Physical and Biochemical Properties of N-Acetyl Transferase RimL of the Hyperthermophilic Bacteria Thermus thermophilus

Bacterial N-terminal acetyltransferases (NATs) are involved in the biosynthesis/degradation of antibiotics. The RimL enzyme from E. coli provides it with resistance to the antibiotic microcin C. To date, the NATs of pathogenic bacteria have been well studied, but there is no data on the NATs of thermophilic bacteria. The purpose of the work is to study the physicochemical properties and specificity of a new NAT — RimL from Thermus thermophilus. We cloned the RimL ORF (TTHA1799) and developed a method for purifying the enzyme. The stability of RimL to pH, high temperatures and denaturing agents was studied using the protein intrinsic fluorescence method. We have obtained a thermophilic enzyme that can be used in biotechnology for the acetylation of proteins and peptides under non-standard conditions.

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