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ARS Home » Plains Area » Lincoln, Nebraska » Agroecosystem Management Research » Research » Publications at this Location » Publication #421609
Research Project: Managing Manure as a Soil Resource for Improved Biosecurity, Nutrient Availability, and Soil Sustainability

Location: Agroecosystem Management Research

Title: Development of quantitative controls for environmental and agricultural surveillance of extended-spectrum beta-lactamase producing (ESBL) Escherichia coli

Author
item Durso, Lisa
item Condon, Justine
item Wells, James
item Frye, Jonathan
item Sharma, Manan
item Ibekwe, Abasiofiok

Submitted to: Protocols.io
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2025
Publication Date: 2/20/2025
Citation: Durso, L.M., Condon, J.C., Wells, J., Frye, J.G., Sharma, M., Ibekwe, A.M. 2025. Development of quantitative controls for environmental and agricultural surveillance of extended-spectrum beta-lactamase producing (ESBL) Escherichia coli. Protocols.io. https://doi.org/10.17504/protocols.io.eq2ly6zdwgx9/v1.
DOI: https://doi.org/10.17504/protocols.io.eq2ly6zdwgx9/v1

Interpretive Summary: This work is a protocol that provides instructions for making bacterial stocks that have a very precise number of cells. It uses two new Escherichia coli strains isolated by ARS scientists, specifically for work with E. coli in agricultural and environmental settings. They are a matched pair, with one that is a negative control for two important types of antibiotic resistance, and the other a positive control. These precisely counted stocks are used as a reference, to measure how many E. coli there are in a sample with and without the two types of antibiotic resistance. They will be useful for tracking and measuring antibiotic resistance in soil and water, and can be useful for testing how well new detection methods work.

Technical Abstract: The importance of standardized control strains for environmental antibiotic resistance (AR) efforts cannot be underestimated. Control strains are useful in standardizing the quality of testing across laboratories and are essential for quality control of experimental procedures and reagents.  This protocol introduces two new agriculturally sourced Escherichia coli strains for use as environmental AR control strains in method development, surveillance, and research efforts.  Both strains are fully characterized, and whole-sequenced, and are available through multiple public sources.  ARS-C101 is a negative control strain that is extended-spectrum ß-lactamase (ESBL) negative and tetracycline susceptible.  ARS-C301 is a positive control that is ESBL positive, and tetracycline resistant.  They are both compatible with the World Health Organization "WHO integrated global surveillance on ESBL-producing E. coli using a “One Health” approach: implementation and opportunities.”  (aka Tricycle”) efforts, and the current protocol describes how to make quantitative controls of ARS-C101 and ARS-C301 control strains using a modification of the WHO Tricycle protocol.