HIV MATURATION

The HIV virion undergoes a dramatic change during maturation. The Gag polyproteins are cleaved by PR protease to give rise to the viral matrix, capsid and nucleocapsid. Only then is the virion termed mature and can go on to infect other susceptible cells. This step is thus a potential drug target.

10.1101/cshperspect.a006924
10.1016/0042-6822(87)90449-1
viralzone.expasy.org/7
Wikipedia HIV Virion

THE GENOME OF ΦX174

ΦX174's tiny circular genome harbors many surprises amongst its 11 ORFs. There is a section coding for three proteins at once in all 3 available reading frames! When scientists originally acquired this sequence in 1977, some joked the phage seems to have been designed by an advanced alien civilisation.

NC_001422
viralzone.expasy.org/114

PODOPHAGE ASSEMBLY

Many viruses, Podophages such as T7 and T3 included, assemble their virions in an intricate way. First, the procapsid is prepared, which is only later filled with the viral double-stranded DNA. The terminase performs this feat, cutting up the nascent genome concatemer into appropriate lengths.

viralzone.expasy.org/1950
viralzone.expasy.org/3944