Arginine catabolic mobile element
The arginine catabolic mobile element (ACME) is a mobile genetic element of Staphylococcus bacterial species. This genetic element provides for several immune modulating functions, including resistance to polyamines which serve as a non-specific immune response both on intact skin and following the inflammatory response in wound healing.{{cite journal|last=Otto|first=Michael|title=Community-associated MRSA: What makes them special?|journal=International Journal of Medical Microbiology|date=August 2013|volume=303|issue=6–7|pages=324–330|doi=10.1016/j.ijmm.2013.02.007 |pmid=23517691 |pmc=3729626}}{{cite journal|last=Joshi|first=Gauri S.|author2=Spontak, Jeffrey S.|author3= Klapper, David G.|author4= Richardson, Anthony R.|title=Arginine catabolic mobile element encoded speG abrogates the unique hypersensitivity of Staphylococcus aureus to exogenous polyamines|journal=Molecular Microbiology|date=October 2011|volume=82|issue=1|pages=9–20|doi=10.1111/j.1365-2958.2011.07809.x |pmid=21902734 |pmc=3183340}} Diverse ACME are present in several species of Staphylococcus, including Staphylococcus epidermidis.{{cite journal |author1=Barbier, F. |author2=Lebeaux, D. |author3=Hernandez, D. |author4=Delannoy, A.-S. |author5=Caro, V. |author6=Francois, P. |author7=Schrenzel, J. |author8=Ruppe, E. |author9=Gaillard, K. |author10=Wolff, M. |author11=Brisse, S. |author12=Andremont, A. |author13=Ruimy, R. |title=High prevalence of the arginine catabolic mobile element in carriage isolates of methicillin-resistant Staphylococcus epidermidis|journal=Journal of Antimicrobial Chemotherapy|date=9 November 2010|volume=66|issue=1|pages=29–36|doi=10.1093/jac/dkq410 |pmid=21062794 |doi-access=free }}{{cite journal |author1=Miragaia, Maria |author2=de Lencastre, Herminia |author3=Perdreau-Remington, Francoise |author4=Chambers, Henry F. |author5=Higashi, Julie |author6=Sullam, Paul M. |author7=Lin, Jessica |author8=Wong, Kester I. |author9=King, Katherine A. |author10=Otto, Michael |author11=Sensabaugh, George F. |author12=Diep, Binh An |author13=DeLeo, Frank R. |title=Genetic Diversity of Arginine Catabolic Mobile Element in Staphylococcus epidermidis|journal=PLOS ONE|date=6 November 2009|volume=4|issue=11|pages=e7722|doi=10.1371/journal.pone.0007722 |pmid=19893740 |pmc=2768820 |bibcode=2009PLoSO...4.7722M |doi-access=free }}
Association with virulent [[MRSA]]
ACME are not common among antibiotic sensitive S. aureus (MSSA).{{cite journal|last=Goering|first=R. V.|author2=McDougal, L. K.|author3= Fosheim, G. E.|author4= Bonnstetter, K. K.|author5= Wolter, D. J.|author6= Tenover, F. C.|title=Epidemiologic Distribution of the Arginine Catabolic Mobile Element among Selected Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus Isolates|journal=Journal of Clinical Microbiology|date=4 April 2007|volume=45|issue=6|pages=1981–1984|doi=10.1128/JCM.00273-07 |pmid=17409207 |pmc=1933090 }} The elements for the most prominent MRSA ACME appear to have assembled recently in S. epidermidis into the speG-positive ACME which was transferred to virulent S. aureus during the evolution of the epidemic USA300 MRSA strain.{{cite journal |author1=Planet, P. J. |author2=LaRussa, S. J. |author3=Dana, A. |author4=Smith, H. |author5=Xu, A. |author6=Ryan, C. |author7=Uhlemann, A.-C. |author8=Boundy, S. |author9=Goldberg, J. |author10=Narechania, A. |author11=Kulkarni, R. |author12=Ratner, A. J. |author13=Geoghegan, J. A. |author14=Kolokotronis, S.-O. |author15=Prince, A. |title=Emergence of the Epidemic Methicillin-Resistant Staphylococcus aureus Strain USA300 Coincides with Horizontal Transfer of the Arginine Catabolic Mobile Element and speG-mediated Adaptations for Survival on Skin|journal=mBio|date=17 December 2013|volume=4|issue=6|pages=e00889-13–e00889-13|doi=10.1128/mBio.00889-13 |pmid=24345744 |pmc=3870260 }}{{cite journal |author1=Diep, Binh An |author2=Stone, Gregory G. |author3=Basuino, Li |author4=Graber, Christopher J. |author5=Miller, Alita |author6=Etages, Shelley-Ann des |author7=Jones, Alison |author8=Palazzolo-Ballance, Amy M. |author9=Perdreau-Remington, Françoise |author10=Sensabaugh, George F. |author11=DeLeo, Frank R. |author12=Chambers, Henry F. |title=The Arginine Catabolic Mobile Element and Staphylococcal Chromosomal Cassette Linkage: Convergence of Virulence and Resistance in the USA300 Clone of Methicillin-Resistant|journal=The Journal of Infectious Diseases|date=June 2008|volume=197|issue=11|pages=1523–1530|doi=10.1086/587907 |pmid=18700257 |doi-access=free }} This broadened the ability of S. aureus to colonize sites beyond the nose.{{cite journal|last=Yan|first=Miling|author2=Pamp, Sünje J.|author3=Fukuyama, Julia|author4=Hwang, Peter H.|author5=Cho, Do-Yeon|author6=Holmes, Susan|author7= Relman, David A.|title=Nasal Microenvironments and Interspecific Interactions Influence Nasal Microbiota Complexity and S. aureus Carriage|journal=Cell Host & Microbe|date=December 2013|volume=14|issue=6|pages=631–640|doi=10.1016/j.chom.2013.11.005 |pmid=24331461 |pmc=3902146 }} This strain is able to persist on intact skin and is spread rapidly person-to-person. As a result, the speG-positive ACME is a particularly important element of MRSA pathogenesis.