1887

Chapter 15 : Antibiotics That Affect Membrane Permeability

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Ebook: Choose a downloadable PDF or ePub file. Chapter is a downloadable PDF file. File must be downloaded within 48 hours of purchase

Buy this Chapter
Digital (?) $30.00

Preview this chapter:
Zoom in
Zoomout

Antibiotics That Affect Membrane Permeability, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555817794/9781555812584_Chap15-1.gif /docserver/preview/fulltext/10.1128/9781555817794/9781555812584_Chap15-2.gif

Abstract:

The polymyxins are a group of cyclic, polycationic peptide antibiotics with a fatty acid chain attached to the peptide through an amide linkage. They are produced by fermentation of strains of Bacillus polymyxa. Polymyxins B and E (colistin) are the least toxic and are the only polymyxins used clinically. These antibiotics contain a 7-amino-acid ring attached to a 3-amino-acid tail, to which is attached a fatty acyl group. It has been suggested that the fatty acid part of the polymyxin molecule penetrates into the hydrophobic region of the outer membrane and the ammonium groups interact with the lipopolysaccharides and phospholipids, competitively displacing divalent cations (calcium and magnesium) from the negatively charged phospholipid group of the membrane lipids. This displacement disrupts membrane organization and increases the permeability of the membrane. Polymyxins B and E are active almost exclusively against aerobic gram negative bacilli. In particular, they exhibit quite good activity against Pseudomonas aeruginosa. In the past, these polymyxins were often used for the treatment of P. aeruginosa infections. Nowadays, because of the availability of effective and less toxic drugs such as gentamicin, tobramycin, amikacin, ticarcillin, piperacillin, and ceftazidime, polymyxins are not the antibiotics of choice to treat infections caused by this bacterium.

Citation: Mascaretti O. 2003. Antibiotics That Affect Membrane Permeability, p 217-218. In Bacteria versus Antibacterial Agents. ASM Press, Washington, DC. doi: 10.1128/9781555817794.ch15
Highlighted Text: Show | Hide
Loading full text...

Full text loading...

Figures

Image of Figure 15.1
Figure 15.1

Chemical structure of polymyxin B1 sulfate.

Citation: Mascaretti O. 2003. Antibiotics That Affect Membrane Permeability, p 217-218. In Bacteria versus Antibacterial Agents. ASM Press, Washington, DC. doi: 10.1128/9781555817794.ch15
Permissions and Reprints Request Permissions
Download as Powerpoint

References

/content/book/10.1128/9781555817794.chap15
1. Kucers, A.,, S. M. Crowe,, M. L. Grayson,, and J. F. Hoy. 1997. The Use of Antibiotics, 5th ed., p. 667675. Butterworth- Heinemann, Oxford, United Kingdom.
2. Wilkinson, S. 1963. Identity of colistin and polymyxin E. Lancet i:922.

Tables

Generic image for table
Table 15.1

Generic and common trade names of polymyxins, the preparations available, and manufacturers in the United States

Citation: Mascaretti O. 2003. Antibiotics That Affect Membrane Permeability, p 217-218. In Bacteria versus Antibacterial Agents. ASM Press, Washington, DC. doi: 10.1128/9781555817794.ch15

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error