Related Experiment Video
Updated: Aug 6, 2026
Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination
Published on: September 25, 2014
Development of a DNA microarray to identify the Streptococcus pneumoniae serotypes contained in the 23-valent
Quan Wang1, Min Wang, Fanrong Kong
1TEDA School of Biological Sciences and Biotechnology, Nankai University, 23# HongDa Street, TEDA, Tianjin 300457, China.
Abstract:
Streptococcus pneumoniae is a major worldwide human pathogen. This investigation has developed a reliable and accurate DNA microarray method for inter-species differentiation of S. pneumoniae and intra-species differentiation of the 23 groups of S. pneumoniae including serotypes represented in the 23-valent pneumococcal vaccine and the other 20 closely related serotypes. In addition to 16S rDNA probes, serotype- or serogroup-specific probes targeting the capsular polysaccharide synthesis (cps) genes, wzy or capA were generated. We adopted a two-step multiplex PCR to improve the sensitivity of detection to a level of 10(5) cfu/ml in pure culture or 50 ng DNA. A total of 169 isolates (from China, Australia, Canada and New Zealand) including 147 belonging to 23-valent vaccine and closely related serotypes of S. pneumoniae, 11 belonging to other serotypes and 11 of different species commonly isolated from respiratory tract were tested to verify the method. The DNA microarray method developed provides a sensitive means to rapidly identify the members of the most common S. pneumoniae serotypes in patients and to monitor their distribution in different patient groups and geographic locations. Such information is needed for disease surveillance and to monitor vaccine efficacy.
Insights
A new DNA microarray method accurately identifies Streptococcus pneumoniae strains, aiding in disease surveillance and vaccine efficacy monitoring. This tool differentiates between species and specific serotypes, crucial for public health.
Area of Science:
- Microbiology
- Molecular Biology
- Medical Diagnostics
Background:
- Streptococcus pneumoniae is a significant global human pathogen.
- Accurate identification and differentiation of S. pneumoniae serotypes are critical for disease surveillance and vaccine development.
- Existing methods may lack the sensitivity or specificity required for comprehensive epidemiological studies.
Purpose of the Study:
- To develop a reliable and accurate DNA microarray method for differentiating Streptococcus pneumoniae species and serotypes.
- To target specific virulence genes, including capsular polysaccharide synthesis (cps) genes (wzy, capA), and 16S rDNA for enhanced specificity.
- To validate the method's sensitivity and accuracy using a diverse collection of bacterial isolates.
Main Methods:
- Development of a DNA microarray utilizing probes for 16S rDNA and serotype/serogroup-specific targets (cps genes: wzy, capA).
- Implementation of a two-step multiplex polymerase chain reaction (PCR) to enhance detection sensitivity.
- Testing the microarray method on 169 isolates, including various S. pneumoniae serotypes and other respiratory tract species.
Main Results:
- The DNA microarray method achieved high accuracy in inter-species and intra-species differentiation of S. pneumoniae.
- Sensitivity was improved to detect as low as 10(5) CFU/ml in pure culture or 50 ng of DNA.
- The method successfully identified 147 isolates belonging to the 23-valent vaccine and related serotypes, along with other serotypes and species.
Conclusions:
- The developed DNA microarray is a sensitive and rapid tool for identifying common S. pneumoniae serotypes.
- This method enables effective monitoring of S. pneumoniae distribution across patient groups and geographic locations.
- The findings support the utility of the DNA microarray for disease surveillance and assessing pneumococcal vaccine efficacy.
