• Effects of ionizing radiation on the survival of bacterial spares in artificial martia regolith

      Moeller, Ralf; Rohde, Manfred; Reitz, Günther; Department of Medical Microbiology, Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany (Science Direct, 2010-04)
    • Entry and intracellular survival of group B streptococci in J774 macrophages.

      Valenti-Weigand, P; Benkel, P; Rohde, Manfred; Chhatwal, G S (1996-07)
    • Exocytotic process as a novel model for mineralization by osteoblasts in vitro and in vivo determined by electron microscopic analysis.

      Rohde, Manfred; Mayer, H; Department of Microbial Pathogenesis, Helmholtz Center for Infection Research, Inhoffenstrasse 7, D-38124 Braunschweig, Germany. manfred.rohde@helmholtz-hzi.de (2007-05)
      The process of biomineralization has been examined during osteoblastic differentiation of bone marrow stroma cells (BMSCs) from embryonic chick in culture and in periosteum itself by a number of different techniques including transmission and scanning electron microscopy. In cell culture of BMSCs at days 20-25, crystals were accumulated extracellularly in the collagen matrix, resulting in large plate-like crystallites and noncollagen associated on the culture disk surface. In contrast, up to days 10-18, mainly intracellular mineralization was visible by numerous needle-like crystal structures in the cell cytoplasm and in vacuoles. After 20-30 days, the crystal content of these vacuoles is released, most probably by membrane fusion to the outside of the cells. Energy-dispersive X-ray analysis (EDX), electron spectroscopic imaging, and electron energy loss spectroscopy demonstrated that Ca, O, and P are located in the intra- and extracellular needle-like crystals. From EDX spectra a Ca/P ratio of 1.3 was estimated for the intracellular structures and a Ca/P ratio of 1.5, for the extracellular material (for comparison, the Ca/P ratio in tibiae is 1.6). X-ray diffraction and quantitative infrared spectral analyses also demonstrated an increase of crystalline bone apatite along the mineralization process. In addition to the finding in vitro, the presence of intracellular needle-like crystals in vacuoles could be demonstrated in vivo in osteoblastic cells of the periosteum in tibia of day 11. The results are in favor of a novel model for mineralization by osteoblasts, in which amorphous Ca/P material is directly secreted via an exocytotic process from vacuoles of the osteoblast, deposited extracellularly, propagated into the collagen fibril matrix, and matured to hydroxyapatite.
    • Experimental selection of long-term intracellular mycobacteria.

      Vázquez, Cristina L; Lerner, Thomas R; Kasmapour, Bahram; Pei, Gang; Gronow, Achim; Bianco, Maria V; Blanco, Federico C; Geffers, Robert; Geffers, Robert; Bigi, Fabiana; et al. (2014-09)
      Some intracellular bacteria are known to cause long-term infections that last decades without compromising the viability of the host. Although of critical importance, the adaptations that intracellular bacteria undergo during this long process of residence in a host cell environment remain obscure. Here, we report a novel experimental approach to study the adaptations of mycobacteria imposed by a long-term intracellular lifestyle. Selected Mycobacterium bovis BCG through continuous culture in macrophages underwent an adaptation process leading to impaired phenolic glycolipids (PGL) synthesis, improved usage of glucose as a carbon source and accumulation of neutral lipids. These changes correlated with increased survival of mycobacteria in macrophages and mice during re-infection and also with the specific expression of stress- and survival-related genes. Our findings identify bacterial traits implicated in the establishment of long-term cellular infections and represent a tool for understanding the physiological states and the environment that bacteria face living in fluctuating intracellular environments.
    • The FbaB-type fibronectin-binding protein of Streptococcus pyogenes promotes specific invasion into endothelial cells.

      Amelung, Silva; Nerlich, Andreas; Rohde, Manfred; Spellerberg, Barbara; Cole, Jason N; Nizet, Victor; Chhatwal, Gursharan S; Talay, Susanne R; Department of Medical Microbiology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany. (2011-08)
      Invasive serotype M3 Streptococcus pyogenes are among the most frequently isolated organisms from patients suffering from invasive streptococcal disease and have the potential to invade primary human endothelial cells (EC) via a rapid and efficient mechanism. FbaB protein, the fibronectin-binding protein expressed by M3 S. pyogenes, was herein identified as a potent invasin for EC. By combining heterologous gene expression with allelic replacement, we demonstrate that FbaB is essential and sufficient to trigger EC invasion via a Rac1-dependent phagocytosis-like uptake. FbaB-mediated uptake follows the classical endocytic pathway with lysosomal destination. FbaB is demonstrated to be a streptococcal invasin exhibiting EC tropism. FbaB thus initiates a process that may contribute to the deep tissue tropism and spread of invasive S. pyogenes isolates into the vascular EC lining.
    • first detection of trimethoprim resistance determinant dfrG in Streptococcus pyogenes clinical isolates in India.

      Bergmann, René; Sagar, Vivek; Nitsche-Schmitz, D Patric; Chhatwal, Gursharan S (2012-10)
    • A flagellum-specific chaperone facilitates assembly of the core type III export apparatus of the bacterial flagellum.

      Fabiani, Florian D; Renault, Thibaud T; Peters, Britta; Dietsche, Tobias; Gálvez, Eric J C; Guse, Alina; Freier, Karen; Charpentier, Emmanuelle; Strowig, Till; Franz-Wachtel, Mirita; et al. (2017-08)
      Many bacteria move using a complex, self-assembling nanomachine, the bacterial flagellum. Biosynthesis of the flagellum depends on a flagellar-specific type III secretion system (T3SS), a protein export machine homologous to the export machinery of the virulence-associated injectisome. Six cytoplasmic (FliH/I/J/G/M/N) and seven integral-membrane proteins (FlhA/B FliF/O/P/Q/R) form the flagellar basal body and are involved in the transport of flagellar building blocks across the inner membrane in a proton motive force-dependent manner. However, how the large, multi-component transmembrane export gate complex assembles in a coordinated manner remains enigmatic. Specific for most flagellar T3SSs is the presence of FliO, a small bitopic membrane protein with a large cytoplasmic domain. The function of FliO is unknown, but homologs of FliO are found in >80% of all flagellated bacteria. Here, we demonstrate that FliO protects FliP from proteolytic degradation and promotes the formation of a stable FliP-FliR complex required for the assembly of a functional core export apparatus. We further reveal the subcellular localization of FliO by super-resolution microscopy and show that FliO is not part of the assembled flagellar basal body. In summary, our results suggest that FliO functions as a novel, flagellar T3SS-specific chaperone, which facilitates quality control and productive assembly of the core T3SS export machinery.
    • Genetic variation in group A streptococci.

      McMillan, David J; Sriprakash, Kadaba S; Chhatwal, Gursharan S; Department of Microbial Pathogenesis, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, D-38124 Braunschweig, Germany. (2007-11)
      Group A streptococcus (GAS) is responsible for a range of human diseases that vary in their clinical manifestations and severity. While numerous virulence factors have been described, the way these factors interact to promote different streptococcal diseases is less clear. In order to identify multifactorial relationships between GAS and the human host, novel high-throughput techniques such as microarrays are necessary. We have performed comparative studies using custom-designed virulence arrays to enhance our understanding of the high degree of genotypic variation that occurs in streptococci. This study has pointed to mobile genetic elements as the major agents that promote variation. Our results show that multiple combinations of genes might bring about similar clinical pictures. This adds further complexity to the intricate relationship between pathogen and host.
    • The genome sequence of Methanohalophilus mahii SLP(T) reveals differences in the energy metabolism among members of the Methanosarcinaceae inhabiting freshwater and saline environments.

      Spring, Stefan; Scheuner, Carmen; Lapidus, Alla; Lucas, Susan; Glavina Del Rio, Tijana; Tice, Hope; Copeland, Alex; Cheng, Jan-Fang; Chen, Feng; Nolan, Matt; et al. (2010)
      Methanohalophilus mahii is the type species of the genus Methanohalophilus, which currently comprises three distinct species with validly published names. Mhp. mahii represents moderately halophilic methanogenic archaea with a strictly methylotrophic metabolism. The type strain SLP(T) was isolated from hypersaline sediments collected from the southern arm of Great Salt Lake, Utah. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 2,012,424 bp genome is a single replicon with 2032 protein-coding and 63 RNA genes and part of the Genomic Encyclopedia of Bacteria and Archaea project. A comparison of the reconstructed energy metabolism in the halophilic species Mhp. mahii with other representatives of the Methanosarcinaceae reveals some interesting differences to freshwater species.
    • Genome sequence of the Antarctic rhodopsins-containing flavobacterium Gillisia limnaea type strain (R-8282T)

      Riedel, Thomas; Held, Brittany; Nolan, Matt; Lucas, Susan; Lapidus, Alla; Tice, Hope; Del Rio, Tijana Glavina; Cheng, Jan-Fang; Han, Cliff; Tapia, Roxanne; et al. (2013-02-07)
    • Genome sequence of the filamentous, gliding Thiothrix nivea neotype strain (JP2(T)).

      Lapidus, Alla; Nolan, Matt; Lucas, Susan; Glavina Del Rio, Tijana; Tice, Hope; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne; Pitluck, Sam; et al. (2011-12-31)
      Thiothrix nivea (Rabenhorst 1865) Winogradsky 1888 (Approved Lists 1980) emend. Larkin and Shinabarger 1983 is the type species of the genus Thiothrix in the family Thiotrichaceae. The species is of interest not only because of its isolated location in the yet to be genomically characterized region of the tree of life, but also because of its life-style with gliding gonidia, the multilayer sheath, rosettes, and the embedded sulfur granules. Strain JP2(T) is the neotype strain of the species which was first observed by Rabenhorst in 1865 and later reclassified by Winogradsky in 1888 into the then novel genus Thiothrix. This is the first completed (improved-high-quality-draft) genome sequence to be published of a member of the family Thiotrichaceae. The genome in its current assembly consists of 15 contigs in four scaffolds with a total of 4,691,711 bp bearing 4,542 protein-coding and 52 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
    • Genome sequence of the flexirubin-pigmented soil bacterium Niabella soli type strain (JS13-8T)

      Anderson, Iain; Munk, Christine; Lapidus, Alla; Nolan, Matt; Lucas, Susan; Tice, Hope; Glavina Del Rio, Tijana; Cheng, Jan-Fang; Han, Cliff; Tapia, Roxanne; et al. (2012)
    • Genome sequence of the moderately thermophilic halophile Flexistipes sinusarabici strain (MAS10).

      Lapidus, Alla; Chertkov, Olga; Nolan, Matt; Lucas, Susan; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne; et al. (2011-10-15)
      Flexistipes sinusarabici Fiala et al. 2000 is the type species of the genus Flexistipes in the family Deferribacteraceae. The species is of interest because of its isolated phylogenetic location in a genomically under-characterized region of the tree of life, and because of its origin from a multiply extreme environment; the Atlantis Deep brines of the Red Sea, where it had to struggle with high temperatures, high salinity, and a high concentrations of heavy metals. This is the fourth completed genome sequence to be published of a type strain of the family Deferribacteraceae. The 2,526,590 bp long genome with its 2,346 protein-coding and 53 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
    • Genome sequence of the moderately thermophilic sulfur-reducing bacterium Thermanaerovibrio velox type strain (Z-9701T) and emended description of the genus Thermanaerovibrio

      Palaniappan, Krishna; Meier-Kolthoff, Jan P.; Teshima, Hazuki; Nolan, Matt; Lapidus, Alla; Tice, Hope; Del Rio, Tijana Glavina; Cheng, Jan-Fang; Han, Cliff; Tapia, Roxanne; et al. (2014-01-06)
    • Genome sequence of the moderately thermophilic, amino-acid-degrading and sulfur-reducing bacterium Thermovirga lienii type strain (Cas60314(T)).

      Göker, Markus; Saunders, Elisabeth; Lapidus, Alla; Nolan, Matt; Lucas, Susan; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Han, Cliff; Tapia, Roxanne; et al. (2012-05-25)
      Thermovirga lienii Dahle and Birkeland 2006 is a member of the genus Thermovirga in the genomically moderately well characterized phylum 'Synergistetes'. Members of this relatively recently proposed phylum 'Synergistetes' are of interest because of their isolated phylogenetic position and their diverse habitats, e.g. from humans to oil wells. The genome of T. lienii Cas60314(T) is the fifth genome sequence (third completed) from this phylum to be published. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 1,999,646 bp long genome (including one plasmid) with its 1,914 protein-coding and 59 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
    • Genome sequence of the ocean sediment bacterium Saccharomonospora marina type strain (XMU15(T)).

      Klenk, Hans-Peter; Lu, Megan; Lucas, Susan; Lapidus, Alla; Copeland, Alex; Pitluck, Sam; Goodwin, Lynne A; Han, Cliff; Tapia, Roxanne; Brambilla, Evelyne-Marie; et al. (2012-05-25)
      Saccharomonospora marina Liu et al. 2010 is a member of the genus Saccharomonospora, in the family Pseudonocardiaceae that is poorly characterized at the genome level thus far. Members of the genus Saccharomonospora are of interest because they originate from diverse habitats, such as leaf litter, manure, compost, surface of peat, moist, over-heated grain, and ocean sediment, where they might play a role in the primary degradation of plant material by attacking hemicellulose. Organisms belonging to the genus are usually Gram-positive staining, non-acid fast, and classify among the actinomycetes. Here we describe the features of this organism, together with the complete genome sequence (permanent draft status), and annotation. The 5,965,593 bp long chromosome with its 5,727 protein-coding and 57 RNA genes was sequenced as part of the DOE funded Community Sequencing Program (CSP) 2010 at the Joint Genome Institute (JGI).
    • Genome sequence of the orange-pigmented seawater bacterium Owenweeksia hongkongensis type strain (UST20020801(T)).

      Riedel, Thomas; Held, Brittany; Nolan, Matt; Lucas, Susan; Lapidus, Alla; Tice, Hope; Del Rio, Tijana Glavina; Cheng, Jan-Fang; Han, Cliff; Tapia, Roxanne; et al. (2012-10-10)
      Lau . 2005 is the sole member of the monospecific genus in the family a poorly characterized family at the genome level thus far. This family comprises seven genera within the class . Family members are known to be psychrotolerant, rod-shaped and orange pigmented (β-carotene), typical for . For growth, seawater and complex organic nutrients are necessary. The genome of UST20020801 is only the second genome of a member of the family whose sequence has been deciphered. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,000,057 bp long chromosome with its 3,518 protein-coding and 45 RNA genes is a part of the project.
    • Genome sequence of the soil bacterium Saccharomonospora azurea type strain (NA-128(T)).

      Klenk, Hans-Peter; Held, Brittany; Lucas, Susan; Lapidus, Alla; Copeland, Alex; Hammon, Nancy; Pitluck, Sam; Goodwin, Lynne A; Han, Cliff; Tapia, Roxanne; et al. (2012-05-25)
      Saccharomonospora azurea Runmao et al. 1987 is a member of the genus Saccharomonospora, which is in the family Pseudonocardiaceae and thus far poorly characterized genomically. Members of the genus Saccharomonospora are of interest because they originate from diverse habitats, such as leaf litter, manure, compost, the surface of peat, and moist and over-heated grain, and may play a role in the primary degradation of plant material by attacking hemicellulose. Next to S. viridis, S. azurea is only the second member in the genus Saccharomonospora for which a completely sequenced type strain genome will be published. Here we describe the features of this organism, together with the complete genome sequence with project status 'Improved high quality draft', and the annotation. The 4,763,832 bp long chromosome with its 4,472 protein-coding and 58 RNA genes was sequenced as part of the DOE funded Community Sequencing Program (CSP) 2010 at the Joint Genome Institute (JGI).