Title : Molecular and Biochemical Characterization of Escherichia coli NCCP strains in Korea
The National Culture Collection for Pathogens (NCCP) is the biobank of the Korea Centers for Disease Control & Prevention and has a variety of clinically isolated pathogens from Korea. The NCCP strives to contribute to healthcare industries with its characterized strains. The informative characteristics of each resource are used to research, education, and develop alternative reference strains in medical institutes and industrial companies in Korea.
Escherichia coli are bacteria found in the environment, food, and intestines of humans and animals. Although most strains of E. coli are harmless, but some strains can cause diarrhea, while others cause urinary tract infections, respiratory illness, and pneumonia. E. coli strains, depending on their characteristics are being researched and utilized by the pharmaceutical cosmetic and food industries.
E. coli is among the most common species stored in the NCCP. We have clinically isolated 282 strains and analyzed their molecular and biochemical characteristics. O serotyping and antibiotic susceptibility testing using MIC (Minimum Inhibitory Concentration) measurements for biochemical characterization, as well as 16S rRNA sequencing, MLST (Multilocus sequence typing) genotyping, toxin type gene detection, and antibiotic resistance gene detection for genetic characterization were performed. O serotyping experiments identified 106 serotypes and 103 MLST sequence type (ST) numbers were identified. The ST results of the two strains revealed new types, and the MLST sequencing analysis data were registered in PubMLST. Eight toxin-type genes, namley, aggR, VT1 (stx1), LT, bfpA, VT2 (stx2), eaeA, ST (STh / STp) and ipaH, were examined using PCR. Antibiotic susceptibility testing showed 30 strains of CRE strains and 43 strains of ESBL-producing.
Characterization information and quality assurance resources obtained from this study can be distributed to researchers and used as valuable reference materials in healthcare fields, as well as in national certification testing to develop diseases diagnostic products.
This study was supported by the fund of the Korea Centers for Disease Control & Prevention, Ministry of Health and Welfare (Funding no. 2019-NG-047-00).