Biomaterial Database

Structure and function of the Salmonella Typhi chimaeric A(2)B(5) typhoid toxin. 2013

Jeongmin Song, and Xiang Gao, and Jorge E Galán

Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06536, USA.

Salmonella enterica serovar Typhi (S. Typhi) differs from most other salmonellae in that it causes a life-threatening systemic infection known as typhoid fever. The molecular bases for its unique clinical presentation are unknown. Here we find that the systemic administration of typhoid toxin, a unique virulence factor of S. Typhi, reproduces many of the acute symptoms of typhoid fever in an animal model. We identify specific carbohydrate moieties on specific surface glycoproteins that serve as receptors for typhoid toxin, which explains its broad cell target specificity. We present the atomic structure of typhoid toxin, which shows an unprecedented A2B5 organization with two covalently linked A subunits non-covalently associated to a pentameric B subunit. The structure provides insight into the toxin's receptor-binding specificity and delivery mechanisms and reveals how the activities of two powerful toxins have been co-opted into a single, unique toxin that can induce many of the symptoms characteristic of typhoid fever. These findings may lead to the development of potentially life-saving therapeutics against typhoid fever.

UI	MeSH Term	Description	Entries
D008562	Membrane Glycoproteins	Glycoproteins found on the membrane or surface of cells.	Cell Surface Glycoproteins,Surface Glycoproteins,Cell Surface Glycoprotein,Membrane Glycoprotein,Surface Glycoprotein,Glycoprotein, Cell Surface,Glycoprotein, Membrane,Glycoprotein, Surface,Glycoproteins, Cell Surface,Glycoproteins, Membrane,Glycoproteins, Surface,Surface Glycoprotein, Cell,Surface Glycoproteins, Cell
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D004731	Endotoxins	Toxins closely associated with the living cytoplasm or cell wall of certain microorganisms, which do not readily diffuse into the culture medium, but are released upon lysis of the cells.	Endotoxin
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012485	Salmonella typhi	A serotype of SALMONELLA ENTERICA which is the etiologic agent of TYPHOID FEVER.	Salmonella enterica serovar Typhi,Salmonella typhosa
D012795	Sialoglycoproteins	Glycoproteins which contain sialic acid as one of their carbohydrates. They are often found on or in the cell or tissue membranes and participate in a variety of biological activities.	Polysialoglycoprotein,Sialoglycopeptide,Sialoglycopeptides,Sialoglycoprotein,Sialoprotein,Sialoproteins,Polysialoglycoproteins
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D014435	Typhoid Fever	An acute systemic febrile infection caused by SALMONELLA TYPHI, a serotype of SALMONELLA ENTERICA.	Enteric Fever,Typhus, Abdominal,Salmonella typhi Infection,Typhoid,Abdominal Typhus,Enteric Fevers,Fever, Enteric,Fever, Typhoid,Fevers, Enteric,Fevers, Typhoid,Infection, Salmonella typhi,Infections, Salmonella typhi,Salmonella typhi Infections,Typhoid Fevers,Typhoids