Naked Science Forum

Life Sciences => Cells, Microbes & Viruses => Topic started by: Ellingson, Kenneth L on 13/10/2008 22:11:52

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: Ellingson, Kenneth L on 13/10/2008 22:11:52

Ellingson, Kenneth L  asked the Naked Scientists:

Chris

Why are there only antibiotics for bacteria and none for viruses?

Knute Ellingson, Chicago

What do you think?

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: backgroundwhitenoise on 13/10/2008 23:27:22

Well the very word antibiotic suggests its corallation to bacteria, its anti bacterial it works against bacteria, just like you might find in yogurts probiotics, it means it supports bacterial culture. Antibiotics are just like poisons for bacteria, i know viruses are fought by antibodies in the white blood cells. We give vaccines to people to defend against viruses, the vaccines are just dead or weakened forms of the virus, this gets the body to make antibodies against the injected vaccine and therefore the virus its meant to protect against.

-backgroundwhitenoise

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: RD on 14/10/2008 14:14:55

There are anti-viral drugs. Anti-virals and anti-biotoics could both be described as antimicrobial (http://en.wikipedia.org/wiki/Antimicrobial).

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: Pseudogene on 14/10/2008 20:08:58

Specifically it is the mode of action that makes antibiotics bacterial specific.  They interrupt the development of the bacterial cell wall resulting in the lysis (death) of the bacterial cells.  In antibiotic resistant bacteria they have a slightly different enzyme that allows them to catalyse the antibiotic molecules thus negating their mode of action.

Anti-virals (IIRC) work by specifically stimulating an arm of the immune system that involves T-cells and antigen presenting cells.  It's like a little booster for your immune system

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: RD on 15/10/2008 00:53:37

Quote from: Pseudogene on 14/10/2008 20:08:58

Anti-virals (IIRC) work by specifically stimulating an arm of the immune system that involves T-cells and antigen presenting cells.  It's like a little booster for your immune system

There are several types of anti-viral treatments, some of which do not involve stimulating the immune system,
e.g. preventing the virus entering cells by blocking receptors on the cell surface, or by interfering with virus replication.

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: Pseudogene on 15/10/2008 06:37:38

thanks for the clarification.

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: Bored chemist on 15/10/2008 20:08:20

Not all antibiotics work by preventing the growth of bacterial cell walls. Pebicilin and some related ones do but not all of them.
For example
Nonactin has been reported to specifically inhibit the processing of cytoplasmic precursor proteins destined for the mitochondria. It is able to uncouple the oxidative phosphorylation of mitochondria of rat liver in a low concentration, and can also carry cations across biological and artificial membranes
(ripped from Wiki)

Title: Why are there only antibiotics for bacteria and none for viruses?
Post by: Pseudogene on 16/10/2008 06:39:43

sorry, I meant penicillin based antibiotics.  I'm awful at this question answering.