Protocol Online logo
Top : New Forum Archives (2009-): : Microbiology

Positive bacteria - does anyone know? (Jun/15/2011 )

Hello everyone!

I'm looking for bacterial strains with positive surface charge in neutral or close to neutral pH. According to the litterature, there are some bacteria that has a positive charge. But I can't seem to find any examples.

Does anyone know about this?

-k_josefin-

k_josefin on Thu Jun 16 05:46:08 2011 said:


Hello everyone!

I'm looking for bacterial strains with positive surface charge in neutral or close to neutral pH. According to the litterature, there are some bacteria that has a positive charge. But I can't seem to find any examples.

Does anyone know about this?


Think about using Staphylococcus aureus. One of the major lipids in staph is lysyl-phosphatidylglycerol. This polar lipid has a positively charged lysine attached. The membrane is subsequently positively charged in an attempt to repel cationic antiomicrobial peptides.

-Bluefunk-

Its a bit more complicated then Bluefunk said, but in essence, its ok.

In general: the charge is negative.. for gram - and gram +
This characteristic is used for example to concentrate toxic waste and more specific radioactive waste.

However, under certain circumstances, the charge can be altered by the bacterium in a response on the pH. Its a defence mechanism of the bacterium to survive.

I do not know if you had basic microbial physiology? Of not, try to look it up..


I also included a paper to start .. it gives you an example, Bluefunk allready mentioned S. A.

Its not so hard to find other examples if you search a bit.
Attached File

Attached File

-pito-