Bacteriophages filamentous phage

Infection of E coli with filamentous phage is a chronic one in that the phage does not lyse the E. coli. It is therefore possible to maintain filamentous phage either as a phage-secreting E coli strain or as a suspension of bacteriophage particles... 

Lambda phage is closely related to other bacteriophages, and these are called T3, T7, T5, Mu, T2, and T4. All of these phages corcsist of a double-stranded DNA genome, an icosahedral head, a long cylindrical tail, and a variable number of tail filaments. The related filamentous phages are Ml3, fl, and fd. 

Bacteriophages, like all viruses, contain only a single nucleic acid molecule (usually DNA but occasionally RNA) which carries a relatively small number of genes enclosed by a protective protein coat called the capsid. The two main types of phage which infect E. coli are the head-with-tail phages, e.g. phage A., or filamentous phages, e.g. 

FIGURE 19.3 Two types of bacteriophage infecting E. coli. (a) Head-with-tail phages, (b) Filamentous phages... 

Of the many varieties of bacteriophage, only phage X and filamentous M13 have been confirmed as major cloning vectors in E. coli. Phage X has a 48.5 kb DNA molecule which has been sequenced and mapped so that the positions and functions of its genes are known. Related genes, e.g. those... 

Rakonjac, J., Beimett, N.J., Spagnuolo, J., Gagic, D., Russel, M., 2011. Filamentous bacteriophage biology, phage display and nanotechnology applications. Curr. Issues Mol. Biol. 13, 51-76. 

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