scholarly journals “Salmonella, meet mycobacteria.”

2019 ◽  
Vol 216 (4) ◽  
pp. 721-722 ◽  
Author(s):  
Stephanie R. Lovell-Read ◽  
Luiz Pedro Sorio de Carvalho
Keyword(s):  
Cell Wall ◽  
New Family ◽  
Cord Factor ◽  
Salmonella Serovars

In this issue of JEM, Reinink et al. (https://doi.org/10.1084/jem.20181812) use comparative lipidomics to identify a new family of trehalose-containing cell wall lipids that are enriched in virulent Salmonella serovars. These lipids are structurally related to the important mycobacterial immunogen cord factor.

scholarly journals The structure of Rv3717 reveals a novel amidase fromMycobacterium tuberculosis

2013 ◽  
Vol 69 (12) ◽  
pp. 2543-2554 ◽  
Author(s):  
Atul Kumar ◽  
Sanjiv Kumar ◽  
Dilip Kumar ◽  
Arpit Mishra ◽  
Rikeshwer P. Dewangan ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bartonella Henselae ◽  
General Mechanism ◽  
Isolation And Identification ◽  
Cell Wall Binding ◽  
New Family ◽  
A Cell ◽  
Sad Phasing ◽  
Cell Wall Binding Domain ◽  
Net Positive Charge

BacterialN-acetylmuramoyl-L-alanine amidases are cell-wall hydrolases that hydrolyze the bond betweenN-acetylmuramic acid and L-alanine in cell-wall glycopeptides. Rv3717 ofMycobacterium tuberculosishas been identified as a unique autolysin that lacks a cell-wall-binding domain (CBD) and its structure has been determined to 1.7 Å resolution by the Pt-SAD phasing method. Rv3717 possesses an α/β-fold and is a zinc-dependent hydrolase. The structure reveals a short flexible hairpin turn that partially occludes the active site and may be involved in autoregulation. This type of autoregulation of activity of PG hydrolases has been observed inBartonella henselaeamidase (AmiB) and may be a general mechanism used by some of the redundant amidases to regulate cell-wall hydrolase activity in bacteria. Rv3717 utilizes its net positive charge for substrate binding and exhibits activity towards a broad spectrum of substrate cell walls. The enzymatic activity of Rv3717 was confirmed by isolation and identification of its enzymatic products by LC/MS. These studies indicate that Rv3717, anN-acetylmuramoyl-L-alanine amidase fromM. tuberculosis, represents a new family of lytic amidases that do not have a separate CBD and are regulated conformationally.

scholarly journals Mincle is a long sought receptor for mycobacterial cord factor

2009 ◽  
Vol 206 (13) ◽  
pp. 2865-2868 ◽  
Author(s):  
Isamu Matsunaga ◽  
D. Branch Moody
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Research Effort ◽  
Therapeutic Tool ◽  
Cord Factor ◽  
Insight Into

Mycobacterium tuberculosis is a leading killer worldwide, yet the adjuvancy of its cell wall has proven to be a valuable therapeutic tool for vaccination and immunotherapy. Much research effort has focused on the mycobacterial glycolipid trehalose-6,6’-dimycolate (TDM), a potent immunostimulant that is also known as cord factor. Now, the identification of the monocyte-inducible C-type lectin (Mincle) as an essential receptor for TDM provides new insight into the formation of the characteristic granulomas in tuberculosis and an avenue for rational adjuvant design.

scholarly journals Discovery of Salmonella trehalose phospholipids reveals functional convergence with mycobacteria

2019 ◽  
Vol 216 (4) ◽  
pp. 757-771 ◽  
Author(s):  
Peter Reinink ◽  
Jeffrey Buter ◽  
Vivek K. Mishra ◽  
Eri Ishikawa ◽  
Tan-Yun Cheng ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacterial Species ◽  
Specific Cell ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Trehalose Dimycolate ◽  
Functional Convergence ◽  
Cord Factor ◽  
Cardiolipin Synthase ◽  
Activating Receptor

Salmonella species are among the world’s most prevalent pathogens. Because the cell wall interfaces with the host, we designed a lipidomics approach to reveal pathogen-specific cell wall compounds. Among the molecules differentially expressed between Salmonella Paratyphi and S. Typhi, we focused on lipids that are enriched in S. Typhi, because it causes typhoid fever. We discovered a previously unknown family of trehalose phospholipids, 6,6′-diphosphatidyltrehalose (diPT) and 6-phosphatidyltrehalose (PT). Cardiolipin synthase B (ClsB) is essential for PT and diPT but not for cardiolipin biosynthesis. Chemotyping outperformed clsB homology analysis in evaluating synthesis of diPT. DiPT is restricted to a subset of Gram-negative bacteria: large amounts are produced by S. Typhi, lower amounts by other pathogens, and variable amounts by Escherichia coli strains. DiPT activates Mincle, a macrophage activating receptor that also recognizes mycobacterial cord factor (6,6′-trehalose dimycolate). Thus, Gram-negative bacteria show convergent function with mycobacteria. Overall, we discovered a previously unknown immunostimulant that is selectively expressed among medically important bacterial species.

scholarly journals Environmental, Biogeographic, and Biochemical Patterns of Archaea of the Family Ferroplasmaceae

2011 ◽  
Vol 77 (15) ◽  
pp. 5071-5078 ◽  
Author(s):  
Olga V. Golyshina
Keyword(s):  
Cell Wall ◽  
Research Progress ◽  
Current Status ◽  
Content Type ◽  
Research Areas ◽  
Physiological Diversity ◽  
New Family ◽  
The Family ◽  
Acidophilic Archaea

ABSTRACTAbout 10 years ago, a new family of cell wall-deficient, iron-oxidizing archaea,Ferroplasmaceae, within the large archaeal phylumEuryarchaeota, was described. In this minireview, I summarize the research progress achieved since then and report on the current status of taxonomy, biogeography, physiological diversity, biochemistry, and other research areas involving this exciting group of acidophilic archaea.

scholarly journals Biosynthesis and Virulent Behavior of Lipids Produced by Mycobacterium tuberculosis: LAM and Cord Factor: An Overview

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Rajni ◽  
Nisha Rao ◽  
Laxman S. Meena
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Host Cell ◽  
Phosphatidyl Inositol ◽  
Polymorphonuclear Neutrophils ◽  
Host Cells ◽  
Wall Structure ◽  
Trehalose Dimycolate ◽  
Cell Immunity ◽  
Cord Factor

Mycobacterium tuberculosis is the causative agent of tuberculosis disease, which has developed a myriad of exceptional features contributing to its survival within the hostile environment of host cell. Unique cell wall structure with high lipid content plays an imperative role in the pathogenicity of mycobacteria. Cell wall components of MTB such as lipoarabinomannan and Trehalose dimycolate (cord factor) are virulent in nature apart from its virulence genes. Virulent effect of these factors on host cells reduces host cell immunity. LAM has been known to inhibit phagosome maturation by inhibiting the Ca2+/calmodulin phosphatidyl inositol-3-kinase hvps34 pathways. Moreover, TDM (Trehalose dimycolate) also inhibits fusion between phospholipid vesicles and migration of polymorphonuclear neutrophils. The objective of this paper is to understand the virulence of LAM and cord factor on host cell which might be helpful to design an effective drug against tuberculosis.

scholarly journals Thermosporothrix hazakensis gen. nov., sp. nov., isolated from compost, description of Thermosporotrichaceae fam. nov. within the class Ktedonobacteria Cavaletti et al. 2007 and emended description of the class Ktedonobacteria

2010 ◽  
Vol 60 (8) ◽  
pp. 1794-1801 ◽  
Author(s):  
Shuhei Yabe ◽  
Yoshifumi Aiba ◽  
Yasuteru Sakai ◽  
Masaru Hazaka ◽  
Akira Yokota
Keyword(s):  
Cell Wall ◽  
Major Fatty Acid ◽  
Molar Ratio ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Optimum Growth ◽  
New Family ◽  
Emended Description ◽  
Novel Genus And Species ◽  
Ph Range

We isolated from compost an aerobic, thermophilic, Gram-stain-positive, spore-forming bacterium that formed branched vegetative and aerial mycelia. This strain, designated SK20-1T, grew at 31–58 °C, with optimum growth at 50 °C, while no growth was observed below 28 or above 60 °C. The pH range for growth was 5.4–8.7, with optimum growth at pH 7.0, while no growth was observed below pH 5.0 or above pH 9.1. Strain SK20-1T was able to hydrolyse polysaccharides such as cellulose, xylan and chitin. The DNA G+C content was 54.0 mol%. The major fatty acid was iso-C17 : 0 and the major menaquinone was MK-9(H2). The cell wall contained glutamic acid, serine, alanine and ornithine in a molar ratio of 1.00 : 1.07 : 2.64 : 0.83. The polar lipids consisted of phosphatidylinositol, phosphatidylinositol mannosides, phosphatidylglycerol, diphosphatidylglycerol and an unknown glycolipid. Cell-wall sugars were rhamnose and mannose. Detailed phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SK20-1T belongs to the class Ktedonobacteria, and that the strain is most closely related to Ktedonobacter racemifer SOSP1-21T (88.5 %). On the basis of its phenotypic features and phylogenetic position, we propose that SK20-1T represents a novel genus and species, Thermosporothrix hazakensis gen. nov., sp. nov., within the new family Thermosporotrichaceae fam. nov. The type strain of Thermosporothrix hazakensis is strain SK20-1T (=JCM 16142T =ATCC BAA-1881T). In addition, we propose an emended description of the class Ktedonobacteria to classify the class in the phylum Chloroflexi.

Suppression of an ascitic rat hepatoma with cord factor and nocardia cell wall skeleton in squalene emulsions

1980 ◽  
Vol 16 (12) ◽  
pp. 1645-1647 ◽  
Author(s):  
Malcolm V. Pimm ◽  
Robert W. Baldwin ◽  
Edgar Lederer
Keyword(s):  
Cell Wall ◽  
Cord Factor ◽  
Rat Hepatoma

scholarly journals A New Family of Capsule Polymerases Generates Teichoic Acid-Like Capsule Polymers in Gram-Negative Pathogens

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Christa Litschko ◽  
Davide Oldrini ◽  
Insa Budde ◽  
Monika Berger ◽  
Jochen Meens ◽  
...  
Keyword(s):  
Cell Wall ◽  
Teichoic Acid ◽  
Animal Husbandry ◽  
Type I ◽  
Gram Positive ◽  
Gram Negative ◽  
Content Type ◽  
New Family ◽  
Animal Pathogens ◽  
Conventional Production

ABSTRACTGroup 2 capsule polymers represent crucial virulence factors of Gram-negative pathogenic bacteria. They are synthesized by enzymes called capsule polymerases. In this report, we describe a new family of polymerases that combine glycosyltransferase and hexose- and polyol-phosphate transferase activity to generate complex poly(oligosaccharide phosphate) and poly(glycosylpolyol phosphate) polymers, the latter of which display similarity to wall teichoic acid (WTA), a cell wall component of Gram-positive bacteria. Using modeling and multiple-sequence alignment, we showed homology between the predicted polymerase domains and WTA type I biosynthesis enzymes, creating a link between Gram-negative and Gram-positive cell wall biosynthesis processes. The polymerases of the new family are highly abundant and found in a variety of capsule-expressing pathogens such asNeisseria meningitidis,Actinobacillus pleuropneumoniae,Haemophilus influenzae,Bibersteinia trehalosi, andEscherichia coliwith both human and animal hosts. Five representative candidates were purified, their activities were confirmed using nuclear magnetic resonance (NMR) spectroscopy, and their predicted folds were validated by site-directed mutagenesis.IMPORTANCEBacterial capsules play an important role in the interaction between a pathogen and the immune system of its host. During the last decade, capsule polymerases have become attractive tools for the production of capsule polymers applied as antigens in glycoconjugate vaccine formulations. Conventional production of glycoconjugate vaccines requires the cultivation of the pathogen and thus the highest biosafety standards, leading to tremendous costs. With regard to animal husbandry, where vaccines could avoid the extensive use of antibiotics, conventional production is not sufficiently cost-effective. In contrast, enzymatic synthesis of capsule polymers is pathogen-free and fast, offers high stereo- and regioselectivity, and works with high efficacy. The new capsule polymerase family described here vastly increases the toolbox of enzymes available for biotechnology purposes. Representatives are abundantly found in human pathogens but also in animal pathogens, paving the way for the exploitation of polymerases for the development of a new generation of vaccines for animal husbandry.

scholarly journals CORYNEBACTERIUM: FEATURES OF THE STRUCTURE OF THE BACTERIAL CELL

2017 ◽  
pp. 107-114
Author(s):  
G. G. Kharseeva ◽  
N. A. Voronina
Keyword(s):  
Cell Wall ◽  
Cytoplasmic Membrane ◽  
Molecular Genetic ◽  
Surface Proteins ◽  
Bacterial Cells ◽  
Closely Related Species ◽  
Wall Structures ◽  
Cord Factor ◽  
And Function ◽  
Structure And Functions

In a review of the features of the bacterial cells are Corynebacterium structure: characterized by an upper layer, highly organized cell wall, cytoplasmic membrane, cytoplasm, nucleoid. Described in detail the structure of the upper layer containing pili (fimbriae), microcapsule surface proteins - PS-2, DIP1281, 67-72r protein (hemagglutinin), porins, sialidase (neuraminidase). These components are the ability to initiate a serial of Corynebacterium work with the host cell, followed by colonization. It submitted a detailed description of the structure and functions of cell wall structures - cord factor, which is a second barrier permeability; arabinogalactan, peptidoglycan, lipomannan and lipoarabinomannan. The structure and function of the cytoplasmic membrane as the main diffusion barrier cell cytoplasm and the genome of Corynebacterium. Presented different molecular genetic methods for the identification and differentiation of closely related species of Corynebacterium.

scholarly journals Fungal GH25 muramidases: New family members with applications in animal nutrition and a crystal structure at 0.78Å resolution

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248190
Author(s):  
Olga V. Moroz ◽  
Elena Blagova ◽  
Edward Taylor ◽  
Johan P. Turkenburg ◽  
Lars K. Skov ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Cell Wall ◽  
Glycoside Hydrolase ◽  
Animal Feed ◽  
Commercial Application ◽  
Animal Nutrition ◽  
Suitable Candidate ◽  
New Family ◽  
Sequence Search ◽  
Bacterial Peptidoglycan

Muramidases/lysozymes hydrolyse the peptidoglycan component of the bacterial cell wall. They are found in many of the glycoside hydrolase (GH) families. Family GH25 contains muramidases/lysozymes, known as CH type lysozymes, as they were initially discovered in the Chalaropsis species of fungus. The characterized enzymes from GH25 exhibit both β-1,4-N-acetyl- and β-1,4-N,6-O-diacetylmuramidase activities, cleaving the β-1,4-glycosidic bond between N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) moieties in the carbohydrate backbone of bacterial peptidoglycan. Here, a set of fungal GH25 muramidases were identified from a sequence search, cloned and expressed and screened for their ability to digest bacterial peptidoglycan, to be used in a commercial application in chicken feed. The screen identified the enzyme from Acremonium alcalophilum JCM 736 as a suitable candidate for this purpose and its relevant biochemical and biophysical and properties are described. We report the crystal structure of the A. alcalophilum enzyme at atomic, 0.78 Å resolution, together with that of its homologue from Trichobolus zukalii at 1.4 Å, and compare these with the structures of homologues. GH25 enzymes offer a new solution in animal feed applications such as for processing bacterial debris in the animal gut.

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