ABSTRACT
Objective:To investigate the characteristics of hemolysis, resistance and homology of Staphylococcus cohnii urealyticum. Methods:A retrospective study was carried out on thirteen clinical strains of Staphylococcus cohnii urealyticum. They were re-identified by MALDI-TOF MS. Their colony and hemolytic characteristics on blood agar plates were observed. The co-hemolysis between Staphylococcus cohnii urealyticum and Staphylococcus aureus was demonstrated. The hemolysin genes and drug resistance genes were detected by PCR. Pulsed field gel electrophoresis and mass spectrometry were used to analyze the homology of strains. The susceptibility of strains to antimicrobial agents was detected by agar dilution. Results:The confirmed 13 strains of Staphylococcus cohnii urealyticum showed various levels of hemolysis and had enhanced synergistic hemolysis with Staphylococcus aureus. All strains were susceptible to vancomycin and tigecycline. There were 12 strains which carried mecA gene, 7 strains carried cfr gene, 7 strains carried ermC gene. The 13 strains were divided into 3 groups by MALDI-TOF MS, and 6 types by pulsed field gel electrophoresis. Conclusions:Clinical strains of Staphylococcus cohnii urealyticum demonstrated various levels of hemolysis which could be enhanced by Staphylococcus aureus. Although they carried different drug resistance genes, they were all susceptible to vancomycin and tigecycline.
ABSTRACT
Objective@#To investigate the characteristics of hemolysis, resistance and homology of Staphylococcus cohnii urealyticum.@*Methods@#A retrospective study was carried out on thirteen clinical strains of Staphylococcus cohnii urealyticum. They were re-identified by MALDI-TOF MS. Their colony and hemolytic characteristics on blood agar plates were observed. The co-hemolysis between Staphylococcus cohnii urealyticum and Staphylococcus aureus was demonstrated. The hemolysin genes and drug resistance genes were detected by PCR. Pulsed field gel electrophoresis and mass spectrometry were used to analyze the homology of strains. The susceptibility of strains to antimicrobial agents was detected by agar dilution.@*Results@#The confirmed 13 strains of Staphylococcus cohnii urealyticum showed various levels of hemolysis and had enhanced synergistic hemolysis with Staphylococcus aureus. All strains were susceptible to vancomycin and tigecycline. There were 12 strains which carried mecA gene, 7 strains carried cfr gene, 7 strains carried ermC gene. The 13 strains were divided into 3 groups by MALDI-TOF MS, and 6 types by pulsed field gel electrophoresis.@*Conclusions@#Clinical strains of Staphylococcus cohnii urealyticum demonstrated various levels of hemolysis which could be enhanced by Staphylococcus aureus. Although they carried different drug resistance genes, they were all susceptible to vancomycin and tigecycline.
ABSTRACT
Uropathogenic Escherichia coli ( UPEC) is the most common pathogen causing urinary tract infection ( UTI).Various virulent factors of UPEC involved in the pathogenic process of UTI , including adhesins, iron uptake-related factors, protectins, and toxins.Adhesion factors can help UPEC to adhere to the surface of the epithelial cell in the host urinary tract.Iron ion acquisition factors can help the pathogen to get iron from the host body , and then multiply and cause disease.Various toxins produced by the pathogen can cause damage to the host epithelial cells and release of nutrients and other nutritional factors that help UPEC to survive and grow.Protectins can protect UPEC from the host complement system mediated bactericidal effect and the phagocytosis of phagocytic cells.In this review , the most recent research progress on the various virulence characteristics of UPEC will be discussed.