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Full-Text Articles in Life Sciences

Ppld Is A De-N-Acetylase Of The Cell Wall Linkage Unit Of Streptococcal Rhamnopolysaccharides, Jeffrey S. Rush, Prakash Parajuli, Alessandro Ruda, Jian Li, Amol Arunrao Pohane, Svetlana Zamakhaeva, Mohammad M. Rahman, Jennifer C. Chang, Artemis Gogos, Cameron W. Kenner, Gérard Lambeau, Michael J. Federle, Konstantin V. Korotkov, Göran Widmalm, Natalia Korotkova Feb 2022

Ppld Is A De-N-Acetylase Of The Cell Wall Linkage Unit Of Streptococcal Rhamnopolysaccharides, Jeffrey S. Rush, Prakash Parajuli, Alessandro Ruda, Jian Li, Amol Arunrao Pohane, Svetlana Zamakhaeva, Mohammad M. Rahman, Jennifer C. Chang, Artemis Gogos, Cameron W. Kenner, Gérard Lambeau, Michael J. Federle, Konstantin V. Korotkov, Göran Widmalm, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

The cell wall of the human bacterial pathogen Group A Streptococcus (GAS) consists of peptidoglycan decorated with the Lancefield group A carbohydrate (GAC). GAC is a promising target for the development of GAS vaccines. In this study, employing chemical, compositional, and NMR methods, we show that GAC is attached to peptidoglycan via glucosamine 1-phosphate. This structural feature makes the GAC-peptidoglycan linkage highly sensitive to cleavage by nitrous acid and resistant to mild acid conditions. Using this characteristic of the GAS cell wall, we identify PplD as a protein required for deacetylation of linkage N-acetylglucosamine (GlcNAc). X-ray structural analysis indicates …


Bioprospecting Deep-Sea Actinobacteria For Novel Anti-Infective Natural Products, Dongbo Xu, Linna Han, Chunhui Li, Qi Cao, Duolong Zhu, Nolan H. Barrett, Dedra Harmody, Jing Chen, Haining Zhu, Peter J. Mccarthy, Xingmin Sun, Guojun Wang Apr 2018

Bioprospecting Deep-Sea Actinobacteria For Novel Anti-Infective Natural Products, Dongbo Xu, Linna Han, Chunhui Li, Qi Cao, Duolong Zhu, Nolan H. Barrett, Dedra Harmody, Jing Chen, Haining Zhu, Peter J. Mccarthy, Xingmin Sun, Guojun Wang

Molecular and Cellular Biochemistry Faculty Publications

The global prevalence of drug resistance has created an urgent need for the discovery of novel anti-infective drugs. The major source of antibiotics in current clinical practice is terrestrial actinobacteria; the less-exploited deep-sea actinobacteria may serve as an unprecedented source of novel natural products. In this study, we evaluated 50 actinobacteria strains derived from diverse deep water sponges and environmental niches for their anti-microbial activities against a panel of pathogens including Candida albicans, Clostridium difficile, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA), and Pseudomonas aeruginosa. More than half of the tested strains (27) were identified as …


Transmembrane Domains Of Highly Pathogenic Viral Fusion Proteins Exhibit Trimeric Association In Vitro, Stacy R. Webb, Stacy E. Smith, Michael G. Fried, Rebecca Ellis Dutch Apr 2018

Transmembrane Domains Of Highly Pathogenic Viral Fusion Proteins Exhibit Trimeric Association In Vitro, Stacy R. Webb, Stacy E. Smith, Michael G. Fried, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Enveloped viruses require viral fusion proteins to promote fusion of the viral envelope with a target cell membrane. To drive fusion, these proteins undergo large conformational changes that must occur at the right place and at the right time. Understanding the elements which control the stability of the prefusion state and the initiation of conformational changes is key to understanding the function of these important proteins. The construction of mutations in the fusion protein transmembrane domains (TMDs) or the replacement of these domains with lipid anchors has implicated the TMD in the fusion process. However, the structural and molecular details …


Human Metapneumovirus Induces Formation Of Inclusion Bodies For Efficient Genome Replication And Transcription, Nicolás P. Cifuentes-Muñoz, Jean Branttie, Kerri Beth Slaughter, Rebecca Ellis Dutch Dec 2017

Human Metapneumovirus Induces Formation Of Inclusion Bodies For Efficient Genome Replication And Transcription, Nicolás P. Cifuentes-Muñoz, Jean Branttie, Kerri Beth Slaughter, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Human metapneumovirus (HMPV) causes significant upper and lower respiratory disease in all age groups worldwide. The virus possesses a negative-sense single-stranded RNA genome of approximately 13.3 kb encapsidated by multiple copies of the nucleoprotein (N), giving rise to helical nucleocapsids. In addition, copies of the phosphoprotein (P) and the large RNA polymerase (L) decorate the viral nucleocapsids. After viral attachment, endocytosis, and fusion mediated by the viral glycoproteins, HMPV nucleocapsids are released into the cell cytoplasm. To visualize the subsequent steps of genome transcription and replication, a fluorescence in situ hybridization (FISH) protocol was established to detect different viral RNA …


The Molecular Mechanism Of N-Acetylglucosamine Side-Chain Attachment To The Lancefield Group A Carbohydrate In Streptococcus Pyogenes, Jeffrey Rush, Rebecca J. Edgar, Pan Deng, Jing Chen, Haining Zhu, Nina M. Van Sorge, Andrew J. Morris, Konstantin V. Korotkov, Natalia Korotkova Oct 2017

The Molecular Mechanism Of N-Acetylglucosamine Side-Chain Attachment To The Lancefield Group A Carbohydrate In Streptococcus Pyogenes, Jeffrey Rush, Rebecca J. Edgar, Pan Deng, Jing Chen, Haining Zhu, Nina M. Van Sorge, Andrew J. Morris, Konstantin V. Korotkov, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

In many Lactobacillales species (i.e. lactic acid bacteria), peptidoglycan is decorated by polyrhamnose polysaccharides that are critical for cell envelope integrity and cell shape and also represent key antigenic determinants. Despite the biological importance of these polysaccharides, their biosynthetic pathways have received limited attention. The important human pathogen, Streptococcus pyogenes, synthesizes a key antigenic surface polymer, the Lancefield group A carbohydrate (GAC). GAC is covalently attached to peptidoglycan and consists of a polyrhamnose polymer, with N-acetylglucosamine (GlcNAc) side chains, which is an essential virulence determinant. The molecular details of the mechanism of polyrhamnose modification with GlcNAc are …


Peptide Inhibitors Targeting The Neisseria Gonorrhoeae Pivotal Anaerobic Respiration Factor Ania, Aleksandra E. Sikora, Robert H. Mills, Jacob V. Weber, Adel Hamza, Bryan W. Passow, Andrew Romaine, Zachary A. Williamson, Robert W. Reed, Ryszard A. Zielke, Konstantin V. Korotkov Aug 2017

Peptide Inhibitors Targeting The Neisseria Gonorrhoeae Pivotal Anaerobic Respiration Factor Ania, Aleksandra E. Sikora, Robert H. Mills, Jacob V. Weber, Adel Hamza, Bryan W. Passow, Andrew Romaine, Zachary A. Williamson, Robert W. Reed, Ryszard A. Zielke, Konstantin V. Korotkov

Molecular and Cellular Biochemistry Faculty Publications

Neisseria gonorrhoeae causes the sexually transmitted infection gonorrhea, which is highly prevalent worldwide and has a major impact on reproductive and neonatal health. The superbug status of N. gonorrhoeae necessitates the development of drugs with different mechanisms of action. Here, we focused on targeting the nitrite reductase AniA, which is a pivotal component of N. gonorrhoeae anaerobic respiration and biofilm formation. Our studies showed that gonococci expressing AniA containing the altered catalytic residues D137A and H280A failed to grow under anaerobic conditions, demonstrating that the nitrite reductase function is essential. To facilitate the pharmacological targeting of AniA, new crystal structures …


Mutations In The Transmembrane Domain And Cytoplasmic Tail Of Hendra Virus Fusion Protein Disrupt Virus-Like-Particle Assembly, Nicolás P. Cifuentes-Muñoz, Weina Sun, Greeshma Ray, Phuong Tieu Schmitt, Stacy Webb, Kathleen Gibson, Rebecca Ellis Dutch, Anthony P. Schmitt Jul 2017

Mutations In The Transmembrane Domain And Cytoplasmic Tail Of Hendra Virus Fusion Protein Disrupt Virus-Like-Particle Assembly, Nicolás P. Cifuentes-Muñoz, Weina Sun, Greeshma Ray, Phuong Tieu Schmitt, Stacy Webb, Kathleen Gibson, Rebecca Ellis Dutch, Anthony P. Schmitt

Molecular and Cellular Biochemistry Faculty Publications

Hendra virus (HeV) is a zoonotic paramyxovirus that causes deadly illness in horses and humans. An intriguing feature of HeV is the utilization of endosomal protease for activation of the viral fusion protein (F). Here we investigated how endosomal F trafficking affects HeV assembly. We found that the HeV matrix (M) and F proteins each induced particle release when they were expressed alone but that their coexpression led to coordinated assembly of virus-like particles (VLPs) that were morphologically and physically distinct from M-only or F-only VLPs. Mutations to the F protein transmembrane domain or cytoplasmic tail that disrupted endocytic trafficking …


Genetic Metabolic Complementation Establishes A Requirement For Gdp-Fucose In Leishmania, Hongjie Guo, Natalia M. Novozhilova, Giulia Bandini, Salvatore J. Turco, Michael A. L. Ferguson, Stephen M. Beverley May 2017

Genetic Metabolic Complementation Establishes A Requirement For Gdp-Fucose In Leishmania, Hongjie Guo, Natalia M. Novozhilova, Giulia Bandini, Salvatore J. Turco, Michael A. L. Ferguson, Stephen M. Beverley

Molecular and Cellular Biochemistry Faculty Publications

To survive in its sand fly vector, the trypanosomatid protozoan parasite Leishmania first attaches to the midgut to avoid excretion, but eventually it must detach for transmission by the next bite. In Leishmania major strain Friedlin, this is controlled by modifications of the stage-specific adhesin lipophosphoglycan (LPG). During differentiation to infective metacyclics, d-arabinopyranose (d-Arap) caps the LPG side-chain galactose residues, blocking interaction with the midgut lectin PpGalec, thereby leading to parasite detachment and transmission. Previously, we characterized two closely related L. major genes (FKP40 and AFKP80) encoding bifunctional proteins with kinase/pyrophosphorylase activities required for salvage and …


Functional And Structural Studies On The Neisseria Gonorrhoeae Gmha, The First Enzyme In The Glycero-Manno-Heptose Biosynthesis Pathways, Demonstrate A Critical Role In Lipooligosaccharide Synthesis And Gonococcal Viability, Igor H. Wierzbicki, Ryszard A. Zielke, Konstantin V. Korotkov, Aleksandra E. Sikora Jan 2017

Functional And Structural Studies On The Neisseria Gonorrhoeae Gmha, The First Enzyme In The Glycero-Manno-Heptose Biosynthesis Pathways, Demonstrate A Critical Role In Lipooligosaccharide Synthesis And Gonococcal Viability, Igor H. Wierzbicki, Ryszard A. Zielke, Konstantin V. Korotkov, Aleksandra E. Sikora

Molecular and Cellular Biochemistry Faculty Publications

Sedoheptulose-7-phosphate isomerase, GmhA, is the first enzyme in the biosynthesis of nucleotide-activated-glycero-manno-heptoses and an attractive, yet underexploited, target for development of broad-spectrum antibiotics. We demonstrated that GmhA homologs in Neisseria gonorrhoeae and N. meningitidis (hereafter called GmhAGC and GmhANM, respectively) were interchangeable proteins essential for lipooligosaccharide (LOS) synthesis, and their depletion had adverse effects on neisserial viability. In contrast, the Escherichia coli ortholog failed to complement GmhAGC depletion. Furthermore, we showed that GmhAGC is a cytoplasmic enzyme with induced expression at mid-logarithmic phase, upon iron deprivation and anaerobiosis, and conserved in contemporary gonococcal …


Mycosins Are Required For The Stabilization Of The Esx-1 And Esx-5 Type Vii Secretion Membrane Complexes, Vincent J. C. Van Winden, Roy Ummels, Sander R. Piersma, Connie R. Jiménez, Konstantin V. Korotkov, Wilbert Bitter, Edith N. G. Houben Oct 2016

Mycosins Are Required For The Stabilization Of The Esx-1 And Esx-5 Type Vii Secretion Membrane Complexes, Vincent J. C. Van Winden, Roy Ummels, Sander R. Piersma, Connie R. Jiménez, Konstantin V. Korotkov, Wilbert Bitter, Edith N. G. Houben

Molecular and Cellular Biochemistry Faculty Publications

ABSTRACT Pathogenic mycobacteria contain up to five type VII secretion (T7S) systems, ESX-1 to ESX-5. One of the conserved T7S components is the serine protease mycosin (MycP). Strikingly, whereas MycP is essential for secretion, the protease activity of MycP1 in Mycobacterium tuberculosis has been shown to be dispensable for secretion. The essential role of MycP therefore remains unclear. Here we show that MycP1 and MycP5 of M. marinum have similar phenotypes, confirming that MycP has a second unknown function that is essential for its T7S system. To investigate whether this role is related to proper functioning of …


Spyb, A Small Heme-Binding Protein, Affects The Composition Of The Cell Wall In Streptococcus Pyogenes, Rebecca J. Edgar, Jing Chen, Sashi Kant, Elena Rechkina, Jeffrey S. Rush, Lennart S. Forsberg, Bernhard Jaehrig, Parastoo Azadi, Veronika Tchesnokova, Evgeni V. Sokurenko, Haining Zhu, Konstantin V. Korotkov, Vijay Pancholi, Natalia Korotkova Oct 2016

Spyb, A Small Heme-Binding Protein, Affects The Composition Of The Cell Wall In Streptococcus Pyogenes, Rebecca J. Edgar, Jing Chen, Sashi Kant, Elena Rechkina, Jeffrey S. Rush, Lennart S. Forsberg, Bernhard Jaehrig, Parastoo Azadi, Veronika Tchesnokova, Evgeni V. Sokurenko, Haining Zhu, Konstantin V. Korotkov, Vijay Pancholi, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

Streptococcus pyogenes (Group A Streptococcus or GAS) is a hemolytic human pathogen associated with a wide variety of infections ranging from minor skin and throat infections to life-threatening invasive diseases. The cell wall of GAS consists of peptidoglycan sacculus decorated with a carbohydrate comprising a polyrhamnose backbone with immunodominant N-acetylglucosamine side-chains. All GAS genomes contain the spyBA operon, which encodes a 35-amino-acid membrane protein SpyB, and a membrane-bound C3-like ADP-ribosyltransferase SpyA. In this study, we addressed the function of SpyB in GAS. Phenotypic analysis of a spyB deletion mutant revealed increased bacterial aggregation, and reduced sensitivity to β-lactams of the …


Inhibition Of Human Metapneumovirus Binding To Heparan Sulfate Blocks Infection In Human Lung Cells And Airway Tissues, Edita M. Klimyte, Stacy E. Smith, Pasqua Oreste, David Lembo, Rebecca Ellis Dutch Oct 2016

Inhibition Of Human Metapneumovirus Binding To Heparan Sulfate Blocks Infection In Human Lung Cells And Airway Tissues, Edita M. Klimyte, Stacy E. Smith, Pasqua Oreste, David Lembo, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Human metapneumovirus (HMPV), a recently discovered paramyxovirus, infects nearly 100% of the world population and causes severe respiratory disease in infants, the elderly, and immunocompromised patients. We previously showed that HMPV binds heparan sulfate proteoglycans (HSPGs) and that HMPV binding requires only the viral fusion (F) protein. To characterize the features of this interaction critical for HMPV binding and the role of this interaction in infection in relevant models, we utilized sulfated polysaccharides, heparan sulfate mimetics, and occluding compounds. Iota-carrageenan demonstrated potent anti-HMPV activity by inhibiting binding to lung cells mediated by the F protein. Furthermore, analysis of a minilibrary …