Resistance to Beta-Lactam Antibiotics in Mucoid Mutants of Escherichia coli

Harleen Tewatia, “Resistance to Beta-Lactam Antibiotics in Mucoid Mutants of Escherichia coli
Mentor: Alita Burmeister, Biological Sciences
Poster #195

In Escherichia coli, the mucoid phenotype is a virulence factor that can produce harmful effects related to biofilm formation. Some mucoid mutants are additionally known to have increased resistance to the antibiotics cefsulodin and amdinocillin. We previously isolated and characterized mucoid mutants with variable resistance levels to the bacteriophage U136B. To determine if these mutants also have increased antibiotic resistance, we measured MICs using broth microdilution and efficiency of plating assays with cefsulodin and amdinocillin. We observed increased antibiotic resistance of the mucoid mutants compared to wild type and tolC mutant controls. In future work, we will test resistance to a broader panel of clinically relevant antibiotics. Overall, this work will address whether the phage-selected mucoid phenotype poses a risk to phage therapy in the form of increased antibiotic resistance.