title: Identification and Characterization ofStaphylococcus aureusStrains with an Incomplete Hemolytic Phenotype.
abstract: Staphylococcus aureusis a common pathogen causing both hospital and community-acquired infections. Hemolysin is one of the important virulence factors forS. aureusand causes the typical β-hemolytic phenotype which is called complete hemolytic phenotype as well. Recently,S. aureuswith an incomplete hemolytic phenotype (SIHP) was isolated from clinical samples. To study the microbiologic characteristics of SIHP, the special hemolytic phenotype of SIHP was verified on the sheep blood agar plates supplied by different manufacturers. Expression of hemolysin geneshla, hlb, hlgC, andhldof SIHP was detected by qRT-PCR and it was showed that expression ofhlbin SIHP was obviously increased compared to the controlS. aureusstrains with complete hemolytic phenotype (SCHP), while the expression ofhla, hlgC, andhldin SIHP was significantly decreased. In addition, the α-hemolysin encoded by genehlawas decreased obviously in SIHP compared to SCHP by western blot. All 60 SIHP strains were identified to be the methicillin resistantS. aureus(MRSA), and moreover these SIHP strains all containsmecAgene. The virulence genetstwere all present in SIHP, and the intracellular survival ability of SIHP was much greater than that of the genetstnegativeS. aureus. We also found that IL-2, IL-6, and IL-17A secreted in the supernatant of SIHP infected macrophages increased significantly compared totstnegative control strains infected ones. MLST analysis showed that all of SIHP strains were classified into ST5 clone. To our knowledge, this study firstly showed that SIHP strains are a kind of methicillin resistant strains which express β-hemolysin highly and possess a potential high virulence, and it was suggested that SIHP should be paid more attention in hospital.
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Haifang
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Huasheng
authors.initials: H
authors.lastname: Gao
authors.affiliation: Department of Clinical Laboratory, The Fifth People's Hospital of Suzhou Suzhou, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Aiqing
authors.initials: A
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Minhui
authors.initials: M
authors.lastname: Miao
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Xie
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Yimai
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Huiqin
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University Suzhou, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Du
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics*; D002460:Cell Line; D018925:Chemokines / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D004768:Enterotoxins / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics*; D006801:Humans; D020381:Interleukin-17 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism / Q000382:microbiology; D055624:Methicillin-Resistant Staphylococcus aureus; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D046915:Penicillin-Binding Proteins / Q000235:genetics; D010641:Phenotype; D012333:RNA, Messenger / Q000096:biosynthesis; D012756:Sheep; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics*; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D018089:Superantigens / Q000235:genetics; D013534:Survival; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D018925:Chemokines; D016207:Cytokines; D004768:Enterotoxins; D016326:Extracellular Matrix Proteins; D006460:Hemolysin Proteins; D020381:Interleukin-17; D007376:Interleukin-2; D015850:Interleukin-6; D046915:Penicillin-Binding Proteins; D012333:RNA, Messenger; D018089:Superantigens; D037521:Virulence Factors; C030107:enterotoxin F, Staphylococcal; C487789:mecA protein, Staphylococcus aureus; C021091:staphylococcal alpha-toxin; D013108:Sphingomyelin Phosphodiesterase; C029878:hlb protein, Staphylococcus aureus
keywords: Staphylococcus aureus; drug resistance; hemolysin; incomplete hemolytic phenotype; virulence