin, while strains K3 and K8 showed heterogeneous resistance. The mecA genes of strains K1 and K11 and one of the two copies of mecA (mecA1) present in strain K3 had virtually identical DNA sequences in the mecA gene and were similar in Genetic Organization in the flanking regions. In contrast, the single copy of mecA in strain K8 and the second copy of mecA (mecA2) in strain K3 had mecA DNA sequences identical to that of S. aureus mecA, and the mecA region in these two strains was also similar to that of the same region in the S. aureus strain used for comparison. Interestingly, an open reading frame defining an N-terminal truncated polypeptide, NTORF101, with a high degree of homology to a DNA segment in the hypervariable region of methicillin-resistant S. aureus (and also similar to the Escherichia coli gene ugpQ) was also identified downstream of the mecA homolog of strain K11, representing S. sciuri subsp. carnaticum. The ugpQ-like gene is not present in methicillin-susceptible strains of S. aureus. The presence of such a ugpQ-like gene together with the homolog of mecA in strain K11 supports the speculation that these Genetic elements may be evolutionary relatives and/or precursors of the Genetic determinant of methicillin resistance in S. aureus.

Duarte C Oliveira - One of the best experts on this subject based on the ideXlab platform.

Alexander Tomasz - One of the best experts on this subject based on the ideXlab platform.

  • Genetic Organization of the meca region in methicillin susceptible and methicillin resistant strains of staphylococcus sciuri
    Journal of Bacteriology, 1998
    Co-Authors: Shangwei Wu, Herminia De Lencastre, Alexander Tomasz
    Abstract:

    A homolog of the Staphylococcus aureus methicillin resistance gene mecA was recently shown to be ubiquitous in independent isolates of the animal species Staphylococcus sciuri. The mecA gene homolog and regions flanking it were cloned and sequenced from four strains of S. sciuri: strain K1 (ATCC 29062), a representative of S. sciuri subsp. sciuri; two strains (K3 and K8) representing S. sciuri subsp. rodentius; and strain K11, a representative of S. sciuri subsp. carnaticum. Strains K1 and K11 were susceptible to methicillin, while strains K3 and K8 showed heterogeneous resistance. The mecA genes of strains K1 and K11 and one of the two copies of mecA (mecA1) present in strain K3 had virtually identical DNA sequences in the mecA gene and were similar in Genetic Organization in the flanking regions. In contrast, the single copy of mecA in strain K8 and the second copy of mecA (mecA2) in strain K3 had mecA DNA sequences identical to that of S. aureus mecA, and the mecA region in these two strains was also similar to that of the same region in the S. aureus strain used for comparison. Interestingly, an open reading frame defining an N-terminal truncated polypeptide, NTORF101, with a high degree of homology to a DNA segment in the hypervariable region of methicillin-resistant S. aureus (and also similar to the Escherichia coli gene ugpQ) was also identified downstream of the mecA homolog of strain K11, representing S. sciuri subsp. carnaticum. The ugpQ-like gene is not present in methicillin-susceptible strains of S. aureus. The presence of such a ugpQ-like gene together with the homolog of mecA in strain K11 supports the speculation that these Genetic elements may be evolutionary relatives and/or precursors of the Genetic determinant of methicillin resistance in S. aureus.

Shang W Wu - One of the best experts on this subject based on the ideXlab platform.

I F Zhimulev - One of the best experts on this subject based on the ideXlab platform.

  • Genetic Organization of interphase chromosome bands and interbands in drosophila melanogaster
    PLOS ONE, 2014
    Co-Authors: I F Zhimulev, Tatyana Yu Zykova, F P Goncharov, V A Khoroshko, Olga V Demakova, Valeriy F Semeshin, G V Pokholkova, Lidiya V Boldyreva, Darya S Demidova
    Abstract:

    Drosophila melanogaster polytene chromosomes display specific banding pattern; the underlying Genetic Organization of this pattern has remained elusive for many years. In the present paper, we analyze 32 cytology-mapped polytene chromosome interbands. We estimated molecular locations of these interbands, described their molecular and Genetic Organization and demonstrate that polytene chromosome interbands contain the 5′ ends of housekeeping genes. As a rule, interbands display preferential “head-to-head” orientation of genes. They are enriched for “broad” class promoters characteristic of housekeeping genes and associate with open chromatin proteins and Origin Recognition Complex (ORC) components. In two regions, 10A and 100B, coding sequences of genes whose 5′-ends reside in interbands map to constantly loosely compacted, early-replicating, so-called “grey” bands. Comparison of expression patterns of genes mapping to late-replicating dense bands vs genes whose promoter regions map to interbands shows that the former are generally tissue-specific, whereas the latter are represented by ubiquitously active genes. Analysis of RNA-seq data (modENCODE-FlyBase) indicates that transcripts from interband-mapping genes are present in most tissues and cell lines studied, across most developmental stages and upon various treatment conditions. We developed a special algorithm to computationally process protein localization data generated by the modENCODE project and show that Drosophila genome has about 5700 sites that demonstrate all the features shared by the interbands cytologically mapped to date.