Anthracimycin: Difference between revisions

From MicrobeWiki, the student-edited microbiology resource
No edit summary
No edit summary
Line 13: Line 13:
Anthracimycin, according to Professor Fenical, has a "new and unique chemical structure" (Aguilera). New antibiotics do not often have completely unique structures, which is what makes the discovery of anthracimycin particularly important. The chemical formula of anthracimycin is C25H32O4. It is composed of three rings: one has fourteen carbon atoms, and two have six carbon atoms each (Jang et. al). These rings are of a polyketide origin, which simply means that they contain ketone groups.  Ketones contain carbonyl groups connected to a carbon atom in the middle of a carbon chain. ("Organic Chemistry" 3).  
Anthracimycin, according to Professor Fenical, has a "new and unique chemical structure" (Aguilera). New antibiotics do not often have completely unique structures, which is what makes the discovery of anthracimycin particularly important. The chemical formula of anthracimycin is C25H32O4. It is composed of three rings: one has fourteen carbon atoms, and two have six carbon atoms each (Jang et. al). These rings are of a polyketide origin, which simply means that they contain ketone groups.  Ketones contain carbonyl groups connected to a carbon atom in the middle of a carbon chain. ("Organic Chemistry" 3).  


Although anthracimycin has a unique structure, it is closely related to a compound called chlorotonil A.  Chlorotonil A is a metabolite derived from a terrestrial bacterium called Sorangium cellulosum ("Anthrax Killer From the Sea"). It differs in structure from anthracimycin in that it contains two chlorine atoms and it has a slightly different carbon skeleton (Jang et. al). The bioactivity of chlorotonil A has not yet been determined, but research suggests that it may have uses similar to anthracimycin (Gerth et al.)
Although anthracimycin has a unique structure, it is closely related to a compound called chlorotonil A.  Chlorotonil A is a metabolite derived from a terrestrial bacterium called Sorangium cellulosum ("Anthrax Killer From the Sea"). It differs in structure from anthracimycin in that it contains two chlorine atoms and it has a slightly different carbon skeleton (Jang et. al). The bioactivity of chlorotonil A has not yet been determined, but the most recent research suggests that it may have uses similar to anthracimycin (Gerth et al.)


The main techniques used to determine the chemical structure of anthracimycin were spectroscopy and x-ray crystallography. Spectroscopy is a process often used to study the structure of molecules. It involves determining the wavelength of different elements of a molecule, and using that information to determine its chemical structure (Kulesa). X-ray crystallography involves beaming x-rays at a crystallized compound and studying the diffraction pattern to determine the chemical structure of the compound. In the Jang, et al. study, spectroscopy provided a more general picture of anthracimycin's structure, while x-ray crystallography gave the specific locations of carbon atoms.  
The main techniques used to determine the chemical structure of anthracimycin were spectroscopy and x-ray crystallography. Spectroscopy is a process often used to study the structure of molecules. It involves determining the wavelength of different elements of a molecule, and using that information to determine its chemical structure (Kulesa). X-ray crystallography involves beaming x-rays at a crystallized compound and studying the diffraction pattern to determine the chemical structure of the compound. In the Jang, et al. study, spectroscopy provided a more general picture of anthracimycin's structure, while x-ray crystallography gave the specific locations of carbon atoms.  
Line 25: Line 25:


==Conclusion==
==Conclusion==
Research on anthracimycin is still in the early stages. The antibiotic shows promising potential against gram-positive bacteria, and possibly gram-negative bacteria as well. The marine origin of anthracimycin suggests that the oceans may be a new location to find medically important materials. The discovery of new antibiotics is key to staying ahead of bacterial evolution so that treatments against infections are always effective.  
Research on anthracimycin is still in the early stages. The antibiotic shows promising potential against gram-positive bacteria, and possibly gram-negative bacteria as well. The marine origin of anthracimycin suggests that the oceans may be a new location to find medically important materials. The discovery of new antibiotics is key to staying ahead of bacterial evolution so that treatments against infections remain effective.  


==References==
==References==

Revision as of 00:30, 4 December 2013

Introduction

Anthracimycin is an antibiotic that is able to kill gram-positive bacteria, namely anthrax (Bacillus Anthracis). In addition, a chlorinated variant has shown activity against certain gram-negative bacteria. It also may be able to kill the gram-positive methicillin-resistant staphylococcus aureus (MRSA), and therefore is an extremely relevant research topic. MRSA is a growing problem in the modern world because of its astonishing capacity to develop drug resistance, so a new antibiotic that defends again MRSA would be a revolutionary discovery. It is a metabolite derived from an ocean microbe called Streptomyces sp. Professor Wiliam Fenical, along with his team of researchers, discovered the compound in 2012 in Santa Barbara, California.

Electron microscopy view of anthracimycin, http://cdn4.sci-news.com/images/2013/07/image_1241_1-anthrax.jpg




Chemical Structure of Anthracimycin

Anthracimycin, according to Professor Fenical, has a "new and unique chemical structure" (Aguilera). New antibiotics do not often have completely unique structures, which is what makes the discovery of anthracimycin particularly important. The chemical formula of anthracimycin is C25H32O4. It is composed of three rings: one has fourteen carbon atoms, and two have six carbon atoms each (Jang et. al). These rings are of a polyketide origin, which simply means that they contain ketone groups. Ketones contain carbonyl groups connected to a carbon atom in the middle of a carbon chain. ("Organic Chemistry" 3).

Although anthracimycin has a unique structure, it is closely related to a compound called chlorotonil A. Chlorotonil A is a metabolite derived from a terrestrial bacterium called Sorangium cellulosum ("Anthrax Killer From the Sea"). It differs in structure from anthracimycin in that it contains two chlorine atoms and it has a slightly different carbon skeleton (Jang et. al). The bioactivity of chlorotonil A has not yet been determined, but the most recent research suggests that it may have uses similar to anthracimycin (Gerth et al.)

The main techniques used to determine the chemical structure of anthracimycin were spectroscopy and x-ray crystallography. Spectroscopy is a process often used to study the structure of molecules. It involves determining the wavelength of different elements of a molecule, and using that information to determine its chemical structure (Kulesa). X-ray crystallography involves beaming x-rays at a crystallized compound and studying the diffraction pattern to determine the chemical structure of the compound. In the Jang, et al. study, spectroscopy provided a more general picture of anthracimycin's structure, while x-ray crystallography gave the specific locations of carbon atoms.

Method of Action and Potential Uses

The method of action of anthracimycin is not yet determined. Scientists initially hypothesized that it inhibited DNA/RNA synthesis, but follow-up studies (Jang et. al) rejected this hypothesis. Anthracimycin has been shown to effectively kill gram positive bacteria. It has been proven effective against the spore-forming bacterium Bacillus anthracis, which causes an infectious disease called anthrax. This bacterium has been used most notably as a bioterrorism weapon. Anthrax is potentially lethal, and can require months of treatment with multiple antibiotics ("Anthrax Killer from the Sea"). Therefore, discoveries of new antibiotics to treat anthrax are medically significant. Anthracimycin also showed antimicrobial activity against staphylococci, enterococci, and streptococci. Based on this action, scientists predict that it may be able to kill MRSA, another gram-positive bacterium.

In the Jang, et. al. study, two chlorine atoms were added to anthracimycin to determine whether the addition of chlorine changes the antibiotic's effectiveness. Adding chlorine atoms altered the structure to make it closer to the structure of chlorotonil. The addition of chlorine atoms reduced anthracimycin's effect on Bacillus anthracis by about half. However, adding chlorine atoms greatly increased its activity against certain gram-negative bacteria. These bacteria, such as E. coli and H. influenzae, often develop drug resistance. Therefore, the chlorinated derivative of anthracimycin may also prove to be medically useful.


Conclusion

Research on anthracimycin is still in the early stages. The antibiotic shows promising potential against gram-positive bacteria, and possibly gram-negative bacteria as well. The marine origin of anthracimycin suggests that the oceans may be a new location to find medically important materials. The discovery of new antibiotics is key to staying ahead of bacterial evolution so that treatments against infections remain effective.

References

Aguilera, Mario. "Compound Discovered at Sea Shows Potency against Anthrax." Scripps Institution of Oceanography. 17 July 2013. Web. 05 Nov. 2013.

"Anthracimycin: New Antibiotic Kills Anthrax, MRSA." Scinews.com. 19 July 2013. Web. 05 Nov. 2013.

"Anthrax Killer from the Sea." Chemistry Views. 01 July 2013. Web. 7 Nov. 2013.

Organic Chemistry: Structure and Function. Ed. P. Vollhardt and N. Schore. 5th ed. New York: W. H. Freeman and, 2007. 3. Print.

Gerth, K., et al. "Chlorotonil A, a Macrolide with a Unique gem-Dichloro-1,3-dione Functionality from Sorangium cellulosum, So ce1525." Angewandte Chemie International Edition 47.3 (2008): 600–602. Wiley Online Library. Web. 3 December 2013.

Jang, Kyoung H, et. al. "Anthracimycin, a Potential Anthrax Antibiotic from a Marine-Derived Actinomycete." Angewandte Chemie International Edition 52.30 (2013): 7822-824. Wiley Online Library. Web. 7 Nov. 2013.

Kulesa, Craig. "What Is Spectroscopy?" What Is Spectroscopy? 4 Feb. 1997. Web. 02 Dec. 2013.


"X-ray Crystallography." X-RAY Crystallography. St. Olaf College. Web. 03 Dec. 2013.



Edited by [Emily Vachon], student of Joan Slonczewski for BIOL 116 Information in Living Systems, 2013, Kenyon College.