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Updated: Aug 5, 2026
04:40
The Cultivation, Growth, and Viability of Lactic Acid Bacteria: A Quality Control Perspective
Published on: June 16, 2022
Lactococcus cremoris subsp. sagaensis subsp. nov., Isolated from Naturally Fermented Yogurt
Lin Cheng1, Tian-Xue Wang1, Chun Yan Li2
1College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
Current Microbiology
|July 29, 2026
Summary
Four lactic acid bacteria from fermented yogurt were identified as a new subspecies, Lactococcus cremoris subsp. sagaensis. This discovery expands the understanding of lactic acid bacteria diversity in fermented foods.
Area of Science:
- Microbiology
- Food Science
- Bacteriology
Background:
- Lactic acid bacteria are crucial for fermented food production.
- Naturally fermented products harbor diverse microbial communities.
- Characterization of novel strains is essential for understanding microbial diversity and potential applications.
Purpose of the Study:
- To characterize four lactic acid bacteria isolated from naturally fermented yogurt.
- To determine the taxonomic and phylogenetic relationships of these isolates.
- To propose a new subspecies if distinct characteristics are identified.
Main Methods:
- Polyphasic taxonomic approach.
- 16S rRNA gene, pheS, recA, and rpoB sequence analyses.
- Phylogenomic tree construction.
- Average Nucleotide Identity (ANI) and digital DNA-DNA hybridization (dDDH) calculations.
- Phenotypic characterization.
Main Results:
- The four isolates (1030T, 1245, X2047, and 5 - 2) were phylogenetically closely related to *Lactococcus cremoris*.
- ANI and dDDH values indicated the isolates belonged to the *L. cremoris* species.
- Significant phenotypic differences were observed between the isolates and known *L. cremoris* subspecies.
- A novel subspecies, *Lactococcus cremoris* subsp. *sagaensis* subsp. nov., was proposed with strain 1030T as the type strain.
Conclusions:
- The isolated lactic acid bacteria represent a novel subspecies, *Lactococcus cremoris* subsp. *sagaensis*.
- This finding contributes to the understanding of lactic acid bacteria diversity in fermented foods from the Xizang Autonomous Region.
- The proposed subspecies enriches the taxonomic classification within the *Lactococcus* genus.
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