Biomaterial Database

Fibrous projections from the core of a bacteriophage T7 procapsid. 1979

P Serwer

A cylindrical core previously demonstrated in a bacteriophage T7 procapsid (capsid I) has been further examined by electron microscopy. Fibrous extensions of the core have been observed; these fibers appear to connect the core to the capsid I envelope. After infection of a nonpermissive host with bacteriophage T7 amber mutant in any gene coding for a core protein, the resulting lysates contained more noncapsid assemblies of capsid envelope protein than did wild-type lysates; these assemblies had a mass two to at least 500 times greater than the mass of capsid I. This suggests that the internal core and fibers assist the assembly of subunits in the envelope of capsid I.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D005814	Genes, Viral	The functional hereditary units of VIRUSES.	Viral Genes,Gene, Viral,Viral Gene
D013604	T-Phages	A series of 7 virulent phages which infect E. coli. The T-even phages T2, T4; (BACTERIOPHAGE T4), and T6, and the phage T5 are called "autonomously virulent" because they cause cessation of all bacterial metabolism on infection. Phages T1, T3; (BACTERIOPHAGE T3), and T7; (BACTERIOPHAGE T7) are called "dependent virulent" because they depend on continued bacterial metabolism during the lytic cycle. The T-even phages contain 5-hydroxymethylcytosine in place of ordinary cytosine in their DNA.	Bacteriophages T,Coliphages T,Phages T,T Phages,T-Phage
D014764	Viral Proteins	Proteins found in any species of virus.	Gene Products, Viral,Viral Gene Products,Viral Gene Proteins,Viral Protein,Protein, Viral,Proteins, Viral