Global acquisition of genetic material from different bacteria into the staphylococcal cassette chromosome elements of a Staphylococcus epidermidis isolate.
Staphylococcus epidermidis has been suggested as a main reservoir of methicillin resistance and virulence genes facilitating the evolution of Staphylococcus aureus as a successful pathogen. However, it remains a mystery where and how S. epidermidis obtains these numerous genes to serve as the reservoir. In this study, methicillin-resistant S. epidermidis isolate NW32 from a mastitic milk sample was sequenced and its staphylococcal cassette chromosome (SCC) elements were characterised. The SCC composite island covered 3.5% of the genome and consisted of three intact SCC elements carrying resistance genes against β-lactam antibiotics, several heavy metals and polyamines as well as genes for utilisation of sorbitol as a carbon source. Analysis of the postulated evolutionary route suggested that the three SCC elements were assembled from genetic material from various bacterial species (staphylococci, streptococci, salinicocci and Lysinibacillus) from three habitats (human, soil and cow) in different countries (Asia, North America, South America and Europe). We propose that the hsdS restriction-modification profile and the lack of CRISPR (clustered regularly interspaced short palindromic repeat) sequences in this bacterium may facilitate the genetic exchange of SCC elements among different staphylococcal species.
['Xue|Huping|H|', 'Wu|Zhaowei|Z|', 'Qiao|Dandan|D|', 'Tong|Chao|C|', 'Zhao|Xin|X|']
D000818:Animals D001426:Bacterial Proteins D002417:Cattle D064112:Clustered Regularly Interspaced Short Palindromic Repeats D015280:DNA Restriction-Modification Enzymes D004269:DNA, Bacterial D022761:Gene Transfer, Horizontal D016680:Genome, Bacterial D006801:Humans D019216:Metals, Heavy D016106:Methicillin Resistance D055624:Methicillin-Resistant Staphylococcus aureus D008826:Microbial Sensitivity Tests D008892:Milk D011073:Polyamines D013012:Sorbitol D013212:Staphylococcus epidermidis D013291:Streptococcus D014774:Virulence D047090:beta-Lactams
Staphylococcal cassette chromosome element Assembly Genetic material exchange Methicillin-resistant Staphylococcus aureus Restriction-modification system USA300