Mircobiology: Virus 2, lecture 9

Bacteriophages: Lytic vs lysogenic cycle

Lytic infection causes lysis(rupture of host cell)

Lysogeny, phage genome integrates in host cell allowing it to replicate the prophage(integrated phage genome) as the cell divides, humans can go through both

Antigenic drift

lack of proofreading leads to accumulation of random mutations to viruses with mutant proteins are no longer recognized by host

Antigenic shift

segments from different strains reassort by coinfection of a host cell

Virus can lead to HPV(cancer)

A DNA virus may cause cancer by disrupting host cell growth regulation

Virus are difficult to treat with antivirals

combination therapy treating different steps, consistent adherence is essential to prevent resistance, prevention and vaccination is much more effective

Viruses can be beneficial

leftover viral protein repurposed, viruses can be engineered as tools to deliver genes or other genetic material into cell, bacteriophages can potentially be used to treat bacterial infections

Fungal cell wall

Contain chitin

Chitin and Ergosterol

Anti-fungal targets

yeast

single-celled fungi, reproduction

Filamentous fungi(multicellular)

Fungi(hyphae) extend and form branches, form mycelium(mold) network

Fungal spores

different than endospores, reproductive structure produced by many fungi that can spread through air, water, and contact, highly resistant to environment condtions, can cause allergic reactions

Mycotoxins

Toxic chemicals produced by certain fungi, expose can cause anything from acute to long term organ damage, depending on toxin and dose, they can remain in food even after fungus itself is no longer visible

Fungus can be beneficial too

-break down organic matter

-essential for fermented food, beer, bread, cheese

-important drugs like penicillin

-produce enzymes, pharmaceuticals, and other useful products