Antimutator Activity of the Nudix Hydrolases from E. coli

Abstract

Enzymes of the Nudix Hydrolase superfamily are characterized by the ability to hydrolyze substrates containing nucleoside diphosphate linked to some moiety x, hence the acronym Nudix. Within the Nudix superfamily, MutT is an established antimutator. This functionality is a point of debate for some of the other members of the superfamily. Experiments to analyze antimutator activity were carried out on the 13 Nudix hydrolase E. coli knockouts. Overnight cultures of each E. coli knockout were grown and plated on LB‐agar containing Streptomycin or Nalidixic Acid, or diluted a million‐fold and plated on LB‐agar or LB‐agar containing Kanamycin (knockouts all contain Kanamycin resistance markers). After ~16 hours incubation at 37 °C, colonies were counted. The MutT knockout demonstrated the ability to gain antibiotic resistance to Streptomycin and Nalidixic Acid as observed by many viable colonies on all plates. The other Nudix hydrolase E. coli knockouts grew on LB‐agar and in the presence of Kanamycin but not in the presence of Streptomycin or Nalidixic Acid. These results indicate that MutT from E. coli is in fact an antimutator, as previously established, but the other Nudix hydrolases from E. coli are not antimutators. Complementation studies with Nudix hydrolases from M. tuberculosis will be carried out to determine which, if any, are antimutators comparable to MutT from E. coli.Support or Funding InformationRIT College of Science FEAD grant (SOH)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.