[Analysis of different Lactobacillus rhamnosus by random amplified polymorphic DNA]

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Context:

• Lactobacillus rhamnosus is a probiotic bacterium found in the human gut.
• Understanding the genetic diversity of L. rhamnosus is crucial for its application in health and industry.
• Isolates were obtained from elderly individuals (>90 years) in distinct geographical regions of China (Hetian, Xinjiang and Bama, Guangxi).

Purpose:

• To develop and optimize a molecular method for distinguishing between different strains of Lactobacillus rhamnosus.
• To analyze the genetic diversity and relationships among L. rhamnosus isolates from elderly Chinese populations.
• To assess the efficacy of the random amplified polymorphic DNA (RAPD) technique for strain differentiation.

Summary:

• A random amplified polymorphic DNA (RAPD) technique was established using five specific primers (P14, OPG28, OPG25, P7, P4) to analyze eleven Lactobacillus rhamnosus isolates.
• RAPD analysis yielded clear, stable DNA fingerprints with polymorphic band patterns, indicating significant genetic variation among the strains.
• Genetic similarity coefficients ranged from 0.581 to 0.935, clustering the eleven isolates into five distinct groups, with geographical origin influencing the clustering.

Impact:

• The developed RAPD method is effective for molecular marking and differentiation of Lactobacillus rhamnosus strains.
• The study highlights a high level of genetic diversity and distinct genetic relationships among L. rhamnosus isolates from different geographical locations in China.
• Findings contribute to a deeper understanding of Lactobacillus rhamnosus population genetics and strain variability.