AUTHOR=Jiang Yu , Li Xianping , Zhang Wei , Ji Yadong , Yang Kai , Liu Lu , Zhang Minghui , Qiao Weicang , Zhao Junying , Du Mengjing , Fan Xiaofei , Dang Xingfen , Chen Huo , Jiang Tiemin , Chen Lijun 

TITLE=Effect of folA gene in human breast milk-derived Limosilactobacillus reuteri on its folate biosynthesis

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 15 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1402654

DOI=10.3389/fmicb.2024.1402654

ISSN=1664-302X

ABSTRACT=Folate supplementation is crucial for the human body, and the chemically synthesized folic acid might have undesirable side e ffects. The use of molecular breeding methods to modify the genes related to the biosynthesis of folate by probiotics to increase folate production is cur rently a focus of research. In this study, the folate-producing strain of Limosilactobacillus reuteri B1-28 was isolated from human breast milk, and the difference between B1-28 and folA gene deletion strain ΔFolA was investigated by phenotyping, in vitro probiotic evaluation, metabolism and transcriptome analysis. The results showed that the folate producted by the ΔFolA was 2-3 folds that of the B1-28. Scanning electron microscope showed that ΔFolA had rougher surface, and the acid-producing capacity (P = 0.0008) and adhesion properties (P = 0.0096) were significantly enhanced than B1-28. Transcriptomic analysis revealed that differentially expressed genes were mainly involved in three pathways, among which the biosynthesis of ribosome and aminoacyl-tRNA occurred in the key metabolic pathways. Metabolomics analysis showed that folA affected 5 metabolic pathways, involving 89 different metabolites. In conclusion, the editing of a key gene of folA in folate biosynthesis pathway provides a feasible pathway to improve folate biosynthesis in breast milk-derived probiotics.