Running head: ANTIBIOTICS AND ANTIMICROBIALS

Antibiotics and Antimicrobials

June Saxton

Kaplan University

HS320

Susan Galindo

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ANTIBIOTICS AND ANTIMICROBIALS

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

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ANTIBIOTICS AND ANTIMICROBIALS

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.

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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

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