A cfr-like gene from Clostridium difficile confers multiple antibiotic resistance by the same mechanism as the cfr...

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• The Cfr RNA methyltransferase is known to confer resistance to multiple antibiotics by methylating the A2503 site on 23S rRNA.
• Numerous 'cfr-like' gene sequences exist in databases, but their functional roles remain largely uncharacterized.

Purpose of the Study:

• To investigate the function of a Cfr-like protein identified in a Peptoclostridium difficile strain.
• To confirm if this Cfr-like protein possesses RNA methyltransferase activity and confers antibiotic resistance.

Main Methods:

• Expression of the Cfr-like protein from Peptoclostridium difficile in Escherichia coli.
• Determination of minimum inhibitory concentrations (MICs) for various antibiotic classes.
• Analysis of 23S rRNA modification using primer extension stop assays.

Main Results:

• The expressed Cfr-like protein from Peptoclostridium difficile demonstrated functional Cfr activity.
• Escherichia coli expressing the protein exhibited elevated MICs against five distinct classes of antibiotics.
• A primer extension stop assay confirmed methylation at the A2503 position of 23S rRNA.

Conclusions:

• The Cfr-like protein from Peptoclostridium difficile functions as an active Cfr RNA methyltransferase.
• This study validates the role of previously uncharacterized 'cfr-like' genes in conferring multidrug resistance.
• The findings contribute to understanding the spread and mechanisms of antibiotic resistance mediated by Cfr proteins.