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(at most several
hundred genes)
(capsid)
Viruses
Are
Noncellular!
(Nonliving)
Retrovirus
Animal cell infection
Super HIV Strain Rattles Experts
patients to see if either are the source of a more
aggressive and more drug-resistant strain of HIV.
They are concerned about a new strain of HIV
that rapidly progresses from infection to AIDS.
Though the cases have been few and isolated,
at-risk communities are alarmed and frightened
by the recent discoveries and developments.
PrPSc
PrPc
From Dr Jekyll to Mr Hyde
The prion protein exists in two forms.
The normal, innocuous protein (PrPc) can change
its shape to a harmful, disease-causing form (PrPSc).
The conversion from PrPc to PrPSc then proceeds via
a chain-reaction. When enough PrPSc proteins
have been made they form long filamentous aggregates
that gradually damage neuronal tissue. The harmful
PrPSc form is very resistant to high temperatures,
UV-irradiation and strong degradative enzymes.
Figure 9. Increase of bacteria resistant to 3 antibiotics over time
and cartoon of Superbacteria with many resistance plasmids.
Plasmids
Episomes
Chromatin modifications
(imprinting)