The carriage of the serine-aspartate repeat protein-encoding sdr genes among Staphylococcus aureus lineages

Abstract

The serine-aspartate repeat proteins (Sdr) are members of a family of surface proteins and contribute to the pathogenicity of Staphylococcus aureus. Among 288 S. aureus isolates including 158 and 130 associated with skin and soft tissue infections and bloodstream infection, respectively; 275 (95.5%) were positive for at least one of three sdr genes tested. The positivity rates for sdrC, sdrD, and sdrE among S. aureus isolates were 87.8% (253/288), 63.9% (184/288), and 68.1% (196/288), respectively. 224 (77.8%) of 288 isolates were concomitantly positive for two or three sdr genes. There was an association between carriage of sdrE and methicillin-resistant S. aureus (MRSA) isolates, while the carriage rates of sdrC and sdrD in MRSA isolates were similar to those in methicillin-sensitive S. aureus (MSSA) isolates. The prevalence of co-existence of sdrC and sdrE among MRSA isolates was significantly higher than that among MSSA isolates (p<0.05). All ST1, ST5, ST7, and ST25 isolates were positive for sdrD. While all ST121 and ST398 isolates were negative for sdrD. All ST59 and ST88 isolates were positive for sdrE. All ST1 isolates were concomitantly positive for sdrC and sdrD. Concomitant carriage of sdrC, sdrD, and sdrE was found among all ST5, 75.0% (9/12) of ST1, 69.2% (9/13) of ST6, 78.6% (11/14) of ST25, and 90.9% (20/22) of ST88 isolates. sdrD was linked to CC5, CC7 and CC88 isolates, especially CC88 isolates. There was a strong association between the presence of sdrE and CC59, CC88, and CC5 isolates. A significant correlation between concomitant carriage of sdrC, sdrD, and sdrE and CC88 isolates was found. sdrC-positive, sdrD-positive and sdrE-negative gene profile was significantly associated with CC7 clone. There was an association between sdrC-positive, sdrD-negative, and sdrE-positive gene profile and CC59 isolates. A correlation between sdrC-positive, sdrD-negative, and sdrE-negative gene profile and CC121 clone was found. More CC59 isolates carried sdrC-negative, sdrD-negative, and sdrE-positive gene profile relative to other four CCs isolates. All ST1 and ST5, 95.2% (20/21) of ST188 and 95.2% (20/21) of ST630 isolates were positive for sdrC. Taken together, our investigation indicated that different S. aureus lineages were associated with specific patterns of carriage of sdr genes.

Molecular analysis, biofilm formation, and susceptibility of methicillin-resistant Staphylococcus aureus strains causing community- and health care-associated infections in central venous catheters

“…These results contradicted our findings because these studies used different specimens to isolate the pathogens 58,60 . The results of the prevalence of adhesion genes among MRSA agrees with those of previous studies 61,62 . The presence of adhesion genes in most MRSA isolated from CVC-related infection was complementary to biofilm formation and posed resistance to antibiotics.…”

Phenotypic and molecular characteristics ofStaphylococcus aureusand methicillin-resistantStaphylococcus aureusin slaughterhouse pig-related workers and control workers in Guangdong Province, China

“…We found that the overlap of livestock-associated characteristics was only observed in MRSA CC9 from pig-related workers, indicating a potential risk for livestock-to-human LA-MRSA transmission by occupational pig exposure. Note that CC7, CC59, CC6, and CC188 were the predominant CC types among S. aureus isolates from hospitalized patients [32, 33] and healthy workers in this study, indicating that these CC types probably belonged to human association. We found there was no significant difference in IEC profile or antimicrobial resistance for human-associated CCs between the groups, revealing the potential human-to-human transmission of human-associated MRSA.…”

“…hardware factory or biscuit factory) in each city were sampled to enroll about 200 control workers with no occupational livestock exposure. After obtaining informed consent, two nasal swabs were taken from each participant and a face-to-face questionnaire was administered to collect influencing factors of S. aureus carriage, including sex, age (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), and 41-60 years), education (elementary school, junior high school, senior high school, and above), personal monthly income (4¥1000, ¥1001-2000, ¥2001-3000, or 5¥3001), occupational pig exposure (yes or no), antimicrobial use in the last month (yes or no), and visit to medical facilities in the last month (yes or no).…”

Effect of genetic background on the evolution of Vancomycin-Intermediate Staphylococcus aureus (VISA)

“…The sdr locus encodes sdrC, sdrD, sdrE which are members of the repeat-rich microbial surface components recognizing adhesive matrix molecules (MSCRAMM) family (Josefsson et al, 1998). These genes are not always conserved together (Liu et al, 2015), and their presence has been associated with bone infection (Sabat et al, 2006), resistance to host immunity (Sitkiewicz, Babiak & Hryniewicz, 2011;Askarian et al, 2017), biofilm formation (Barbu et al, 2014), and host-cell adhesion (Corrigan, Miajlovic & Foster, 2009;Cheng et al, 2009;Barbu et al, 2010;Askarian et al, 2016). Belikova et al (2020) showed that in USA300 sdr genes undergo frequent within-genome recombination during growth in lab conditions and during infection.…”