Running head: ANTIBIOTICS AND ANTIMICROBIALS
Antibiotics and Antimicrobials
June Saxton
Kaplan University
HS320
Susan Galindo
1
ANTIBIOTICS AND ANTIMICROBIALS
2
Antibiotics and Antimicrobials
The early efforts of microbiologists were primarily directed toward enhancing the
body’s natural defenses by the use of vaccines, but in the 1940’s the advent of antimicrobial
drugs doctors found that they could greatly change the course of infectious disease
(Pommerville, 2011). Antibiotics are derived from microorganisms and they can inhibit or
destroy the growth of other microorganisms whereas antimicrobials include any substance which
is able to destroy of inhibit the growth of microorganisms (Todar, 2009).
Evolutionary change in antibiotic and antimicrobial usage
The era of the use of chemicals to treat infections, disease and cancer began with Paul
Ehrlich in the early 1900’s when he thought he could discover specific chemicals that would
seek out and destroy specific disease organisms and destroy them without harming the body. He
and his researchers discovered the first chemical that fought disease. This drug was developed to
fight T. pallidum and contained arsenic. In 1910, they gave it to doctors (brand name Salvarsan)
to use against syphilis. His team approach toward drug discovery became the model which we
still use today in pharmaceutical research (Pommerville, 2011).
The discovery of chemical agents pre-dated the discovery of penicillin in 1929, by Paul
Fleming. Penicillin was the first antibiotic but it wasn’t mass produced until 1945 (Aminov,
2010). Fleming was not the first to note the antibacterial qualities of the Penicillium species.
Joseph Lister observed it in 1871, John Tyndall did in 1876 and Ernest Duchesne wrote a
research paper in 1896. Fleming was the first, however, to propose that in could be used to
eliminate gram-positive bacteria from mixed cultures (Pommerville, 2011).
In 1932, Gerhard Domagk discovered that Prontosil was effective against staphylococci,
streptococci and other gram-positive bacteria for which he was awarded the Nobel Prize in 1939
ANTIBIOTICS AND ANTIMICROBIALS
3
in Physiology or Medicine (Pommerville, 2011).
These three antimicrobials, Salvarsan, Penicillin and Prontosil were responsible for the
paradigms for further drug research and resulted in the discovery of new antibiotics and
antimicrobials (Aminov, 2010).
Preventing disease with antibiotics and antimicrobials
Antibiotics and antimicrobials prevent infection in several ways i.e. by targeting specific
metabolic reactions, inhibiting cell wall synthesis, affecting the cell wall membrane, affecting
protein synthesis and inhibiting nucleic acid synthesis. Sulfonamides target specific metabolic
reactions. The cell wall synthesis inhibitors include natural and synthetic penicillin’s and
cephalosporins, vancomycin, bacitracin, isoniazid and ethambutol. Polymyxin is a cell
membrane inhibitor. Inhibitors of protein synthesis make up a wide variety of antibiotic and
antimicrobials. These include tetracyclines, macrolides, streptogramins and oxazolidnodes just to
name a few. The inhibitors of DNA and RNA synthesis include ciprofloxacin and Rifampin
(Pommerville, 2011).
Importance of correctly treating microbial infections
Because bacterial species have developed resistance to antibiotic/antimicrobial agents by
altering metabolic pathways ways, inactivating them, reducing cell permeability or modifying
the cell target it is important to correctly identify the correct pathogen and use the correct drug to
treat it. Appropriate diagnosis and antibiotic treatment will limit the chances of the development
of resistant strains and appropriate use of antimicrobials will limit potential antibiotic resistance
(Pommerville, 2011).
Understanding how antibiotics and antimicrobials were developed and how they work
will help us to develop new drugs to fight infection and prevent resistance.
ANTIBIOTICS AND ANTIMICROBIALS
References
Aminov, R. I. (2010, December 8). A brief history of the antibiotic era: Lessons learned and
challenges for the future. Retrieved from
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109405/
Pommerville, J. (2011). Alcamo's fundamentals of microbiology. (9 ed., Vol. 9). Chapter 11
Sudbury: Jones & Bartlett Publishers.
Todar, K. (2009). Antimicrobial agents used in the treatment of infectious disease. Retrieved
from http://textbookofbacteriology.net/themicrobialworld/antimicrobial.html
4