Identification of a fmtA-like gene that has similarity to other PBPs and beta-lactamases in Staphylococcus aureus

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• Staphylococcus aureus is a significant pathogen.
• Methicillin resistance in S. aureus is a major clinical concern.
• Penicillin-binding proteins (PBPs) and FmtA are implicated in cell wall synthesis and antibiotic resistance.

Purpose of the Study:

• To identify and characterize a novel gene, flp, in Staphylococcus aureus.
• To investigate the potential role of the FLP protein in cell wall synthesis and methicillin resistance.

Main Methods:

• Gene identification and sequencing from S. aureus.
• Bioinformatic analysis of the deduced amino acid sequence.
• Recombinant protein expression and activity assays.
• Gene inactivation in methicillin-resistant S. aureus strains.

Main Results:

• The flp gene encodes a 489-amino acid protein (FLP) with a molecular mass of 56.4 kDa.
• FLP shares sequence similarity with PBPs and FmtA, possessing conserved motifs found in PBPs and beta-lactamases.
• Recombinant FLP protein demonstrated no penicillin-binding activity.
• Inactivation of the flp gene did not alter methicillin resistance levels in S. aureus.

Conclusions:

• The FLP protein, despite structural similarities, does not appear to be a functional penicillin-binding protein.
• The flp gene is not a significant determinant of methicillin resistance in the studied S. aureus strains.
• The precise function of FLP in S. aureus remains to be elucidated.