A multiple antibiotic-resistant enterobacter cloacae strain isolated from a bioethanol fermentation facility

Area of Science:

• Microbiology
• Industrial Biotechnology
• Environmental Science

Background:

• Bioethanol fermentation facilities utilize antibiotics to prevent microbial contamination.
• Enterobacter cloacae is a bacterium found in various environments, including industrial settings.
• Antibiotic resistance in industrial microorganisms poses challenges for process efficiency and control.

Purpose of the Study:

• To investigate antibiotic resistance in Enterobacter cloacae isolated from bioethanol fermentation.
• To identify the genetic basis of resistance in the studied strain.
• To assess the impact of antibiotics on bacterial behavior, specifically biofilm formation, in the context of bioethanol production.

Main Methods:

• Isolation and identification of Enterobacter cloacae F3S3 from bioethanol fermentation samples.
• Polymerase Chain Reaction (PCR) assays to detect antibiotic resistance genes (ampC for penicillin, ermG for erythromycin).
• Biofilm formation assays under varying antibiotic concentrations and high ethanol content.

Main Results:

• Enterobacter cloacae F3S3 displayed significant resistance to prophylactically added antibiotics.
• The strain carried genes conferring resistance to penicillin (ampC) and erythromycin (ermG).
• Erythromycin exposure stimulated biofilm formation in E. cloacae F3S3, enhancing its survival under antibiotic stress.

Conclusions:

• Enterobacter cloacae F3S3 possesses genetic mechanisms for antibiotic resistance relevant to bioethanol production.
• The ability to form biofilms under antibiotic pressure contributes to the persistence of this bacterium in fermentors.
• Findings highlight the need for strategies to manage antibiotic-resistant bacteria in industrial fermentation processes.