[Reactivating factor of Luteococcus japonicus subsp. casei: isolation and characterization].

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Context:

• A producer strain of reactivating factor (RF) was identified.
• The strain is physiologically, biochemically, and genetically similar to Luteococcus japonicus DSM 10546.
• Phenotypical differences led to its classification as a new subspecies, Luteococcus japonicus subsp. casei.

Purpose:

• To characterize the producer strain of reactivating factor (RF).
• To investigate the nature and function of the secreted RF.
• To identify bioactive metabolites produced by L. casei.

Summary:

• The producer strain was identified as Luteococcus japonicus subsp. casei, a subspecies of L. japonicus.
• Reactivating factor (RF) is secreted into the medium and functions as a signaling molecule.
• RF exhibits antioxidant activity, suggesting a protective role. Four biologically active components were isolated from the culture medium, with the most active being a polypeptide containing amino acid and sugar residues.

Impact:

• Establishes a new subspecies, Luteococcus japonicus subsp. casei.
• Identifies RF as a secreted signaling molecule with potential therapeutic applications due to its antioxidant properties.
• Characterizes novel bioactive metabolites from L. casei, opening avenues for further research in microbial products.