Distribution of SCCmec-associated phenol-soluble modulin in staphylococci

Abstract

Please cite this article as: Monecke S, Engelmann I, Archambault M, Coleman DC, Coombs GW, Cortez de Jäckel S, Pelletier-Jacques G, Schwarz S, Shore AC, Slickers P, Ehricht R, Distribution of SCCmecassociated phenol-soluble modulin in staphylococci, Molecular and Cellular Probes (2012), doi: 10.1016/ j.mcp.2012 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AB547236.1) and S. vitulinus (AB546780.1).The aim of this study was to screen staphylococcal isolates for the presence of PSM-mec in order to obtain more data on its distribution. 102 S. aureus isolates and 38 coagulase-negative staphylococci were genotyped using DNA microarrays (StaphyType, Alere Technologies GmbH, Jena, Germany, [7,9]). This allowed characterising their SCCmec elements [10]. In addition, SCCmec elements of some isolates have previously been studied comprehensively [11,12]. PCR primers pr_psmMEC_02 (5'-CGAAAGCCTGAATGCAAGTCT-3') and pr_psmMEC_03(5'-GGATTTCACTGGTGTTATTACAAGC-3') were used to detect PSM-mec. Reaction conditions included an initial denaturation (2 min at 96°C) followed by 35 cycles (20 sec at 96°C, 20 sec at 70°C and 20 sec at 72°C). A second PCR covered a region spanning from xylR to PSMmec (pr_psmMEC_02 and pr_xylR_04, 5'-AAGCGTCATCTTCTCATTTAGTTGA-3') and a third PCR covered the region from PSM-mec to mecR1 (pr_mecR_01, 5'-CCAGAAAGTAAACAACGATATTCACC-3' and pr_psmMEC_03). Both reactions comprised denaturation (2 min at 96°C) followed by 35 cycles (20 sec at 96°C, 20 sec at 55°C and 70 sec at The results are summarised in Table 1 vitulinus. The presence of PSM-mec did not depend on the host species, and was found in isolates from humans, dogs, cats, goats, cattle, pigs and turkeys. PSM-mec was absent in SCCmec types I, IIC, IIE, IV, V or XI and in SCC elements lacking the mec complex. Some isolates, including CC12-MRSA, WA-MRSA-59, harboured SCCmec elements comprising mecR1 but lacking xylR.These strains were PSM-mec-negative.There was no evidence for alternative locations of PSM-mec. Isolates lacking SCCmec elements, or harbouring SCCmec types I, IIC, IIE, IV and V were PSM-mec-negative regardless of clonal complex or species affiliation. A PCR covering the region from xylR to PSM-mec using primers pr_psmMEC_02/pr_xylR_04 yielded results which were in all cases but one in accordance with the PSM-mec PCR. In a PSM-mec-positive CC5-MRSA, xylR was absent, and primer pair pr_psmMEC_02/pr_xylR_04 did not yield a result.Results of a third PCR (pr_psmMEC/pr_mecR_01) differed from those of the other two PCRs by yielding negative results for ST8-MRSA-IIA or -IID, and for deletion variants of this strain. This can be attrib...

Inhibition of Exotoxin Production by Mobile Genetic Element SCCmec-Encoded psm-mec RNA Is Conserved in Staphylococcal Species

“…This is the first report to reveal that the regulatory role of a mobile genetic element-encoded factor on host bacterial virulence is conserved among the species incorporating the mobile genetic element. Because the SCC mec carrying psm-mec is widely observed among staphylococcal species, including S. aureus, S. epidermidis, S. haemolyticus, S. hominis, S. pseudintermedius, S. saprophyticus, S. fleurettii, S. vitulinus, and S. simulans [14], [17], the inhibitory effect of psm-mec against exotoxin production is assumed to confer conserved advantages to staphylococcal bacteria in their survival in host animals and may cause a positive effect on the dissemination and maintenance of SCC mec .…”

“…The function of psm-mec to inhibit exotoxin production and to increase biofilm formation might contribute to alleviate excess damage to host animals and to survive in the host environment. The psm-mec exists not only in S. aureus , but also in other staphylococcal species [17]. It has remained unclear, however, whether the regulatory function of psm-mec is conserved among the staphylococcus species carrying SCC mec, which needs the conserved interaction between the mobile genetic element-encoded psm-mec and core genome encoded-virulence factors.…”

PSM-Mec—A Virulence Determinant that Connects Transcriptional Regulation, Virulence, and Antibiotic Resistance in Staphylococci

“…The psm-mec locus is found in the J2 region adjacent to mecI of the class A mec gene complex in several widespread HA-MRSA lineages, but most prominently in Sequence Type (ST) 5, ST36, ST45, ST225, and ST239 strains (Deurenberg and Stobberingh, 2009; Nübel et al, 2010; Castillo-Ramirez et al, 2012; Schulte et al, 2013), which all have either SCC mec types II or III (Chatterjee et al, 2011; Monecke et al, 2012; Josten et al, 2014). However, more detailed analysis revealed that the psm-mec locus is found in SCC mec types II, IIA, IIB, IID, III, and VIII of many Staphylococcus species (Monecke et al, 2012; Shore and Coleman, 2013).…”

“…However, more detailed analysis revealed that the psm-mec locus is found in SCC mec types II, IIA, IIB, IID, III, and VIII of many Staphylococcus species (Monecke et al, 2012; Shore and Coleman, 2013). …”

Modulation of ccrAB Expression and SCC mec Excision by an Inverted Repeat Element and SarS in Methicillin-Resistant Staphylococcus aureus

“…Acquisition of SCCmec not only gives S. aureus the ability to become resistant to almost the entire class of ␤-lactam antibiotics but also modulates the virulence (35) and agr quorum sensing (36) in some strains. SCCmec types II, III, and VIII and some irregular or truncated SCCmec elements harbor the toxin gene psm-mec (37), which codes for a regulatory RNA and modulates the virulence of MRSA through suppressing AgrA translation (38). As displayed before, SCCmec can be excised from or integrated into bacterial chromosomes mediated by CcrAB recombinases, which are encoded by ccrAB genes (5).…”