3 Biotech

, 9:132 | Cite as

Genomic characterization of a potentially novel Streptococcus species producing exopolysaccharide

  • Longzhan Gan
  • Yi Zhang
  • Rui Tang
  • Beike Liu
  • Shiting Wang
  • Mengyao Hu
  • Zhenjiang LiEmail author
  • Yongqiang TianEmail author
Genome Reports


Human oral streptococci, particularly the mitis group, often dwell in the upper respiratory tracts, oral mucosa, and tooth surfaces of healthy individuals. In this work, an α-hemolytic strain, designated LQJ-218, was isolated from the human oral cavity and evaluated for its ability to produce exopolysaccharides. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain is a potentially novel species belonging to the mitis group streptococci. Whole-genome sequence-based analysis indicated that the genome sequence of Streptococcus sp. LQJ-218 was 1,935,194 bp in length, with a mol% G + C content of 40.0, and contained 1897 coding DNA sequences and 91 RNA genes. Furthermore, four biosynthetic gene clusters relevant to exopolysaccharide production were identified in the genome. Both digital DNA–DNA hybridization (yielding a value of 56.60% between strain LQJ-218 and its nearest relative S. mitis) and average nucleotide identity analysis (revealing 91.29% identity of LQJ-218 with its nearest relative S. mitis) suggested that strain LQJ-218 should be classified as a novel Streptococcus species. This potentially novel strain may possess great potential for contributing to the development of new exopolysaccharides. The present study provides valuable genetic information that may be useful in comparative genomics and biotechnological applications.


Oral streptococci Whole-genome sequencing Exopolysaccharide Novel species 



This work was financially supported by the National Key Research and Development Program of China (2017YFB0308401) and Sichuan Key Research and Development Program (2017GZ0430).

Compliance with ethical standards

Conflict of interest

The authors declare that there are no conflicts of interest.

Ethical approval

This work does not contain any studies with human participants or animals performed by any of the authors.

Supplementary material

13205_2019_1652_MOESM1_ESM.pdf (409 kb)
Supplementary material 1 (PDF 409 KB)


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Copyright information

© King Abdulaziz City for Science and Technology 2019

Authors and Affiliations

  • Longzhan Gan
    • 1
  • Yi Zhang
    • 2
  • Rui Tang
    • 3
  • Beike Liu
    • 4
  • Shiting Wang
    • 1
  • Mengyao Hu
    • 1
  • Zhenjiang Li
    • 2
    Email author
  • Yongqiang Tian
    • 1
    Email author
  1. 1.Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Light Industry, Textile & Food EngineeringSichuan UniversityChengduPeople’s Republic of China
  2. 2.Chengdu Jinkai Biology Engineering Co., LtdChengduPeople’s Republic of China
  3. 3.The Middle School Attached to Sichuan Normal UniversityChengduPeople’s Republic of China
  4. 4.Chengdu Shude High SchoolChengduPeople’s Republic of China

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