Norvaline and/or other amino acids that are capable of being acylated onto tRNALeu by LeuRS, in combination with substituted benzoxaboroles, such as a compound having a structure according to formula III:and methods for decreasing the frequency of resistance and/or reducing the rate of resistance and/or suppressing the emergence of resistance that develops in bacteria exposed to a substituted benzoxaborole or salt thereof by administering a combination of a substituted benzoxaborole such as a compound of formula III or salt thereof and an amino acid or a salt thereof.