Biomaterial Database

The major capsid protein of the lipid-containing bacteriophage PR4 is the precursor of two other capsid proteins. 1994

H Myung, and T Vanden Boom, and J E Cronan

Department of Microbiology, University of Illinois, Urbana 61801.

We report that capsid proteins P16 and P18 of bacteriophage PR4 are synthesized by post-translational processing of a portion of the major capsid protein, P2. A polyclonal antibody raised against purified P2 reacted with P16 and P18 as well as with P2. A monoclonal antibody reacted with both P2 and P18. The amino acid sequences of the N-termini of P2 and P18 exactly matched, indicating that P18 is derived from the N-terminal segment of P2. These data were confirmed by the analysis of the proteins encoded by various nonsense and missense P2 mutants. The 3129-bp MnlI-C fragment of the PR4 genome was shown to encode P2. The nucleotide sequence of this fragment was obtained and a single continuous ORF was found to encode P2, thus excluding introns and transcript processing in the production of P16 and P18. The DNA segment contained eight ORFs sized > 200 bp and the genes encoding proteins P6 and P6A as well as P2 were mapped by marker rescue analysis. We also report the isolation and characterization of a new class of P2 missense mutants.

UI	MeSH Term	Description	Entries
D008563	Membrane Lipids	Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.	Cell Membrane Lipid,Cell Membrane Lipids,Membrane Lipid,Lipid, Cell Membrane,Lipid, Membrane,Lipids, Cell Membrane,Lipids, Membrane,Membrane Lipid, Cell,Membrane Lipids, Cell
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
D010743	Phospholipids	Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.	Phosphatides,Phospholipid
D002213	Capsid	The outer protein protective shell of a virus, which protects the viral nucleic acid. Capsids are composed of repeating units (capsomers or capsomeres) of CAPSID PROTEINS which when assembled together form either an icosahedral or helical shape.	Procapsid,Prohead,Capsids,Procapsids,Proheads
D003090	Coliphages	Viruses whose host is Escherichia coli.	Escherichia coli Phages,Coliphage,Escherichia coli Phage,Phage, Escherichia coli,Phages, Escherichia coli
D005814	Genes, Viral	The functional hereditary units of VIRUSES.	Viral Genes,Gene, Viral,Viral Gene
D012483	Salmonella Phages	Viruses whose host is Salmonella. A frequently encountered Salmonella phage is BACTERIOPHAGE P22.	Salmonella Bacteriophages,Bacteriophage, Salmonella,Bacteriophages, Salmonella,Salmonella Bacteriophage,Salmonella Phage
D015678	Viral Structural Proteins	Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).	Polypeptide VP1, Structural,VP(1),VP(2),VP(3),VP(6),VP(7),Viral Structural Proteins VP,Virus Structural Proteins,Proteins, Viral Structural,Proteins, Virus Structural,Structural Polypeptide VP1,Structural Proteins, Viral,Structural Proteins, Virus,VP1, Structural Polypeptide
D016296	Mutagenesis	Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.	Mutageneses